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Salinas Rodríguez, Eleazar, Edgar A. Cárdenas-Reyes, Francisco R. Barrientos-Hernández, Javier Flores-Badillo, M. P. Gutiérrez-Amador, Ariadna Sánchez-Castillo, Otilio A. Acevedo-Sandoval, Eduardo Cerecedo-Sáenz e Juan Hernández-Ávila. "Ce and Nd Extraction by Cationic Exchange, Using Bentonite, Diatomite, and Eggshell—Preliminary Study". Minerals 13, n. 6 (29 maggio 2023): 735. http://dx.doi.org/10.3390/min13060735.
Testo completoAbstract (sommario):
China, Vietnam, Brazil, and Russia have the largest deposits of rare earths. However, in recent works, the occurrence of light rare earth elements has been demonstrated in an exhalative sedimentary type mineral (SEDEX) in Mexico, with adequate Ce and Nd contents. Additionally, it is this mineral that has been used to study the cation exchange capacity of non-metallic minerals and organic materials, such as bentonite, diatomite, and eggshell. To carry out this work, the crushed and ground SEDEX ore was leached using HCl, H2SO4, and HNO3. Subsequently, the liquid containing the Ce and Nd ions extracted from the mineral was put in contact with the respective ion exchangers, evaluating the effect of temperature and pH to determine the cation exchange efficiency of each exchanger tried. It was found that the best leaching results were achieved with the H2SO4, obtaining an extraction of Ce and Nd of 97.6% and 95.7%, respectively. On the other hand, in the case of cation exchange, the best results found for the extraction of Ce and Nd were using diatomite at a temperature of 323 K and a pH of 3, obtaining an extraction of 99.06% Ce and 99.07% Nd.
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Ponomareva, Maria, Olga Cheremisina, Yulia Mashukova e Elena Lukyantseva. "Increasing the efficiency of rare earth metal recovery from technological solutions during processing of apatite raw materials". Записки Горного института 252 (17 dicembre 2021): 1–10. http://dx.doi.org/10.31897/pmi.2021.6.13.
Testo completoAbstract (sommario):
The issues of complex processing of mineral resources are relevant due to the depletion of available raw materials. So, it is necessary to involve technological waste, generated during the processing of raw materials, to obtain valuable components. In the process flow of apatite concentrate treatment using the sulfuric acid method, a large amount of phosphogypsum is produced with an average content of light rare earth metals (REMs) reaching 0.032-0.45 %. When phosphogypsum is treated with sulfuric acid solutions, a part of REMs is transferred to the sulfate solution, from which it can be extracted by means of ion exchange method. The study focuses on sorption recovery of light REMs (praseodymium, neodymium and samarium) in the form of anionic sulfate complexes of the composition [ln(SO4)2]– on polystyrene anion exchanger AN-31. The experiments were performed under static conditions at a liquid-to-solid ratio of 1:1, pH value of 2, temperature of 298 K and initial REM concentration in the solutions ranging from 0.83 to 226.31 mmol/kg. Thermodynamic description of sorption isotherms was carried out by the method based on linearization of the mass action equation, modified for the ion exchange reaction. As a result of performed calculations, the authors obtained the constants of ion exchange equilibrium for Pr, Nd and Sm, as well as the values of the change in the Gibbs energy for the ion exchange of REM sulfate complexes on the AN-31 anion exchanger and the values of total capacity of the anion exchanger. Calculated separation factors indicated low selectivity of AN-31 anionite exchanger for light REMs; however, the anion exchanger is suitable for effective recovery of a sum of light REMs. Based on the average value of ion exchange equilibrium constant for light REMs, parameters of a sorption unit with a fluidized bed of anion exchanger were estimated.
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El-Sweify, Fatma H., Ehab A. A. El-Shazly e Shreen M. Salama. "Comparison of some organic and inorganic ion exchangers concerning the sorption of Ce(III), Te(IV), Zr(IV), Hf(IV) and Nb(V)". Radiochimica Acta 106, n. 3 (28 marzo 2018): 207–16. http://dx.doi.org/10.1515/ract-2017-2789.
Testo completoAbstract (sommario):
AbstractThe sorption behaviors of Ce(III), as a representative of trivalent lanthanide ions, and Te(IV), Zr(IV) and Nb(V) as fission products representatives, as well as Hf(IV), from various aqueous media on some synthesized inorganic exchangers, as well as commercially available organic ion exchangers were studied and compared. Organic cation exchanger Dowex-50WX8 and organic anion exchangers AG-1X8 and AG-2X8 were utilized. Synthesized inorganic ion exchangers were zirconium titanium phosphate (ZrTiP) of different Zr:Ti mole ratios and ceric tungstate (CeW). The sorption was carried out from mineral acid solutions as well as EDTA and DTPA solutions. The radioactive isotopes,95Zr,95Nb,123mTe,141Ce and181Hf were used to trace the sorption behaviors of the corresponding elements, which were studied in mixtures of them. The differences between the sorption behaviors of the studied metal ionic species on both kinds of ion exchangers were interpreted and discussed in this work.
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Aliyah Shahab e Indah Agus Setiorini. "EFEKTIFITAS VOLUME RESIN ION EXCHANGER TERHADAP KAPASITAS PERTUKARAN ION DAN WAKTU JENUH PADA UNIT DEMIN PLANT DI PT PLN (PERSERO) UPDK KERAMASAN". Journal of Innovation Research and Knowledge 2, n. 9 (25 febbraio 2023): 3791–802. http://dx.doi.org/10.53625/jirk.v2i9.5407.
Testo completoAbstract (sommario):
Resin penukar ion pada sistem demineralisasi merupakan media yang digunakan dalam proses pengolahan air baku untuk menghasilkan air bebas mineral yang digunakan untuk proses produksi khususnya proses demin plant. Air demineralisasi merupakan air yang telah mengalami proses penghilangan kation anion yang terkandung didalamnya. Kandungan mineral sebagai bentuk kation anion dalam air, prinsip Unit Demin Plant PT PLN (Persero) UPDK Keramasan merupakan unit pengolahan air bersih sehingga didapatkan air demin (demineralized water) yang bebas dari mineral berupa garam–garam terlarut. Proses pertukaran ion Unit Demin Plant yang ada di PT PLN (Persero) UPDK Keramasan adalah pada saat air melewati campuran resin kation dan anion yang terdapat didalam demin plant, maka terjadilah proses ion exchange (pertukaran ion).Perhitungan ini bertujuan untuk mengetahui kebutuhan resin yang digunakan di PT PLN (Persero) UPDK Keramasan, resin yang didapatkan yaitu volume kolom kation pada saat tinggi 90 cm adalah 435,362L dan saat tinggi 120 cm adalah 580,483L, volume kolom anion pada saat tinggi 90 cm 435,362L dan saat tinggi 120 cm adalah 580,483L. Kapasitas Pertukaran Ion kolom kation pada saat tinggi 90 cm adalah 957,796 eq dan pada saat tinggi 120 cm adalah 1277,06 eq, Kapasitas Pertukaran ion kolom anion pada saat tinggi 90cm adalah 478,898 eq dan pada saat tinggi 120 cm adalah 638,531 eq, serta waktu jenuh kolom kation dan anion adalah 33,33 hari.
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De Luca, Pierantonio, Ivano Bernaudo, Rosangela Elliani, Antonio Tagarelli, Jànos B.Nagy e Anastasia Macario. "Industrial Waste Treatment by ETS-10 Ion Exchanger Material". Materials 11, n. 11 (18 novembre 2018): 2316. http://dx.doi.org/10.3390/ma11112316.
Testo completoAbstract (sommario):
The aim of this project was to study the treatment of industrial waste using ETS-10 zeolite. The pollutants that must be removed were metals sourced from zinc ferrite, a processing waste derived from the use of mineral-containing zinc. The first phase of the work involved the characterization of the industrial waste, zinc ferrite, in order to deepen the knowledge regarding its nature and composition. The second phase involved the removal of the metals released by the zinc ferrite in aqueous systems using the ETS-10 phase as an ion exchanger. Different chemical and physical techniques were used: plasma mass spectrometry, X-ray diffraction, scanning electron microscopy, microanalysis, and thermal analyses. A comparison between ETS-10 and commercial zeolite A performance, in the same aqueous systems, was carried out. The results showed that the metal removal efficiency of ETS-10 phase is higher than that obtained by commercial zeolite A, especially towards dangerous heavy metals such as Pb, Zn and Mn.
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Vasil’eva, Vera I., Elmara M. Akberova, Ali M. Saud e Victor I. Zabolotsky. "Current-Voltage Characteristics of Membranes with Different Cation-Exchanger Content in Mineral Salt—Neutral Amino Acid Solutions under Electrodialysis". Membranes 12, n. 11 (2 novembre 2022): 1092. http://dx.doi.org/10.3390/membranes12111092.
Testo completoAbstract (sommario):
The features of the electrochemical behavior of experimental heterogeneous ion-exchange membranes with different mass fractions of sulfonated cation-exchange resin (from 45 to 65 wt%) have been studied by voltammetry during electrodialysis. Electromembrane systems with 0.01 M NaCl solution and with a mixed 0.01 M NaCl + 0.05 M phenylalanine (Phe) solution have been investigated. A significant influence of the ion-exchanger content on the parameters of current-voltage curves (CVCs) was established for the first time. Electrodialysis of the sodium chloride solution revealed a decrease in the length of the limiting current plateau and in the resistances of the second and third sections of the CVCs with an increase in the resin content in the membrane. The fact of the specific shape of the CVCs of all studied cation-exchange membrane samples in mixed solutions of the mineral salt and the amino acid was established. A specific feature of current-voltage curves is the presence of two plateaus of the limiting current and two values of the limiting current, respectively. This phenomenon in electromembrane systems with neutral amino acids has not been found before. The value of the first limiting current is determined by cations of the mineral salt, which are the main current carriers in the system. The presence of the second plateau and the corresponding second limiting current is due to the appearance of additional carriers due to the ability of phenylalanine as an organic ampholyte to participate in protolytic reactions. In the cation-exchange electromembrane system with the phenylalanine containing solution, two mechanisms of H+/OH− ion generation through water splitting and acid dissociation are shown. The possibility of the generation of H+/OH− ions at the enriched solution/cation-exchange membrane interface during electrodialysis of amino acid containing solutions is shown for the first time. The results of this study can be used to improve the process of electromembrane demineralization of neutral amino acid solutions by both targeted selection or the creation of new membranes and the selection of effective current operating modes.
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Rathore, Sawai Singh, Archana Joshi, Hanuman . e Vikal Gupta. "Synthesis and environmental application of TTCHEA resin in effluent handling". Research Journal of Chemistry and Environment 26, n. 11 (25 ottobre 2022): 63–67. http://dx.doi.org/10.25303/2611rjce063067.
Testo completoAbstract (sommario):
Industrial effluents include significant amounts of heavy metals. The elimination of these ions causes great concern towards the environment. The flora and fauna of the aquatic and terrestrial environments are significantly impacted by rising levels of these metal pollutants in the environment. In order to develop new chelating resin, tamarind kernel powder was employed. TKP derivative of tertiary amine acts as metal ion exchanger cum a janitor for removal of harmful toxic metal ions from effluents of mineral and metallurgical industries. This study describes adsorption process for removal of toxic metal ions from wastewater. In dioxane medium, serine was bound to TKP backbone. The resulting ion exchange resin has been used for treatment of effluents. Interesting data were obtained showing the way in which various metal pollutants were removed throughout the depth of resin bed. FTIR methods have been used to describe the structure of the chelating resin.
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Septiyani, Elda, Yuniati Zevi e Nur Novilina Arifianingsih. "SUSTAINABLE REGENERATION OF MORDENITE MINERAL AS ION EXCHANGER FOR REMOVAL IRON AND MANGANESE IN GROUNDWATER". MATTER: International Journal of Science and Technology 6, n. 1 (7 luglio 2020): 147–60. http://dx.doi.org/10.20319/mijst.2020.61.147160.
Testo completo
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Kubová, J., V. Nevoral e V. Streško. "Determination of beryllium trace contents in mineral waters after preconcentration on a chelating ion-exchanger". Fresenius' Journal of Analytical Chemistry 348, n. 4 (aprile 1994): 287–90. http://dx.doi.org/10.1007/bf00324036.
Testo completo
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Zhanabayeva, A. K., G. K. Bishimbayeva, D. S. Zhumabayeva, A. M. Nalibayeva e Ye N. Abdikalykov. "A technology for producing electrode materials for lithium-ion batteries from Kazakhstan spodumene raw materials". Proceedings of Universities. Applied Chemistry and Biotechnology 12, n. 1 (1 aprile 2022): 141–52. http://dx.doi.org/10.21285/2227-2925-2022-12-1-141-152.
Testo completoAbstract (sommario):
This study aims to develop a technology for producing innovative electrode materials for modern lithium batteries. An efficient technology for post-purifying of technical lithium carbonate to reach the level of battery quality (99.95%) was developed. This technology involves causticiziation of technical lithium carbonate, ultrafiltration and ion-exchange sorption of a lithium hydroxide solution, followed by precipitation of lithium carbonate with ammonium carbonate. Cation-exchange resins of the brands Purolite S930Plus, Purolite S940 and Purolite S950 were studied for sorption purification of lithium-containing solutions from calcium and magnesium impurities. Purolite S940 and Purolite S950 can be recommended as the most effective cation exchangers. The kinetic parameters of calcium and magnesium sorption were determined using a Purolite S940 cation exchanger. The bicarbonation mode was set at room temperature and a pressure of 0.3 atm. The synthesized samples of lithium-iron-phosphate studied by the sol-gel method. The structures of the obtained electrode materials corresponding to the standard profile of lithium-iron-phosphate were investigated by X-ray diffraction. The synthesized electrode materials in the structure of lithium half- and button cells confirmed their good electrochemical properties, stable operation of batteries and a high intercalation reversibility of lithium ions in the samples within the potential range of 2.5–4.3 V. The main research results are innovative cathode and anode materials of a new generation for modern lithium-ion batteries with significantly increased capacity and stability of operation, obtained from lithium precursors – battery grade lithium carbonate based on domestic mineral and technogenic raw materials.
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Green, M., N. Denekamp, O. Lahav e S. Tarre. "Production of gaseous nitrogen compounds in a novel process for ammonium removal". Water Science and Technology 46, n. 1-2 (1 luglio 2002): 215–22. http://dx.doi.org/10.2166/wst.2002.0480.
Testo completoAbstract (sommario):
The production of gaseous nitrogen compounds, particularly the greenhouse gas nitrous oxide, was investigated in a novel process for ammonium removal from wastewater. The process is based on the adsorption of ammonium on zeolite followed by bioregeneration. The zeolite serves the dual purpose of an ion exchanger and a physical carrier for nitrifying bacteria which bio-regenerate the ammonium saturated mineral. An analysis of the nitrifying population composition in the reactor fed with simulated secondary effluent (NH4+ = 50 mg/l) revealed that about half of the bacteria in the biofilm were common ammonium oxidizers Nitrosococcus mobilis and Nitrosomonas, while the other half were nitrite oxidizers. The amount of nitrogen losses, under different conditions, and the identification of the emitted gases (N2 or N2O) were investigated in two sets of experiments: (I) batch experiments using biomass originating from the ion exchange reactor with and without the addition of nitrite, and (II) continuous experiments using the ion exchange reactor with zeolite as the biomass carrier. In the batch experiments, nitrite and oxygen concentrations were determined as the major parameters responsible for the formation of gaseous nitrogen gas during ammonia oxidation by autotrophic bacteria. Continuous experiments showed that the major parameter significantly affecting nitrogen losses was the amount of ammonium adsorbed by the zeolite during the ion exchange phase. The amount of ammonium adsorbed determines the ammonium concentration during the initial period of bioregeneration, which in turn directly influences oxygen demand and the resulting concentrations of oxygen and nitrite. It was concluded that the formation of nitrogen gas compounds in the ion exchange/bioregeneration process can be eliminated by adjusting the operational regime to have a shorter adsorption phase resulting in smaller amounts of ammonium adsorbed per cycle.
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Zhang, Zhihao, Yun Jia e Judong Zhao. "Effect of Magnesium Ion Concentration on the Scale Inhibition of Heat Exchanger in Circulating Cooling Water under Alternating Electric Field". Applied Sciences 10, n. 16 (8 agosto 2020): 5491. http://dx.doi.org/10.3390/app10165491.
Testo completoAbstract (sommario):
This work investigated the effect of magnesium ion concentration on the formation of mineral scale in circulating cooling water under alternating electric field treatment (AEFT) by using a self-made power plant circulating cooling water simulator. In this experiment, the circulating cooling water used was artificial hard water. Three experimental groups with different magnesium ion concentrations and three corresponding control groups were studied. Scale inhibition rate, fouling resistance, calcium ion concentration, crystal phase, and crystal morphology were discussed. Results showed that 4 mmol/L magnesium chloride promoted the formation of scale on the copper tube wall, and the average scale inhibition rate was −107.86%. When the magnesium chloride concentration was 6 mmol/L, the situation was reversed, and the average scale inhibition rate reached 59.11%. The changes in calcium ion concentration supported the scale inhibition rate. Scanning electron microscope (SEM) photos showed the change in the composition of calcium carbonate crystals. The results showed that the effect of AEFT on fouling resistance is nonlinearly related to the concentration of magnesium ions in circulating cooling water.
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Bronckers, A. L. J. J. "Ion Transport by Ameloblasts during Amelogenesis". Journal of Dental Research 96, n. 3 (19 dicembre 2016): 243–53. http://dx.doi.org/10.1177/0022034516681768.
Testo completoAbstract (sommario):
Hypomineralization of developing enamel is associated with changes in ameloblast modulation during the maturation stage. Modulation (or pH cycling) involves the cyclic transformation of ruffle-ended (RE) ameloblasts facing slightly acidic enamel into smooth-ended (SE) ameloblasts near pH-neutral enamel. The mechanism of ameloblast modulation is not clear. Failure of ameloblasts of Cftr-null and anion exchanger 2 ( Ae2)–null mice to transport Cl– into enamel acidifies enamel, prevents modulation, and reduces mineralization. It suggests that pH regulation is critical for modulation and for completion of enamel mineralization. This report presents a review of the major types of transmembrane molecules that ameloblasts express to transport calcium to form crystals and bicarbonates to regulate pH. The type of transporter depends on the developmental stage. Modulation is proposed to be driven by the pH of enamel fluid and the compositional and/or physicochemical changes that result from increased acidity, which may turn RE ameloblasts into SE mode. Amelogenins delay outgrowth of crystals and keep the intercrystalline space open for diffusion of mineral ions into complete depth of enamel. Modulation enables stepwise removal of amelogenins from the crystal surface, their degradation, and removal from the enamel. Removal of matrix allows slow expansion of crystals. Modulation also reduces the stress that ameloblasts experience when exposed to high acid levels generated by mineral formation or by increased intracellular Ca2+. By cyclically interrupting Ca2+ transport by RE ameloblasts and their transformation into SE ameloblasts, proton production ceases shortly and enables the ameloblasts to recover. Modulation also improves enamel crystal quality by selectively dissolving immature Ca2+-poor crystals, removing impurities as Mg2+ and carbonates, and recrystallizing into more acid-resistant crystals.
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Alsar, Zh, B. Duskinova e Z. Insepov. "New Sorption Properties of Diatomaceous Earth for Water Desalination and Reducing Salt Stress of Plants". Eurasian Chemico-Technological Journal 22, n. 2 (30 giugno 2020): 89. http://dx.doi.org/10.18321/ectj955.
Testo completoAbstract (sommario):
A new practical application of the unique sorption abilities of Diatomaceous Earth (DE) or diatomite, a widely accessible and promising natural mineral, has been studied. By analyzing aqueous extracts of natural diatomite, it was shown that DE probably contains various inorganic salts, which are released into the solution in the form of ions, such as Cl-, SO42-, Na+, Ca2+, Mg2+, K+ and, apparently, others. Diatomite was able to exchange these ions with the environment, exhibiting the properties of a natural ion exchanger. Studying the kinetics of ion release from diatomite showed that the ion desorption process continues for 4‒5 h until the surrounding solution is saturated with ions, after which it is dynamically balanced by the sorption process. In order to significantly reduce the ionic content of diatomite, DE samples were processed in a technologically simple and environmentally friendly way. Thus, as a result of deionization, the content of ions released from diatomite significantly decreases. Deionized diatomite was applied to study the adsorption of sodium and chloride ions from aqueous solutions. The maximum adsorption was 50.2 mg/g, and the maximum degree of extraction, corresponding to the concentration range of 5‒100 mg/l, was 53.9%. The observed effect was also applicable for increasing the resistance of plants to salt stress, improving the germination and growth of wheat samples. The developed method can be used in the manufacturing of filters for water desalination, both drinking and technological; in ecology; in agriculture to reduce salt stress of plants, as well as for the restoration of lands contaminated by salt.
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Lai, Zhong-Fang, e Katsuhide Nishi. "Intracellular chloride activity increases in guinea pig ventricular muscle during simulated ischemia". American Journal of Physiology-Heart and Circulatory Physiology 275, n. 5 (1 novembre 1998): H1613—H1619. http://dx.doi.org/10.1152/ajpheart.1998.275.5.h1613.
Testo completoAbstract (sommario):
We investigated the effects of simulated ischemia on intracellular Cl− activity ([Cl−]i) in isolated guinea pig ventricular papillary muscles using ion-selective microelectrode techniques. Simulated ischemia in ventricular muscles was produced by stopping the flow of superfusion and immersing preparations in mineral oil as previously described [B. Vanheel, L. Leybaert, A. De Hemptinne, and I. Leusen. Am. J. Physiol. 257 ( Cell Physiol. 26): C365–C379, 1989; Z. F. Lai, J. Liu, and K. Nishi. Jpn. J. Pharmacol. 72: 161–174, 1996]. When preparations were exposed to paraffin oil for 15 min, [Cl−]imarkedly increased and the peak magnitude of [Cl−]ireached 55.3 ± 2.5 mM from 18.7 ± 3.5 mM, whereas membrane potentials ( V m) depolarized from −82.5 ± 1.1 to −54.7 ± 2.4 mV ( n = 6 muscles from 6 animals). SITS (0.5 mM), a known blocker of the Cl−/[Formula: see text]exchanger, suppressed the ischemia-induced depolarization of V m and delayed the onset of the ischemia-induced increase in [Cl−]ibut did not suppress the magnitude of the increase of [Cl−]i. Under Cl−-free conditions created by replacing Cl−with equimolar gluconate, the increase in [Cl−]iduring ischemia was transient and suppressed by >60% compared with that in normal-Cl− conditions (peak value was 20.3 ± 1.7 mM, n = 6 muscles from 6 animals). The present results provide direct evidence that [Cl−]iin ventricular muscle increases in ischemic conditions in quiescent guinea pig ventricular muscle, suggesting that activation of the Cl−/[Formula: see text]exchanger by ischemia would partially contribute to the elevation of [Cl−]iduring the initial stage of ischemia.
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Novikov, G. V., N. V. Lobus, A. N. Drozdova e Yu P. Dikov. "Sorption of Y 3+, La 3+ AND Се 3+ cations on the cobalt-rich manganese crusts of the Magellan Rise and Marcus-Wake seamounts, Pacific Ocean". Литология и полезные ископаемые, n. 4 (9 luglio 2019): 318–36. http://dx.doi.org/10.31857/s0024-497x20194318-336.
Testo completoAbstract (sommario):
Cobalt-rich manganese crusts and crust-concretion formations from the guyots of the Pacific Ocean were found to be the natural highly selective sorbents of rare-earth cations Ce3+, Y3+, La3+. Ion exchange capacity of ore minerals — vernadite, Fe-vernadite and Mn-ferroxyhyte — increases in the following sequence La3+<Y3+<Co2+<Ce3+ and averages from 1.67 (La3+) to 2.84 (Се3+) meq/g, which is quite high values among natural mineral ion exchangers. Ore minerals of crusts exhibit higher selectivity to Се3+ cation compared to Y3+ и La3+. The age of ore minerals does not affect their sorption with respect to rare earth element cations.
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Dezhatkina, S. V., Sh R. Zyalalov, A. Z. Mukhitov, M. E. Dezhatkin, N. V. Sharonina e V. V. Akhmetova. "Production of organic products in dairy cattle breeding by feeding natural silicon-containing additives". Agrarian science, n. 2 (7 aprile 2021): 45–49. http://dx.doi.org/10.32634/0869-8155-2021-345-2-45-49.
Testo completoAbstract (sommario):
Relevance. Modern livestock breeders face an important task of producing organic products, in Russia this is regulated by the Federal Law “On Organic Products” (from 01.01.2020), it allows producers to enter in the state register and mark the products with the “organic” sign. There is a problem of deterioration of the quality of milk, low content of fat, protein, SOMO, deficiency of macro- and microelements, vitamins, which is associated with a violation of the proper feeding of animals. The use of innovative technologies for the activation and modification of silicon-containing minerals (diatomite and zeolite clinoptilolite) enhances their properties. This makes it possible to use them as an adsorbent, an ion exchanger and a source of readily available silicon and other mineral elements to produce high-quality organic products.Methods. To achieve this goal in the Ulyanovsk region we organized a production experiment in the conditions of a dairy farm of “Agrofirma Tetyushskoe” for a duration of 100 days. Three groups of 50 cows were formed: 1 — control, received only the basic diet (BD), 2 — experimental (BD + supplement based on modified zeolite enriched with amino acids), 3 — experimental (BD + supplement based on modified diatomite enriched with amino acids). The supplement was given once a day in the morning in a mixture with mixed feed, the input rate was 250 g/head/day. For the physiological experiment 5 analog cows were selected in a group. To enrich the minerals a complex of plant-derived amino acids of high purity and biological activity was used.Results. The intake of additives based on silicon-containing natural minerals (zeolite and diatomite), processed with innovative technologies and enriched with plant-based amino acids, increases the level of animal productivity and ensures the yield of organic products of high-quality. It has a prolonging effect.
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Dezhatkina, S. V., V. V. Akhmetova, N. V. Sharonina, L. P. Pulycherovskaya, S. V. Merchina, N. A. Provorova e M. E. Dezhatkin. "New feed additives generation in dairy cattle breeding". Agrarian science, n. 9 (2 novembre 2021): 67–72. http://dx.doi.org/10.32634/0869-8155-2021-352-9-67-72.
Testo completoAbstract (sommario):
Relevance. Modern livestock breeders face an important task of producing organic products, in Russia this is regulated by the Federal Law “On Organic Products” (from 01.01.2020), it allows producers to enter in the state register and mark the products with the “organic” sign. There is a problem of deterioration of the quality of milk, low content of fat, protein, SOMO, deficiency of macro-and microelements, vitamins, which is associated with a violation of the proper feeding of animals. The use of innovative technologies for the activation and modification of silicon-containing minerals (diatomite and zeolite clinoptilolite) enhances their properties. This makes it possible to use them as an adsorbent, an ion exchanger and a source of readily available silicon and other mineral elements to produce high-quality organic products.Methods. To achieve this goal, in the Ulyanovsk region we organized a production experience in the conditions of a dairy farm of “Agrofirma Tetyushskoe” for a duration of 100 days. Three groups of 50 cows were formed: 1st — control, received only the basic diet (ОR), 2nd — experimental (ОR+ supplement based on modified zeolite enriched with amino acids), 3rd — experimental (ОR+ supplement based on modified diatomite enriched with amino acids). The supplement was given once a day, in the morning in a mixture with mixed feed, the input rate was 250 g/head/day. For the physiological experiment, 5 analog cows were selected in a group. To enrich the minerals, a complex of plant-derived amino acids of high purity and biological activity was used.Results The intake of additives based on silicon-containing natural minerals (zeolite and diatomite), processed with innovative technologies and enriched with plant-based amino acids, increases the level of animal productivity and ensures the yield of organic products high-quality. It has a prolonging effect.
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Jantarajit, Walailak, Kornkamon Lertsuwan, Jarinthorn Teerapornpuntakit, Nateetip Krishnamra e Narattaphol Charoenphandhu. "CFTR-mediated anion secretion across intestinal epithelium-like Caco-2 monolayer under PTH stimulation is dependent on intermediate conductance K+channels". American Journal of Physiology-Cell Physiology 313, n. 1 (1 luglio 2017): C118—C129. http://dx.doi.org/10.1152/ajpcell.00010.2017.
Testo completoAbstract (sommario):
Parathyroid hormone (PTH), a pleiotropic hormone that maintains mineral homeostasis, is also essential for controlling pH balance and ion transport across renal and intestinal epithelia. Optimization of luminal pH is important for absorption of trace elements, e.g., calcium and phosphorus. We have previously demonstrated that PTH rapidly stimulated electrogenic [Formula: see text] secretion in intestinal epithelial-like Caco-2 monolayers, but the underlying cellular mechanism, contributions of other ions, particularly Cl–and K+, and long-lasting responses are not completely understood. Herein, PTH and forskolin were confirmed to induce anion secretion, which peaked within 1–3 min (early phase), followed by an abrupt decay and plateau that lasted for 60 min (late phase). In both early and late phases, apical membrane capacitance was increased with a decrease in basolateral capacitance after PTH or forskolin exposure. PTH also induced a transient increase in apical conductance with a long-lasting decrease in basolateral conductance. Anion secretion in both phases was reduced under [Formula: see text]-free and/or Cl−-free conditions or after exposure to carbonic anhydrase inhibitor (acetazolamide), CFTR inhibitor (CFTRinh-172), Na+/H+exchanger (NHE)-3 inhibitor (tenapanor), or K+channel inhibitors (BaCl2, clotrimazole, and TRAM-34; basolateral side), the latter of which suggested that PTH action was dependent on basolateral K+recycling. Furthermore, early- and late-phase responses to PTH were diminished by inhibitors of PI3K (wortmannin and LY-294002) and PKA (PKI 14–22). In conclusion, PTH requires NHE3 and basolateral K+channels to induce [Formula: see text] and Cl−secretion, thus explaining how PTH regulated luminal pH balance and pH-dependent absorption of trace minerals.
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Izci, Ertugrul. "Mineralogical Transformation and Microstructure of the Killik Region Clays". Proceedings of the Bulgarian Academy of Sciences 75, n. 12 (23 dicembre 2022): 1775–84. http://dx.doi.org/10.7546/crabs.2022.12.09.
Testo completoAbstract (sommario):
Killik region (Mihalı¸c¸cık, Eski¸sehir, Turkey) is one of the most important loughlinite clay mineral deposits in Turkey and in the world. Along with loughlinite, analcime and dolomite minerals are also found in this deposit, which is not operable. Anorthoclase (94.61%) and quartz (4.94%) minerals (K2 sample) were obtained as the final product by applying Na ion exchange and thermal exchange processes to the minerals (K1 sample) taken from this deposit. In this study, XRD, Raman and infrared spectroscopies, and SEM techniques were used to characterize the phase structure of the K1 and K2 samples. As a result of this research, obtaining high purity anorthoclase mineral will encourage new research on new usage areas of anorthoclase mineral.
21
Martens, Holger, Sabine Leonhard-Marek, Monika Röntgen e Friederike Stumpff. "Magnesium homeostasis in cattle: absorption and excretion". Nutrition Research Reviews 31, n. 1 (10 gennaio 2018): 114–30. http://dx.doi.org/10.1017/s0954422417000257.
Testo completoAbstract (sommario):
AbstractMagnesium (Mg2+) is an essential mineral without known specific regulatory mechanisms. In ruminants, plasma Mg2+concentration depends primarily on the balance between Mg2+absorption and Mg2+excretion. The primary site of Mg2+absorption is the rumen, where Mg2+is apically absorbed by both potential-dependent and potential-independent uptake mechanisms, reflecting involvement of ion channels and electroneutral transporters, respectively. Transport is energised in a secondary active manner by a basolateral Na+/Mg2+exchanger. Ruminal transport of Mg2+is significantly influenced by a variety of factors such as high K+concentration, sudden increases of ammonia, pH, and the concentration of SCFA. Impaired Mg2+absorption in the rumen is not compensated for by increased transport in the small or large intestine. While renal excretion can be adjusted to compensate precisely for any surplus in Mg2+uptake, a shortage in dietary Mg2+cannot be compensated for either via skeletal mobilisation of Mg2+or via up-regulation of ruminal absorption. In such situations, hypomagnesaemia will lead to decrease of a Mg2+in the cerebrospinal fluid and clinical manifestations of tetany. Improved knowledge concerning the factors governing Mg2+homeostasis will allow reliable recommendations for an adequate Mg2+intake and for the avoidance of possible disturbances. Future research should clarify the molecular identity of the suggested Mg2+transport proteins and the regulatory mechanisms controlling renal Mg excretion as parameters influencing Mg2+homeostasis.
22
Dzyazko, Yuliya, Mariya Chaban e Olga Bystryk. "MATERIALS BASED ON TITANIUM AND MANGANESE OXIDES FOR SELECTIVE RECOVERY OF LITHIUM FROM WATER SOURCES". Ukrainian Chemistry Journal 85, n. 2 (15 febbraio 2019): 88–100. http://dx.doi.org/10.33609/0041-6045.85.2.2019.88-100.
Testo completoAbstract (sommario):
Due to the ever-increasing production of electronic portable devices, including gadgets, lithium recovery is used to produce lithium-ion batteries. Lithium is electrochemically active, has the highest value of oxidation-reducing potential and the highest specific heat capacity among solid materials, making it a key element in the modern revolution of electric vehicles. The crust contains about 0.007% lithium, which is not in its pure form, but its insignificant concentrations are found in virtually all volcanic rocks and in the waters of mineral springs, sea water, and oceans. There are more than 20 minerals that contain lithium, but only few of them have content that is sufficient for commercial interest. A promising area is the processing of brines that are formed after desalination of seawater and mine waters. It is environmentally friendly and cost-effective. Since the concentration of lithium in such resources is low, sorption methods are advantageous compared to other. In this article materials that are widely studied in order to produce lithium-selective adsorbents are described. Most amphoteric oxides and hydroxides are amphoteric ion exchanges having both cation exchange and anion exchange properties. Such materials are of scientific interest in connection with the study of fission fragments behavior, release of radioactive isotopes, decontamination of sewage and concentration of microquantities of elements. The synthesis of such ion exchangers as amphoteric oxides and hydroxides is fairly simple and their cost per unit of capacity in most cases is much lower than the cost of organic resins. The combination of the material formed on the basis of hydrated titanium dioxide with known lithium manganese spinels allows to obtain a strong ion-exchange material for the selective extraction of lithium ions.
23
Zhang, Qian, Xiaohua Shu, Xuetao Guo, Deqing Mo, Shiguang Wei e Chen Yang. "Effect of ions on sorption of tylosin on clay minerals". RSC Advances 6, n. 58 (2016): 53175–81. http://dx.doi.org/10.1039/c6ra07794c.
Testo completo
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Peng, Zhang-kuang, e Zhi-na Liu. "Accurate Determination of Boron Content in Halite by ICP-OES and ICP-MS". International Journal of Analytical Chemistry 2019 (29 maggio 2019): 1–5. http://dx.doi.org/10.1155/2019/9795171.
Testo completoAbstract (sommario):
Boron element is widely distributed in different geologic bodies, and there are important geo-chemical applications in earth science. Halite is a common mineral found in sediment basin. However there is no good method to accurately measure the boron content in halite, which is mainly because Inductively Coupled Plasma Optical Emission Spectrometer (ICP-OES) and Inductively Coupled Plasma Mass Spectrometer (ICP-MS) are limited by the high salt matrix interference and the instrument detection limit. Thus enriching the boron element and removing the matrix interference are necessary before the measuring. In this paper, Amberlite IRA 743 boron-specific resin was applied to enrich the boron element and remove most of the high-salt matrix. The strong acid cation resin (Dowex 50 W×8, 200-400 mesh, USA) and weak-base anion resin (Ion Exchanger II, Germany) were mixed with equal volume, which could remove the foreign ions completely: meanwhile, the relative content of boron in the solution reached above 98%, and the recoveries ranged from 97.8% to 104%. 208.900 nm was chosen as the detection wavelength for ICP-OES, and the detection identification and quantification limits were 0.006 mg·L−1 and 0.02 mg·L−1, respectively. 11B was chosen as the measuring element for ICP-MS, and the detection identification and quantification limits were severally 0.036 mg·L−1 and 0.12 mg·L−1. The relative standard deviations ranged from 1.4% to 3.4% through six replicates under different salinities. Therefore, the process could be regarded as a feasible method to measure boron content in halite by ICP-OES and ICP-MS.
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Bunge, A. L., e C. J. Radke. "The Origin of Reversible Hydroxide Uptake on Reservoir Rock". Society of Petroleum Engineers Journal 25, n. 05 (1 ottobre 1985): 711–18. http://dx.doi.org/10.2118/11798-pa.
Testo completoAbstract (sommario):
Abstract When reservoir solids reversibly consume hydroxide, the impact on alkaline-waterflood performance can be significant. Only recently has this reaction been recognized as a principal factor influencing oil recovery rates and chemical-pulse depletion. This paper considers the origin of the reversible hydroxide uptake to be ion exchange of sodium for hydrogen ions. Using a simple, mass-action equilibrium model, we describe the alkali exchange isotherm. Because hydronium and hydroxide concentrations in water are never zero, hydroxide uptake must be reported relative to a reference pH and salinity. With the recognition of a reference state pH and salinity. With the recognition of a reference state and with the mass-action model, we predict qualitatively the effects of pH, salt concentration, and temperature on the measured hydroxide uptake isotherms for the Wilmington, Ranger-zone sand. Mineral sites that exchange ions of sodium for hydrogen may also exchange calcium for hydrogen or for sodium. Using simple mass-action equilibria again, we demonstrate that reversible hydroxide uptake depends on hardness concentration and that calcium/sodium exchange is pH dependent. Introduction Alkaline flooding is a technique in which chemical interactions with reservoir minerals are of paramount importance to success or failure. Hydroxide consumption falls into three broad categories:reversible rock adsorption or ion exchange,congruent and incongruent mineral dissolution, andprecipitation of insoluble hydroxides. All three loss mechanisms have been considered in various levels of detail. Reversible hydroxide ion uptake, which was overlooked in earlier work on alkali/rock interactions, is, perhaps, the least transparent consumption reaction. Its perhaps, the least transparent consumption reaction. Its existence and importance have come to light only recently. In modeling the alkaline oil recovery process, de Zabala et al. point out that equilibrium hydroxide ion uptake causes a chromographic lag in caustic and in the accompanying in-situ generated surfactants, which in turn slows oil-production rates. Likewise, Bunge and Radke demonstrate that hydroxide ion uptake alone can diminish an alkaline chemical pulse to ineffective concentration levels. Thus, even if caustic consumption by dissolution and precipitation could be eliminated, ion-exchange delay can precipitation could be eliminated, ion-exchange delay can limit the success of alkaline EOR. Therefore, when a reservoir is considered for possible alkaline flooding, understanding and quantifying any alkali/rock ion exchange is necessary. This paper presents a simple, mass-action treatment of reversible hydroxide ion uptake by sodium/hydrogen ion exchange followed by a reaction to form or dissociate water. We refer to this overall reaction scheme as hydroxide uptake, or reversible hydroxide consumption. By using the mass-action model and by paying careful attention to the measurement of alkali exchange isotherms, we show how the effects of pH, salt content, and temperature on the hydroxide uptake isotherms may be explained. The relationship between sodium/hydrogen exchange and calcium/sodium exchange is also explored. We demonstrate that calcium/sodium exchange is a combination of sodium/hydrogen and calcium/hydrogen exchange. Therefore, calcium/sodium exchange isotherms generally must be a function of pH, and hydroxide exchange isotherms must depend on calcium concentration. Finally, the connection between the hydrogen exchange capacity (HEC) and the calcium exchange capacity (CEC) is elucidated. Sodium/Hydrogen Exchange Fig. 1 gives the reversible hydroxide uptake on Wilmington, Ranger-zone sand as a function of hydroxide concentration at three temperatures with and without NaCl. Although there is considerable scatter in the data and few points at the lower pH values, the uptake isotherms appear Langmuir in shape. Also, alkali exchange increases with increasing temperature but decreases when salt is added. Reversible alkali exchange occurs not only with the unconsolidated reservoir materials shown here but also on consolidated Berea sandstone. To quantify the behavior of reversible surface uptake of hydroxide ions on reservoir minerals, we adopt our previous. ture of weak-acid sodium/hydrogen cation previous. ture of weak-acid sodium/hydrogen cation exchange: MOH+Na+ + MONa+H+................... (1) where M represents a mineral exchange site. For oxides (such as silica) MOH denotes a hydrolyzable acid site, while for clay minerals (such as kaolinite or montmorillonite MOH denotes a negative lattice exchange site occupied by a hydronium ion. SPEJ P. 711
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Eichert, Diane, Christèle Combes, Christophe Drouet e Cristian Rey. "Formation and Evolution of Hydrated Surface Layers of Apatites". Key Engineering Materials 284-286 (aprile 2005): 3–6. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.3.
Testo completoAbstract (sommario):
Nanocrystalline apatites exhibit a very fragile structured hydrated surface layer which is only observed in aqueous media. This surface layer contains mobile ionic species which can be easily exchanged with ions from the surrounding fluids. Although the precise structure of this surface layer is still unknown, it presents very specific spectroscopic characteristics. The structure of the hydrated surface layer depends on the constitutive mineral ions: ion exchanges of HPO4 2- ions by CO3 2- ions or of Ca2+ by Mg2+ ions result in a de-structuration of the hydrated layer and modifies its spectroscopic characteristics. However, the original structure can be retrieved by reverse exchange reaction. These alterations do not seem to affect the apatitic lattice. Stoichiometric apatite also shows HPO4 2- on their surface due to a surface hydrolysis after contact with aqueous solutions. Ion exchange is also observed and the environments of the surface carbonate ions seem analogous to that observed in nanocrystalline apatites. The formation of a hydrated layer in aqueous media appears to be a property common to apatites which has to be taken into account in their reactivity and biological behavior.
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Latrille, Christelle, Aubéry Wissocq e Catherine Beaucaire. "Zn sorption on Ca-illite and Ca-smectite: experiment and modelling". E3S Web of Conferences 98 (2019): 04008. http://dx.doi.org/10.1051/e3sconf/20199804008.
Testo completoAbstract (sommario):
To predict Zn behaviour in soil, the retention properties of clay minerals plays a relevant role. In a continental environment, Ca is the main cation in solution. Soil reactivity may be reduced to sorption properties of Zn and Ca on illite and smectite, the major clay minerals in soil. With this assumption, a multi-site ion exchanger model has successfully been applied to the Zn sorption on Ca-illite and Ca-smectite. New batch experiments performed in this study enabled to collect sorption data for Zn on Ca-illite by concentration and pH isotherms. Zn sorption reversibility was then verified. These sorption data were modelled successfully with a multi-site ion exchanger (MSIE) formalism by using four sorption site types. Zn sorption isotherms on smectite were retrieved from literature and interpreted following the MSIE formalism. The obtained selectivity coefficients may be thereafter put into ion exchange models to describe the Zn sorption in natural environments.
28
Singh, S. K., Prashant K. Srivastava, M. Gupta e S. Mukherjee. "Modeling mineral phase change chemistry of groundwater in a rural-urban fringe". Water Science and Technology 66, n. 7 (1 ottobre 2012): 1502–10. http://dx.doi.org/10.2166/wst.2012.338.
Testo completoAbstract (sommario):
This research paper aims to determine the genetic origin of the chemical elements in groundwater. It deals with the results of physicochemical parameters, to evaluate the hydro-geochemistry of groundwater in rural-urban fringe of district Bareilly, India. Pre- and post-monsoon sampling has been carried out, which reveals inter-seasonal variability effect on the hydro-geochemical processes. Geochemical modeling especially computation of saturation index was undertaken using the WATEQ4F model. Majority of samples fall in the category of undersaturation, which further suggests that groundwater still has potential to dissolve more minerals. Chemical categorizations of groundwater samples were performed with the help of the Aquachem model. Grouping of groundwater on the Piper diagram reveals a common composition and origin. In most of the area, water facies is of Ca2+−HCO3− type in both the seasons. It also indicates that in pre-monsoon, ion exchange is the dominant process, whereas in post-monsoon, both ion exchanges as well as reverse ion exchanges are reported in the groundwater of the study area.
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EVANGELOU, V. P., e F. J. COALE. "AN INVESTIGATION ON THE DEPENDENCE OF THE GAPON COEFFICIENT ON EXCHANGEABLE SODIUM BY THREE LINEAR TRANSFORMATIONS". Canadian Journal of Soil Science 68, n. 4 (1 novembre 1988): 813–20. http://dx.doi.org/10.4141/cjss88-080.
Testo completoAbstract (sommario):
Based on theorical considerations of ideal exchangers, the traditional Gapon exchange selectivity coefficient (KG) is generally not expected to remain constant for exchangeable sodium ratio (ESR) greater than 0.20. Therefore, the ESR-SAR (SAR=sodium adsorption ratio) relationship is only expected to be linear and predictable for this limited range of exchange sites. The purpose of this study is to demonstrate that for some soils and/or clay minerals, which are considered nonideal exchangers, the KG may remain constant for ESR values greater than 0.20. This information is important for the reclamation of sodic soil systems with ESR > 0.2 to near Na+ saturation. Experimental data in the literature is most often limited in the ESR range of 0 – 1. Experimental Na+-Ca2+ exchange data for each of a number of soils and clay minerals were plotted according to three linear transformations of the Gapon expression in order to determine if a particular soil or clay mineral exhibits a constant Gapon exchange selectivity coefficient (KG) for ESR values significantly greater than 0.20. The three linear transformations are represented by plots of (1) 1/ExNa vs. 1/SAR, (2) ExNa vs. ExNa/SAR and (3) SAR/ExNa vs. SAR (ExNa = exchangeable Na). From the three plots employed, the ExNa vs. ExNa/SAR and the SAR/ExNa vs. SAR were shown to be the most applicable in predicting a constant KG for ESR values greater than 0.20. It is also shown that some generally low CEC materials may exhibit a constant KG for ESR values significantly greater than 0.20. These data also infer that for a particular soil the linearity of the widely used ESR-SAR relationship introduced by the U.S. Salinity Laboratory Staff may not be limited to an ESR value of 0.20. Key words: Exchangeable sodium percentage, sodium adsorption ratio, thermodynamics of cation exchange, adsorption maxima, ion affinity constants.
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Hasan, Samia S., Zenhom E. Salem e Ahmed Sefelnasr. "Assessment of Hydrogeochemical Characteristics and Seawater Intrusion in Coastal Aquifers by Integrating Statistical and Graphical Techniques: Quaternary Aquifer, West Nile Delta, Egypt". Water 15, n. 10 (9 maggio 2023): 1803. http://dx.doi.org/10.3390/w15101803.
Testo completoAbstract (sommario):
The Quaternary aquifer in the western Nile Delta is threatened by seawater intrusion. Few studies have integrated diverse techniques for the assessment of seawater intrusion in this aquifer. The present study aims to determine the geochemical processes and impact of seawater intrusion on this aquifer. To accomplish this investigation, the integration of hydrogeochemical, statistical, multivariate statistical, and graphical tools were implemented on 75 groundwater samples and 5 soil samples. The physicochemical variables were analyzed using hierarchical cluster analysis (HCA), saturation index (SI), ionic ratios, ionic relationships, the seawater intrusion index (SWI) and the correlations among 16 hydrochemical parameters, to identify the influencing processes of groundwater quality in the study area. According to the statistical study, the groundwater is divided into four groups. Those are distributed, from north to south: Group1 (G1), Group2 (G2), Group4 (G4), and Group3 (G3). The samples of G1 and G2 are distinguished by Na–Cl chemical type. While G4 has two main ion associations, HCO3–Ca–Mg and Cl–SO4–Na, G3 is characterized by HCO3–Cl–SO4–Ca–Na type. The processes that affect the chemistry of the groundwater are the seawater intrusion, ion exchange, silicate and Ca-rich mineral weathering, and mineral deposition. G1 and G2 groups are primarily influenced by seawater incursion, evaporation, and the ion exchange mechanism. In addition, the weathering of silicate minerals has a substantial effect on G3 and G4 groups, resulting in the creation of carbonate minerals.
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Hapis, Abul Ainin, e Mukhlis Sanuddin. "Analisis Spektrofotometri Serapan Atom pada Penjernihan Air Sumur Bor di Desa Sekernan". Jurnal Ilmiah Universitas Batanghari Jambi 22, n. 1 (19 febbraio 2022): 335. http://dx.doi.org/10.33087/jiubj.v22i1.1797.
Testo completoAbstract (sommario):
Cloudy borehole water if done by filtering method with filtration by sand, charcoal, palm fiber, coral and husks can produce clear water. In the purification process can remove turbidity, color, metal Mn about 98.66 % and Fe around 99,50 %. Zeolite is a mineral that is used as an adsorbent, ion exchanger or catalyst. Zeolite in rice husk ash contains high silica content of 87%-97% and coal ash 50%-69% which is used as an ingredient in the manufacture of zeolite. This study aims to determine the zeolite made from rice husk ash and coal can reduce Fe and Mn levels. Based on the test results of the Health Laboratory Office, samples of water from drilled wells in Sekernan village, RT. 11 with the results of Fe content of 0.475 mg/l and Mn content of 0.380 mg/l. The use of borehole water which has a high metal content for drinking water, bathing and washing can cause a person to suffer from stomach ailments such as diarrhea, skin diseases, such as itching and so on. This research is an experimental study. The results of the water filtration process are left for 30-60 minutes. Furthermore, the water was tested for Fe and Mn levels using Atomic Absorption Spectrophotometry (AAS). The results of the AAS analysis showed that the previous Fe level decreased from 0.475 mg/l to < 0.08 mg/l and the previous Mn level was 0.380 mg/l to < 0.03 mg/l. The purification of borehole water with filtration method can produce clear water. Analysis of the AAS test made from zeolite can reduce the metal content of Mn by about 98.66% and Fe by about 99.50%.
32
Hubicki, Zbigniew, Halina Hubicka e Bozena Lodyga. "Studies of the Separation of Palladium(II) Microquantities from Macroquantities of Salts of other Elements on Selective Ion Exchangers". Adsorption Science & Technology 14, n. 1 (febbraio 1996): 5–23. http://dx.doi.org/10.1177/026361749601400102.
Testo completoAbstract (sommario):
The applicability of selective ion exchangers for the removal of palladium(II) from solutions of copper(II), nickel(II), aluminium(III) salts, hydrochloric acid, a mixture of hydrochloric and nitric acids as well as a mixture of hydrochloric acid and ammonium chloride has been studied by frontal analysis. The best results were obtained in the purification of copper(II) and nickel(II) salts on Chelite S with functional thiol groups, Duolite ES-346 with functional amidoxime groups and Lewatit TP-214 with functional thiourea groups. A decrease of palladium(II) content below 5 × 10−5% was obtained in the process of purification of macroquantities of these salts. In addition, these ion exchangers possess a considerable ion-exchange capacity (e.g. 3.18 mequiv. Pd/g for Lewatit TP-214) and a high resistance to mineral acids.
33
Kudryavtsev, G. V., Stanislav Z. Bernadyuk e Georgii V. Lisichkin. "Ion exchangers based on modified mineral carriers". Russian Chemical Reviews 58, n. 4 (30 aprile 1989): 406–19. http://dx.doi.org/10.1070/rc1989v058n04abeh003449.
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Zhang, Guosheng, Na Liu, Yuan Luo, Haibo Zhang, Long Su, Kokyo Oh e Hongyan Cheng. "Efficient Removal of Cu(II), Zn(II), and Cd(II) from Aqueous Solutions by a Mineral-Rich Biochar Derived from a Spent Mushroom (Agaricus bisporus) Substrate". Materials 14, n. 1 (23 dicembre 2020): 35. http://dx.doi.org/10.3390/ma14010035.
Testo completoAbstract (sommario):
This study evaluated the novel application of a mineral-rich biochar derived from a spent Agaricus bisporus substrate (SAS). Biochars with various pyrolysis temperatures (350–750 °C) were used to remove Cu(II), Zn(II), and Cd(II) from aqueous solutions. The adsorption characteristics and removal mechanisms of the biochars were investigated. The adsorption kinetics and isotherm data were fitted well by pseudo-second-order and Freundlich models. The Langmuir maximum removal capacity (Qmax) values of Cu(II), Zn(II), and Cd(II) were ordered as SAS750 > SAS350 > SAS550, and the Qmax values of SAS750 were 68.1, 55.2, and 64.8 mg·g−1, respectively. Overall, the removal mechanisms of biochar at a low production temperature (350 °C) to Cu(II), Zn(II), and Cd(II) were mainly via ion exchange (54.0, 56.0, and 43.0%), and at a moderate production temperature (550 °C), removal mechanisms were mainly via coordination with π electrons (38.3, 45.9, and 55.0%), while mineral precipitation (65.2, 44.4, and 76.3%, respectively) was the dominant mechanism at a high produced temperature (750 °C). The variation of the mutual effect of minerals and heavy metals was the predominant factor in the sorption mechanism of mineral precipitation and ion exchange. The results demonstrated that spent Agaricus bisporus substrate biochar is a potential candidate for the efficient removal of heavy metals, which provides a utilization route for spent mushroom substrates.
35
Colella, C. "Ion exchange equilibria in zeolite minerals". Mineralium Deposita 31, n. 6 (settembre 1996): 554–62. http://dx.doi.org/10.1007/bf00196136.
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Colella, C. "Ion exchange equilibria in zeolite minerals". Mineralium Deposita 31, n. 6 (1 settembre 1996): 554–62. http://dx.doi.org/10.1007/s001260050062.
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Kuczumow, Andrzej, Tomasz Blicharski, Mieczysław Gorzelak, Jakub Kosiński, Agnieszka Lasota, Jacek Gągała, Jakub Nowak, Maciej Jarzębski e Mirosław Jabłoński. "Measurements of Energetic States Resulting from Ion Exchanges in the Isomorphic Crystals of Apatites and Bioapatites". Molecules 27, n. 24 (15 dicembre 2022): 8913. http://dx.doi.org/10.3390/molecules27248913.
Testo completoAbstract (sommario):
Developments in the field of nanostructures open new ways for designing and manufacturing innovative materials. Here, we focused on new original ways of calculating energy changes during the substitution of foreign ions into the structure of apatites and bioapatites. Using these tools, the energetic costs of ion exchanges were calculated for the exemplary cases known from the literature. It was established that the most costly were ion exchanges of some cations inside apatites and of anions, and the least costly exchanges in tetrad channel positions. Real energy expenses for bioapatites are much smaller in comparison to mineral apatites due to the limited involvement of magnesium and carbonates in the structure of hard tissues. They are of the order of several electron volts per ion. The rigorous dependences of the energy changes and crystallographic cell volumes on the ionic radii of introduced cations were proved. The differentiation of the positioning of foreign ions in locations of Ca(I) and Ca(II) could be calculated in the case of a Ca-Pb reaction in hydroxyapatite. The energetic effects of tooth aging were indicated. The ability of energy change calculation during the ion exchange for isomorphic substances widens the advantages resulting from X-ray diffraction measurements.
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Casey, W. H., C. Eggleston, P. A. Johnsson, H. R. Westrich e M. F. Hochella. "Aqueous Surface Chemistry and Corrosion of Minerals". MRS Bulletin 17, n. 5 (maggio 1992): 23–29. http://dx.doi.org/10.1557/s0883769400041245.
Testo completoAbstract (sommario):
Nature is generous with complexity. The number of thermodynamic variables necessary to describe even simple stream chemistry can easily number to a hundred. Nevertheless, research on Earth materials remains exciting because of the vastness of geologic time and the huge scale of global processes. For example, even simple ion-exchange experiments have profound implications when considered in the context of global cycling of elements. Sodium exchange from seawater onto the 1.83 × 1016 g of river-borne clays removes 20–30% of the yearly sodium addition to the ocean. Research on Earth materials, although complex, is rewarding through the scale of the potential result.The surface chemistry of minerals is important for understanding natural mineral transformations and also because surface reactions help control the migration and degradation rates of pollutants in natural waters. These pollutants range from organic herbicides and pesticides, which leak past reactive soil horizons into groundwaters, to acid rain and heavy-metal leaching from mine tailings, sewage sludge, or coal fly ash. The importance of characterizing mineral surface chemistry is clear when one considers that 0.5 to 2% of usable groundwater in the United States is thought to be contaminated.This article reviews some simple surface chemistry of oxide and silicate minerals in water. We focus on the kinetics of mineral corrosion because this subject is interesting to both geochemists and materials scientists. The surface properties that make some solid oxides relatively inert to acid corrosion, for example, are also manifested in the rates of natural mineral weathering.
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Bobreshova, Olga V., Anna V. Parshina e Ksenia A. Polumestnaya. "Potentiometric Multisensory Systems with Novel Ion-Exchange Polymer-Based Sensors for Analysis of Drugs". International Journal of Electrochemistry 2012 (2012): 1–10. http://dx.doi.org/10.1155/2012/392735.
Testo completoAbstract (sommario):
This paper examines potentiometric multisensory systems that consist of novel cross-sensitive PD-sensors (Potential Donnan-sensors). The analytical signal of PD-sensors is the Donnan potential at the ion-exchange polymer/electrolyte test solution interface. The use of novel sensors for the quantitative analysis of multicomponent aqueous solutions of amino acids, vitamins and medical substances is based on protolytic and ion-exchange reactions at the interfaces of ion-exchangers and test solutions. The potentiometric sensor arrays consist of PD-sensors and ion-selective electrodes. Such systems were developed for the multicomponent quantitative analysis of lysine monohydrochloride, thiamine chloride and novocaine hydrochloride solutions that contained salts of alkaline and alkaline-earth metals, as well as for mixed solutions of nicotinic acid and pyridoxine hydrochloride. Multivariate methods of analysis were used for sensor calibration and the analysis of the total response of sensor arrays. The errors of measurement of the electrolytes in aqueous solutions did not exceed 10%. The developed multisensory systems were used to determine the composition of a therapeutic “Mineral salt with low content of sodium chloride” and to determine concentrations of novocaine in sewage samples from a dental clinic.
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Mathur, Ryan, Christopher Emproto, Adam C. Simon, Linda Godfrey, Charles Knaack e Jeffery D. Vervoort. "A Chemical Separation and Measuring Technique for Titanium Isotopes for Titanium Ores and Iron-Rich Minerals". Minerals 12, n. 5 (20 maggio 2022): 644. http://dx.doi.org/10.3390/min12050644.
Testo completoAbstract (sommario):
Ti-isotope fractionation on the most Ti-rich minerals on Earth has not been reported. Therefore, we present a chemical preparation and separation technique for Ti-rich minerals for mineralogic, petrologic, and economic geologic studies. A two-stage ion-exchange column procedure modified from the previous literature is used in the current study to separate Ti from Fe-rich samples, while α-TiO2 does not require chemical separation. Purified solutions in conjunction with solution standards were measured on two different instruments with dry plasma and medium-resolution mode providing mass-dependent results with the lowest errors. 49/47TiOL-Ti for the solution and solids analyzed here demonstrate a range of >5 far greater than the whole procedural 1 error of 0.10 for a synthetic compound and 0.07 for the mineral magnetite; thus, the procedure produces results is resolvable within the current range of measured Ti-isotope fractionation in these minerals.
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Edwin, Rudiawan, Diana Rakhmawaty Eddy, Solihudin e Iman Rahayu. "THE ORGANIC MODIFICATION OF PRE-LITHIATED MONTMORILLONITE". RASAYAN Journal of Chemistry, Special Issue (2022): 167–71. http://dx.doi.org/10.31788/rjc.2022.1558226.
Testo completoAbstract (sommario):
The use of mineral/polyimide composites for lithium-ion battery separators provides an outstanding development direction. Minerals that can be used for lithium-ion battery separators are minerals that have good pores size and distribution, can be intercalated with lithium-ions, and are hydrophobic. Montmorillonite is a natural mineral belonging to the smectite group, and has the capacity to exchange cations but is hydrophilic so it is necessary to modify it to make it hydrophobic and to keep it rich in lithium ions for such purpose. In this study, organic modification has been carried out to change the hydrophilic nature of montmorillonite to become hydrophobic under lithium-ion-rich conditions. Montmorillonite was first isolated by sonicating the dispersion, then carefully separating its suspension after several days of aging. Afterward, the suspension was precipitated by centrifugation and finally dried at 80°C. Thereafter, carbonate cations, organic compounds, and metal oxides, especially ferrous oxide, are removed. The purified isolated montmorillonite is then lithiated with lithium chloride. Finally, the surface of the pre-lithiated montmorillonite was modified with cetyltrimethylammonium bromide to obtain organic-modified pre-lithiated montmorillonite. The results of characterization with an infrared spectrophotometer showed vibration peaks at 2928 cm-1, 2854 cm-1, and 1476 cm-1 as evidence of the presence of attached cetyltrimethylammonium, and vibration peaks at 520 cm-1 and 463 cm-1 as evidence of the presence of attached lithium. The results were also characterized by SEM and XRD which shows that the montmorillonite was organically modified, and lithium intercalated.
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Khramtsov, A. G. "Technological breakthrough of the agrarian-and-food innovations in dairy case for example of universal agricultural raw materials. Ion exchange". Agrarian-And-Food Innovations 16 (29 dicembre 2021): 7–19. http://dx.doi.org/10.31208/2618-7353-2021-16-7-19.
Testo completoAbstract (sommario):
Aim. Consideration of the process of membrane technology – ion exchange by directed and controlled processing of whey and its filtrates through specially selected selective sorbents – ion exchange resins (ionites). Discussion. The essence of ion exchange lies in the fact that, under certain conditions, an exchange of ions takes place between a solid (ion-exchange resin) and a solution containing undesirable impurities, as a result of which the solid sorbs the ion from the solution, giving it also an ion less harmful to the basic manufacturing. Ion exchange allows to remove some undesirable mineral and organic compounds of the ionic and molecular origin of whey and its filtrates (permeates). Conclusion. The use of ion exchange for the processing of universal agricultural raw materials is recommended for the production of high-quality milk sugar (lactose) by spray drying, dry whey for baby food, synthesis and demineralization of lactulose syrups; sorption-desorption of whey proteins.
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Umirova, Nilufar. "Use of glauconite as a non-reagent sorbent for the softening of drinking and boiler waters, industrial waste water". E3S Web of Conferences 216 (2020): 01147. http://dx.doi.org/10.1051/e3sconf/202021601147.
Testo completoAbstract (sommario):
The article discusses the sorption of purification of water bodies from impurities using natural inorganic sorbents. The availability and low cost of minerals are an important economic advantage of their use for the purification of all types of water. The article describes a method of using an effective sorbent with high ion-exchange and sorption properties for purification of light oil products, for the purification of drinking or industrial water with a high content of heave technogenic metal ions and organic substances. Based on the data obtained, conclusions are drawn about the possibility of using the studied natural mineral sorbents for the extraction of impurities from waste and natural waters.
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Rockley, N. L., e M. G. Rockley. "The FT-IR Analysis by PAS and KBr Pellet of Cation-Exchanged Clay Mineral and Phosphonate Complexes". Applied Spectroscopy 41, n. 3 (marzo 1987): 471–75. http://dx.doi.org/10.1366/0003702874448797.
Testo completoAbstract (sommario):
A comparison is made between the KBr pellet and FT-IR/PAS spectra of a series of interlamellar-cation-exchanged montmorillonites. Spectra of these clay minerals after adsorption of dimethyl methylphosphonate are also compared by the two spectroscopic methods. It is shown that the two infrared methods yield complementary spectral information, while FT-IR/PAS produces spectra with better definition of the adsorbate bands in all cases and superior reliability for observation of interlamellar ion-induced spectral shifts. Dimethyl methylphosphonate is shown to undergo interlamellar insertion, with bonding occurring directly through the P=0 moiety to the cation of the clay mineral. The strength of the bonding varies with the charge density of the cation.
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Panikorovskii, Taras L., Victor N. Yakovenchuk, Nataliya Yu Yanicheva, Yakov A. Pakhomovsky, Vladimir V. Shilovskikh, Vladimir N. Bocharov e Sergey V. Krivovichev. "Crystal chemistry of ivanyukite-group minerals, A3–xH1+x[Ti4O4(SiO4)3](H2O)n (A = Na, K, Cu), (n = 6–9, x = 0–2): crystal structures, ion-exchange, chemical evolution". Mineralogical Magazine 85, n. 4 (7 giugno 2021): 607–19. http://dx.doi.org/10.1180/mgm.2021.51.
Testo completoAbstract (sommario):
AbstractMicroporous slicates with the pharmacosiderite structure and the general formula A3–xH1+x[Ti4O4(SiO4)3](H2O)n (A = Na, K, Cu), (n = 6–9, x = 0–2) are outstanding in their ion-exchange properties. The ivanyukite mineral group consists of three species, one of which has two polymorphs. The minerals forming a progressive series: ivanyukite-Na-T → ivanyukite-Na-C → ivanyukite-K → Cu-rich ivanyukite-K → ivanyukite-Cu, have been studied by single-crystal X-ray diffraction, electron microprobe analysis and Raman spectroscopy. The microporous heteropolyhedral framework of the ivanyukite-group minerals is based on cubane-like [Ti4O4]8+ clusters that share common corners with SiO4 tetrahedra to form wide three-dimensional channels suitable for the migration of Na+, K+ and Cu2+ ions. Ivanyukite-Na-T that has a R3m symmetry loses Na+ in aqueous solutions via the substitution Na+ + O2‒ ↔ □ + OH‒, which allows for the migration of K+ ions and transformation of initial structure into the cubic (P$\bar{4}3m$) ivanyukite-Na-C polymorph or into ivanyukite-K, when most of Na is lost. Natural ivanyukite-Na-C is shown to contain domains of both R3m (subordinate) and P$\bar{4}3m$ (dominant) symmetry with the chemical composition determining the stability and dominance of cubic or trigonal forms. Incorporation of Cu into the crystal structure ivanyukite-K via the substitution K+ + OH− ↔ Cu2+ + O2− in aqueous solutions results in the formation of ivanyukite-Cu. Post-crystallisation processes (such as exchange of Na+, K+, Cu2+, and/or hydration/dehydration of primary phases) are widespread in hyperagpaitic rocks of the Kola alkaline massif and the respective mineral transformations contribute to the diversity of mineral species.
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Ivanenko, Vladimir I., Roman I. Korneykov e Nikita V. Zharov. "Justification of the prospects of using phosphatotitanium ion exchangers for extracting rare earth metals from solutions of radionuclides". Butlerov Communications 59, n. 9 (30 settembre 2019): 58–65. http://dx.doi.org/10.37952/roi-jbc-01/19-59-9-58.
Testo completoAbstract (sommario):
The results of a study of the sorption properties of ion-exchange materials based on hydrated titanium (IV) oxohydroxophosphates with respect to rare-earth metal cations are presented in this paper. A high affinity of the latters for the sorption matrix in nitrate media was established, which is determined by the ion radius of the sorbate and increases in the series Y3+ Gd3+ Eu3+ Sm3+ Nd3+ Ce3+ at pH=4 and La3+ Ce3+ Y3+ Yb3+ at pH=1.5 for all the studied sample compositions. It was experimentally shown that the doping of sorbents based on titanium (IV) oxyhydroxophosphates with zirconium (IV) cations, which differs from titanium (IV) in acid-base properties, leads to an increase in the sorption properties of ion exchangers, which allows the use of modified compositions for sorption of rare-earth metal cations from solutions with high acidity. It was established that partial dehydration of the sorption matrix and increase in temperature increase the sorption ability of ion-exchange materials. Sorption extraction of rare-earth element cations by sorbents of various compositions was carried out from solutions simulating real technological objects generated during the processing of nuclear fuel waste. It is shown that sorption materials based on hydrated titanium (IV) oxohydroxophosphates are promising ion exchangers for the extraction of rare-earth element cations from technological solutions with complex chemical composition. It was established that unmodified sorbent compositions are promising for the selective extraction of rare-earth element cations, while modified compositions are of interest for group sorption. The thermal treatment of a sorbent saturated with radioisotopes leads to the formation of crystalline insoluble mineral-like compounds, which ensures reliable immobilization of the sorbed components during long-term storage of the spent product.
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Mohammed, Isah, Dhafer Al Shehri, Mohamed Mahmoud, Muhammad Shahzad Kamal, Olalekan Alade, Muhammad Arif e Shirish Patil. "Effect of Native Reservoir State and Oilfield Operations on Clay Mineral Surface Chemistry". Molecules 27, n. 5 (7 marzo 2022): 1739. http://dx.doi.org/10.3390/molecules27051739.
Testo completoAbstract (sommario):
An understanding of clay mineral surface chemistry is becoming critical as deeper levels of control of reservoir rock wettability via fluid–solid interactions are sought. Reservoir rock is composed of many minerals that contact the crude oil and control the wetting state of the rock. Clay minerals are one of the minerals present in reservoir rock, with a high surface area and cation exchange capacity. This is a first-of-its-kind study that presents zeta potential measurements and insights into the surface charge development process of clay minerals (chlorite, illite, kaolinite, and montmorillonite) in a native reservoir environment. Presented in this study as well is the effect of fluid salinity, composition, and oilfield operations on clay mineral surface charge development. Experimental results show that the surface charge of clay minerals is controlled by electrostatic and electrophilic interactions as well as the electrical double layer. Results from this study showed that clay minerals are negatively charged in formation brines as well as in deionized water, except in the case of chlorite, which is positively charged in formation water. In addition, a negative surface charge results from oilfield operations, except for operations at a high alkaline pH range of 10–13. Furthermore, a reduction in the concentrations of Na, Mg, Ca, and bicarbonate ions does not reverse the surface charge of the clay minerals; however, an increase in sulfate ion concentration does. Established in this study as well, is a good correlation between the zeta potential value of the clay minerals and contact angle, as an increase in fluid salinity results in a reduction of the negative charge magnitude and an increase in contact angle from 63 to 102 degree in the case of chlorite. Lastly, findings from this study provide vital information that would enhance the understanding of the role of clay minerals in the improvement of oil recovery.
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Krebs, R., M. Sardin e D. Schweich. "Mineral dissolution, precipitation, and ion exchange in surfactant flooding". AIChE Journal 33, n. 8 (agosto 1987): 1371–78. http://dx.doi.org/10.1002/aic.690330814.
Testo completo
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Malamis, S., E. Katsou, M. Stylianou, K. J. Haralambous e M. Loizidou. "Copper removal from sludge permeate with ultrafiltration membranes using zeolite, bentonite and vermiculite as adsorbents". Water Science and Technology 61, n. 3 (1 febbraio 2010): 581–89. http://dx.doi.org/10.2166/wst.2010.859.
Testo completoAbstract (sommario):
The aim of this work is to examine copper removal from sludge permeate with the use of low-cost minerals of Mediterranean origin combined with ultrafiltration membranes. The minerals used were zeolite (clinoptilolite), bentonite and vermiculite. Activated sludge was enriched with 0.01 N (317.7 ppm) of Cu(II). Fixed concentrations of minerals were added to sludge and the pH value was adjusted at 5.5. The mixture was agitated for 2 hours at 800 rpm at room temperature and was then filtered through a batch ultrafiltration system for 1 hour. This experiment was repeated, for comparison purposes, with sludge enriched with 0.01 N of Cu(II) with no mineral addition. The results showed that ultrafiltration membranes with no mineral addition were able to remove a significant amount of copper with removal efficiencies ranging from 59.4–78.3%. The addition of 10 g/l and 20 g/l of bentonite combined with ultrafiltration membranes resulted in removal efficiencies of 94.9% and 99.4% respectively and that of 10 g/l and 20 g/l of vermiculite in removal efficiencies of 93.8% and 96.8%, respectively. The ion exchange capacity of minerals followed the order bentonite > vermiculite > zeolite. Furthermore, membrane fouling was investigated. The addition of zeolite and bentonite reduced membrane fouling, while the addition of vermiculite did not impact on fouling. The use of low-cost minerals in combination with ultrafiltration membranes can be employed to treat industrial wastewater, resulting in a final effluent with very low copper concentrations.
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Matijasevic, Srdjan, Aleksandra Dakovic, Deana Iles e Sonja Milicevic. "Adsorption of uranyl ion on acid-modified zeolitic mineral clinoptilolite". Chemical Industry 63, n. 5 (2009): 407–14. http://dx.doi.org/10.2298/hemind0905407m.
Testo completoAbstract (sommario):
In this paper, the results of adsorption of uranyl ion on acid-modified zeolitic mineral clinoptilolite are presented. Adsorption was investigated at different amounts of solid phase in suspension, as well as at different pH values. The modified clinoptilolite samples were obtained by treatment of clinoptilolite with acids: hydrochloric, oxalyc and citric. Starting and modified clinoptilolites were characterized by chemical analysis, thermal (DT/TG) analysis and by determination of cation exchange capacity, while starting and nonadsorbed amounts of uranyl ion were determined by fluorometric method. Uranyl ion adsorption experiments on natural unmodified zeolitic mineral showed that uranyl ion adsorption was low (29.2%) and that treatment of clinoptilolite with acids significantly increases the adsorption of uranyl ion (>90%). In the case of acid treated clinoptilolites, the highest adsorption of uranyl ion was achieved on clinoptilolite modified with hydrochloric acid. Kinetics of adsorption showed that adsorption of uranyl ion begins very fast and that the most of uranyl ion was adsorbed in first 30 min. Practically, there were no changes in uranyl ion adsorption within next 72 h.