Dissertations / Theses on the topic 'Magnetic anion exchange resin'

The increasing awareness towards PFAS pollution makes it increasingly important to treat. Many agencies over the globe, including the Swedish Food Agency, are introducing ever so strict control over PFASs in drinking water. One of Norrvatten’s back-up drinking water plants, the Hammarby plant, is a groundwater plant that saw elevated concentrations of PFASs (sum of 32 PFASs~80 ng/L) and total uranium (~109 µg/L). The aim of this work is to investigate the possible remediation for PFAS and uranium pollution in the groundwater. The main objective is to examine the possibility of SorbixTM, a strong-base anion exchange resins provided by ETC2, adsorbing PFAS and uraniumfrom the groundwater. Furthermore, the optimal solution of groundwater and sodium chloride that prevents microbial growth is to be investigated. This is of interest considering the intermittent operation of the Hammarby plant, where water would be allowed to stagnant for longer periods thus being prone to microbial growth. The effect of microorganisms on the resins is of concern. Biogrowth experiments were conducted using four different brines: 0%, 5%, 15%, and 25%. Identical masses of AIX resins were soaked in these solutions for 19-29 days in order to investigate whether the brine is effective at inhibiting biogrowth. The tests were analyzed mainly using plate count method, and secondly using flow cytometry. For uranium and PFAS removal, batch experiments using (1) resins that were previously soaked in brine were performed, (2) resins that were exposed to microorganisms as well as (3) new unused resins. Results showed that brines with 15% salinity or higher are capable of completely stopping microbial growth. The SorbixTM was capable of removing PFAS to below detection levels, as well as 99% removal of total uranium. To further develop on this study, column experiments with continuous water flow should be investigated. Continuous flow is a more accurate representation of the real case and will give knowledge on additional information regarding the breakthrough volume of the individual PFASs, the required water flow relative to available resin area that ensures acceptable removals, and how the competitiveness of uranium affects PFAS adsorption. It is also recommended to investigate the potential for regenerating the AIX resins. The Swedish Food Agency restricts the chemicals that are allowed to come in contact with any drinking water equipment. This means that some of the regenerative substances used in other studies are prohibited in Sweden.<br>Den växande uppmärksamheten kring PFAS gör det allt viktigare att avlägsna dessa från dricksvatten. Flera myndigheter över hela världen, inklusive Livsmedelsverket, inför gränsvärden och kontroller på PFAS i dricksvatten som blir allt striktare. En av Norrvattens reservvattenverk, Hammarby, är en grundvattenanläggning som visade förhöjda koncentrationer av PFAS och uran, där summan av de 32 mest förekommande PFASs är 80 ng/L och den totala uranhalten är 109 µg/L. Syftet med detta arbete är att undersöka möjligheten till PFAS och uran borttagning från grundvattnet. Huvudmålet är att undersöka möjligheten för SorbixTM, en starkbasisk anjonbytesharts som är framtagen av ETC2 Sverige (ETC2, n.d.), att adsorbera PFAS och uran från grundvattnet. Dessutom ska den optimala lösningen av grundvatten och natriumklorid, som förhindrar mikrobiell tillväxt, undersökas. Detta är av intresse med tanke på den intermittenta driften av Hammarby-anläggningen, där vattnet i ledningarna är stillastående under längre perioder och därmed blir utsatt för mikrobiell tillväxt. Effekten av mikroorganismer på jonbytesharts är, enligt andrastudier, bekymmersam. Tillväxtexperimenten utfördes genom användning av fyra olika saltlösningar: 0%, 5%, 15%och 25%. Identiska massor av anjonbytesharts blötlades i dessa lösningar i 19-29 dagar för att undersöka biologisk tillväxt. Testerna analyserades huvudsakligen med tre-dagars-tillväxt och imindre utsträckning med flödescytometri.För uran- och PFAS-avlägsnande så användes standardiserad skaktester med (1) jonbytesharts somtidigare blötlagts i saltvatten, (2) jonbytesharts som exponerats för mikroorganismer samt (3) nytt och oanvänt jonbytesharts. Resultatet visade att lösningar med 15% salthalt eller högre kan bromsa den mikrobiella tillväxten helt. SorbixTM lyckades ta bort PFAS till under detektionsnivåer, samt avlägsnade över 99% av den uppmätta uranen i grundvattnet. För vidare studier så rekommenderas kolonnförsök med kontinuerligt vattenflöde. Kontinuerligt flöde är en mer exakt representation av det verkliga fallet och kommer att ge ytterligare information såsom: breakthrough volymen för de enskilda PFASs, optimala vattenflödet i förhållande till tillgänglig yta av jonbytesharts som säkerställer acceptabel avlägsnande samt hur stark konkurrensen mellan uran och PFAS blir och vilken av de som adsorberas/desorberas först. Dessutom rekommenderas undersökningar på regenereringen av jonbytesharts, med tanke till de begränsade regenereringsämnen som är tillåtna enligt Livsmedelsverket. Många regenerativa ämnensom används i andra studier är förbjudna att använda i Sverige.

This study focuses on the development of novel two-stage esterification-transesterification synthesis of biodiesel from used cooking oil (UCO) using novel heterogeneous catalysts. The esterification of the UCO was investigated using three types of ion exchange resins catalysts including Purolite D5081, Purolite D5082 and Amberlyst 15. Of all the catalysts investigated, Purolite D5081 resin showed the best catalytic performance and was selected for further optimisation studies. From the optimisation study, it was found that the external and internal mass transfer resistance has negligible effect on the esterification reaction. At the optimum reaction conditions, Purolite D5081 achieved 92% conversion of FFA. During reusability study, the conversion of FFA dropped by 10% after each cycle and it was found that progressive pore blockage and sulphur leaching were dominant factors that decreased the catalytic performance of the Purolite D5081 catalyst. A kinetic modelling for FFA esterification was carried out using Purolite D5081 as a catalyst. Three types of kinetic models were investigated i.e. pseudo homogeneous (PH), Eley-Rideal (ER) and Langmuir-Hinshelwood-Hougen-Watson (LHHW). Experimental data obtained from the batch kinetic studies was successfully represented by the PH model and a good agreement between experimental and calculated values was obtained. The activation energy for esterification and hydrolysis reaction was found to be 53 and 107 kJ/moL. The transesterification of pre-treated cooking oil (P-UCO) was investigated using various types of heterogeneous catalysts including Purolite CT-122, Purolite CT-169, Purolite CT-175, Purolite CT-275, Purolite D5081, Diaion PA306s and Cs-supported heteropolyacids catalysts. Of all the catalysts investigated, Diaion PA306s catalyst showed the highest conversion of triglycerides and was selected for further optimisation studies. At the optimum reaction conditions, Diaion PA306s achieved ca. 75% of triglycerides conversion. During the reusability study, Diaion PA306s catalyst gave a similar conversion of triglycerides after being reused once. Therefore, it was concluded that the resin can be used several times without losing catalytic activity. Several purification methods have been investigated and dry washing method was chosen as the best alternative for biodiesel purification.

Não há dúvidas que a exitosa exploração do Cerrado só foi possível graças às pesquisas que desenvolveram tecnologias de correção e adubação específicas para esse ambiente. Apesar de estar consolidado como um dos principais ambientes de produção agropecuária do mundo, as pesquisas devem avançar contribuindo, cada vez mais, com aumento na eficiência do uso do fósforo (P), por ser o elemento mais limitante para produção agrícola nesse ambiente. Devido às características dos solos dessa região, parte do P aplicado é retido pelo solo em formas que as plantas não conseguem absorver, resultando na acumulação de quantidades significativas do nutriente no solo. Apesar de não ser um assunto relativamente novo e do grande número de trabalhos, o tema avaliação da disponibilidade de fósforo do solo ainda provoca dúvidas. Além dos estudos em que é avaliada a eficiência de diversos extratores como Mehlich-1 e resina de troca aniônica, outras técnicas passaram a ser utilizadas para esse fim. Estudos objetivando avaliar a distribuição (dinâmica) do fósforo nas diferentes frações do solo e as mudanças nessa distribuição em função do manejo aplicado aos cultivos e, também, do tempo de cultivo, têm sido conduzidos com crescente intensidade. Estudos também têm sido conduzidos buscando identificar as formas de acumulação de P no solo. Para isso, modernas técnicas espectroscópicas, como por exemplo, a espectroscopia baseada em luz synchrotron, têm sido utilizadas como uma poderosa ferramenta, auxiliando na identificação dos compostos presentes no solo. Face ao exposto, objetivou-se avaliar as alterações no fósforo disponível e nas frações e formas de fósforo em solo de Cerrado submetido ao manejo em semeadura direta com diferentes tempos de cultivo. Foram coletadas amostras compostas em quatro áreas que se encontravam no momento da coleta com 5, 8, 12 e 18 anos de cultivo desde a abertura das áreas, e também numa área sob vegetação nativa. O fósforo disponível foi extraído por Mehlich-1 e resina de troca aniônica. As amostras foram submetidas ao fracionamento químico de fósforo e espectroscopia de alta resolução da borda de absorção (XANES - X-ray absorption near edge structure). Observou-se que, de maneira geral, os teores de fósforo no solo foram sempre mais altos nas áreas cultivadas, principalmente na camada superficial, em comparação aos da área com vegetação nativa, o que reflete o impacto das adubações fosfatadas. A aplicação superficial do fertilizante fosfatado gerou nítidos gradientes de P no perfil do solo, principalmente para as frações lábeis e moderadamente lábeis, sendo essas frações as que sofreram maior influência do fertilizante quando comparadas às frações de menor disponibilidade. Considerando-se os mesmos extratores, os teores das frações orgânicas foram maiores em comparação às correspondentes frações inorgânicas. As formas de fósforo nos solos estudados foram predominantemente associadas ao alumínio e ao ferro, com destaque para o nutriente associado ao alumínio, sendo que, com o ferro, a associação ocorreu predominantemente por meio de fenômenos de adsorção em detrimento de fenômenos de precipitação.<br>There is no doubt that the successful exploitation of the Cerrado was only possible due to the research that developed specific correction and fertilization technologies to this particular environment. Due to the characteristics of soils in the region, part of applied phosphorus (P) is retained by the soil in plant unavailable forms, resulting in accumulation of significant amounts of nutrient in the soil. Despite not being a relatively new issue and the large number of research performed on this topic, the assessment of the soil P availability still raise important questions. In addition to studies in which the efficiency of various extractants have been tested, such as Mehlich-1 and anion exchange resin, other techniques are being used for this purpose. Studies for evaluating the P distribution (dynamic) in different soil fractions and the changes in this fractions due to the management applied to crops and also the time of cultivation have been conducted with increasing intensity. Studies have also been carried out in order to identify the forms of P accumulation in soils. For this purpose, modern spectroscopic techniques such as spectroscopy based on synchrotron light source, have been used as a powerful tool, assisting in the identification of P compounds presents in the soil. The aims of this study were to evaluate the changes in available, fractions and forms of P in soils of Cerrado with different times under no-till cultivation system. Composite soil samples were collected in four areas under 5, 8, 12 and 18 years of no-till cultivation since the areas were opened, and also in a area under native vegetation. The soil in the area was classified as Typic Hapludox and the areas were cultivated alternating crops of soybeans, corn and cotton. Available P was extracted by Mehlich - 1 and anion exchange resin. The samples were subjected to Hedley´s chemical fractionation of P and X- ray absorption near edge structure (XANES). It was observed that, in general, the levels of P in the soil were always higher in cultivated areas, mainly in the topsoil, when compared to the area under native vegetation, which reflects the impact of phosphate fertilization. Surface application of phosphate fertilizer produced sharp gradients of P in the soil profile, especially for both labile and moderately labile fractions, and these fractions suffered the greatest influence of fertilizer compared to fractions of lower availability. Considering the same extractants, the organic P fractions contents were higher compared to the corresponding inorganic fractions. Forms of phosphorus in soils were predominantly associated with aluminum (Al) and iron (Fe), especially P associated with Al, and with Fe the association occurred predominantly through adsorption phenomenon rather than precipitation reactions.

Le son et la paille de blé, riches en hémicelluloses, sont deux co-produits de la récolte de blé, abondants et renouvelables, mais qui restent à mieux valoriser. Dans le but d'extraire ces hémicelluloses, possédant plusieurs propriétés intéressantes (filmogènes, épaississantes, émulsifiantes, stabilisantes…), un procédé de fractionnement a été élaboré. Ce procédé consiste, après extraction alcaline, en la purification des extraits hémicellulosiques obtenus. Deux techniques ont été appliquées : l'ultrafiltration et la chromatographie sur résine échangeuse d'anions. L'ultrafiltration a permis de concentrer les extraits d'hémicelluloses et de les purifier en éliminant dans le perméat la plupart des molécules contaminantes, essentiellement les sucres libres et les sels minéraux. Les principales limitations de cette étape étaient la viscosité des extraits et les phénomènes de polarisation de concentration et de colmatage des membranes. La percolation sur résine, quant à elle, a permis de décolorer les extraits et de produire des poudres d'hémicelluloses plus claires en fixant certaines molécules colorées telles que les molécules possédant des groupements phénoliques. La combinaison des deux techniques a permis de produire des hémicelluloses pures à 60%. L'extrapolation du procédé à l'échelle pilote par l'utilisation d'un extrudeur bi-vis a permis d'obtenir des poudres d'hémicelluloses pures à 40%<br>Wheat bran and wheat straw are two by-products abundant and renewable, rich in hemicelluloses, but still not well valued. In order to extract these hemicelluloses characterized by their several interesting properties (film-forming, thickening, emulsifying, stabilizing…), a fractionation process was developed. This process consisted, after alkaline extraction, to purify the hemicellulosic extracts obtained. Two techniques were used: ultrafiltration and chromatography on anion exchange resin. The ultrafiltration allowed to concentrate the extracts and to purify them by removing in the permeate, the contaminating molecules, mostly free sugars and minerals. The main limiting factors of this stage were the extracts viscosity and the fouling of the membranes. The percolation on the resin discoloured the extracts and allowed to produce hemicellulosic powders with lighter colours and that by capturing the coloured compounds such as molecules with phenolic groups. The combination of the two techniques allowed the production of purified hemicelluloses; the purity was about 60%. The extrapolation of the process at a pilot scale using a twin-screw extruder allowed to obtain hemicelluloses with a purity of 40%

Die vorliegende Arbeit beschäftigt sich mit der Herstellung von funktionellen Magnetit-Nanokompositen durch Sprühtrocknung für die Anwendung in der Bioseparation. Dabei liegen die Schwerpunkte auf der Anwendung von Polyelektrolyten als Ionenaustauscher sowie auf der Nachhaltigkeit des Herstellungsprozesses. Basierend auf einem existierenden Herstellungsprozess wurde die Aufgabenstellung konkretisiert. Es wurden Möglichkeiten zur nachhaltigen Prozessgestaltung der Synthese von kationischen bzw. anionischen magnetischen Funktionspartikeln zur Proteinabtrennung vorgestellt. Als magnetische Komponente wurde Magnetit verwendet. Aufgrund seines pseudo-amphiphilen Charakters und seiner besonderen Eigenschaften in Bezug auf die Stabilisierung von Magnetit-Kolloiden wurde Polyvinylbutyral (Mowital B 30T) als Matrixpolymer bei der Sprühtrocknung benutzt. Für die nachhaltige Prozessgestaltung wurden Isopropanol und Tetrahydrofuran als Dichlormethan-Ersatz bei der Sprühtrocknung verwendet. Bei der Synthese kationischer Magnetic Beads wurden verzweigtes Polyethylenimin und lineares Poly(Allyamin) als Anionenaustauscher verwendet. Beide Polykationen sind schwache Polyelektrolyte mit Aminogruppen. Für die Verarbeitung der Polykationen als funktionelle Liganden in magnetischen Funktionspartikeln wurde zwei Herstellungsmethoden vorgestellt: eine Synthese ohne Oberflächenmodifizierung, wobei die mechanische und chemische Stabilität der Funktionspartikeln einzig von der chemischen Struktur der eingesetzten Materialien bzw. vom Matrixpolymer abhängt, und eine Synthese mit Oberflächenmodifizierung. Die Synthese mit Oberflächenmodifizierung ist gekennzeichnet durch die kovalente Bindung von Polyethylenimin bzw. Poly(Allyamin) an der Oberfläche der Funktionspartikeln (Polyvinylbutyral). Dafür wurde 1,1’-Carbonyldiimidazol als „zero length“-Crosslinker benutzt. Die nach beiden Methoden hergestellten Funktionspartikeln wurden charakterisiert, um ihre technische Eignung beurteilen zu können. Für die Charakterisierung der sorptiven Eigenschaften wurde unter anderem der Bowman-Birk Inhibitor (BBI) verwendet. Das Protein ist ein Sojaprodukt und für seine krebsvorbeugende Wirkung bekannt. Um die Selektivität der Abtrennung zu untersuchen, wurden BBI-Produkte mit unterschiedlichen Reinheitsgraden benutzt. Durch die zwei vorgestellten Methoden konnten kationische magnetische Funktionspartikeln erfolgreich hergestellt werden. Alle Funktionspartikeln sind superparamagnetisch, und der Medianwert ihrer Partikelgrößenverteilung liegt im einstelligen Mikrometerbereich. Aufgrund eines höheren Polykationanteils ist die Bindungskapazität der Funktionspartikeln ohne Oberflächenmodifizierung um den Faktor 2,4 größer als die BBI-Bindungskapazität der Funktionspartikeln mit Oberflächenmodifizierung (Qmax=322 mg/g). Das Fehlen eine feste Anbindung des funktionellen Liganden an den Funktionspartikeln ohne Oberflächenmodifizierung verleiht jedoch diesen eine sehr schlechte chemische Stabilität in Lösungen. Es wurde auch gezeigt, dass oberflächenmodifizierte Funktionspartikeln mit ähnlichen Eigenschaften durch den Einsatz von Dichlormethan bzw. Tetrahydrofuran als Lösungsmittelersatz während der Sprühtrocknung hergestellt werden können. Durch den Einsatz von mit Poly(allylamin) oberflächenmodifizierten Funktionspartikeln konnte BBI von technischen Sojamolken unterschiedlicher Reinheitsgrade erfolgreich abgetrennt werden. Anionische Magnetic Beads wurden mit Kationenaustauscherharz als funktionellem Ligand hergestellt. Dabei wurde Isopropanol als organisches Lösungsmittel während der Sprühtrocknung verwendet. Die Synthese wurde analog zur Synthese der kationischen Magnetic Beads ohne Oberflächenmodifizierung durchgeführt. Es wurde auch hier gezeigt, dass anionische magnetische Funktionspartikeln mit guten sorptiven Eigenschaften durch den Einsatz von Isopropanol als organisches Lösungsmittel hergestellt werden können. Die anionischen Funktionspartikeln besitzen im Vergleich zu Literaturwerten höhere Bindungskapazitäten (bis 280 mg/g; ermittelt mit Lysozym). Im letzten Kapitel wird der kritische Prozessschritt des Lösungsmittelaustausches behandelt. Nach dem Lösungsmittelaustausch sollten die Magnetitnanopartikeln in der organischen Phase stabil sein. Dies ermöglicht sowohl eine homogene Verteilung der Nanopartikeln in der Matrix als auch deren bessere Verkapselung während der Sprühtrocknung. Es wurde festgestellt, dass sich eine vollständige Abtrennung von Dichlormethan durch die angewendete Destillationsmethode nicht erreichen lässt. Anhand von zwei Modellsystemen — Rizinolsäure- und Ölsäure-beschichteten Magnetitnanopartikeln — und Lösungsmittelgemischen wurde die Stabilität von sterisch stabilisierten Magnetitpartikeln in binären Lösungsmittelgemischen untersucht. Der Fokus bei dieser Untersuchung lag auf der Untersuchung der Stabilität der beschichteten Magnetitnanopartikeln in einer möglichst Dichlormethan- bzw. Isooktan-freien organischen Phase. Als zweites Lösungsmittel (als Lösungsmittelersatz betrachtet) wurden neben Tetrahydrofuran und Isopropanol technisch verbreitete Lösungsmittel wie Isooktan und 1-Butanol eingesetzt. Die Untersuchungsergebnisse zeigen, dass die Anwendung der technischen Rizinolsäure bzw. Ölsäure einen zusätzlichen Einfluss auf die Stabilität der Magnetitpartikeln hat, da diese aus anderen Fettsäuren mit unterschiedlichen chemischen Strukturen bestehen. Die Diskrepanz zwischen der berechneten HANSEN-Distanzen und der Stabilität der Magnetitnanopartikeln mit reinen Fettsäuren lässt vermutet, dass die Zusammensetzung der Lösungsmittelgemische an der fest/flüssig-Grenzfläche anders ist als im freien Volumen. Ein Modell zur Beschreibung der Stabilität der Nanopartikeln, das auf einer Anreicherung des Ausgangslösungsmittels an der Grenzfläche basiert, wurde postuliert. Solange die Diffusion des zweiten Lösungsmittels in die Adsorptionsschicht nicht ausreichend genug ist, um die Löslichkeit der Fettsäureketten entscheidend zu reduzieren und somit einen Abfall der Abstoßungskräfte zwischen der Partikeln hervorzurufen, bleiben alle beschichteten Magnetitnanopartikeln stabil im Lösungsmittelgemisch. Dies ist der Fall für die mit der reinen Rizinolsäure beschichteten Magnetitnanopartikeln in allen verwendeten Lösungsmittelgemischen mit 0,5 Vol. % DCM in der kontinuierlichen Phase. Durch die vorgestellten Herstellungsmethoden wurde gezeigt, dass magnetische Funktionspartikeln sowohl mit festen partikelförmigen Ionenaustauschern als auch mit flüssigen schwachen Polyelektrolyten erfolgreich synthetisiert werden können. Eine nachhaltige Prozessgestaltung durch die Reduzierung der Dichlormethanmenge im Sprühtrocknungsprozess ist auch möglich. Für eine erfolgreiche industrielle Anwendung der Funktionspartikeln müssen aber ihre chemischen sowie mechanischen Eigenschaften deutlich verbessert werden. Dies könnte z.B. durch die Verwendung eines anderen Matrixpolymers oder durch die Entfernung von nicht gebundenen Bestandteilen durch gezielte Waschung der Funktionspartikeln erfolgen. Die Bindungskapazität sowie die Selektivität der oberflächenmodifizierten Funktionspartikeln sollte ebenfalls verbessert werden. Dafür wurde einen Ansatz durch die Quaternisierung der Aminogruppen präsentiert. Schließlich würde die Untersuchung der Stabilität der beschichteten Magnetitnanopartikeln in einphasigen reinen Lösungsmitteln nähere Erkenntnisse über das postulierte Modell der Anreicherung von Dichlormethan in der Adsorptionsschicht erbringen. Dabei könnte die Dichlormethanmenge durch mehrstufige Destillation bzw. Rektifikation beim Lösungsmittelaustausch entfernt werden. Eine vollständige Untersuchung dieses Effekts würde zusätzlich eine Antwort auf zahlreiche Fragestellungen der Kolloidchemie in Bezug auf das Stabilitätsverhalten von Pigmentdispersionen (Lacke) oder von beschichteten Nanopartikeln in Polymerlösungen erbringen.

博士<br>國立成功大學<br>化學工程研究所<br>83<br>Intraparticle diffusion is an important mass transfer step in an adsorption process. Both solid- and pore-diffusion models were widely applied to describe the process of intraparticle diffusion of porous adsorbents. An anion-exchange resin, Ion Exchanger II (Merck), was chosen as the adsorbent in this study. o-Cresol, benzoic acid, p-chlorophenol, and p- nitrophenol were used as adsorbates. Both the fixed-bed and the batch vessel werqe used as the adsorption systems . The equilibrium adsorption data of single adsorbate onto the anion exchange resin revealed that the adsorption of o-cresol, benzoic acid. There were large deviations if the data were corrected by Freundlich isotherms. Equilibrium data showed an approximately linear adsorption isotherm for o-cresol and a favorable one for benzoic acid. Equilibrium data of p- chlorophenol and p-nitrophenol were also nonlinear, but the isotherms were less favorable than benzoic acid. Accordingly, their Langmuir constants were smaller than that of benzoic acid. In modeling the binary adsorption of o-cresol-benzoic acid and p-chlorophenol-p-nitrophenol, an extended Langmuir isotherm showed evident deviations from the equilibrium data. However, the data could be well represented by the modified Langmuir is otherm with interacting factor extracted from experimental com- petitive isotherms. Experiments with the fixed beds were also performed to study the single-component adsorptions of o-cresol and benzoic acid . The experimental breakthrough data was modeled by both the solid- and the pore- diffusion models. When the shape of the adsorption isotherm was approximately linear (say, o-cresol), both models agreed well with the experimental breakthrough data, and they could be effectively applied to predict the breakthrough curve of longer columns. (omit)

碩士<br>國立成功大學<br>化學工程研究所<br>83<br>This study concerns the kinetic study on the removal of urea from aqueous solution with anionic exchanged resin . The kinet- -ics of urea hydrolysis catalyzed by free urease , the immobil- -ized urease , the binding of glutaraldehyde with carriers , as well as the reaction and transport phenomena of urease in the carriers are studied . Our conception is to use glutaraldehyde to be the bridge between carriers and urease , and makes their binding stable . The experiment is operated under 25 to 27 ℃ , and uses phosphate solution 0.1M to be as buffer . In free urea- -se system , we find that the best condition of urea hydrolysis catalyzed by free urease is at pH7.0 of the reaction system , and urea concentration is 0.2M . By the UV - VIS Spectrophotome- -ter can find the amount of glutaraldehyde and urease which bind with carriers . We use A510 and A400 resins to be the carr- iers of urease . The results of our experiment indicate that the amount of urease which A510 resin adsorbed is about four times of A400 resin , and the rate of urea hydrolysis catalyzed by A510 resin is about six times by A400 resin. In accordance with our results of experiment , the condition which immobilized urease has the best activity is : using A510 resin as carrier , the system of immobilized urease being operated at 25 ℃ , pH6.5 , the amount of glutaraldehyde bind- -ing with resin is 0.302 meq- ml^-1 resin , and urea concentr- -ation is 0.2M .

碩士<br>國立成功大學<br>資源工程學系<br>102<br>Separation of Tungsten and Vanadium by Using Anion Exchange Resin Author：Po-Hao Tseng Advisor：Yung-Hui Shen Department of Resource Engineering ＆ National Cheng Kung University SUMMARY Because of advances in industrial technology to bring human more convenient, but accompanied by the pollution and damage to the environment, such as nitrogen oxides NOx. Although the SCR catalyst can efficiently converted the NOx to environmentally sound N2 and H2O.But SCR catalyst has limited lifetime, the spent catalyst recycling will be an important issue of environmental protection for the future. In this study, the primary purpose is separation and recovery of valuable metals tungsten and vanadium in simulant leachate from spent SCR catalyst by anion exchange. Ion exchange method is a low power consumption and simple purification techniques, by using the difference of adsorption capacity between different ions in solution, to achieve separation of the target metal ion. Key words：tungsten; vanadium; separation; ion exchange INTRODUCTION Spent catalyst which is due to the use of a catalyst in the gas is processed, prolonged use at high temperatures, gas or processed exists in the catalyst substances and dust, because: (1) Fouling. (2) Sintering. (3) Collapse. (4)Disappeared of the active ingredient. (5) Poisoning. Resulting in catalytic activity reduced over time, and produce the elimination of waste. Taiwan due to densely populated and metal mineral resources are very limited, must rely on imports from abroad. If you can effectively recycle waste of valuable metals, for waste reduction, environmental protection and reducing the economic costs , there will be a significant help. Due to the increasingly widespread application of SCR technology, the current domestic SCR catalyst amount of waste per year, about 1,000 tons of SCR catalyst waste generated, which contains valuable metals tungsten, vanadium content is not low, if we set up an effective waste separation SCR catalyst of tungsten, vanadium and make recycling process, reducing the cost and environmental issues and sustainable development of resources. Currently, about one-third of the world's tungsten, tungsten metal from waste containing recycled materials. There are ways of recycling waste into valuable metals pyrometallurgical and hydrometallurgical. Hydrometallurgy is the use of water or a suitable solvent to dissolve the metal salts by metal replacement, electrolytic deposition, precipitation, ion exchange… etc., metal ions will to be the metal or compounds. Hydrometallurgy is often necessary to separate and enrich. Ion exchange technology due to its high selectivity, high recovery, low cost, have high-purity compounds to be a popular separation and purification techniques. MATERIALS AND METHODS Tungsten is a transition metalwhich is very hard and the color is gray to white. Its melting point is very high. The worldwide total storage of Tungsten estimated are 700 tons, of which about 30% is wolframite, scheelite is 70%. However, most of these deposits can not be mined by economical manner. According to the current consumption of these deposits is only enough to use about 140 years. Another way to obtain tungsten is recycled. Recovery of tungsten content than tungsten ore high, in fact it is very profitable. The most common oxidation state is +6 valence of tungsten, but it also has an oxidation state between of -1 to +6. The most common oxide of tungsten is trioxide, WO3, which can be dissolved in alkaline water formed to WO42-. Vanadium is a non-magnetic, silver-gray transition metal. Vanadium is difficult to form a independent deposit , it is often associated with other metals in nature, such as: vanadium-titanium magnetite. Therefore, not easy to separate vanadium metal mining and refining. Vanadium oxide stabilized with four valence +5 oxidation state is usually, and there are +2, +3 and +4 valence oxides, but they are easy to transit to +5 valence oxides. Due to the valence of vanadium is very easy to change, it is also often used as a catalyst. +1 valence of vanadium is rarely. Theoretically 0, -1 and -3 valence of vanadium is also possible. Vanadium species present in the aqueous solution of its type in addition to valence, but also by the pH of the solution and Vanadium concentration in solution. This study focused on anion exchange resin to selectively adsorb Tungsten and Vanadium ions, then use elution separate Tungsten and Vanadium, and thus achieve the purpose of the separation and purification. First,understand the important parameters of adsorption by batch adsorption experiments, and then do the resin column test, changing the experimental parameters of different pH, different resins and different types of anionic and different feed rate. In this study, use RELITE JA300LL, AMBERLITE IRA900_Cl, DIAION SA10AOH three resins to do the experiment. The feed of anion exchange column is simulant leachate from spent SCR deNOx catalyst. RESULTS AND DISCUSSION This study includes: 1. Find the optimal resin to separate tungsten and vanadium is strongly basic anion exchange resin IRA900_Cl from three different anion exchange resins . 2. Due to the pH value of solution at 12 or less ,precipitate easily , so the feed of this study is seting to 12.5 pH range of the above , to avoid occuring the precipitation,discourages ion exchanged. 3. The experiment is based on strongly basic anion exchange resin IRA900_Cl,the adsorption capacity in mixed solution of tungsten and vanadium ions , the tungsten is greater than the vanadium. 4. When the pH value of the feed at 12.7or above , the adsorption rate of tungsten is more than 90%, and the pH value at 13.5 or above, the adsorption rate of vanadium will be reduced to 10% or less. This result can be inferred when the pH value at 13.5 or above, it is an opportunity to separate tungsten and vanadium ion. In order to avoid excessive consumption of sodium hydroxide to adjust the pH value with cost considerations, this study is the upper limit of pH 13.7.The other components of the leachate are Si and Al, the adsorption rate of them are very low in this condition. 5. When IRA900_Cl to the Cl -type is the optimum condition, the optimum value of flow rate is when the feed motor at minimum flow rate 0.8ml/min . CONCLUSION When the pH value of the feed is 13.7 , with a strong basic anion exchange resin IRA900_Cl into Cl-type, the feed flow rate is 0.8ml/min. Under the conditions, the vanadium ions adsorbed hardly, whereas most of the tungsten ions adsorbed on the resin. Then use 2M NaCl +1 M NaOH as eluent to desorb ions of tungsten, get the desorption rate of tungsten is 97.86%. To achieve separation of vanadium and tungsten.

碩士<br>國立臺北科技大學<br>化學工程與生物科技系化學工程碩士班（碩士在職專班）<br>105<br>This study was to investigate the use of Purolite A28427 resin as a solid adsorbent to adsorb dichromate ions in aqueous solutions. The adsorption characteristics were investigated by changing the metal concentration, the number of resin, the operating temperature and the pH value of the observation solution. The results show that the equilibrium adsorption capacity of potassium dichromate solution increases with the increase of temperature, but the equilibrium adsorption capacity decreases with the increase of the number of resin. The results of the metal balance are shown in Freundlich, Langmuir, BET isothermal adsorption mode, and the actual results show that the Freundlich isothermal adsorption mode is shown. In addition, the thermodynamic parameters enthalpy (ΔH °), the free energy (ΔG °), and the entropy (Δ S °) are obtained from the metal ion adsorption results. In the K2CrO4 solution system: Δ H°=573~1233 J/mol Δ G°=-4254~-2309 J/mol Δ S°=11.886~15.716 J/ molK

碩士<br>國立臺北科技大學<br>化學工程與生物科技系化學工程碩士班（碩士在職專班）<br>105<br>Using the resin of Purolite A28427 as a solid adsorbents, to adsorb ferrocyanide ion in the solution of potassium hexacyanoferrate(II) trihydrate. By changes in the metal concentration, weight of resin, and operating temperature, discuss the adsorption model. The experiment have shown that the number of moles of ferrocyanide ion which are adsorbed by the resin increased with the initial concentration of potassium hexacyanoferrate(II) trihydrate, and don’t have obviously raised as the weight of resin increased, and the equilibrium adsorption capacities increased with the concentration of the adsorption equilibrium of potassium hexacyanoferrate(II) trihydrate and decreased with the weight of the resin, and the metal removal rate represent decreasing trend as the concentration of the adsorption equilibrium increasing. The experiments have shown that the adsorption behavior is consistent with the Freundlich isothermal adsorption model by comparing the models of Freundlich, Langumir, BET. The thermodynamics parameters of absorption equilibrium of K4Fe(CN)6 system are represented below The concentrations of K4Fe(CN)6 between 0.001 M and 0.0375 M : Δ Ho = -1046.7 ~ -5557.4 J/mol Δ Go = -11086.0 ~ -4420.5 J/mol Δ So = 2.73 ~ 33.69 J/mol.K The concentrations of K4Fe(CN)6 between 0.0375 M and 0.1 M : ΔHo = 2171.6 ~ 17705.9 J/mol ΔGo = -1397.6 ~ -720.3 J/mol ΔSo = 2.67 ~ 65.57 J/mol.K

Natural organic matter (NOM) is present in all surface waters as a result of decaying vegetation, biological activity, and organic soil. Alternative NOM removal processes such as anion exchange resins (AERs) have shown NOM removals typically ranging between 50 to 90%, with up to 99% removal achieved in some cases. The first portion of this study evaluated the performance of two AERs; a conventional Type 1 AER and magnetic ion exchange resin (i.e. MIEX®) for NOM removal from surface water quantified by UV254, dissolved organic carbon (DOC), and specific UV absorbance (SUVA). Samples were also characterized for chloride, sulphate, and chloride-to-sulphate mass ratio (CSMR) to provide additional information on water quality characteristics of AER treated waters. Overall, the results showed that both AERS were effective for removing NOM. However, the MIEX® resin provided greater removal of NOM with shorter contact times compared to the conventional resin investigated. Water treated with MIEX® resin showed significantly higher chloride and lower sulphate concentrations than the conventional AER. Higher CSMR values were found with MIEX® treated water compared to conventional AER system, although both resins showed CSMR much greater than 0.5, which can increase galvanic corrosion effects with lead. Bench-scale jar tests were conducted to investigate the impact of temperature on the efficacy of three NOM removal treatment technologies; enhanced coagulation with alum, MIEX® and a combined MIEX® treatment followed by coagulation with a low dose of alum. Higher settled water turbidity was observed during cold water operating conditions for all three processes. At cold-water operating conditions, DOC removal was reduced with combined MIEX® -Alum treatment, and UV254 removal was impacted for both MIEX® and MIEX® -Alum processes. The combined MIEX®-Alum process was found to provide the lowest THMFP and HAAFP at both temperatures to concentrations lower than current regulatory maximum acceptable concentration (MAC) guidelines in Canada. Surface charge analysis experiments were performed at bench-scale using synthetic water containing humic acid to determine the relationship between NOM and the charge of AER-treated waters. Further bench and pilot-scale studies were performed to investigate the use of surface charge measurements to monitor and optimize NOM removal during treatment with AER systems. Strong correlations were observed between UV254 and respective charge measurements (i.e. ZP, SC) of AER-treated synthetic and raw waters. The results of this research has shown that it is possible to use charge to optimize the MIEX® process for NOM removal. Additionally, it was found that SC measurements could be used as an operational tool for AER processes, where deviations in SC from optimum treatment would indicate the requirement for fresh resin addition or resin regeneration.

abstract: Humans are exposed up to thousands of per- and polyfluoroalkyl substances (PFAS) in the environment, but most of the research and action has been directed towards only two PFAS compounds. These two compounds are part of a subcategory of PFAS called perfluoroalkyl acids (PFAAs). It has been a challenge for the environmental community to mitigate risks caused by PFAAs due to their high persistence and lack of effective measures to remove them from the environment, especially in heavily impacted areas like fire-training sites. The goal of this work was to further answer some questions regarding the removal of PFAAs in the environment by looking at anion exchange resin characteristics and presence of a competing compound, natural organic matter (NOM), in the adsorption of environmentally relevant PFAS compounds including the two often monitored 8-carbon chain PFAAs. Two different resins were tested with two forms of counterions, in both groundwater and NOM impacted groundwater. Resin polymer matrix was the most important property in the adsorption of PFAAs, the two resins used A520E and A860 had similar properties except for their matrices polystyrene (PS) and polyacrylic (PA), respectively. The PS base is most effective at PFAAs adsorption, while the PA is most effective at NOM adsorption. The change in the counterion did not negatively affect the adsorption of PFAAs and is, therefore, a viable alternative for future studies that include regeneration and destruction of PFAAs. The presence of NOM also did not significantly affect the adsorption of PFAAs in the PS resin A520E, although for some PFAAs compounds it did affect adsorption for the PA resin. Ultimately, PS macroporous resins with a strong Type I or Type II base work best in PFAAs removal.<br>Dissertation/Thesis<br>Masters Thesis Engineering 2019

This study focuses on the utilization of Hydrogen Sulphide (H2S) for the synthesis of Dibenzyl Sulphide (DBS) and Benzyl Mercaptan (BM). This involves first the absorption of H2S in mono Ethanolamine and then reaction of this H2S rich mono Ethanolamine with Benzyl Chloride for the synthesis of DBS and BM. The mono Ethanolamine and Benzyl Chloride are two different phases and their reaction is very difficult. So to carry out this reaction a phase transfer catalyst has been used. The Amberlite IR400 has been chosen as the phase transfer catalyst as it is solid and can be reused. The objective of this work is to maximize the conversion of Benzyl Chloride and maximize the selectivity of DBS. In this work the Benzyl Chloride has been used along with Toluene as a solvent. In the system under study, conversion of maximum of 90% was obtained and the desired product was obtained with 46% selectivity. Reaction time, catalyst loading, stirring speed, initial sulphide concentration and Benzyl Chloride concentration are chosen as parameters.

碩士<br>大同大學<br>化學工程研究所<br>91<br>Adsorption and ion exchange processes are widely used to separate heat-sensitive bio-products. In order to design and optimize the separation processes by adsorption or ion exchange, the adsorption isotherm is very crucial. The adsorption equilibrium of beta-glucosidase (EC 3.2.1.21) from the culture broth of Aspergillus niger CCRC 31494 onto Q-Sepharose ion- exchange resin was systematically studied. The effects of temperature (10-30deg.C), concentration of sodium chloride (0-0.5 M) and pH (3-6.2) on the adsorption isotherm of beta-glucosidase were measured experimentally. The results showed that amounts of beta-glucosidase adsorption increased with increasing pH and temperature, but decreased with increasing concentration of sodium chloride. Although the adsorption isotherms under various operating conditions could be adequately fitted by the Langmuir and Freundlich models, a more general adsorption isotherm model was proposed to assess the effects of solution pH, temperature and concentration of sodium chloride.

Nanostructured magnetic materials are important for various applications, and hence their development is critical for the advancement of science and technology. Coupling self-assembly to the generation of magnetic materials in a simple, straight-forward manner has remained a challenge. Here, a series of novel cobalt-functionalized block copolymers (BCPs) with various block ratios were synthesized using ring-opening metathesis polymerization (ROMP). These BCPs self-assembled into different nanostructured morphologies, including cylindrical, lamellar, and inverted cylindrical phases. Upon a simple heat treatment, all these nanostructured materials exhibited room temperature ferromagnetic (RTF) behavior due to the nanoconfinement of the cobalt species within one phase. The effect of dimensionality, or the degree of nanoconfinement, on the macroscopic magnetic properties was studied using superconducting quantum interference device (SQUID) magnetometer. The most highly constrained cylindrical morphology yielded the highest coercivity. The inverted cylindrical morphology, analogous to antidot materials, in which a 3D magnetic matrix is confined between diamagnetic cylinders, showed the second highest coercivity, while the least confined lamellar morphology exhibited the lowest coercivity value. A series of metal-containing block-random copolymers composed of an alkyl-functionalized homo block (C16) and a random block of cobalt complex- (Co) and ferrocene-functionalized (Fe) units was synthesized via ROMP. Taking advantage of the block-random architecture, the influence of dipolar interactions on the magnetic properties of these nanostructured BCPs was studied by varying the molar ratio of the Co units to the Fe units, while maintaining the cylindrical phase-separated morphology. DC magnetic measurements, including magnetization versus field, zero-field-cooled and field cooled, as well as AC susceptibility measurements, showed that the magnetic properties of the nanostructured BCPs could be easily tuned by diluting the cobalt density with Fe units in the cylindrical domains. Decreasing the cobalt density weakened the dipolar interactions of the cobalt nanoparticles, leading to the transition from a room temperature ferromagnetic to a superparamagnetic material. These results confirmed that dipolar interactions of the cobalt nanoparticles within the phase-separated domains were responsible for the RTF properties of the nanostructured BCPs. The effect of domain size on the magnetic properties of these RTF materials was investigated using a series of five cobalt-containing BCPs with various molecular weights and constant block ratios. The BCPs self-assembled into cylindrical morphologies with different domain sizes upon solvent annealing, and then were converted to RTF materials upon a simple heat treatment. The domain sizes of these RTF materials did not show a significant impact on their coercivity values, possibly because the domain size range investigated was not large enough and the cobalt-cobalt dipolar interactions were nearly constant throughout. At the same time, this study confirms that the RTF materials generated from these novel BCPs are robust. (Abstract shortened by UMI.)

碩士<br>國立成功大學<br>環境工程學系碩博士班<br>94<br>The amount of organic matters in some of the source water for public water supply is significant in the offshore islands of Taiwan, such as Kinmen and Penghu. An excess of organic contaminants will cause the formation of disinfection by-products (DBPs) through reacting with chlorine in the water treatment process. In order to inhibit the generation of THMs, some water treatment plants avoid prechlorination to reduce the contact time between chlorine and precursors. However, it may cause the red water problem owing to the low efficiency of iron removal. A possible reason is that the iron is in organic complexed form, which is difficult to remove if the reaction between chlorine and organic complexed iron is insufficient. This research focuses on the removal efficiency of organic complexed iron by magnetic ions exchange resin (MIEX), which is mainly for NOM(natural organic matter) removal. Iron can be analyzed by both flame atomic absorption spectrometry (AA) and spectrophotometer.However, the results show that pretreatment is necessary for the latter and the data obtained by AA is closer to the real value. Therefore, most of the dissolved iron measurement in this study was conducted by AA. Salicylic acid is a simple organic compound, which contains carboxyl and hydroxyl groups; and it may react with transition metal iron to form complex with purple color. XAD-2 resin was need to confirm the ratio of salicylic acid complexed iron in the raw water. Then the effect of pH value, the concentration of salicylic acid, and ferric ion on the amount of complexed iron was stadied.The results show that the ratio of salicylic acid and iron in the complex was 2:1 at pH 4. When pH value was greater than 5, almost all iron turned into ferric hydroxide precipitate. Under pH4, the ratio of complexed iron and total dissolve iron decreased with the pH value, and the results from chemical analysis were near to the theoretical value calculated by Matlab. The removal efficiency of salicylic acid by MIEX might be affected by concentration and pH value. Therefore, the removal efficiency under different pH (2~7) and MIEX dosage (2ml/L~10ml/L) was investigated.The results show the removal efficiency increase with MIEX dosage. It can be up to about 14.58% at 10 ml/L MIEX dosage. The removal efficiency decreased with pH value, was quite low under pH 2.The explanation is:as the pKa1 of salicylic acid is 2.81, so the functional groups would not ionize and be unable to proceed ions exchange with MIEX. Then MIEX was need to remove salicylic acid which complex with iron, and found that MIEX can remove both free and iron-complexed salicylic acids. The removal efficiency of salicylic acid would not be affected by the existence of iron. Finally, the removal of humic acid and himic acid complexed iron by MIEX was also studied. The removal efficiency of humic acid by MIEX was about 50% higher than that of salicylic acid, at dosage 10ml/L. Proobably because the removal of humic acid was by absorption on to MIEX dose to van der Waals force as well as ions exchange reaction. MIEX can remove iron which was complexed with humic acid. The removal efficiency of humic acid was also not be affected by the existence of iron.

碩士<br>國立清華大學<br>化學系<br>104<br>Color is an essential part of the characteristics of food and can affect the products’ success in the food market. Since the visual aspect of a product can be an important factor in a consumer’s decision, artificial color additives are widely used to enhance the appearance of food and beverages to stimulate appetite. Considering the advantages from synthetic dyes including better stability, brightness, lower cost and availability of a range of colors are frequently chosen over natural dyes by food industries. However, in recent years, consumption of synthetic colorants are subject to stringent regulation because of concerns about the potential health risks in public health. As a family compounds in the class of azo dyes, mostly Sudan dyes have been used for coloring chili products by illegal manufacturer due to their strong color giving nature and low cost. Even, Sudan dyes are categorized as Class 3 carcinogens by the International Agency for Research on Cancer (IARC) and, therefore, are illegal as food additives according to both the FDA and the EU. The EU has set detection limits at 0.5-1 mg/kg, and any food material containing more than the limit should be withdrawn from the market. Here, we synthesized a kind of magnetic strong anion exchange adsorbents for the first time, developed sample pretreatment, used UPLC to rapid separate four Sudan Dyes. In this work, firstly magnetic nanoparticles were synthesized using chemical coprecipitation method and followed by coating with polymers of Tetraethoxysilane (TEOS) and N-trimethoxysilylpropyl-N,N,N- trimethylammonium chloride (TMSPTMA) through polymerization process to obtain magnetic strong anion exchange adsorbent (MSAEA). Further the synthesized material was characterized using Z-potential, FT-IR, SEM and SQUID. Sudan dyes contain hydroxyl groups which can be ionized under certain pH range and formed anions, which can be attracted by MSAEA and make it less interference. Consequently, they can be separated by external magnet and eluted using proper solvent and become free state to be detected by UPLC. The result showed that the method had good linearity (r= 0.990–0.997), and the limits of detection (LODs) of four Sudan dyes were from 15 ng/mL. Recoveries obtained by analyzing the five spiked chili oil samples were in the range of 76.4-86.8% and the intra-day and inter-day relative standard deviations (RSDs) were between 3.1-7.6% and 5.2-10.3%, respectively. The results indicated that the novel method could be applied successfully for the determination of Sudan dyes in chili oil samples. MSAEA prepared by this method has high selectivity, easy synthesis, and low solvent consumption, compared to aluminum oxide adsorbent used in national standard method. In addition, our material is consistent with the requirements of green chemistry.

碩士<br>國立勤益科技大學<br>化工與材料工程系<br>106<br>In this study the carbon material obtained by carbonization of waste cation exchange resin. The magnetic carbon material was made by mixing carbon material with an aqueous Fe3+/Fe2+ solution followed by treatment with NaOH. The produced magnetic carbon material adsorbents were used effectively for the removal of methylene blue from aqueous solution. To investigate the effect of on the adsorption efficiency of methylene blue by using adsorbent dose (0.1-0.5 g/100 mL), initial pH (3-10), initial concentration (10-90 mg/L). 　　The results show that the adsorption efficiency is above 95.2% with 0.5 g adsorbent, pH 11, concentration 30 mg/L as the best adsorption conditions. From the surface charge analysis, it can be seen that the magnetic carbon material has a zero charge point of 7.5. In the XRD and FTIR spectra, the appearance of characteristic peaks of magnetite can be found. 　　In the Fenton-Like procedure, we investigated the effect of magnetic carbon materials on the degradation efficiency of methylene blue through initial pH (3, 7, 11) and H2O2 (2, 4, 6 mL). The results show that the addition of 2 mL of hydrogen peroxide had a good catalytic effect in acidic and alkaline environments, the degradation efficiency was 85.9% and 95.6%.

Biofuel is a renewable and sustainable energy source with near-neutral carbon footprint. Algae are an ideal feedstock for biofuel production because they reproduce quickly and have high oil. Algae can be cultivated in non-arable land, and would not impact the food supply. Unfortunately, processing algae into biofuel is more expensive than land crops due to the large volumes of dilute algal suspension that must be harvested and concentrated. In order to improve algae-based biofuel economics, resins were developed that reduce costs associated with water pumping and transport. Hydrophobic resins were developed for binding oil out of an algal suspension so that the residual biomass could be recovered without solvent contamination. Binding behavior displayed lipid species specificity, and binding capacity was improved by ethanol treatment of the biomass. Algae was harvested by binding to anion exchange resin and directly converted into biodiesel. One-step, room temperature in situ transesterification of algae yielded nearly as much biodiesel as two-step, heated transesterification of dried biomass. Elution with transesterification reagent also regenerated the resin for subsequent algal binding. Functionalized resins were developed with high algal binding capacity at neutral pH. Binding was easily reversed, as treatment with buffer with pH higher than pKa of the resin functional group removed the algae and regenerated the resin for subsequent use. The resin bound 10% of its weight in algae and released it as a 100-fold concentrated suspension. The polymers developed can be scaled up for commercial processes and reduce algal harvesting and concentration costs.<br>text