Journal articles: 'Sulfite pulping'

1

Fearon, Olesya, Susanna Kuitunen, and Tapani Vuorinen. "Reaction kinetics of strong nucleophiles with a dimeric non-phenolic lignin model compound with α-carbonyl functionality (adleron) in aqueous alkali solution." Holzforschung 70, no. 9 (September 1, 2016): 811–18. http://dx.doi.org/10.1515/hf-2015-0236.

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Abstract The degradation kinetics of a non-phenolic lignin model compound with α-carbonyl functionality (adlerone) has been studied by varying temperature and concentrations of sodium hydroxide, sodium hydrogen sulfide, and sodium sulfite. The kinetics of adlerone degradation and formation of its reaction products were monitored by UV-Vis spectroscopy and their structures were analyzed by GC/MS. The two step degradation of adlerone was studied in two separate experimental setups. In the first alkali catalyzed step, adlerone is converted to a β-elimination product that reacts further in the second step with hydrogen sulfide or sulfite ion. The Arrhenius kinetic parameters were derived by the KinFit software. The activation energy for the 1st step was 69.1 kJ mol-1, and for the 2nd step with sulfide 42.4 kJ mol-1 and with sulfite ion 35.8 kJ mol-1. The reaction mechanisms presented are in line with those published earlier: β-ether bonds of structures having α-carbonyl functionality do not cleave under soda pulping conditions, whereas in kraft and sulfite pulping the cleavage of β-ether bonds proceeds via nucleophile attack and addition. The combination of hydroxyl and sulfite ions gives the fastest cleavage of β-ether bonds in non-phenolic lignin structures with the α-carbonyl functionality.

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ZHU, J. Y., M. SUBHOSH CHANDRA, ROLAND GLEISNER, WILLIAM GILLES, JOHNWAY GAO, GEVAN MARRS, DWIGHT ANDERSON, and JOHN SESSIONS. "Case studies on sugar production from underutilized woody biomass using sulfite chemistry." TAPPI Journal 14, no. 9 (October 1, 2015): 577–83. http://dx.doi.org/10.32964/tj14.9.577.

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We examined two case studies to demonstrate the advantages of sulfite chemistry for pretreating underutilized woody biomass to produce sugars through enzymatic saccharification. In the first case study, we evaluated knot rejects from a magnesium-based sulfite mill for direct enzymatic sugar production. We found that the sulfite mill rejects are an excellent feedstock for sugar production. In the second study, we presented SPORL (sulfite pretreatment to overcome the recalcitrance of lignocelluloses), a sulfite pretreatment process based on modified sulfite pulping for robust bioconversion of softwood forest residues. Sulfite pulping technology is well developed, with proven commercial scalability, and sulfite pretreatment is a strong contender for commercial adoption.

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FISKARI, JUHA, OLGA DERKACHEVA, and TUOMAS KULOMAA. "QUICK NON-DESTRUCTIVE ANALYSIS OF CONDENSED LIGNIN BY FTIR. PART 2. PULP SAMPLES FROM ACID SULFITE COOKING." Cellulose Chemistry and Technology 55, no. 3-4 (April 20, 2021): 263–70. http://dx.doi.org/10.35812/cellulosechemtechnol.2021.55.26.

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"In our previous work, we demonstrated how lignin condensation and precipitation taking place in kraft pulping can be detected and even quantified by Fourier Transform Infrared (FTIR) spectroscopy. Because lignin reactions in acid sulfite pulping are very different from those occurring during kraft cooking, a new analysis method is proposed to rapidly analyze the condensed lignin in acid sulfite pulp. This kind of analysis is useful for sulfite pulp mills to detect the elevated risk of black cook. This paper presents and discusses the novel method using FTIR spectroscopy to rapidly analyze lignin condensation in softwood pulp samples from acid sulfite processes. Several softwood pulp samples from acid sulfite pulping at varying levels of condensation were included in this research. According to the results, FTIR spectroscopy allows indirect quantification of lignin condensation in a difficult matrix of wood constituents, such as in incompletely delignified acid sulfite pulp."

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Latibari, Ahmad Jahan, Mohammad Ali Hossein, and Reza Hosseinpour. "Application of alkaline sulfite pulping on corn stalks." BioResources 6, no. 1 (November 3, 2010): 48–58. http://dx.doi.org/10.15376/biores.6.1.48-58.

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Alkaline sulfite pulping of corn stalks was investigated to produce supplementary pulp for corrugating board manufacture. Three pulping temperatures (125, 145, and 165°C) and five active alkali charges (10, 12, 14, 16, and 18%) were used. Cooking time at 30 minutes, Na2SO3/ NaOH ratio at 50:50, and liquor to residue ratio of 8:1 were kept constant. The highest total yield (61.9%) was reached applying the treatment combination of 125°C and 10% active alkali, and the lowest total yield (42.5%) was related to 165°C and 16% chemical. The influence of sodium sulfite/sodium hydroxide ratios was studied applying different ratios (30:70, 40:60, 50:50, 60:40, and 70:30) at constant time and temperature of 30 minutes and 145°C respectively and 14 and 16% active alkali. Pulping condition; 16% active alkali, 30 minutes time, 145°C pulping temperature and varying ratios of sodium sulfite/sodium hydroxide were selected for pulp strength evaluation. The results of handsheet evaluation indicated that 16% active alkali, 30 minutes pulping at 145ºC and sodium sulfite/sodium hydroxide ratio of 50:50 is the optimum pulping condition for corn stalks. Tear, tensile, and burst indices and breaking length of this pulp were measured as 10.53 mN.m2g-1, 62.4 N.mg-1, 3.80 kPa.m2g-1, and 6.07 km, respectively.

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Akhtaruzzaman, A. F. M., Samar Kanti Bose, Paritosh Das, and Sujith Kumar Chowdhury. "Neutral sulfite anthraquinone pulping of bagasse." Nordic Pulp & Paper Research Journal 6, no. 1 (January 1, 1991): 8–11. http://dx.doi.org/10.3183/npprj-1991-06-01-p008-011.

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Wang, D. L. K., and R. Patt. "Alkaline Sulfite-Anthraquinone Pulping of Bagasse." Holzforschung 43, no. 4 (January 1989): 261–64. http://dx.doi.org/10.1515/hfsg.1989.43.4.261.

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Högman, Stefan, and Nils Hartler. "Refiner addition of sulfite in mechanical pulping." Nordic Pulp & Paper Research Journal 3, no. 1 (January 1, 1988): 38–43. http://dx.doi.org/10.3183/npprj-1988-03-01-p038-043.

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8

Keskin, A., and G. J. Kubes. "Kinetics of Neutral Sulfite Semichemical and Neutral Sulfite Semichemical-Anthraquinone Pulping." Journal of Wood Chemistry and Technology 14, no. 1 (February 1, 1994): 103–17. http://dx.doi.org/10.1080/02773819408003088.

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9

Wang, Zhe, Jing Wen Xue, Ji Shi Zhang, and Wen Xia Liu. "Ultrafiltration Treatment and Physical Properties of Ammonia Sulfite Pulping Liquor of Wheat Straw." Advanced Materials Research 560-561 (August 2012): 909–13. http://dx.doi.org/10.4028/www.scientific.net/amr.560-561.909.

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Ammonia sulfite pulping liquor of wheat straw was treated by ultrafiltration. Experimental results indicated that the membrane with a cut-off of 10kDa was suitable for concentrating wheat straw liquor and had good anti-fouling property against pulping liquor. Permeability of ash turn higher with the increasing of volume reduction at the operating condition of 200 kPa and 25°C, and retentate was concentrated when volume reduced. Influences of ultrafiltration on physical properties of ammonia sulfite pulping liquor and its retentate after ultrafiltration were studied. Results showed that retentate had better performances as surfactant, concrete additive and dispersant. Surface tension of 1% lignin solution of retentate was 54.7 mN/m, which was lower than that of the untreated original lignosulfonate by 2.2 mN/m. Dispersing effect of retentate on cement was also investigated, it was found that flowability of neat cement paste improved from 70mm to 102mm.

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Do, Vu Thang, Keishi Tanifuji, Guangfan Jin, and Hiroshi Ohi. "Neutral Sulfite Semi–Chemical Pulping of Moso–Bamboo." JAPAN TAPPI JOURNAL 74, no. 4 (2020): 379–87. http://dx.doi.org/10.2524/jtappij.74.379.

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11

LAI, LISA X., and RENATA BURA. "The sulfite mill as a sugar-flexible future biorefinery." August 2012 11, no. 8 (September 1, 2012): 27–35. http://dx.doi.org/10.32964/tj11.8.27.

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The production of single- and mixed-sugar streams and their conversion to bioproducts were studied, using sulfite pulping streams as feedstocks. Sulfite pulp, sludge, and spent sulfite liquor are concurrently generated alongside of bleached pulp, and the pulping process renders pretreatment of solid streams unnecessary. Streams were converted separately; however, due to their low production volume, solid and liquid streams were also combined as a means to increase the quantity of starting feedstock. Spent sulfite liquor, comprising mostly monomeric hexose and pentose sugars, was directly fermented to ethanol and xylitol with Candida guilliermondii. Single-sugar streams were generated through hydrolysis of pulp and sludge in water, followed by fermentation to ethanol with Saccharomyces cerevisiae. Mixed-sugar streams were generated through both separate hydrolysis and fermentation and simultaneous saccharification and fermentation of pulp and sludge in spent sulfite liquor using S. cerevisiae. The best single-sugar source was obtained by hydrolysis of pulp in water, which produced 78.8 g/L of glucose after 96 h. The glucose concentration from hydrolysis of sludge in water was lower (33.5 g/L). Both of these streams were easily converted to ethanol, with yields of 77.8% and 76.2%, respectively. Hydrolyzability of solids was the limiting factor in separate hydrolysis and fermentation conversion of pulp and sludge in water, but hydrolyzability of sludge was not affected when mixed with spent sulfite liquor.

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12

Guo, Zhongpeng, and Lisbeth Olsson. "Characterization and fermentation of side streams from sulfite pulping." Process Biochemistry 49, no. 8 (August 2014): 1231–37. http://dx.doi.org/10.1016/j.procbio.2014.05.002.

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13

Helle, Steve S., Robert A. Petretta, and Sheldon J. B. Duff. "Fortifying spent sulfite pulping liquor with hydrolyzed reject knots." Enzyme and Microbial Technology 41, no. 1-2 (July 2007): 44–50. http://dx.doi.org/10.1016/j.enzmictec.2006.11.022.

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14

Liu, Jing, and Katsuya Nagata. "Target Kappa Number for AS/AQ Pulping of Wheat Straw." Advanced Materials Research 236-238 (May 2011): 1431–36. http://dx.doi.org/10.4028/www.scientific.net/amr.236-238.1431.

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Alkaline sulfite/anthraquinone (AS/AQ) pulping of wheat straw under different conditions was conducted in this study. A transition point of kappa number at approximately 6.5 was observed based on all experimental results. This transition point can be regarded as the phase transfer point in AS/AQ pulping from bulk to residual delignification. Effective delignification without great lost of pulp yield can be achieved before kappa number was below this transition point during AS/AQ pulping of wheat straw. It is found that the ratio of cooking liquid to solid should not be lower than 6, if good mass transfer of chemicals and lignin dissolving is needed. As the ratio of Na2SO3 to NaOH dosage ranged from 0.4 to 2.4, low proportion of Na2SO3 allows effective delignification while no serious degradation of carbohydrate. Moreover, similar to kraft pulping, addition of AQ in the range of 0.05% to 0.25% is useful to remove lignin and protect the carbohydrate during AS/AQ pulping. Finally, although the transition point of kappa number may be changed while different raw material used for same pulping process or different pulping process for same raw materials, it is of interest and important for mill practice.

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15

Lotfy, Vivian F., and Altaf H. Basta. "Electiveness of agro-pulping process in the sustainable production of black liquor-based activated carbons." Royal Society Open Science 6, no. 5 (May 2019): 190173. http://dx.doi.org/10.1098/rsos.190173.

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During the production of paper pulp, the waste water loaded with organic materials from pulping process is discharged. Therefore, water treatment should be performed before disposing of such effluent. The use of such effluent for production of activated carbon will be effective in omitting the wastewater treatment and in obtaining the product required in many industries. In this respect, this paper deals with evaluating the performance of activated carbons (ACs) produced from black liquors (BLs) as by-products from three pulping processes of rice straw (RS) and sugar-cane bagasse (SCB), namely: alkaline, sulfite and neutral sulfite, which are coded SP, SSP and NSP, respectively. Elemental analysis and thermal analysis (TGA and DTGA) are carried out on the BLs, while the surface area ( S BET ), micro-/mesoporous distribution, adsorption capacity of methylene blue (MB) and iodine (I 2 -value), as well as Fourier transform infrared spectra (FT-IR) and scanning electron micrograph (SEM) are studied on synthesizing ACs. The optimal pulping approach for achieving BL-based AC, with the following characteristics: specific surface area ( S BET ) ∼ 921 and 545 m 2 g −1 , MB adsorption capacity 238 and 370 mg g −1 , and I 2 -value 928 and 1255 mg g −1 of BL-based ACs, are from neutral sulfite pulping of SCB (B-NSP) and RS (RS-NSP), respectively. These finding data are ascribed to the carbon content of BL, as well as greatest total volume ( V T 0.786 and 0.701 cm 3 g −1 ) together with decreasing the volume of micropores/total (38 and 48%) of BL-NSP-ACs. It is interesting to note that the AC provided from RS-NSP has greater adsorption capacity for I 2 and MB than the AC produced from RS-pulp fibres.

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Koch, G., B. Rose, R. Patt, and O. Kordsachia. "Topochemical Investigations on Delignification of Picea abies [L.] Karst. during Alkaline Sulfite (ASA) and Bisulfite Pulping by Scanning UV Microspectrophotometry." Holzforschung 57, no. 6 (October 30, 2003): 611–18. http://dx.doi.org/10.1515/hf.2003.092.

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Summary Delignification of spruce (Picea abies [L.] Karst.) during ASA (modified alkaline sulfite/anthraquinone pulping with alkali splitting) and magnesium bisulfite pulping was studied on a cellular level using scanning UV microspectrophotometry. This improved cellular analytical technique enables direct imaging of the topochemistry of lignin removal within the cell wall at different stages of cooking. The cooks were performed in a laboratory digester with forced liquor circulation. At 30 min intervals samples were taken for chemical and UV microscopic analyses. UV microscopy reveals that delignification during ASA pulping starts in the region of the pit canals and proceeds evenly across the entire S2 layer. As a specific feature of bisulfite pulping, a partial delignification of the radial compound middle lamella can be detected after 60 min of cooking. After 120 min, in both processes, the delignified cell walls show low UV absorbance values of both S2 and compound middle lamella. At this stage, approximately 90% of the initial lignin content is removed. At the end of both pulping processes, only parts of the cell corners can be distinguished by the new UV scanning technique.

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Basta, Altaf H., Vivian F. Lotfy, and Philippe Trens. "Role of pulping process as synergistic treatment on performance of agro-based activated carbons." Royal Society Open Science 6, no. 7 (July 2019): 190579. http://dx.doi.org/10.1098/rsos.190579.

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To recommend the beneficial effect of the pulping process on enhancing agro-wastes as precursors for the production of high-performance activated carbons (ACs), different pulping methods (alkali, sulfite and neutral sulfite) were applied on two available Egyptian agriculture by-products (rice straw and sugar cane bagasse), using the one-step pyrolysis method and H 3 PO 4 activating agent. The adsorption performance of the different prepared ACs was evaluated in terms of Iodine Numbers and their sorption properties for removing the methylene blue (MB) from aqueous solutions. The corresponding sorption processes were also analysed using Lagergren first order, pseudo-second order and intraparticle diffusion models. Data revealed that the applied pulping conditions were effective for removing the non-cellulosic constituents of agro-residues. This was demonstrated by the hydrogen/carbon and oxygen/carbon ratios, thermal stability and IR-measurements of the final pulps. These data were effective on the particular sorption properties of RS and SCB-based ACs. Interestingly, the pulping process is a profound modification of the SCB-based fibres, on which it induced a clear increase of the specific surface areas of the corresponding ACs even though they had an impact on the sorption of MB and iodine. These values are superior to the reported data on agro-based ACs with H 3 PO 4 activators. Pulping processes therefore play a dual role in the sorption properties of ACs. The first important role is the impact on the specific surface areas and the second impact is a profound modification of the surface chemistry of the ACs. Therefore, SCB-based ACs can be seen as an economical breakthrough product, and an alternative to the high-cost commercial ACs for the purification of industrial wastewaters.

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Rueda, Cristina, Pedro A. Calvo, Gabriel Moncalián, Gema Ruiz, and Alberto Coz. "Biorefinery options to valorize the spent liquor from sulfite pulping." Journal of Chemical Technology & Biotechnology 90, no. 12 (September 26, 2014): 2218–26. http://dx.doi.org/10.1002/jctb.4536.

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Vidaurre, Graziela Baptista, Miguel Pereira, Walter Torezani Neto Boschetti, Rudolf Patt, Jorge Luiz Colodette, Benedito Rocha Vital, and Maria Naruna Felix de Almeida. "NSSC pulping of fast growing trees." Nordic Pulp & Paper Research Journal 33, no. 3 (September 25, 2018): 404–13. http://dx.doi.org/10.1515/npprj-2018-3044.

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Abstract Neutral sulphite semichemical pulping (NSSC) of Schizolobium amazonicum (Paricá), a fast-growing Amazonian tree, was compared with that of Eucalyptus grandis (eucalypt), one of the most important wood sources for the Brazilian pulp industry, and with mixtures of both woods in different proportions (mix). Wood chips prepared from 7-year old trees were steamed, cooked using the NSSC process and defibered in a 12” disc refiner in three stages. The paricá wood produced pulp of lower yield (75 %) than eucalypt (77 %) at 16 % sulfite/150 min/170 °C. The paricá and eucalypt pulps were bleached to about 68 and 74 % ISO brightness, respectively, by the QPFAS sequence. Paricá consumed more energy for refining in comparison with the eucalypt wood. The wood mix produced lower yield and brightness than the single species processed separately.

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20

Kroiss, H., K. Svardal, and H. Fleckseder. "Anaerobic Treatment of Sulfite Pulp Mill Effluents." Water Science and Technology 17, no. 1 (January 1, 1985): 145–56. http://dx.doi.org/10.2166/wst.1985.0012.

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Sulfite pulping will still play an important role in Austria in the foreseeable future. Therefore, efficient and economic means of waste-water treatment have to be searched for. The experience gained with operating laboratory scale and semi-technical scale experiments for anaerobic treatment of condensates and the extraction stage effluent from two mills is presented. As we foresee, in full scale conditions a series of problems arise (neutralization, solids retention, SO2 toxicity, start-up of process) The advantage of the anaerobic process in terms of energy alone cannot, as we had to realize, be the single basis of the investment decision.

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Vincent, Pauline, Frédérique Ham-Pichavant, Christelle Michaud, Gérard Mignani, Sergio Mastroianni, Henri Cramail, and Stéphane Grelier. "Extraction and Characterization of Hemicelluloses from a Softwood Acid Sulfite Pulp." Polymers 13, no. 13 (June 22, 2021): 2044. http://dx.doi.org/10.3390/polym13132044.

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Hemicelluloses were extracted from a softwood acid sulfite pulp in a three-step procedure. Further delignification step resulted in a holocellulose pulp containing only 1.7 wt.% of the lignin left. Cold caustic extraction (CCE) with 18 wt.% NaOH at 60 °C for 1 h was performed to solubilize hemicelluloses of the holocellulose. An unbleached cellulose pulp was then obtained 97% pure, which indicates that 89% of the hemicelluloses were removed. After purification, extraction yields between 1.1 wt.% and 9.5 wt.% were obtained from the delignified pulp and the hemicelluloses’ chemical compositions and structures were investigated by 1H, 13C nuclear magnetic resonance spectroscopy (NMR) and two-dimensional NMR by correlation spectroscopy (2D-COSY) and proton-detected heteronuclear single-quantum correlation (2D-HSQC), high-performance anion-exchange chromatography coupled with a pulsed amperometry detector (HPAEC-PAD), size-exclusion chromatography coupled with a refractive index detector (SEC-RI) and thermogravimetric analyses (TGA). Hemicelluloses were obtained with a purity of 96%, with short cellulosic chains as the only residue. Sulfite pulping modified the hemicelluloses’ structure, and it was found that two types of hemicelluloses were isolated, glucomannans, predominant at 67%, and methylglucuronoxylans. Finally, alkali-soluble hemicelluloses displayed relatively narrow size distributions and low molar masses, Mw varying between 18,900 and 30,000 g/mol after acid sulfite pulping.

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Paananen, Markus, Stella Rovio, Tiina Liitiä, and Herbert Sixta. "Effect of hydroxide and sulfite ion concentration in alkaline sulfite anthraquinone (ASA) pulping – a comparative study." Holzforschung 69, no. 6 (August 1, 2015): 661–66. http://dx.doi.org/10.1515/hf-2014-0303.

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Abstract Pulp and black liquor produced by alkaline sulfite anthraquinone (ASA) process were comprehensively characterized to evaluate the effects of ion concentration on the delignification and polysaccharide preservation. Scots pine wood meal was pulped at 160°C with a sulfite-to-hydroxide ion ratio of 0.75 and liquor-to-wood ratio of 200:1. Two concentration levels were studied in presence and absence of anthraquinone (AQ). Contrary to the expectations, already the lower concentration level (L-ASA) revealed rapid delignification in presence of AQ, while only moderate acceleration was obtained at the high concentration level (H-ASA). However, H-ASA liquor resulted in a slightly higher pulp yield of 1–2% (based on wood) but only in case of pulps with kappa numbers (KN) above 60. With progressing delignification, the yield advantage was gradually lost. The higher pulp yield at H-ASA conditions was mainly due to improved galactoglucomannan retention, which was around 2% on KN60 pulp and around 0.5% after prolonged delignification. The xylan content, on the other hand, was found to be 1% (based on wood) lower under H-ASA conditions compared to L-ASA conditions, which may be attributed to an increased solubility of short-chain polysaccharides at high alkali concentration.

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JAHAN, M. SARWAR, SUMON GOSH, M. MOSTAFIZUR RAHMAN, and YONGHAO NI. "Nonwood pulping: use of jute cuttings and caddis in Bangladesh." September 2013 12, no. 9 (October 1, 2013): 41–46. http://dx.doi.org/10.32964/tj12.9.41.

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Utilization of jute cutting and caddis is of social and economic importance in Bangladesh. In this study, soda-anthraquinone, alkaline sulfite-anthraquinone, and neutral sulfite-anthraquinone processes were evaluated for jute-cutting and caddis pulping. The NS-AQ process showed favorable pulp yield and kappa number for both of these raw materials: 66.1% for jute cuttings and 59.9% for caddis at kappa no. 11. The physical properties of NS-AQ pulps were also better than those of soda-AQ and AS-AQ pulps. At 0SR 44, the tensile index of NS-AQ pulp was about 100 N.m/g for jute cutting and 70 N.m/g for caddis, and the tear index was similar. All pulps were bleached by D0EpD1 bleaching sequences. The NS-AQ pulp showed excellent bleachability. Its brightness reached 89.0% for jute cuttings and 85.0% for caddis using total chlorine dioxide of about 15 kg/ton. After bleaching, the strength properties of NS-AQ pulp were slightly better compared to soda-AQ and AS-AQ pulps.

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Kou, Xiao Meng, Rui Feng Yang, Jie Lu, and Yan Jun Liu. "Alkali Precipitation Properties of Magnesium Lignosulfonate Isolated from Acid Sulfite Pulping Waste Liquor." Applied Mechanics and Materials 522-524 (February 2014): 416–19. http://dx.doi.org/10.4028/www.scientific.net/amm.522-524.416.

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To establish a simple method to separate and purify the magnesium lignosulfonate from the red liquor, the properties of the alkali precipitation of magnesium lignosulfonate in the red liquor were investigated. The results show that the magnesium lignosulfonate could be precipitated by alkali from red liquor. The maximum amount of precipitation occurs when pH value was 13. The precipitation of the red liquor of acid magnesium sulfite is caused by magnesium. It was different from sodium lignosulfonate of the red liquor of acid sodium sulfite. The repeated alkaline precipitation after acid soluble method could be isolated and purified lignosulfonate magnesium effectively at some extent.

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Mendonça, Régis, André Ferraz, Othar Kordsachia, and Rudolf Patt. "Alkaline sulfite/anthraquinone pulping of pine wood chips biotreated withCeriporiopsis subvermispora." Journal of Chemical Technology & Biotechnology 79, no. 6 (May 6, 2004): 584–89. http://dx.doi.org/10.1002/jctb.1024.

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Tarasov, Dmitry, Mathew Leitch, and Pedram Fatehi. "Thermal properties of lignocellulosic precipitates from neutral sulfite semichemical pulping process." Fuel Processing Technology 158 (April 2017): 146–53. http://dx.doi.org/10.1016/j.fuproc.2016.12.017.

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Iglesias, Maria C., Diego Gomez-Maldonado, Brian K. Via, Zhihua Jiang, and Maria S. Peresin. "Pulping Processes and Their Effects on Cellulose Fibers and Nanofibrillated Cellulose Properties: A Review." Forest Products Journal 70, no. 1 (January 1, 2020): 10–21. http://dx.doi.org/10.13073/fpj-d-19-00038.

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Abstract Although pulping processes from wood are well-cemented technology, the emergence of bio-based nanotechnology, as well as the increase in concern about the environmental impact that these processes can have, calls for a reevaluation of the impacts that the traditional pulping methods have on the surfaces of the fibers and how variances will then affect the generation and properties of the nanocellulose materials, that will then impact the different applications that can be derived from them. Since literature tends to focus on one method and then characterize it, the aim of this review is to discuss the properties that have been reported of different fibers and nanofibers depending on the wood source, the chemical pulping method selected (kraft or sulfite methods), and the bleaching or lack of it and then compare the effects that these can have in properties such as crystallinity, chemical composition, surface charge, and functional groups present on the surface.

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Mašura, V. "A mathematical model for neutral sulfite pulping of various broadleaved wood species." Wood Science and Technology 32, no. 1 (March 1998): 1–13. http://dx.doi.org/10.1007/bf00702555.

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ura, V. Ma w. "A mathematical model for neutral sulfite pulping of various broadleaved wood species." Wood Science and Technology 32, no. 1 (March 24, 1998): 1–13. http://dx.doi.org/10.1007/s002260050054.

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Lehnen, R., B. Saake, and H. H. Nimz. "Impact of Pulping Conditions on FORMACELL Aspen Lignin: Investigation of Methoxyl and Ester Groups, Carbohydrates, Molar Mass and Glass Transition Temperatures." Holzforschung 56, no. 5 (August 26, 2002): 498–506. http://dx.doi.org/10.1515/hf.2002.077.

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Summary The influence of reaction time, reaction temperature and acid concentration on the yield and characteristics of FORMACELL aspen lignins were investigated. 18 samples were quantitatively isolated from the black liquor by precipitation. The samples were analysed regarding their contents of carbohydrates, methoxyl and ester groups. All samples had low carbohydrate contents and the amount of methoxyl and ester groups was continuously reduced under more severe pulping conditions. Molar mass distributions and glass transition temperatures were determined. Molar masses of lignins were continuously reduced during pulping resulting in low weight average molar masses from 2.500–3.200 g/mol. Glass transition temperatures varied from 123.6 to 154.5°C, depending on the reaction conditions. Comparison of the thermograms with those of the lignins from the Kraft or Sulfite process confirmed that in the FORMACELL process a very uniform lignin with few impurities is obtained.

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Hedjazi, Sahab, Othar Kordsachia, Rudolf Patt, Ahmad Jahan Latibari, and Ulrike Tschirner. "Bagasse alkaline sulfite-anthraquinone (AS/AQ) pulping and totally chlorine free (TCF) bleaching." Holzforschung 62, no. 2 (March 1, 2008): 142–48. http://dx.doi.org/10.1515/hf.2008.044.

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Abstract Alkaline sulfite/anthraquinone (AS/AQ) pulping and totally chlorine free (TCF) bleaching of bagasse was investigated. Depithed and wet cleaned bagasse was collected from the Pars Paper Company in southern Iran, dried and then pulped. The active alkali charge was chosen between 16 and 20% on oven-dry bagasse and the alkali ratio, Na2SO3/NaOH, was varied from 30/70 to 70/30. The AQ dose was kept constant. While keeping a constant cooking time at maximum temperature for 60 min, the maximum temperature was varied between 155 and 165°C. For bleaching, a pulp with a kappa number of 8.5 was produced under the following conditions: 18% active alkali, alkali ratio 30/70, 60 min cooking at 155°C. TCF bleaching was performed with oxygen and hydrogen peroxide. Oxygen delignification (O) with an alkali charge of 2% NaOH resulted in 50% degree of delignification. A brightness of 80% ISO was achieved with a chelating treatment (Q) and a subsequent oxygen reinforced peroxide bleaching stage (OP) under drastic conditions (4% H2O2, 2.75% NaOH, 90 min at 98°C). With an additional peroxide bleaching stage charging 2% H2O2, the brightness could be further improved to 83.5% ISO. Bleaching led to only small losses in tensile and burst strength at unchanged tear strength. Short beating in a Jokro mill was sufficient to attain good pulp strength. The results indicate that AS/AQ pulping and TCF bleaching can be successfully applied to bagasse to produce pulp for writing and printing paper.

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Sakai, Kokki, Sung-Phil Mun, and Hiroyuki Imamura. "Monomeric Products Formed from the Lignin of Sugi Wood During Alcohol Sulfite Pulping." Journal of Wood Chemistry and Technology 6, no. 4 (January 1986): 523–34. http://dx.doi.org/10.1080/02773818608085243.

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33

Magina, Sandra, Ana Barros-Timmons, and Dmitry V. Evtuguin. "Laccase-catalyzed oxidative modification of lignosulfonates from acidic sulfite pulping of eucalyptus wood." Holzforschung 74, no. 6 (February 11, 2020): 589–96. http://dx.doi.org/10.1515/hf-2019-0272.

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AbstractLignosulfonates (LS) from acidic magnesium-based sulfite cooking of Eucalyptus globulus wood were modified via laccase-catalyzed oxidative treatment with the aim to improve their performance as plasticizing additives in concrete formulations. The target parameters were the increment of molecular weight (Mw) and the amount of oxidized groups. The laccase-assisted oxidation under optimized conditions (40°C, pH 4.5, enzyme loads of 83–500 U g−1 for 90 min) allowed Mw increment up to 11-fold and almost doubled the amount of carbonyl and carboxyl groups without using any mediators. Modified LS maintained their solubility in water and possessed a zeta- potential close to that of initial LS. The characterization of modified LS has been carried out by ultraviolet-visible (UV-Vis), Fourier transform infrared-attenuated total reflectance (FTIR-ATR) and quantitative 13C nuclear magnetic resonance (NMR) spectroscopy, and the sulfonic and phenolic groups were assessed by conductometric titration. It was concluded that LS polymerization occurred mostly via the formation of new aryl ether bonds (two thirds of the modification) and biphenyl bonds (the remaining third). However, part of the newly formed bonds of unknown origin are temperature labile and cleaved during the concentration of LS at pH 4 and 80°C under vacuum, which led to the reduction of the Mw of the modified lignin to almost one third.

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Wang, D. L. K., F. Ramirez, and R. Patt. "Alkaline Sulfite-Anthraquinone Pulping of Bagasse with and without the Addition of Ethanol." Holzforschung 41, no. 6 (January 1987): 383–88. http://dx.doi.org/10.1515/hfsg.1987.41.6.383.

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35

Fatehi, Pedram, Weijiue Gao, Yonghui Sun, and Mehdi Dashtban. "Acidification of prehydrolysis liquor and spent liquor of neutral sulfite semichemical pulping process." Bioresource Technology 218 (October 2016): 518–25. http://dx.doi.org/10.1016/j.biortech.2016.06.138.

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36

Kantardjieff, A., and J. P. Jones. "Practical experiences with aerobic biofilters in TMP (thermomechanical pulping), sulfite and fine paper mills in Canada." Water Science and Technology 35, no. 2-3 (February 1, 1997): 227–34. http://dx.doi.org/10.2166/wst.1997.0525.

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An industrial aerobic biofilter technology has been piloted extensively in Canada on several types of pulp and paper mill effluents, resulting in one full scale operational facility at one Canadian fine paper mill. In addition two industrial scale pilot plant tests were performed with the same technology, one in an integrated sulfite pulp and paper mill and one in a TMP mill. In the case of the fine paper mill, the full scale plant has two cells (8 m × 8 m × 6 m height of the media) and treats an unclarified but screened effluent with a loading of 3500 kg BOD/d. The system produces low quantities of biosludge (0.28 kg TSS/kg BOD removed), has a rapid rate of recovery after shock loadings and is very energy efficient (150 kW installed power for aeration). Pilot plant treatability studies were performed at one integrated Canadian sulfite mill using a combination of a biofilter-aerated lagoon system. The biofilter treated the most concentrated stream (sulfite pulp mill effluent) and this stream was then combined with the remaining wastewaters of the mill and polished in an aerated stabilization basin (ASB). The high quality ASB effluent (50 mg BOD/L/30 mg TSS/L) was non toxic to rainbow trout, Daphnia magna and photoluminescent bacteria. Integrated TMP mill effluents were treated in a 5 m3 aerobic biofilter filled with two types of media (10 to 20 mm and 20 to 30 mm). Under average loading conditions of 3.5 kg BOD/d.m3 media, the system produced effluents meeting regulation limits for BOD, TSS as well as for toxicity.

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37

Ringena, Okko, Bodo Saake, and Ralph Lehnen. "Characterization of electrolyzed magnesium spent-sulfite liquor." Holzforschung 59, no. 6 (November 1, 2005): 604–11. http://dx.doi.org/10.1515/hf.2005.098.

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Abstract Spent sulfite liquor derived from magnesium bisulfite pulping of beech was electrolyzed in a pilot-plantelectrolysis cell. During the electrochemical treatment (125 mA cm−2; 60°C; 180 min), desalination of the anolyte took place and the magnesium concentration was reduced to approximately 60%. In addition, the pH decreased from 5 to 1. Three differently treated liquors (SSL pH 5; SSLe pH 2.5; SSLe pH 1) were chosen for further analysis. The average molar mass of the fractions was determined by size exclusion chromatography. Extended electrolysis time increased the molar mass of the lignosulfonates (M w: SSL pH 5, 5700 g mol−1; SSLe pH 2.5, 6500 g mol−1; SSLe pH 1, 7400 g mol−1). The content of phenolic hydroxyl and sulfonic acid groups did not undergo significant changes. Nevertheless, lignosulfonates obtained after electrolysis showed higher charge densities than the unmodified product (SSL pH 5, 1590 μeq g−1; SSLe pH 2.5, 1760 μeq g−1; SSLe pH 1, 1920 μeq g−1). Separation of the liquors into five fractions was performed using four ultrafiltration membranes (100, 50, 10 and 1 kDa). This allowed detailed structural analysis of high- and low-molar-mass lignosulfonate fractions in terms of the modifications induced by electrolysis.

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Rehbein, Mathias, Miguel Pereira, Gerald Koch, and Othar Kordsachia. "Topochemical investigation into the delignification of Eucalyptus globulus chips during semi-chemical sulfite pulping." Wood Science and Technology 44, no. 3 (July 14, 2010): 435–49. http://dx.doi.org/10.1007/s00226-010-0363-1.

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39

Strunk, Peter, Åsa Lindgren, Roland Agnemo, and Bertil Eliasson. "Properties of cellulose pulps and their influence on the production of a cellulose ether." Nordic Pulp & Paper Research Journal 27, no. 1 (January 1, 2012): 24–34. http://dx.doi.org/10.3183/npprj-2012-27-01-p024-034.

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Abstract Several grades of cellulose pulps were investigated for their influence on the product quality of a cellulose ether, ethyl-hydroxy-ethyl cellulose (EHEC). The selection of the pulps was based on pulping process, original wood type and intrinsic viscosity. In total, five sulfite pulps and four sulfate pulps were chosen, of which all but one sulfate pulp were of dissolving grade. The physical and chemical properties of the pulps were analyzed as well as important qualitative parameters of the final product EHEC. The influence of pulp properties on EHEC quality was investigated by multivariate data analyses. Principal component analysis showed that due to the influence of all variables, the pulps aligned in groups in accordance to the selection criteria pulping process and wood type. Partial least square regression revealed that high gel formation in EHEC is explained by the pulp properties high intrinsic viscosity and high Mw in combination with high caustic absorption rate and high total caustic absorption. The amount of hemicelluloses, in particular xylose, also contributed to gel formation. High cloud point for an EHEC solution was explained by a high MSEO and low DSEt of the EHEC molecules, where in turn a high MSEO could be predicted by a high pore area, high PD and a low caustic absorption rate. A low DSEt could on the other hand be predicted by a low hemicellulose content and hence a high R18. In a separate model, the same pulp properties explaining MSEO and DSEt also predicted cloud point directly. Fock reactivity and viscose dope filterability, both test methods originating from the viscose manufacturing, were shown to predict cloud point but have low predictability on other EHEC quality parameters. The models achieved can thus be utilized to predict final EHEC product qualities for new pulps within the design set of the chosen pulps.

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Tormund, Disa, and Ants Teder. "Elimination of malodorous organic sulfur compounds from the kraft pulping process with polythionate and sulfite." Nordic Pulp & Paper Research Journal 2, no. 3 (August 1, 1987): 97–100. http://dx.doi.org/10.3183/npprj-1987-02-03-p097-100.

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41

Shen, Wenhao, and Xiaoquan Chen. "Measuring and Controlling Model of Pulp Kappa Number with Spectroscopy during Batch Sulfite Pulping Process." Industrial & Engineering Chemistry Research 48, no. 19 (October 7, 2009): 8980–84. http://dx.doi.org/10.1021/ie900327a.

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42

Gümüşkaya, Esat, Emir Erişir, Hüseyin Kirci, and Nuray Misir. "The Effect of Sodium Borohydride on Alkaline Sulfite–Anthraquinone Pulping of Pine (Pinus pinea) Wood." Industrial & Engineering Chemistry Research 50, no. 13 (July 6, 2011): 8340–43. http://dx.doi.org/10.1021/ie200633z.

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43

Geng, Xinglian, Ryuichiro Kondo, Kokki Sakai, and Zhongzheng Lee. "Improvement of dispersing property of sodium sulfite-formal-dehydeanthraquinone pulping effluent by treatment withCoriolus versicolor." Journal of Wood Science 45, no. 2 (April 1999): 143–48. http://dx.doi.org/10.1007/bf01192331.

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44

Pinel, Dominic, Frédéric D'Aoust, Stephen B. del Cardayre, Paramjit K. Bajwa, Hung Lee, and Vincent J. J. Martin. "Saccharomyces cerevisiae Genome Shuffling through Recursive Population Mating Leads to Improved Tolerance to Spent Sulfite Liquor." Applied and Environmental Microbiology 77, no. 14 (May 27, 2011): 4736–43. http://dx.doi.org/10.1128/aem.02769-10.

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ABSTRACTSpent sulfite liquor (SSL) is a waste effluent from sulfite pulping that contains monomeric sugars which can be fermented to ethanol. However, fermentative yeasts used for the fermentation of the sugars in SSL are adversely affected by the inhibitory substances in this complex feedstock. To overcome this limitation, evolutionary engineering ofSaccharomyces cerevisiaewas carried out using genome-shuffling technology based on large-scale population cross mating. Populations of UV-light-induced yeast mutants more tolerant than the wild type to hardwood spent sulfite liquor (HWSSL) were first isolated and then recursively mated and enriched for more-tolerant populations. After five rounds of genome shuffling, three strains were isolated that were able to grow on undiluted HWSSL and to support efficient ethanol production from the sugars therein for prolonged fermentation of HWSSL. Analyses showed that greater HWSSL tolerance is associated with improved viability in the presence of salt, sorbitol, peroxide, and acetic acid. Our results showed that evolutionary engineering through genome shuffling will yield robust yeasts capable of fermenting the sugars present in HWSSL, which is a complex substrate containing multiple sources of inhibitors. These strains may not be obtainable through classical evolutionary engineering and can serve as a model for further understanding of the mechanism behind simultaneous tolerance to multiple inhibitors.

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45

Al-Rudainy, Basel, Mats Galbe, Frank Lipnizki, and Ola Wallberg. "Galactoglucomannan Recovery with Hydrophilic and Hydrophobic Membranes: Process Performance and Cost Estimations." Membranes 9, no. 8 (August 10, 2019): 99. http://dx.doi.org/10.3390/membranes9080099.

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In this study, we compared the GR51PP (hydrophobic/polysulfone) membrane with a series of hydrophilic (regenerated cellulose) membranes with the aim of increasing the retention of products and decreasing membrane fouling. The raw material used was a sodium-based spent sulfite liquor from the sulfite pulping process of spruce and pine. The results show that the hydrophilic membranes were superior to the hydrophobic membranes in terms of higher fluxes (up to twice the magnitude), higher product retentions and less fouling (up to five times lower fouling). The fouling was probably caused by pore blocking as observed in earlier studies. However, the hydrophilic membranes had a lower affinity for lignin, which was indicated by the lower retention and fouling. This also resulted in a separation degree, which was higher compared with the hydrophobic membrane, thus yielding a higher galactoglucomannan (GGM) purity. 2D HSQC NMR results show that no major structural differences were present in the hydrophilic and hydrophobic retentates. A techno-economical evaluation resulted in the RC70PP being chosen as the most cost-efficient membrane in terms of flux and product recovery.

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46

Allahdady, Maryam, Sahab Hedjazi, Mehdi Jonoobi, Ali Abdulkhani, and Loya Jamalirad. "The influence of bio-fibers from different pulping processes on the pulp-polylactic acid composites (PPCs) properties from sugarcane bagasse." Nordic Pulp & Paper Research Journal 34, no. 3 (September 25, 2019): 239–49. http://dx.doi.org/10.1515/npprj-2019-0048.

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Abstract Pulp-polylactic acid composites (PPCs) with monoethanolamine, alkaline sulfite-anthraquinone, unbleached and bleached soda bagasse pulps and polylactic acid (PLA) were successfully fabricated using twin-screw extrusion. The results were compared with bagasse flour-PLA composites (WPCs) as reference. The results indicated that the mechanical strengths of produced composites with pulp fibers were increased compared to the neat PLA and bagasse flour-PLA composites. Monoethanolamine and alkaline sulfite-anthraquinone fibers due to their surface chemical structure had a superior compatibility with PLA compared with other used bio-fibers which has been confirmed by SEM micrographs too. FTIR was used to investigate the effect of different chemical treatments on the bio-fibers. The results of XRD analysis showed that the crystallinity of PPCs was substantially improved by incorporation with pulp fibers compared to WPCs composites. The water absorption of the PPCs is different due to using the diverse bio-fibers. According to DMA analysis, the tan delta was substantially decreased when PLA was reinforced by different bio-fibers. The biodegradation of green composites were characterized and the results showed that the biodegradability of the PLA was increased due to addition of bagasse pulp biofibers.

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47

Kienberger, Marlene, Silvia Maitz, Thomas Pichler, and Paul Demmelmayer. "Systematic Review on Isolation Processes for Technical Lignin." Processes 9, no. 5 (May 3, 2021): 804. http://dx.doi.org/10.3390/pr9050804.

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Technologies for the isolation of lignin from pulping process streams are reviewed in this article. Based on published data, the WestVaco process, the LignoBoost process, the LigoForce SystemTM and the SLRP process are reviewed and discussed for the isolation of lignin from Kraft black liquor. The three new processes that have now joined the WestVaco process are compared from the perspective of product quality. Further, isolation processes of lignosulfonates from spent sulfite liquor are reviewed. The limitation for this review is that data are only available from lab scale and pilot scale experiments and not from industrial processes. Key output of this paper is a technology summary of the state of the art processes for technical lignins, showing the pros and cons of each process.

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48

Konn, Jonas, Andrey Pranovich, and Bjarne Holmbom. "Dissolution of fibre material in alkaline pre-treatment and refining of spruce CTMP." Holzforschung 60, no. 1 (January 1, 2006): 32–39. http://dx.doi.org/10.1515/hf.2006.007.

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Abstract The chemistry of chemithermomechanical pulping (CTMP) was assessed by chemical pre-treatment of spruce chips, followed by laboratory-scale refining. Pre-treatments with alkali, sulfite, alkaline sulfite and alkaline peroxide liquors were carried out at 40°C, 60°C and 80°C. The sodium hydroxide dosages were 1% and 2% and the sodium sulfite and hydrogen peroxide dosages were 2%, 4% and 6% on a dry wood basis. Process water samples were taken before and after refining. Alkali consumption in the pre-treatments and the amount and composition of released wood components were determined. A major part of the alkali was consumed in the alkaline and alkaline sulfite pre-treatments. In the alkaline peroxide pre-treatments, however, alkali consumption was considerably lower. Acetic acid was the main wood component released to the process waters in alkaline pre-treatments. Pectins, determined as galacturonic acid and rhamnose by acid methanolysis, were also released to some extent, as well as easily soluble polysaccharides. After fibre separation in refining, more hemicelluloses and pectins were released. There was a significant difference between the degree of demethylation for pectins and the degree of deacetylation for galactoglucomannans after the pre-treatments. The diffusion of chemicals into the secondary wall layers seemed to be slower than the liquor penetration into the porous middle lamella through the pit pores. Up to 10% of the pectins were dissolved in the process waters as a result of depolymerisation and extensive demethylation. The residual amount of pectins in the fibres, however, was determined to be as low as 65–70% of the initial pectin content.

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Hedjazi, Sahab, Othar Kordsachia, Rudolf Patt, Ahmad Jahan Latibari, and Ulrike Tschirner. "Alkaline sulfite–anthraquinone (AS/AQ) pulping of wheat straw and totally chlorine free (TCF) bleaching of pulps." Industrial Crops and Products 29, no. 1 (January 2009): 27–36. http://dx.doi.org/10.1016/j.indcrop.2008.03.013.

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50

Konn, Jonas, Lari Vähäsalo, Andrey Pranovich, and Bjarne Holmbom. "De-esterification and sulfonation in spruce CTMP: Effects on pulp and paper properties." Holzforschung 60, no. 4 (July 1, 2006): 355–64. http://dx.doi.org/10.1515/hf.2006.056.

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Abstract De-esterification and sulfonation reactions, which create new anionic groups in the middle lamella and primary wall layers, are the key chemical reactions in chemithermomechanical pulping. The effects of these reactions on the resulting fibre dimensions, refining energy demand, hand-sheet bulk and strength properties were assessed by laboratory-scale chemical pre-treatments and refining of Norway spruce chips. After pre-treatments with alkaline, sulfite, alkaline sulfite and alkaline peroxide liquors, a Wing defibrator-type batch refiner was used. The refining energy was measured. The degree of alkaline hydrolysis of acetyl and methyl ester groups in galactoglucomannans (GGMs) and pectins, and the degree of lignin sulfonation were determined. Hand-sheets were prepared and their physical properties were tested. The data were subjected to multivariate analysis and the order of significance of the chemical reactions towards pulp and paper properties was estimated. Chemical pre-treatments were found to increase the fibre length and the energy demand considerably. The fibre length and width after refining were strongly influenced by lignin sulfonation and pectin demethylation. GGM deacetylation had little influence on preserving the fibre dimensions in CTMP refining. The bulk, on the other hand, was highly influenced by GGM deacetylation. Peroxide reactions in alkaline peroxide treatments had no effect on the pulp and paper properties.

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Journal articles on the topic 'Sulfite pulping'

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