Pub Date : 1998-08-01DOI: 10.1002/(SICI)1097-4660(199808)72:4<289::AID-JCTB905>3.0.CO;2-#
P. Vandevivere, R. Bianchi, W. Verstraete
New ecolabels for textile products and tighter restrictions on waste- water discharges are forcing textile wet processors to reuse process water and chemicals. This challenge has prompted intensive research in new advanced treatment technologies, some of which currently making their way to full-scale installations. These comprise polishing treatments such as -ltration, chemical oxidation and specialized Nocculation techniques and pre-treatment steps includ- ing anaerobic digestion, -xed--lm bioreactors, FentonIs reagent oxidation, elec- trolysis, or foam Notation. Though several of these new technologies are promising in terms of cost and performance, they all su†er limitations which require further research and/or need broader validation. A segment of the research deals with the separate handling of speci-c sub-streams such as dyebath effluents to which membrane -ltration is sometimes applied. The main limitation of this approach is the treatment of the concentrate stream. The spectrum of available technologies may, in the future, be further broadened to include oxidation, specialized bio-sorptive processes, solvent extrac- fungi/H 2 O 2 -driven tion, or photocatalysis. 1998 SCI ( J. Chem. T echnol. Biotechnol. 72, 289E302 (1998)
{"title":"Treatment and Reuse of Wastewater from the Textile Wet-Processing Industry : Review of Emerging Technologies","authors":"P. Vandevivere, R. Bianchi, W. Verstraete","doi":"10.1002/(SICI)1097-4660(199808)72:4<289::AID-JCTB905>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199808)72:4<289::AID-JCTB905>3.0.CO;2-#","url":null,"abstract":"New ecolabels for textile products and tighter restrictions on waste- water discharges are forcing textile wet processors to reuse process water and chemicals. This challenge has prompted intensive research in new advanced treatment technologies, some of which currently making their way to full-scale installations. These comprise polishing treatments such as -ltration, chemical oxidation and specialized Nocculation techniques and pre-treatment steps includ- ing anaerobic digestion, -xed--lm bioreactors, FentonIs reagent oxidation, elec- trolysis, or foam Notation. Though several of these new technologies are promising in terms of cost and performance, they all su†er limitations which require further research and/or need broader validation. A segment of the research deals with the separate handling of speci-c sub-streams such as dyebath effluents to which membrane -ltration is sometimes applied. The main limitation of this approach is the treatment of the concentrate stream. The spectrum of available technologies may, in the future, be further broadened to include oxidation, specialized bio-sorptive processes, solvent extrac- fungi/H 2 O 2 -driven tion, or photocatalysis. 1998 SCI ( J. Chem. T echnol. Biotechnol. 72, 289E302 (1998)","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86413941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1998-03-01DOI: 10.1002/(SICI)1097-4660(199803)71:3<241::AID-JCTB810>3.3.CO;2-7
J. Breccia, A. C. Morán, G. R. Castro, F. Siñeriz
Purified endo-β-1,4-xylanase of Bacillus amyloliquefaciens MIR 32 retained 100% of its activity after 4 days of incubation at 50°C. Sorbitol (400 mg cm -3 ) produced a 63-fold increase in the half-life of the enzyme at 65°C, which was only 29 min at this temperature in the absence of the polyol. This thermal stabilizing activity increased exponentially in respect to sorbitol concentration in the range 250-400 mg cm -3 and was dependent on the pH, showing a maximum at pH values between 5.25 and 8.0. The circular dichroism (CD) thermal scanning profile (50°C h -1 ) at 224 nm showed that changes in the secondary structure of xylanase started at 65°C, while in the presence of sorbitol (400 mg cm -3 ) these modifications started at 80°C. This study indicated that sorbitol might be a valuable stabilizer for the use of β-xylanase from B. amyloliquefaciens at high temperatures.
解淀粉芽孢杆菌MIR 32纯化后的内切β-1,4-木聚糖酶在50℃下孵育4天后仍保持100%的活性。山梨糖醇(400 mg cm -3)在65°C时使酶的半衰期增加63倍，在没有多元醇的情况下，该温度下仅为29分钟。在250-400 mg cm -3范围内，山梨醇的热稳定活性呈指数增长，并与pH值有关，pH值在5.25 - 8.0之间达到最大值。圆二色(CD)热扫描谱(50°C h -1)显示木聚糖酶二级结构的变化始于65°C，而山梨糖醇(400 mg cm -3)存在时，这些修饰始于80°C。该研究表明，山梨醇可能是一种有价值的高温稳定剂，用于解淀粉酵母β-木聚糖酶的利用。
{"title":"Thermal stabilization by polyols of β‐xylanase from Bacillus amyloliquefaciens","authors":"J. Breccia, A. C. Morán, G. R. Castro, F. Siñeriz","doi":"10.1002/(SICI)1097-4660(199803)71:3<241::AID-JCTB810>3.3.CO;2-7","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199803)71:3<241::AID-JCTB810>3.3.CO;2-7","url":null,"abstract":"Purified endo-β-1,4-xylanase of Bacillus amyloliquefaciens MIR 32 retained 100% of its activity after 4 days of incubation at 50°C. Sorbitol (400 mg cm -3 ) produced a 63-fold increase in the half-life of the enzyme at 65°C, which was only 29 min at this temperature in the absence of the polyol. This thermal stabilizing activity increased exponentially in respect to sorbitol concentration in the range 250-400 mg cm -3 and was dependent on the pH, showing a maximum at pH values between 5.25 and 8.0. The circular dichroism (CD) thermal scanning profile (50°C h -1 ) at 224 nm showed that changes in the secondary structure of xylanase started at 65°C, while in the presence of sorbitol (400 mg cm -3 ) these modifications started at 80°C. This study indicated that sorbitol might be a valuable stabilizer for the use of β-xylanase from B. amyloliquefaciens at high temperatures.","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86896832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1998-01-01DOI: 10.1002/(sici)1097-4660(199809)73:1<71::aid-jctb924>3.3.co;2-4
S. Barberis, J. C. Gentina
The influence of dissolved oxygen (% DO) on lactase production by Kluyveromyces fragilis (NRRL-Y-1109) in chemostat culture using a defined medium was studied. The aim was to determine conditions for both high specific enzyme activity and high volumetric enzyme productivity. Significant differences in the specific enzyme activity and specific and volumetric enzyme productivity were found at the corresponding steady states when the DO was varied between 0 and 90%. Maximum lactase production was attained at 10% DO. Under this condition the best results were an enzyme activity of 5910 IU g -1 , specific production rate of 1810 IU g -1 h -1 and volumetric production rate of 1530 IU dm -3 h -1 . This seem to be due to the fact that at low aeration conditions the yeast metabolism is more reductive and as a consequence it verifies both higher specific lactose consumption rate and higher enzyme expression than in full aeration conditions. The results of this investigation are also compared with those of other studies of lactase production by Kluyveromyces sp.
研究了溶解氧(% DO)对易碎克鲁维菌(NRRL-Y-1109)在固定培养基中产乳糖酶的影响。目的是确定高比酶活性和高体积酶产率的条件。当DO在0 ~ 90%范围内变化时，相应稳态下的比酶活性、比酶和体积酶产量均有显著差异。乳酸酶产量在10% DO时达到最大值。在此条件下，最佳酶活为5910 IU g -1，比产率为1810 IU g -1 h -1，体积产率为1530 IU dm -3 h -1。这似乎是由于在低曝气条件下酵母代谢更具还原性，因此它验证了比完全曝气条件下更高的特定乳糖消耗率和更高的酶表达。本研究结果还与克卢维酵母菌产乳糖酶的其他研究结果进行了比较。
{"title":"Effect of dissolved oxygen level on lactase production by Kluyveromyces fragilis","authors":"S. Barberis, J. C. Gentina","doi":"10.1002/(sici)1097-4660(199809)73:1<71::aid-jctb924>3.3.co;2-4","DOIUrl":"https://doi.org/10.1002/(sici)1097-4660(199809)73:1<71::aid-jctb924>3.3.co;2-4","url":null,"abstract":"The influence of dissolved oxygen (% DO) on lactase production by Kluyveromyces fragilis (NRRL-Y-1109) in chemostat culture using a defined medium was studied. The aim was to determine conditions for both high specific enzyme activity and high volumetric enzyme productivity. Significant differences in the specific enzyme activity and specific and volumetric enzyme productivity were found at the corresponding steady states when the DO was varied between 0 and 90%. Maximum lactase production was attained at 10% DO. Under this condition the best results were an enzyme activity of 5910 IU g -1 , specific production rate of 1810 IU g -1 h -1 and volumetric production rate of 1530 IU dm -3 h -1 . This seem to be due to the fact that at low aeration conditions the yeast metabolism is more reductive and as a consequence it verifies both higher specific lactose consumption rate and higher enzyme expression than in full aeration conditions. The results of this investigation are also compared with those of other studies of lactase production by Kluyveromyces sp.","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1998-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82828064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1997-12-01DOI: 10.1002/(SICI)1097-4660(199712)70:4<325::AID-JCTB767>3.0.CO;2-#
V. Choudhary, V. Rane
Influences of promoter concentration (or Sm/Mg ratio), precursor for MgO (viz. Mg-acetate, Mg-carbonate and Mg-hydroxide), calcination temperature of Sm-promoted MgO catalyst on the catalytic activity/selectivity in the oxidative coupling of methane (OCM) at different temperatures (650-850°C) and CH 4 /O 2 ratios in feed (2.0-8.0) at a high space velocity (51600 cm 3 /g.h) have been investigated. The catalytic activity/selectivity of Sm-MgO catalysts in the OCM are found to be strongly influenced by the Sm/Mg ratio, precursor used for MgO and catalyst calcination temperature. The catalyst with Sm/Mg ratio of 0.11, prepared using magnesium acetate and magnesium carbonate as a source of MgO and calcining at 950°C, is found to be highly active and selective in the OCM process. A drastic reduction in catalytic activity/selectivity is observed when the catalyst is supported on low surface area porous catalyst carriers, indicating strong catalyst-support interactions.
{"title":"Oxidative coupling of methane over Sm‐promoted MgO: Influence of composition and preparation conditions","authors":"V. Choudhary, V. Rane","doi":"10.1002/(SICI)1097-4660(199712)70:4<325::AID-JCTB767>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199712)70:4<325::AID-JCTB767>3.0.CO;2-#","url":null,"abstract":"Influences of promoter concentration (or Sm/Mg ratio), precursor for MgO (viz. Mg-acetate, Mg-carbonate and Mg-hydroxide), calcination temperature of Sm-promoted MgO catalyst on the catalytic activity/selectivity in the oxidative coupling of methane (OCM) at different temperatures (650-850°C) and CH 4 /O 2 ratios in feed (2.0-8.0) at a high space velocity (51600 cm 3 /g.h) have been investigated. The catalytic activity/selectivity of Sm-MgO catalysts in the OCM are found to be strongly influenced by the Sm/Mg ratio, precursor used for MgO and catalyst calcination temperature. The catalyst with Sm/Mg ratio of 0.11, prepared using magnesium acetate and magnesium carbonate as a source of MgO and calcining at 950°C, is found to be highly active and selective in the OCM process. A drastic reduction in catalytic activity/selectivity is observed when the catalyst is supported on low surface area porous catalyst carriers, indicating strong catalyst-support interactions.","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82222198","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1997-09-01DOI: 10.1002/(SICI)1097-4660(199709)70:1<45::AID-JCTB737>3.3.CO;2-F
S. Bossrez, J. Remacle, J. Coyette
The metal affinity of Enterococcus hirae cell walls and the relation to the chemical composition of the wall constituents were investigated, by studying the nickel absorption on purified cell walls of Enterococcus hirae mutants. The strains of Enterococcus hirae are characterised by their penicillin resistance, the mother strains ATCC9790, the penicillin-sensitive mutant AS21 and the penicillin-resistant mutant R40 present an MIC (minimum inhibitory concentration of penicillin) of 1-2, 0.075 and 80 μg cm -3 , respectively. Preliminary results showed that the penicillin-resistant cell wall (R40) had more affinity for nickel than the others. The maximum amount of fixed nickel average 2.03 μmol of Ni mg -1 of R40 cells walls, 1.06 μmol of Ni mg -1 of AS21 cell walls and 0.96 μmol of Ni mg -1 of ATCC cell walls. The Scatchard model showed at least two types of nickel fixation sites, with low and high affinity respectively, and a negative cooperativity between sites. Application of the BET isotherm implies a multilayer adsorption process in which one layer does not need to be completely saturated before the succeeding ones. The potentiometric titration curve showed the proton affinity distribution of the cell walls. Two protonation constants were obtained, one at pH 4.5 which corresponded to the pK a of a weak acid, and one at pH 7.2 which corresponded to the pK a of the couple of H 2 PO 4 - /HPO 4 2- .
{"title":"Adsorption of nickel on Enterococcus hirae cell walls","authors":"S. Bossrez, J. Remacle, J. Coyette","doi":"10.1002/(SICI)1097-4660(199709)70:1<45::AID-JCTB737>3.3.CO;2-F","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199709)70:1<45::AID-JCTB737>3.3.CO;2-F","url":null,"abstract":"The metal affinity of Enterococcus hirae cell walls and the relation to the chemical composition of the wall constituents were investigated, by studying the nickel absorption on purified cell walls of Enterococcus hirae mutants. The strains of Enterococcus hirae are characterised by their penicillin resistance, the mother strains ATCC9790, the penicillin-sensitive mutant AS21 and the penicillin-resistant mutant R40 present an MIC (minimum inhibitory concentration of penicillin) of 1-2, 0.075 and 80 μg cm -3 , respectively. Preliminary results showed that the penicillin-resistant cell wall (R40) had more affinity for nickel than the others. The maximum amount of fixed nickel average 2.03 μmol of Ni mg -1 of R40 cells walls, 1.06 μmol of Ni mg -1 of AS21 cell walls and 0.96 μmol of Ni mg -1 of ATCC cell walls. The Scatchard model showed at least two types of nickel fixation sites, with low and high affinity respectively, and a negative cooperativity between sites. Application of the BET isotherm implies a multilayer adsorption process in which one layer does not need to be completely saturated before the succeeding ones. The potentiometric titration curve showed the proton affinity distribution of the cell walls. Two protonation constants were obtained, one at pH 4.5 which corresponded to the pK a of a weak acid, and one at pH 7.2 which corresponded to the pK a of the couple of H 2 PO 4 - /HPO 4 2- .","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1997-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80158383","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-12-01DOI: 10.1002/(SICI)1097-4660(199612)67:4<345::AID-JCTB586>3.0.CO;2-#
Tsugio Sato, Ken-Ichi Sato, Y. Fujishiro, T. Yoshioka, A. Okuwaki
The photocatalytic activity of H2Ti4O9/CdS nanocomposites incorporating CdS particles, less than 0·8 nm thick, in the interlayer of H2Ti4O9 was evaluated for the reduction of NO3− with and without methanol. NO3− was photochemically reduced by bandgap illumination in the presence of H2Ti4O9/CdS nanocomposites with and without methanol although unsupported CdS showed no noticeable photocatalytic activity for NO3− reduction. The oxidation of CdS in H2Ti4O9/CdS to SO42- was accompanied by NO3− reduction without methanol, whereas addition of methanol was useful to promote the NO3− reduction and depress the oxidation of CdS. The catalytic activity of H2Ti4O9/CdS greatly increased with doping Pt particles in the interlayer.
{"title":"Photochemical reduction of nitrate to ammonia using layered hydrous titanate/cadmium sulphide nanocomposites","authors":"Tsugio Sato, Ken-Ichi Sato, Y. Fujishiro, T. Yoshioka, A. Okuwaki","doi":"10.1002/(SICI)1097-4660(199612)67:4<345::AID-JCTB586>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199612)67:4<345::AID-JCTB586>3.0.CO;2-#","url":null,"abstract":"The photocatalytic activity of H2Ti4O9/CdS nanocomposites incorporating CdS particles, less than 0·8 nm thick, in the interlayer of H2Ti4O9 was evaluated for the reduction of NO3− with and without methanol. NO3− was photochemically reduced by bandgap illumination in the presence of H2Ti4O9/CdS nanocomposites with and without methanol although unsupported CdS showed no noticeable photocatalytic activity for NO3− reduction. The oxidation of CdS in H2Ti4O9/CdS to SO42- was accompanied by NO3− reduction without methanol, whereas addition of methanol was useful to promote the NO3− reduction and depress the oxidation of CdS. The catalytic activity of H2Ti4O9/CdS greatly increased with doping Pt particles in the interlayer.","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84967253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-12-01DOI: 10.1002/(SICI)1097-4660(199612)67:4<413::AID-JCTB544>3.3.CO;2-A
N. Shah
{"title":"Book Review Loss prevention and safety promotion in the process industries, Volumes I & II Proceedings of the 8th International Symposium, Antwerp, Belgium, June 69, 1995.","authors":"N. Shah","doi":"10.1002/(SICI)1097-4660(199612)67:4<413::AID-JCTB544>3.3.CO;2-A","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199612)67:4<413::AID-JCTB544>3.3.CO;2-A","url":null,"abstract":"","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78380247","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 1996-10-01DOI: 10.1002/(SICI)1097-4660(199610)67:2<214::AID-JCTB5555>3.0.CO;2-#
J. Winterbottom
{"title":"Book Review The encyclopedia of chemical technology KirkOthmer, Vols 9, 10 and 11.","authors":"J. Winterbottom","doi":"10.1002/(SICI)1097-4660(199610)67:2<214::AID-JCTB5555>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1097-4660(199610)67:2<214::AID-JCTB5555>3.0.CO;2-#","url":null,"abstract":"","PeriodicalId":15303,"journal":{"name":"Journal of Chemical Technology & Biotechnology","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"1996-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74582214","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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