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Nabil Mameri - One of the best experts on this subject based on the ideXlab platform.
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Filtration of zinc ions utilising pretreated Streptomyces Rimosus biomass
Journal of Chemical Technology & Biotechnology, 2003Co-Authors: L Addour, D. Belhocine, André Pauss, Z Bakhti, H. Grib, Hakim Lounici, Dl Piron, Nabil MameriAbstract:The performance of biofiltration of zinc utilising pretreated Streptomyces Rimosus was studied. Streptomyces Rimosus biomass is able to bind zinc ions in batch mode. The biomass granules may be regenerated easily by using a biomass pretreatment which confers rigidity to biosolids, without decreasing the zinc uptake capacity, thus allowing collection of the biomass by filtration. Accordingly, biomass was pretreated with an anionic enzymatic tension active product (Extran AP41) and regeneration with a cleaning product (HCl) was successfully realised. It was shown that the optimum concentration of biomass and pressure range are found to be between 50 and 120 g dm−3 and 0.5 and 1 × 105 Pa, respectively. Complete regeneration was reached after three cycles under optimal experimental conditions when the biosorbent was saturated with synthetic ZnCl2 solution. The filterability of biosolids was demonstrated. A combination of a batch reactor and a filtration process made it possible to increase the performance of the complete treatment process. The biosorption capacity of the biomass to bind Zn ions was slightly increased (from X = 14 mg g−1 in batch mode to X = 16.1 mg g−1 in a process combining batch reactor and pressure filtration) and the experimental contact time was considerably reduced. Integration of the filtration process produced a dewatering cake which considerably facilitated the regeneration operation. Copyright © 2003 Society of Chemical Industry
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zinc uptake by Streptomyces Rimosus biomass using a packed bed column
Journal of Chemical Technology & Biotechnology, 1999Co-Authors: L Addour, D. Belhocine, N Boudries, Yves Comeau, André Pauss, Nabil MameriAbstract:The ability of Streptomyces Rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces Rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm -3 ) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mg Zn(II) g -1 biomass . This result was lower than the batch adsorption capacity of Streptomyces Rimosus, indicating that the packed-bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mg Zn(II) dm -3 on the biosorption capacity of the packed-bed was not significant. Biomass regeneration with 0.1 mol dm -3 HCl gave a 90% recovery of the adsorbed Zn(II).
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Zinc uptake by Streptomyces Rimosus biomass using a packed‐bed column
Journal of Chemical Technology & Biotechnology, 1999Co-Authors: L Addour, D. Belhocine, N Boudries, Yves Comeau, André Pauss, Nabil MameriAbstract:The ability of Streptomyces Rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces Rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm -3 ) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mg Zn(II) g -1 biomass . This result was lower than the batch adsorption capacity of Streptomyces Rimosus, indicating that the packed-bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mg Zn(II) dm -3 on the biosorption capacity of the packed-bed was not significant. Biomass regeneration with 0.1 mol dm -3 HCl gave a 90% recovery of the adsorbed Zn(II).
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Batch zinc biosorption by a bacterial nonliving Streptomyces Rimosus biomass
Water Research, 1999Co-Authors: Nabil Mameri, L Addour, D. Belhocine, N Boudries, H. Grib, Hakim Lounici, André PaussAbstract:Abstract The zinc biosorption capacity of a Streptomyces Rimosus biomass was studied in the batch mode. After a heat pretreatment, optimum conditions of biosorption were found to be: an average saturation contact time of 4 h, a biomass particle size between 140 and 250 μ m, the ambient temperature, a stirring speed of 250 rpm, and pH of 7.5. The equilibrium data could be fitted by a Langmuir isotherm equation. Under these optimal conditions, up to 30 mg Zn /g biomass , was fixed. Moreover, additional chemical treatment of the biomass by NaOH (1 mol/L), increased the biosorption capacity of about 80 mg Zn /g biomass .
A. Selatnia - One of the best experts on this subject based on the ideXlab platform.
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biosorption of ag from aqueous solution by Streptomyces Rimosus biomass
International Journal of Environment and Pollution, 2008Co-Authors: M.z. Bakhti, A. Selatnia, G.a. JunterAbstract:The silver biosorption capacity of a Streptomyces Rimosus biomass pretreated with NaOH was studied in the batch mode. Under optimal experimental conditions, a biosorption capacity of 63 mg Ag+ g−1 biomass was obtained. External mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data poorly fitted the Langmuir and Freundlich model isotherms over the whole range of initial silver concentrations tested (10-250 mg L−1).
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Biosorption of Ag+ from aqueous solution by Streptomyces Rimosus biomass
International Journal of Environment and Pollution, 2008Co-Authors: M.z. Bakhti, A. Selatnia, G.a. JunterAbstract:The silver biosorption capacity of a Streptomyces Rimosus biomass pretreated with NaOH was studied in the batch mode. Under optimal experimental conditions, a biosorption capacity of 63 mg Ag+ g−1 biomass was obtained. External mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data poorly fitted the Langmuir and Freundlich model isotherms over the whole range of initial silver concentrations tested (10-250 mg L−1).
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Simultaneous biosorption of Cu2+, Zn2+ and Cr6+ from aqueous solution by Streptomyces Rimosus biomass
Desalination, 2007Co-Authors: A Chergui, M.z. Bakhti, A. Selatnia, A. Chahboub, S. Haddoum, G.a. JunterAbstract:The Cu2+, Zn2+ and Cr6+ biosorption capacity of the Streptomyces Rimosus biomass pretreated with NaOH was studied in the batch mode. Under optimal experimental conditions, a biosorption capacity of 30 mg Cu2+ g–1 biomass, 27.4 mg Zn2+ g–1 biomass and 26.7 mg Cr6+ g–1 biomass was obtained. The equilibrium data poorly fitted the Langmuir and Freundlich model isotherms over the whole range of initial Cu2+, Zn2+ and Cr6+ concentrations tested (0–300 mg L–1).
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biosorption of cd2 from aqueous solution by a naoh treated bacterial dead Streptomyces Rimosus biomass
Hydrometallurgy, 2004Co-Authors: A. Selatnia, M.z. Bakhti, A Madani, L Kertous, Y MansouriAbstract:The cadmium biosorption capacity of a Streptomyces Rimosus biomass treated with NaOH (0.1 M) was studied in the batch mode. After pretreatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average saturation contact time of 1 h, a biomass concentration and a stirring speed in the range of 2.5–3 g L−1 and 200–250 rpm, respectively. The external mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions, a biosorption capacity of 63.3 mg Cd2+/g biomass was obtained.
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Biosorption of Ni2+ from aqueous solution by a NaOH-treated bacterial dead Streptomyces Rimosus biomass
Minerals Engineering, 2004Co-Authors: A. Selatnia, M.z. Bakhti, A Madani, L Kertous, Y Mansouri, Radia YousAbstract:Abstract The nickel biosorption capacity of a Streptomyces Rimosus biomass treated with NaOH (0.1 M) was studied in the batch mode. After pre-treatment of biomass at the ambient temperature, optimum conditions of biosorption were found to be: a biomass particle size between 50 and 160 μm, an average saturation contact time of 2 h, a biomass concentration of 3 g L −1 and a stirring speed of 250 rpm. The external mass transfer was found to be the controlling step in the overall sorption process. The equilibrium data could be fitted by Langmuir isotherm equation. Under these optimal conditions a biosorption capacity of 32.6 mg Ni 2+ /g biomass was obtained.
L Addour - One of the best experts on this subject based on the ideXlab platform.
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Filtration of zinc ions utilising pretreated Streptomyces Rimosus biomass
Journal of Chemical Technology & Biotechnology, 2003Co-Authors: L Addour, D. Belhocine, André Pauss, Z Bakhti, H. Grib, Hakim Lounici, Dl Piron, Nabil MameriAbstract:The performance of biofiltration of zinc utilising pretreated Streptomyces Rimosus was studied. Streptomyces Rimosus biomass is able to bind zinc ions in batch mode. The biomass granules may be regenerated easily by using a biomass pretreatment which confers rigidity to biosolids, without decreasing the zinc uptake capacity, thus allowing collection of the biomass by filtration. Accordingly, biomass was pretreated with an anionic enzymatic tension active product (Extran AP41) and regeneration with a cleaning product (HCl) was successfully realised. It was shown that the optimum concentration of biomass and pressure range are found to be between 50 and 120 g dm−3 and 0.5 and 1 × 105 Pa, respectively. Complete regeneration was reached after three cycles under optimal experimental conditions when the biosorbent was saturated with synthetic ZnCl2 solution. The filterability of biosolids was demonstrated. A combination of a batch reactor and a filtration process made it possible to increase the performance of the complete treatment process. The biosorption capacity of the biomass to bind Zn ions was slightly increased (from X = 14 mg g−1 in batch mode to X = 16.1 mg g−1 in a process combining batch reactor and pressure filtration) and the experimental contact time was considerably reduced. Integration of the filtration process produced a dewatering cake which considerably facilitated the regeneration operation. Copyright © 2003 Society of Chemical Industry
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zinc uptake by Streptomyces Rimosus biomass using a packed bed column
Journal of Chemical Technology & Biotechnology, 1999Co-Authors: L Addour, D. Belhocine, N Boudries, Yves Comeau, André Pauss, Nabil MameriAbstract:The ability of Streptomyces Rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces Rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm -3 ) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mg Zn(II) g -1 biomass . This result was lower than the batch adsorption capacity of Streptomyces Rimosus, indicating that the packed-bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mg Zn(II) dm -3 on the biosorption capacity of the packed-bed was not significant. Biomass regeneration with 0.1 mol dm -3 HCl gave a 90% recovery of the adsorbed Zn(II).
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Zinc uptake by Streptomyces Rimosus biomass using a packed‐bed column
Journal of Chemical Technology & Biotechnology, 1999Co-Authors: L Addour, D. Belhocine, N Boudries, Yves Comeau, André Pauss, Nabil MameriAbstract:The ability of Streptomyces Rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces Rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm -3 ) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mg Zn(II) g -1 biomass . This result was lower than the batch adsorption capacity of Streptomyces Rimosus, indicating that the packed-bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mg Zn(II) dm -3 on the biosorption capacity of the packed-bed was not significant. Biomass regeneration with 0.1 mol dm -3 HCl gave a 90% recovery of the adsorbed Zn(II).
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Batch zinc biosorption by a bacterial nonliving Streptomyces Rimosus biomass
Water Research, 1999Co-Authors: Nabil Mameri, L Addour, D. Belhocine, N Boudries, H. Grib, Hakim Lounici, André PaussAbstract:Abstract The zinc biosorption capacity of a Streptomyces Rimosus biomass was studied in the batch mode. After a heat pretreatment, optimum conditions of biosorption were found to be: an average saturation contact time of 4 h, a biomass particle size between 140 and 250 μ m, the ambient temperature, a stirring speed of 250 rpm, and pH of 7.5. The equilibrium data could be fitted by a Langmuir isotherm equation. Under these optimal conditions, up to 30 mg Zn /g biomass , was fixed. Moreover, additional chemical treatment of the biomass by NaOH (1 mol/L), increased the biosorption capacity of about 80 mg Zn /g biomass .
André Pauss - One of the best experts on this subject based on the ideXlab platform.
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Filtration of zinc ions utilising pretreated Streptomyces Rimosus biomass
Journal of Chemical Technology & Biotechnology, 2003Co-Authors: L Addour, D. Belhocine, André Pauss, Z Bakhti, H. Grib, Hakim Lounici, Dl Piron, Nabil MameriAbstract:The performance of biofiltration of zinc utilising pretreated Streptomyces Rimosus was studied. Streptomyces Rimosus biomass is able to bind zinc ions in batch mode. The biomass granules may be regenerated easily by using a biomass pretreatment which confers rigidity to biosolids, without decreasing the zinc uptake capacity, thus allowing collection of the biomass by filtration. Accordingly, biomass was pretreated with an anionic enzymatic tension active product (Extran AP41) and regeneration with a cleaning product (HCl) was successfully realised. It was shown that the optimum concentration of biomass and pressure range are found to be between 50 and 120 g dm−3 and 0.5 and 1 × 105 Pa, respectively. Complete regeneration was reached after three cycles under optimal experimental conditions when the biosorbent was saturated with synthetic ZnCl2 solution. The filterability of biosolids was demonstrated. A combination of a batch reactor and a filtration process made it possible to increase the performance of the complete treatment process. The biosorption capacity of the biomass to bind Zn ions was slightly increased (from X = 14 mg g−1 in batch mode to X = 16.1 mg g−1 in a process combining batch reactor and pressure filtration) and the experimental contact time was considerably reduced. Integration of the filtration process produced a dewatering cake which considerably facilitated the regeneration operation. Copyright © 2003 Society of Chemical Industry
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zinc uptake by Streptomyces Rimosus biomass using a packed bed column
Journal of Chemical Technology & Biotechnology, 1999Co-Authors: L Addour, D. Belhocine, N Boudries, Yves Comeau, André Pauss, Nabil MameriAbstract:The ability of Streptomyces Rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces Rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm -3 ) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mg Zn(II) g -1 biomass . This result was lower than the batch adsorption capacity of Streptomyces Rimosus, indicating that the packed-bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mg Zn(II) dm -3 on the biosorption capacity of the packed-bed was not significant. Biomass regeneration with 0.1 mol dm -3 HCl gave a 90% recovery of the adsorbed Zn(II).
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Zinc uptake by Streptomyces Rimosus biomass using a packed‐bed column
Journal of Chemical Technology & Biotechnology, 1999Co-Authors: L Addour, D. Belhocine, N Boudries, Yves Comeau, André Pauss, Nabil MameriAbstract:The ability of Streptomyces Rimosus biomass to bind zinc ions in batch mode was shown recently. The aim of this study was to determine the zinc uptake capacity by Streptomyces Rimosus biomass in continuous mode. Bacterial biomass was able to bind more Zn(II) after pretreatment with sodium hydroxide (1 mol dm -3 ) than without treatment. The maximum adsorption capacity and the adsorption capacity at the saturation point calculated by means of both the exchange zone model and the Thomas model were practically identical of about 2.9 mg Zn(II) g -1 biomass . This result was lower than the batch adsorption capacity of Streptomyces Rimosus, indicating that the packed-bed is not the most appropriate process to exploit the bacterial biomass adsorption capacity. The effect of zinc concentration in the range of 10 to 200 mg Zn(II) dm -3 on the biosorption capacity of the packed-bed was not significant. Biomass regeneration with 0.1 mol dm -3 HCl gave a 90% recovery of the adsorbed Zn(II).
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Batch zinc biosorption by a bacterial nonliving Streptomyces Rimosus biomass
Water Research, 1999Co-Authors: Nabil Mameri, L Addour, D. Belhocine, N Boudries, H. Grib, Hakim Lounici, André PaussAbstract:Abstract The zinc biosorption capacity of a Streptomyces Rimosus biomass was studied in the batch mode. After a heat pretreatment, optimum conditions of biosorption were found to be: an average saturation contact time of 4 h, a biomass particle size between 140 and 250 μ m, the ambient temperature, a stirring speed of 250 rpm, and pH of 7.5. The equilibrium data could be fitted by a Langmuir isotherm equation. Under these optimal conditions, up to 30 mg Zn /g biomass , was fixed. Moreover, additional chemical treatment of the biomass by NaOH (1 mol/L), increased the biosorption capacity of about 80 mg Zn /g biomass .
Nabih A. Baeshin - One of the best experts on this subject based on the ideXlab platform.
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The production of oxytetracycline in a date medium by different mutants of Streptomyces Rimosus induced by dry and wet heat
Bioresource Technology, 1993Co-Authors: Nabih A. Baeshin, Abou-zeid A. Abou-zeid, Ahmad O. BaghlafAbstract:Abstract Dry heat was more effective as a physical mutagen than wet heat in induction of Streptomyces Rimosus . The optimal temperature for inducing auxotrophic mutants in spores of Streptomyces Rimosus was 55°C under dry-treatment conditions. Only two mutants out of 138 dry- and wet-heat mutants produced higher antibiotic titres than the parent organism, and these were obtained after exposure of spores to dry heat at 45°C for 160 min.
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Utilization of date-seed lipid and hydrolysate in the fermentative formation of oxytetracycline by Streptomyces Rimosus
Bioresource Technology, 1992Co-Authors: Abou-zeid A. Abou-zeid, Abou-zied, Nabih A. BaeshinAbstract:Abstract Date-seed lipids and data-seed hydrolysate were investigated as carbon and nitrogen sources in the fermentation medium for the formation of oxytetracycline by Streptomyces Rimosus . It was found that date-seed lipids in a concentration of 70·0 mg/ml were a good carbon source and gave higher titres for the antibiotic than glucose. Date-seed lipids acted as carbon sources and antifoaming agents in the fermentation medium. It was also found that date-seed amino-acid hydrolysate in a concentration of 4·0 mg/ml was a suitable nitrogen source for the biosynthesis of oxytetracycline by Streptomyces Rimosus , and gave higher titres of the antibiotic than did urea.