The Experts below are selected from a list of 19008 Experts worldwide ranked by ideXlab platform
Zhiqiang Zhang - One of the best experts on this subject based on the ideXlab platform.
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copper ii adsorption by the Extracellular Polymeric Substance extracted from waste activated sludge after short time aerobic digestion
Environmental Science and Pollution Research, 2014Co-Authors: Zhiqiang Zhang, Yun Zhou, Jiao ZhangAbstract:The Extracellular Polymeric Substance (EPS) extracted from waste activated sludge (WAS) after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cu2+ removal from water. The EPS consisted of protein (52.6 %, w/w), polysaccharide (30.7 %, w/w), and nucleic acid (16.7 %, w/w). Short-time aerobic digestion process of WAS for about 4 h promoted the productivity growth of the EPS for about 10 %. With a molecular weight of about 1.9 × 106 Da, the EPS showed a linear structure with long chains, and contained carboxyl, hydroxyl, and amino groups. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (700.3 mg Cu2+/g EPS) was markedly greater than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the complex results of multiple analytical techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy, etc., the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cu2+ is the major mechanism.
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characteristics of cadmium ii adsorbed by the Extracellular Polymeric Substance extracted from waste activated sludge after short time aerobic digestion
Water Air and Soil Pollution, 2014Co-Authors: Zhiqiang Zhang, Jiao ZhangAbstract:The Extracellular Polymeric Substance (EPS) extracted from waste-activated sludge after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cd2+ removal from water. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (430.3 mg Cd2+/g EPS) was markedly higher than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the results of multiple analytical techniques, the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cd2+ was the major mechanism.
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a novel biosorbent for dye removal Extracellular Polymeric Substance eps of proteus mirabilis tj 1
Journal of Hazardous Materials, 2009Co-Authors: Zhiqiang Zhang, Xuejiang Wang, Aming Yang, Bin Xu, Ling Chen, Jianfu Zhao, Nicole Jaffrezicrenault, Didier LeonardAbstract:Abstract This paper deals with the Extracellular Polymeric Substance (EPS) of Proteus mirabilis TJ-1 used as a novel biosorbent to remove dye from aqueous solution in batch systems. As a widely used and hazardous dye, basic blue 54 (BB54) was chosen as the model dye to examine the adsorption performance of the EPS. The effects of pH, initial dye concentration, contact time and temperature on the sorption of BB54 to the EPS were examined. At various initial dye concentrations (50–400 mg/L), the batch sorption equilibrium can be obtained in only 5 min. Kinetic studies suggested that the sorption followed the internal transport mechanism. According to the Langmuir model, the maximum BB54 uptake of 2.005 g/g was obtained. Chemical analysis of the EPS indicated the presence of protein (30.9%, w/w) and acid polysaccharide (63.1%, w/w). Scanning electron microscopy (SEM) images showed that the EPS with a crystal-linear structure was whole enwrapped by adsorbed dye molecules. FTIR spectrum result revealed the presence of adsorbing groups such as carboxyl, hydroxyl and amino groups in the EPS. High-molecular weight of the EPS with more binding-sites and stronger van der Waals forces together with its specific construct leads to the excellent performance of dye adsorption. The EPS shows potential board application as a biosorbent for both environmental protection and dye recovery.
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a novel biosorbent for dye removal Extracellular Polymeric Substance eps of proteus mirabilis tj 1
Journal of Hazardous Materials, 2009Co-Authors: Zhiqiang Zhang, Siqing Xia, Xuejiang Wang, Aming Yang, Bin Xu, Ling Chen, Zhiliang Zhu, Jianfu Zhao, Nicole JaffrezicrenaultAbstract:This paper deals with the Extracellular Polymeric Substance (EPS) of Proteus mirabilis TJ-1 used as a novel biosorbent to remove dye from aqueous solution in batch systems. As a widely used and hazardous dye, basic blue 54 (BB54) was chosen as the model dye to examine the adsorption performance of the EPS. The effects of pH, initial dye concentration, contact time and temperature on the sorption of BB54 to the EPS were examined. At various initial dye concentrations (50–400 mg/L), the batch sorption equilibrium can be obtained in only 5 min. Kinetic studies suggested that the sorption followed the internal transport mechanism. According to the Langmuir model, the maximum BB54 uptake of 2.005 g/g was obtained. Chemical analysis of the EPS indicated the presence of protein (30.9%, w/w) and acid polysaccharide (63.1%, w/w). Scanning electron microscopy (SEM) images showed that the EPS with a crystal-linear structure was whole enwrapped by adsorbed dye molecules. FTIR spectrum result revealed the presence of adsorbing groups such as carboxyl, hydroxyl and amino groups in the EPS. High-molecular weight of the EPS with more binding-sites and stronger van der Waals forces together with its specific construct leads to the excellent performance of dye adsorption. The EPS shows potential board application as a biosorbent for both environmental protection and dye recovery. © 2008 Elsevier B.V. All rights reserved.
Jiao Zhang - One of the best experts on this subject based on the ideXlab platform.
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copper ii adsorption by the Extracellular Polymeric Substance extracted from waste activated sludge after short time aerobic digestion
Environmental Science and Pollution Research, 2014Co-Authors: Zhiqiang Zhang, Yun Zhou, Jiao ZhangAbstract:The Extracellular Polymeric Substance (EPS) extracted from waste activated sludge (WAS) after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cu2+ removal from water. The EPS consisted of protein (52.6 %, w/w), polysaccharide (30.7 %, w/w), and nucleic acid (16.7 %, w/w). Short-time aerobic digestion process of WAS for about 4 h promoted the productivity growth of the EPS for about 10 %. With a molecular weight of about 1.9 × 106 Da, the EPS showed a linear structure with long chains, and contained carboxyl, hydroxyl, and amino groups. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (700.3 mg Cu2+/g EPS) was markedly greater than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the complex results of multiple analytical techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy, etc., the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cu2+ is the major mechanism.
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characteristics of cadmium ii adsorbed by the Extracellular Polymeric Substance extracted from waste activated sludge after short time aerobic digestion
Water Air and Soil Pollution, 2014Co-Authors: Zhiqiang Zhang, Jiao ZhangAbstract:The Extracellular Polymeric Substance (EPS) extracted from waste-activated sludge after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cd2+ removal from water. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (430.3 mg Cd2+/g EPS) was markedly higher than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the results of multiple analytical techniques, the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cd2+ was the major mechanism.
Yun Zhou - One of the best experts on this subject based on the ideXlab platform.
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copper ii adsorption by the Extracellular Polymeric Substance extracted from waste activated sludge after short time aerobic digestion
Environmental Science and Pollution Research, 2014Co-Authors: Zhiqiang Zhang, Yun Zhou, Jiao ZhangAbstract:The Extracellular Polymeric Substance (EPS) extracted from waste activated sludge (WAS) after short-time aerobic digestion was investigated to be used as a novel biosorbent for Cu2+ removal from water. The EPS consisted of protein (52.6 %, w/w), polysaccharide (30.7 %, w/w), and nucleic acid (16.7 %, w/w). Short-time aerobic digestion process of WAS for about 4 h promoted the productivity growth of the EPS for about 10 %. With a molecular weight of about 1.9 × 106 Da, the EPS showed a linear structure with long chains, and contained carboxyl, hydroxyl, and amino groups. The sorption kinetics was well fit for the pseudo-second-order model, and the maximum sorption capacity of the EPS (700.3 mg Cu2+/g EPS) was markedly greater than those of the reported biosorbents. Both Langmuir model and Freundlich model commendably described the sorption isotherm. The Gibbs free energy analysis of the adsorption showed that the sorption process was feasible and spontaneous. According to the complex results of multiple analytical techniques, including scanning electron microscopy, Fourier transform infrared spectroscopy, atomic force microscopy, etc., the adsorption process took place via both physical and chemical sorption, but the electrostatic interaction between sorption sites with the functional groups and Cu2+ is the major mechanism.
Rajesh J Banu - One of the best experts on this subject based on the ideXlab platform.
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enhancing aerobic digestion potential of municipal waste activated sludge through removal of Extracellular Polymeric Substance
Environmental Science and Pollution Research, 2014Co-Authors: J Merrylin, Ick Tae Yeom, S Kaliappan, Adish S Kumar, Rajesh J BanuAbstract:A protease-secreting bacteria was used to pretreat municipal sewage sludge to enhance aerobic digestion. To enhance the accessibility of the sludge to the enzyme, Extracellular Polymeric Substances were removed using citric acid thereby removing the flocs in the sludge. The conditions for the bacterial pretreatment were optimized using response surface methodology. The results of the bacterial pretreatment indicated that the suspended solids reduction was 18 % in sludge treated with citric acid and 10 % in sludge not treated with citric acid whereas in raw sludge, suspended solids reduction was 5.3 %. Solubilization was 10.9 % in the sludge with Extracellular Polymeric Substances removed in contrast to that of the sludge with Extracellular Polymeric Substances, which was 7.2 %, and that of the raw sludge, which was just 4.8 %. The suspended solids reduction in the aerobic reactor containing pretreated sludge was 52.4 % whereas that in the control reactor was 15.3 %. Thus, pretreatment with the protease-secreting bacteria after the removal of Extracellular Polymeric Substances is a cost-effective and environmentally friendly method.
Jiaokun Li - One of the best experts on this subject based on the ideXlab platform.
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Role of Extracellular Polymeric Substance (EPS) in toxicity response of soil bacteria Bacillus sp. S3 to multiple heavy metals
Bioprocess and Biosystems Engineering, 2019Co-Authors: Weimin Zeng, Chenchen Wu, Runlan Yu, Yuandong Liu, Guanzhou Qiu, Xueling Wu, Fang Li, Li Shen, Jiaokun LiAbstract:Heavy metal resistant bacteria are of great interest because of their potential use in bioremediation. Understanding the survival and adaptive strategies of these bacteria under heavy metal stress is important for better utilization of these bacteria in remediation. The objective of this study was to investigate the role of bacterial Extracellular Polymeric Substance (EPS) in detoxifying against different heavy metals in Bacillus sp. S3, a new hyper antimony-oxidizing bacterium previously isolated from contaminated mine soils. The results showed that Bacillus sp. S3 is a multi-metal resistant bacterial strain, especially to Sb(III), Cu(II) and Cr(VI). Toxic Cd(II), Cr(VI) and Cu(II) could stimulate the secretion of EPS in Bacillus sp. S3, significantly enhancing the adsorption and detoxification capacity of heavy metals. Both Fourier transform infrared spectroscopy (FTIR) and three-dimensional excitation–emission matrix (3D-EEM) analysis further confirmed that proteins were the main compounds of EPS for metal binding. In contrast, the EPS production was not induced under Sb(III) stress. Furthermore, the TEM–EDX micrograph showed that Bacillus sp. S3 strain preferentially transported the Sb(III) to the inside of the cell rather than adsorbed it on the Extracellular surface, indicating intracellular detoxification rather than Extracellular EPS precipitation played an important role in microbial resistance towards Sb(III). Together, our study suggests that the toxicity response of EPS to heavy metals is associated with difference in EPS properties, metal types and corresponding environmental conditions, which is likely to contribute to microbial-mediated remediation.
