The Experts below are selected from a list of 315 Experts worldwide ranked by ideXlab platform
Chen Yang - One of the best experts on this subject based on the ideXlab platform.
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Effect of ions on Sorption of tylosin on clay minerals
RSC Advances, 2016Co-Authors: Qian Zhang, Xiaohua Shu, Xuetao Guo, Shiguang Wei, Chen YangAbstract:A widely used veterinary antibiotic tylosin is associated with a fast increase in the prevalence of genes for macrolide resistance. Therefore, there are growing concerns of its potentially adverse effects on natural ecosystems, and a study on the Sorption of tylosin is an important step in this direction. As a weak base, prior studies pointed out that cation exchange was the main Sorption mechanism for tylosin in soil, and minerals were important factors in influencing the Sorption. However, the ionic effect on the tylosin Sorption process on minerals has not been systematically conducted. In this study, the Sorption of tylosin on pure clay minerals was investigated in different ionic strength solutions. Moreover, the interlayer interaction of tylosin on different types of montmorillonite was preliminarily studied. All of the Sorption data were fitted with the Langmuir–Freundlich–Hill Sorption model. The results showed that the variation tendency of tylosin Sorption capacity on montmorillonite and kaolinite were nearly the same. The Sorption capacity of tylosin at different ionic strengths decreased with the order: 0.008 M > 0.051 M > 0.108 M > 0.508 M. In different ion solutions, the Sorption capacity of tylosin decreased in the following order: K+ > Na+ > Ca2+ Mg2+. However, the Sorption of tylosin on montmorillonite at low initial concentration of tylosin displayed a different tendency. When the initial concentration of tylosin was low, its Sorption capacities on montmorillonite at different ionic strengths decreased with the order: 0.051 M 0.108 M > 0.008 M > 0.508 M. For different ionic solutions, the Sorption of tylosin decreased in the order of Mg2+ Ca2+ > K+ > Na+. The cation effect on tylosin Sorption in the interlayers of montmorillonite was also investigated. The Sorption of tylosin on different montmorillonites decreased in the order of Ca-montmorillonite > Na-montmorillonite > K-montmorillonite. These indicated that the hydration of inorganic ions influenced the Sorption of tylosin. The results provide a more comprehensive understanding about the Sorption of tylosin on minerals.
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Sorption behavior of tylosin and sulfamethazine on humic acid kinetic and thermodynamic studies
RSC Advances, 2015Co-Authors: Xuetao Guo, Chen Yang, Zhi Dang, Shaomin LiuAbstract:With the aim to investigate the kinetics and thermodynamics of tylosin (TYL) and sulfamethazine (SMT) Sorption on humic acid (HA), batch Sorption experiments were performed using batch reactor systems. The results indicated that the Freundlich model was much more suitable for explaining the Sorption of TYL/SMT on HA, where the Sorption rates for TYL/SMT decreased with the initial concentration and the Sorption equilibrium could be attained within 24 h. Based on the intraparticle diffusion model, the Sorption process of TYL and SMT on HA could be divided into the fast Sorption stage and the slow Sorption stage. The kinetic data were well-fitted to the compartment pseudo first order model, where both surface diffusion and intraparticle diffusion may play an important role in rate-controlling processes. At a specific aqueous concentration, the single-point Sorption distribution coefficient (kd) of TYL and SMT decreased when the solution pH and ionic strength increased, which suggested that the Sorption of TYL and SMT on HA might be dominated by both ion exchange, surface complexation and hydrophobic interactions. Meanwhile, thermodynamic calculations of Sorption of TYL and SMT on HA revealed that the Sorption was endothermic and spontaneous at different temperatures and the transportation abilities of TYL and SMT might be weak for soils rich in HA.
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Sorption thermodynamics and kinetics properties of tylosin and sulfamethazine on goethite
Chemical Engineering Journal, 2013Co-Authors: Xuetao Guo, Qian Zhang, Chen Yang, Zhi Dang, Qingyu MengAbstract:Abstract In order to understand the Sorption processes of tylosin (TYL) and sulfamethazine (SMT) on soils, the Sorption thermodynamics and kinetics properties of two chemicals on goethite were investigated through Sorption equilibrium and Sorption rate experiments. The results showed that the Sorption of TYL and SMT were nonlinear and the Sorption capacities were influenced by the pH conditions of solution. The Sorption rates for TYL and SMT decreased as the initial concentration increased. The Sorption process might be constituted with the initial boundary layer diffusion or external surface, then the intraparticle diffusion or pore diffusion stage and finally equilibrium stage related with the Sorption on the interior surface of sorbent. Thermodynamic calculations of Sorption of TYL and SMT on goethite revealed that the Sorption of TYL on goethite was exothermal and spontaneous and SMT was endothermic and spontaneous. The results indicated that the transportation abilities of TYL and SMT might be weak for the soils rich in iron oxide. The significant differences in the Sorption behavior of two chemicals might be related with their physicochemical properties and suggested that the Sorption mechanisms of TYL and SMT on goethite would be complicated and the domain Sorption mechanism for each chemical at different pH conditions would be variable. It should be noted to assess the environmental risks of TYL and SMT.
Xuetao Guo - One of the best experts on this subject based on the ideXlab platform.
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Effect of ions on Sorption of tylosin on clay minerals
RSC Advances, 2016Co-Authors: Qian Zhang, Xiaohua Shu, Xuetao Guo, Shiguang Wei, Chen YangAbstract:A widely used veterinary antibiotic tylosin is associated with a fast increase in the prevalence of genes for macrolide resistance. Therefore, there are growing concerns of its potentially adverse effects on natural ecosystems, and a study on the Sorption of tylosin is an important step in this direction. As a weak base, prior studies pointed out that cation exchange was the main Sorption mechanism for tylosin in soil, and minerals were important factors in influencing the Sorption. However, the ionic effect on the tylosin Sorption process on minerals has not been systematically conducted. In this study, the Sorption of tylosin on pure clay minerals was investigated in different ionic strength solutions. Moreover, the interlayer interaction of tylosin on different types of montmorillonite was preliminarily studied. All of the Sorption data were fitted with the Langmuir–Freundlich–Hill Sorption model. The results showed that the variation tendency of tylosin Sorption capacity on montmorillonite and kaolinite were nearly the same. The Sorption capacity of tylosin at different ionic strengths decreased with the order: 0.008 M > 0.051 M > 0.108 M > 0.508 M. In different ion solutions, the Sorption capacity of tylosin decreased in the following order: K+ > Na+ > Ca2+ Mg2+. However, the Sorption of tylosin on montmorillonite at low initial concentration of tylosin displayed a different tendency. When the initial concentration of tylosin was low, its Sorption capacities on montmorillonite at different ionic strengths decreased with the order: 0.051 M 0.108 M > 0.008 M > 0.508 M. For different ionic solutions, the Sorption of tylosin decreased in the order of Mg2+ Ca2+ > K+ > Na+. The cation effect on tylosin Sorption in the interlayers of montmorillonite was also investigated. The Sorption of tylosin on different montmorillonites decreased in the order of Ca-montmorillonite > Na-montmorillonite > K-montmorillonite. These indicated that the hydration of inorganic ions influenced the Sorption of tylosin. The results provide a more comprehensive understanding about the Sorption of tylosin on minerals.
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Sorption behavior of tylosin and sulfamethazine on humic acid kinetic and thermodynamic studies
RSC Advances, 2015Co-Authors: Xuetao Guo, Chen Yang, Zhi Dang, Shaomin LiuAbstract:With the aim to investigate the kinetics and thermodynamics of tylosin (TYL) and sulfamethazine (SMT) Sorption on humic acid (HA), batch Sorption experiments were performed using batch reactor systems. The results indicated that the Freundlich model was much more suitable for explaining the Sorption of TYL/SMT on HA, where the Sorption rates for TYL/SMT decreased with the initial concentration and the Sorption equilibrium could be attained within 24 h. Based on the intraparticle diffusion model, the Sorption process of TYL and SMT on HA could be divided into the fast Sorption stage and the slow Sorption stage. The kinetic data were well-fitted to the compartment pseudo first order model, where both surface diffusion and intraparticle diffusion may play an important role in rate-controlling processes. At a specific aqueous concentration, the single-point Sorption distribution coefficient (kd) of TYL and SMT decreased when the solution pH and ionic strength increased, which suggested that the Sorption of TYL and SMT on HA might be dominated by both ion exchange, surface complexation and hydrophobic interactions. Meanwhile, thermodynamic calculations of Sorption of TYL and SMT on HA revealed that the Sorption was endothermic and spontaneous at different temperatures and the transportation abilities of TYL and SMT might be weak for soils rich in HA.
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Sorption thermodynamics and kinetics properties of tylosin and sulfamethazine on goethite
Chemical Engineering Journal, 2013Co-Authors: Xuetao Guo, Qian Zhang, Chen Yang, Zhi Dang, Qingyu MengAbstract:Abstract In order to understand the Sorption processes of tylosin (TYL) and sulfamethazine (SMT) on soils, the Sorption thermodynamics and kinetics properties of two chemicals on goethite were investigated through Sorption equilibrium and Sorption rate experiments. The results showed that the Sorption of TYL and SMT were nonlinear and the Sorption capacities were influenced by the pH conditions of solution. The Sorption rates for TYL and SMT decreased as the initial concentration increased. The Sorption process might be constituted with the initial boundary layer diffusion or external surface, then the intraparticle diffusion or pore diffusion stage and finally equilibrium stage related with the Sorption on the interior surface of sorbent. Thermodynamic calculations of Sorption of TYL and SMT on goethite revealed that the Sorption of TYL on goethite was exothermal and spontaneous and SMT was endothermic and spontaneous. The results indicated that the transportation abilities of TYL and SMT might be weak for the soils rich in iron oxide. The significant differences in the Sorption behavior of two chemicals might be related with their physicochemical properties and suggested that the Sorption mechanisms of TYL and SMT on goethite would be complicated and the domain Sorption mechanism for each chemical at different pH conditions would be variable. It should be noted to assess the environmental risks of TYL and SMT.
Baoshan Xing - One of the best experts on this subject based on the ideXlab platform.
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phenanthrene Sorption deSorption sequences provide new insight to explain high Sorption coefficients in field studies
Chemosphere, 2011Co-Authors: Bo Pan, Shu Tao, Di Zhang, Hongbo Peng, Baoshan XingAbstract:The Sorption coefficients obtained in field investigation vary greatly from laboratory Sorption experiments. The possible reasons were discussed in literature. Observing the commonly reported deSorption hysteresis, this study proposed that the unclear Sorption history of the field study could also result in the diverse Sorption coefficients. This study conducted a comparative study regarding phenanthrene Sorption/deSorption behavior in low-concentration multi-time Sorption process and the commonly applied high-concentration one-time Sorption process. The Sorption coefficients determined during the deSorption process were much higher than those at Sorption process. Thus, the prediction of Sorption coefficient should be related with Sorption history. DeSorption hysteresis was increased with increased equilibration time and decreased solid-phase concentration. In addition, although the apparent contact time between sorbate and sorbent was shorter for low-concentration multi-time Sorption, the deSorption hysteresis was much stronger, which consequently result in higher Sorption coefficients in comparison to high-concentration one-time Sorption. Pore swelling or diffusion-controlled Sorption kinetics could not explain this phenomenon. This study calls for research attention on Sorption history, especially for field investigations.
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Sorption mechanisms of phenanthrene lindane and atrazine with various humic acid fractions from a single soil sample
Environmental Science & Technology, 2011Co-Authors: Xilong Wang, Yu Yang, Baoshan XingAbstract:The Sorption behavior of organic compounds (phenanthrene, lindane, and atrazine) to sequentially extracted humic acids and humin from a peat soil was examined. The elemental composition, XPS and (13)C NMR data of sorbents combined with Sorption isotherm data of the tested compounds show that nonspecific interactions govern Sorption of phenanthrene and lindane by humic substances. Their Sorption is dependent on surface and bulk alkyl carbon contents of the sorbents, rather than aromatic carbon. Sorption of atrazine by these sorbents, however, is regulated by polar interactions (e.g., hydrogen bonding). Carboxylic and phenolic moieties are key components for H-bonding formation. Thermal analysis reveals that Sorption of apolar (i.e., phenanthrene and lindane) and polar (i.e., atrazine) compounds by humic substances exhibit dissimilar relationships with condensation and thermal stability of Sorption domains, emphasizing the major influence of domain spatial arrangement on Sorption of organic compounds with distinct polarity. Results of pH-dependent Sorption indicate that reduction in Sorption of atrazine by the tested sorbents is more evident than phenanthrene with increasing pH, supporting the dependence of organic compound Sorption on its polarity and structure. This study highlights the different interaction mechanisms of apolar and polar organic compounds with humic substances.
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Phenanthrene Sorption/deSorption sequences provide new insight to explain high Sorption coefficients in field studies.
Chemosphere, 2011Co-Authors: Bo Pan, Shu Tao, Di Zhang, Hongbo Peng, Baoshan XingAbstract:The Sorption coefficients obtained in field investigation vary greatly from laboratory Sorption experiments. The possible reasons were discussed in literature. Observing the commonly reported deSorption hysteresis, this study proposed that the unclear Sorption history of the field study could also result in the diverse Sorption coefficients. This study conducted a comparative study regarding phenanthrene Sorption/deSorption behavior in low-concentration multi-time Sorption process and the commonly applied high-concentration one-time Sorption process. The Sorption coefficients determined during the deSorption process were much higher than those at Sorption process. Thus, the prediction of Sorption coefficient should be related with Sorption history. DeSorption hysteresis was increased with increased equilibration time and decreased solid-phase concentration. In addition, although the apparent contact time between sorbate and sorbent was shorter for low-concentration multi-time Sorption, the deSorption hysteresis was much stronger, which consequently result in higher Sorption coefficients in comparison to high-concentration one-time Sorption. Pore swelling or diffusion-controlled Sorption kinetics could not explain this phenomenon. This study calls for research attention on Sorption history, especially for field investigations.
Shaomin Liu - One of the best experts on this subject based on the ideXlab platform.
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Sorption behavior of tylosin and sulfamethazine on humic acid kinetic and thermodynamic studies
RSC Advances, 2015Co-Authors: Xuetao Guo, Chen Yang, Zhi Dang, Shaomin LiuAbstract:With the aim to investigate the kinetics and thermodynamics of tylosin (TYL) and sulfamethazine (SMT) Sorption on humic acid (HA), batch Sorption experiments were performed using batch reactor systems. The results indicated that the Freundlich model was much more suitable for explaining the Sorption of TYL/SMT on HA, where the Sorption rates for TYL/SMT decreased with the initial concentration and the Sorption equilibrium could be attained within 24 h. Based on the intraparticle diffusion model, the Sorption process of TYL and SMT on HA could be divided into the fast Sorption stage and the slow Sorption stage. The kinetic data were well-fitted to the compartment pseudo first order model, where both surface diffusion and intraparticle diffusion may play an important role in rate-controlling processes. At a specific aqueous concentration, the single-point Sorption distribution coefficient (kd) of TYL and SMT decreased when the solution pH and ionic strength increased, which suggested that the Sorption of TYL and SMT on HA might be dominated by both ion exchange, surface complexation and hydrophobic interactions. Meanwhile, thermodynamic calculations of Sorption of TYL and SMT on HA revealed that the Sorption was endothermic and spontaneous at different temperatures and the transportation abilities of TYL and SMT might be weak for soils rich in HA.
Qian Zhang - One of the best experts on this subject based on the ideXlab platform.
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Effect of ions on Sorption of tylosin on clay minerals
RSC Advances, 2016Co-Authors: Qian Zhang, Xiaohua Shu, Xuetao Guo, Shiguang Wei, Chen YangAbstract:A widely used veterinary antibiotic tylosin is associated with a fast increase in the prevalence of genes for macrolide resistance. Therefore, there are growing concerns of its potentially adverse effects on natural ecosystems, and a study on the Sorption of tylosin is an important step in this direction. As a weak base, prior studies pointed out that cation exchange was the main Sorption mechanism for tylosin in soil, and minerals were important factors in influencing the Sorption. However, the ionic effect on the tylosin Sorption process on minerals has not been systematically conducted. In this study, the Sorption of tylosin on pure clay minerals was investigated in different ionic strength solutions. Moreover, the interlayer interaction of tylosin on different types of montmorillonite was preliminarily studied. All of the Sorption data were fitted with the Langmuir–Freundlich–Hill Sorption model. The results showed that the variation tendency of tylosin Sorption capacity on montmorillonite and kaolinite were nearly the same. The Sorption capacity of tylosin at different ionic strengths decreased with the order: 0.008 M > 0.051 M > 0.108 M > 0.508 M. In different ion solutions, the Sorption capacity of tylosin decreased in the following order: K+ > Na+ > Ca2+ Mg2+. However, the Sorption of tylosin on montmorillonite at low initial concentration of tylosin displayed a different tendency. When the initial concentration of tylosin was low, its Sorption capacities on montmorillonite at different ionic strengths decreased with the order: 0.051 M 0.108 M > 0.008 M > 0.508 M. For different ionic solutions, the Sorption of tylosin decreased in the order of Mg2+ Ca2+ > K+ > Na+. The cation effect on tylosin Sorption in the interlayers of montmorillonite was also investigated. The Sorption of tylosin on different montmorillonites decreased in the order of Ca-montmorillonite > Na-montmorillonite > K-montmorillonite. These indicated that the hydration of inorganic ions influenced the Sorption of tylosin. The results provide a more comprehensive understanding about the Sorption of tylosin on minerals.
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Sorption thermodynamics and kinetics properties of tylosin and sulfamethazine on goethite
Chemical Engineering Journal, 2013Co-Authors: Xuetao Guo, Qian Zhang, Chen Yang, Zhi Dang, Qingyu MengAbstract:Abstract In order to understand the Sorption processes of tylosin (TYL) and sulfamethazine (SMT) on soils, the Sorption thermodynamics and kinetics properties of two chemicals on goethite were investigated through Sorption equilibrium and Sorption rate experiments. The results showed that the Sorption of TYL and SMT were nonlinear and the Sorption capacities were influenced by the pH conditions of solution. The Sorption rates for TYL and SMT decreased as the initial concentration increased. The Sorption process might be constituted with the initial boundary layer diffusion or external surface, then the intraparticle diffusion or pore diffusion stage and finally equilibrium stage related with the Sorption on the interior surface of sorbent. Thermodynamic calculations of Sorption of TYL and SMT on goethite revealed that the Sorption of TYL on goethite was exothermal and spontaneous and SMT was endothermic and spontaneous. The results indicated that the transportation abilities of TYL and SMT might be weak for the soils rich in iron oxide. The significant differences in the Sorption behavior of two chemicals might be related with their physicochemical properties and suggested that the Sorption mechanisms of TYL and SMT on goethite would be complicated and the domain Sorption mechanism for each chemical at different pH conditions would be variable. It should be noted to assess the environmental risks of TYL and SMT.
