Expansion graphite (EG) processing of an expanded volume of 400 mL/g was prepared with 50 mesh crude graphite after chemical oxidation intercalation of potassium permanganate and vitriol, and its adsorption kinetics a...Expansion graphite (EG) processing of an expanded volume of 400 mL/g was prepared with 50 mesh crude graphite after chemical oxidation intercalation of potassium permanganate and vitriol, and its adsorption kinetics and thermodynamics characteristics for xylenol orange (XO) was investigated. In thermodynamic study, adsorption isotherm and free energy change (⊿G°) were detected and calculated, respectively. Influence of ionic strength on adsorbance was investigated. Kinetic studies were carried out with a series of XO concentration under different temperatures, and the data were simulated with pseudo first-order and second-order kinetic model, respectively. Results illustrate: adsorption of EG for XO is a spontaneous process, and adsorption isotherm is type II;equilibrium adsorbance increases with the increase of ionic strength. Kinetic studies show that the kinetic data can be delineated by pseudo second-order kinetic model. Initial adsorption rate increases with the increase of temperature. Adsorption activation energy is less than 20 kJ/mol;physical adsorption is the major mode of the overall adsorption process.展开更多
3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMS...3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMSM-NH2 monolithic had a high efficiency value of 99.3% for Cu2+ remediation when the Cu2+ solution was at an initial concentration of 10.32 mg/L. The regeneration study of the WMSM-NH2 monolithic presented that the adsorp- tion efficiency of 89.0% was remained and a mass of 92.0% was left after seven adsorption-desorption cycles were executed. The monolithic material with high resistance to the acid and good mechanical stability can facilitate the operations of adsorption and regeneration of the adsorbent.展开更多
文摘Expansion graphite (EG) processing of an expanded volume of 400 mL/g was prepared with 50 mesh crude graphite after chemical oxidation intercalation of potassium permanganate and vitriol, and its adsorption kinetics and thermodynamics characteristics for xylenol orange (XO) was investigated. In thermodynamic study, adsorption isotherm and free energy change (⊿G°) were detected and calculated, respectively. Influence of ionic strength on adsorbance was investigated. Kinetic studies were carried out with a series of XO concentration under different temperatures, and the data were simulated with pseudo first-order and second-order kinetic model, respectively. Results illustrate: adsorption of EG for XO is a spontaneous process, and adsorption isotherm is type II;equilibrium adsorbance increases with the increase of ionic strength. Kinetic studies show that the kinetic data can be delineated by pseudo second-order kinetic model. Initial adsorption rate increases with the increase of temperature. Adsorption activation energy is less than 20 kJ/mol;physical adsorption is the major mode of the overall adsorption process.
基金Supported by the National Natural Science Foundation of China(Nos. 50573030 and 21171065).
文摘3-Aminopropyltriethoxysilane functionalized worm-like mesoporous silica monolithic(WMSM-NH2) was prepared and used as a new regenerable adsorbent for the removal of Cu2+ ions. The analysis results show that the WMSM-NH2 monolithic had a high efficiency value of 99.3% for Cu2+ remediation when the Cu2+ solution was at an initial concentration of 10.32 mg/L. The regeneration study of the WMSM-NH2 monolithic presented that the adsorp- tion efficiency of 89.0% was remained and a mass of 92.0% was left after seven adsorption-desorption cycles were executed. The monolithic material with high resistance to the acid and good mechanical stability can facilitate the operations of adsorption and regeneration of the adsorbent.