| Mg/Al Layered Double Hydroxides(LDHs) is an inorganic magnesium material with special double-layer structure and anionic exchange capability. On account of the special structure and capability, Layered Double Hydroxides have been widely used in the domain of catalysis, medicine, water treatment et al. Recently, with people's deeply studying on the structure and character of Layered Double Hydroxides, their applying domain also extend. Inexpensive Mg/Al Layered Double Hydroxides are made by perfect mixed spraying reactor at hydrothermal condition for the first time and the stuff are industrial cheap magnesium sulfate, aluminum sulfate, sodium hydroxide, sodium carbonate. After analysis by XRD and IR, it is found that the Mg/Al Layered Double Hydroxides product's crystal structure,purity and character are good. It has been proved that the removing effect of the LDHs and its calcined products for inorganic Anion is good.The waste water containing sulfur has badly polluted the environment, and has deeply endangered the surrounding organism's life, especially thiocyanate and Sulphide waste water. It is urgent to find a efficient way to remove them from the surrounding. In this paper, the performances of adsorption of Calcined Mg/Al Layered double Hydroxides(CLDH) for thiocyanate and Sulphide are studied. The effect factors of calcined temperature of Mg/Al Layered double Hydroxides and sorbent dosage, adsorption temperature, adsorption time, initial concentration, pH value were investigated by static adsorption experiment. The purpose of this research is to find the optimum condition of removing the pollutants. The adsorption mechanism has been studied by contrasting analysis of X-ray diffract grams of Calcined Mg/Al Layered double Hydroxides before and after the adsorption experiment.The adsorption of CLDH which was Calcined at 500℃(CLDH-5) for thiocyanate ion is best of all the Calcined products. When initial concentration of thiocyanate is 25mg/L in the solution, the economical and rational dosage of CLDH-5 is 4mg/L and the adsorption could reach Equilibrium after 4 hours'adsorption time. Maximum adsorption capacity of thiocyanate ion is 104.17mg/g at 40℃when pH value is between 6 and 8. Equilibrium data were fitted very well to the Langmuir mode in the entire saturation concentration range, indicating that the adsorption is of monomolecular layer adsorption. The studies of thermodynamics show that the adsorption enthalpy is 94.30KJ/mo(l>40KJ/mol), the adsorption of thiocyanate ion is the endothermic and chemical adsorption process, and occurs automatically. The studies of kinetics show that the experimental data are fitted well to the first-order kinetic equation, indicating that the adsorption process follow the first-order kinetic mode.The adsorption of CLDH which was Calcined at 400℃(CLDH-4) for Sulphide is best of all the calcined products. When initial concentration of Sulphide is 50mg/L in the solution, the economical and rational dosage of CLDH-4 is 2mg/L and the adsorption could reach Equilibrium after 2 hours'adsorption time. It is disadvantageous to do the adsorption in low temperature, it is better to do the adsorption experiment in normal or high adsorption temperature. Equilibrium data were fitted very well to the Langmuir mode in the entire saturation concentration range, indicating that the adsorption is of monomolecular layer adsorption.. The studies of thermodynamics show that the adsorption enthalpy is 138.98KJ/mol(>40KJ/mol), the adsorption of Sulphide is the endothermic and chemical adsorption process, and occurs automatically. The studies of kinetics showed that the experimental data were fitted well to the first-order kinetic equation, indicating that the adsorption process follow the first-order kinetic mode.The adsorption capability of Calcined Mg/Al Layered double Hydroxides for thiocyanate ion and Sulphide is good, and the CLDH with high adsorption capacity is a low price and non-polluted water treatment sorbent. If its adsorption performance are continually studied on and apply it to water treatment field, it will be very helpful for environment and organism's life, and of theoretical and practical significance.
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