| The properties and applications of organobentonites in environmental protection were described. The adsorption of metal ions from water by organobentonites was reviewed. The application of organobentonites in wastewater treatment and remediation of polluted environment were also forecasted.Novel modified bentonites were prepared by liquid-phase reaction by using cationic surfactant and cationic-anionic surfactants as ion exchanger. The conditions of ion adsorption were investigated. The results show that bentonite and organobentonites have great ion-adsorption capacities at pH=2 and pH=5.5-6 respectively. The reaction kinetics of organobentonite for the removal of metal ions from solution has been investigated. Different kinetic equations were used to fit the dynamic process of different ion adsorption. The parameters, i.e. adsorption activation energy, activation entropy, activation enthalpy and activation free energy were calculated by relative kinetic equation.Investigation was conducted to evaluate the competitive adsorption of Cu2+ Pb2+ and Cr(VI) . Results show that the competitive adsorption of Cu2+ and Cr(VI) is complicated, but the competitive adsorption of Cu2+ and Pb2+ is relatively simple. When Cu2+ and Pb2+ coexisted with low concentration, the competition is not obvious at entire range of pH. The competition is remarkable under high concentration at pH＜6.According to all experiment dates and analysis of theory, the modified bentonites play a great role on the wastewater treatment and environment remediation. In a word, the modified bentonites has extensive prospect on the treatment of contaminate environment. |
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