Adsorption of Crystal violet in Aqueous Solution by Natural Peat

The adsorption of crystal violet(CV)in aqueous solutions by natural peat(NP)was investigated through batch experiments,including the affecting factors,kinetics,isotherms and thermodynamics of the adsorption.The adsorption capacity of NP forwards CV adsorption was 31.77~70.49 mg·g-1 after 90 min under the experiment conditions,and this capacity was increased with the increasing initial CV concentration or temperature,but decreased with the increasing amounts of NP.Also,increasing pH would enhance the adsorption capacity when pH was between 5 and 8.The adsorption process approximately reached equilibrium in 60 min,and the adsorption kinetics followed pseudo-second order reaction models.Besides,the adsorption isotherms in different temperature were in accordance with the Langmuir equation and thermodynamics evaluation showed that the adsorption process was endothermic.The enthalpy changes(ΔH)and the entropy changes(ΔS)were positive,while the free energy changes(ΔG)were negative.