Adsorption Properties of the Macro/Nano-Clay in Crystal Violet Solution

Abstract

In this study, different appearances, structures and morphologies of macro-clay G105-Polymer grade montmorillonite (PMMT) and nanoclay Lithium magnesium silicate (LMSH) were compared and analyzed, which were used in different conditions of non-adsorption and adsorption of crystal violent (CV). Adsorption kinetics and properties of the macro/nanoclay in CV solution were studied, and adsorption time, dye concentration and environmental pH were the main factors on the inspection in this work. The adsorption mechanisms of the macro-/nanoclay on CV were investigated. The results showed that adsorption actions of PMMT and LMSH on CV were some similar, such as time-dependent, linear growth of adsorbed CV amount with increasing CV concentration, adsorption capacity of macro-/nanoclay declined firstly and then increased in 10mg/L CV solution along with increasing pH value. But the adsorption differences in two systems of PMMT-CV and LMSH-CV were obvious. Adsorption behavior of LMSH-CV system showed two adsorption phenomena. Under neutral conditions, adsorbed CV amount in 0.5g LMSH was 1.69 times that of PMMT. Adsorption amount of LMSH was more significant to be affected by dye concentration and pH conditions. The research achievements further showed that adsorption mechanism was the root cause of the following difference. The adsorption of PMMT-CV relied mainly on iron-exchange effect of layers replaceable cations and surface adsorbed ions with CV cations, while the significant adsorption of LMSH-CV was mainly due to the electrostatic interaction from layers negative charge distribution and CV cationic properties in the solution, partly surface ions exchanges also existed in the adsorption process of LMSH-CV.