Effect of Tetrabutylammonium on Methylene Blue Adsorption

Abstract

Artificial dyes such as methylene blue are commonly detected in textile industry wastewater. Clay is commonly used as an economical and effective adsorbent for methylene blue in textile waste treatment. The addition of surfactants into the system is usually done to increase the adsorption capacity of the clay. In this study, we used a molecular dynamics simulation method to study the effect of tetrabutylammonium organic surfactant on the adsorption process of methylene blue on the clay surface. The modelled clays are pyrophyllite and montmorillonite which are hydrophobic and negatively charged, respectively. The simulation results show that the addition of tetrabutylammonium surfactant causes a 12 % and 40% decrease in the binding of methylene blue to the surfaces of pyrophyllite and montmorillonite, respectively. This is due to the occurrence of competitive adsorption in both systems. Therefore, the addition of tetrabutylammonium surfactant was considered ineffective in increasing the adsorption capacity of pyrophyllite and montmorillonite.