Separation and enrichment of benzene from its aqueous solution by adsorption using hydrophobic mesoporous silica solid adsorbent

Benzene is used most commonly as a solvent for printing paints, dry cleaning etc. It has been identified as one of the volatile organic compounds (VOCs). It is required to remove benzene from its aqueous solution because of its carcinogenic nature and associated health risks.The objective of the present work is to remove benzene from its aqueous solution by adsorption using silylated mesoporous silica and enrich it for later recovery and re-use. To achieve this, we had earlier synthesized and characterized unsilylated and silylated mesoporous silica (MCM~V41) and used it for benzene separation from benzene-water mixture. We found that silylated samples gave a better performance than what is known in the literature. This project will involve synthesis and characterization of both unsilylated and silylated mesoporous silica of two kinds - MCM-41 and SBA-15, so as to carry out equilibrium adsorption studies for benzene removal and their comparison. Bigger pores and larger specific volume of silylated SBA-15 sample is expected to give higher adsorption capacity of benzene because of smaller diffusional resistance to benzene molecules. The experimental data will be validated by developing a model to optimize the performance for such an application.