To utilize for Chlorinated Volatile Organic Compounds (CVOCs) adsorption, RH-MCM-41 showed higher adsorption capacity than commercial sorbents including mordenite and activated carbons. However, the adsorption of CVOCs was found to be competitive between CVOCs and water itself. To enhance the adsorption capability of RH-MCM-41 for CVOCs, it needed to be modified in order to increase its hydrophobicity.