In this study, the effect of chemical surface characteristics of natural and Cu-modified zeolite in the adsorption of chlorinated volatile organic compounds (VOCCls) was investigated using infrared spectroscopy. A natural zeolite mainly composed of clinoptilolite and mordenite was used as a parent material. A succession of chemical and thermal treatments produced a Cu-modified natural zeolite (NZ-Cu) with higher adsorption properties toward the elimination of VOCCls. The adsorption of VOCCls onto NZ-Cu zeolite could be explained by a surface mechanism that comprises the interaction not only with Brønsted acid sites present on the original natural zeolite framework; but also with new Brønsted acid sites formed after the successive treatments.