As battery usage increases every year, the number of spent batteries is also increasing, resulting in an important environmental issue. To examine the possibility of using the black mass (BM) obtained from spent batteries as a catalyst material for volatile organic compound (VOC) oxidation, the effect of the pretreating BM on its catalytic activity was investigated. Catalysts were prepared by pretreating the BM in three ways using water and sulfuric acid, and the catalytic performance of each catalyst was compared. The order of activity according to the pretreatment method was water and sulfuric acid hybrid pretreatment (WSBM)>sulfuric acid pretreatment (SBM)>water pretreatment (WBM)>raw (BM). The high adsorption energy site had a great influence on the activity of the catalyst. The number of acid sites and the easily movable lattice oxygen played an important role in the complete oxidation of benzene, toluene and o-xylene. At a gas hourly space velocity of 50,000 h-1, benzene, toluene, and o-xylene were removed completely on the WSBM catalyst at 370 °C, 360 °C, and 350 °C, respectively.