2,4,6-Trinitrotoluene (TNT), 2,4-Dinitrophenol (DNP) and 2,4-Dichlorophenoxylacetic acid (2,4-D) present in wastewater are toxic organic compounds that must be removed. This paper described the mineralization of these compounds in the presence of atmospheric oxygen activated with ZVI-EDTA. The experimental data has shown that oxygen activated with ZVI-EDTA lowers the concentrations of organic compounds and the chemical oxygen demand (COD) with respect to reaction time. The focus of the study was the influence of ZVI-mass and pH on the mineralization efficiency of organic compounds.