The catalytic combustion process of air-mixtures containing volatile organic compounds (VOCs) associated with an ionization/ozonization reactor (IOCC technique, ionization–ozonization–catalytic-combustion) has been utilized for the abatement of two very toxic industrial VOCs: acrylonitrile (ACN) and vinyl chloride (VCM). The pre-catalytic effects (electric discharge plus the action of ozone), the conventional and IOCC combustion tests were studied. Two different catalysts were used: oxide catalyst, copper–chromite (Cu–Cr), and Pt metal catalyst (0.5 wt.% Pt/γ-Al 2O 3). The abatement of ACN was markedly influenced by the pre-catalytic effects. Starting from 3 kV, an increasing abatement of ACN was observed with the voltage applied to the ionization reactor at any initial ACN concentration (500–1500 ppm). The ACN catalytic combustion, performed by the IOCC technique, led to 91 and 98% yield of CO 2 on Cu–Cr and Pt catalysts, respectively, at 260°C. Complete absence of hazardous intermediates, such as hydrogen cyanide, was observed. The Cu–Cr catalyst, at 300°C, was able to abate 57 and 23% of VCM at 10 000 and 20 000 h −1, respectively. IOCC combustion led to improved conversion. At 200°C and 3300 h −1, 98% and only 49% of VCM abatement operating according to IOCC and classical combustion was obtained, respectively. The IOCC combustion runs, performed at different initial VCM concentrations (585 and 1170 ppm), indicated a superior abatement when low VCM concentration was fed, at a given catalyst temperature and contact time. This indicated a marked influence of the pre-catalytic effects on the abatement.