Performance and characteristics of natural zeolite-based ozone catalysts prepared by the mixing method

The high production cost of ozone catalysts has now become one of the important factors limiting the engineering application of ozone catalytic oxidation technology. The catalyst was prepared by mixing method using cheap and easily available natural zeolite powder as the raw material of catalyst carrier and Cu as the active component. Its performance was measured to investigate the optimal conditions for preparing natural zeolite-based ozone catalysts, and the catalysts were characterized in terms of morphology and structure. The results showed that the natural zeolite-based ozone catalysts prepared by using quick release powder as binder, adding 10% (mass fraction) and roasting at 600 ℃ had the best overall performance, and the adsorption and removal rate of COD from petrochemical wastewater was 37.27% when the reaction was for 30 min. The ozone catalytic oxidation of petrochemical wastewater was carried out by using adsorption-saturated catalysts, the removal rate of COD was 43.48% when the reaction was for 30 min, and the removal rates of fluorescent substances in the three-dimensional fluorescence spectra from region Ⅰ to Ⅴ reached 76.68%, 82.52%, 86.83%, 80.16% and 79.38%, respectively. The characterization results showed that the best natural zeolite-based ozone catalyst had little difference in morphology and structure with the zeolite itself, and the specific surface area only increased by 1.75%. However, the pore volume and the average pore size increased by 23.40% and 21.48%, respectively, compared with that of the natural zeolite, which was conducive to the enhancement of the pollutant adsorption and ozone catalytic oxidation and removal effect. The SEM-EDS results showed that the active component of the catalyst, Cu, was uniformly loaded in the zeolite carriers, which not only improved the catalytic activity, but also helped maintain the stability of the catalyst. In terms of production cost, the zeolite catalyst was 3 000 yuan/t lower than the alumina catalyst, with significant economic benefits. The results show that the natural zeolite-based ozone catalysts prepared by the hybrid method have excellent catalytic activity, are capable of efficiently treating petrochemical secondary effluent, and can significantly reduce the production cost of the catalysts, which has certain potentials in the preparation of catalysts, the deep treatment of industrial wastewater, and the engineering promotion.