Catalytic Ozonation of Recalcitrant Organic Chemicals in Water Using Vanadium Oxides Loaded ZSM-5 Zeolites

Abstract

The discharge of wastewater having recalcitrant chemical compositions can have significant and adverse environmental effects. The present study investigates the application of a catalytic ozonation treatment for the removal of recalcitrant organic chemicals (ROCs) from the water. Novel catalytic materials using vanadium (V) oxides deposited onto the surface of NaZSM-5 zeolites (V/ZSM) were found to be highly efficient for this purpose. The highly-dispersed V oxides (V 4+ and V 5+ ) and Si-OH-Al framework structures were determined to promote the surface reaction and generation of hydroxyl radicals. The constructed V1/ZSM 450 (0.7 wt% of V loading and 450°C of calcination) exhibited the highest activity among the developed catalyst compositions. The V1/ZSM 450 -COP increased the mineralization rate of nitrobenzene and benzoic acid by 50 and 41% in comparison to single ozonation. This study demonstrates the enhanced potential of V/ZSM catalysts used with catalytic ozonation process (COP) for the treatment of chemical wastewaters.

Recent Progress and Prospects in Catalytic Water Treatment

“…Also, a wide range of zeolites, alone or modified by addition of metal oxides have been found to be efficient for pollutant removal by catalytic ozonation, due to a combination of parameters, including their high surface area, the possibility of adjusting hydrophilicity/hydrophobicity, the acidity by the silica to alumina ratio and the pore size. Metals, in the metallic state, supported on metal oxides are also active catalysts for ozonation by either favoring the production of •OH and/or the adsorption of the organic pollutant 32 . Some examples of the reaction mechanisms will be detailed in paragraph 2.2.…”

“…Metals, in the metallic state, supported on metal oxides are also active catalysts for ozonation by either favoring the production of • OH or the adsorption of the organic pollutant. 32 Some examples of the reaction mechanisms will be detailed in section 2.2. Basically there are three types of mechanisms to explain the interaction of the catalyst with organic pollutants and O 3 :…”

Comparative study on heterogeneous and homogeneous catalytic ozonation efficiency in micropollutants' removal

“…The evaluation of adsorption capacity, regarding a solid catalyst, is considered as very important in the catalytic ozonation process, due to the following reasons: (1) research studies have shown that heterogeneous catalytic ozonation is a synergistic process, during which, adsorption may also contribute via the improved contact between the pollutant and the catalyst (Valdés et al 2012;Shahamat et al 2014), and (2) a solid material can be characterized as catalyst when the efficiency of the catalytic system is higher than the efficiencies' sum of adsorption and of single ozonation (Xu et al 2019); i.e., the solid material should act mainly as a catalyst and not as an adsorbent agent. Table 2 shows the adsorption capacity of calcite against benzotriazole, carbamazepine, and p-CBA.…”

Advanced Oxidation Process for Degradation of Carbamazepine from Aqueous Solution: Influence of Metal Modified Microporous, Mesoporous Catalysts on the Ozonation Process

“…Zeolite catalysts exhibited an improvement in the ozonation of the pharmaceutical compound paracetamol [30] and ibuprofen [31]. Moreover, loading of the metals on zeolite catalysts increases the catalytic ozonation efficiency [32].…”