Influence of salinity on the heterogeneous catalytic ozonation process: Implications to treatment of high salinity wastewater

Coal chemical industry membrane concentrates: characterisation and treatment by ozonation and catalytic ozonation processes

“…The high concentration of Cl − (~200 mM) may potentially create challenges in application of ozonation and catalytic ozonation processes. As shown in our recent work (Yuan et al 2022), scavenging of ˙OH by chloride ions (particularly in the case of the catalytic ozonation process) as well as transformation of humic-like moieties to a more compact hydrophobic form in the presence of cations (such as Na + /Ca 2+ ) affects the removal of organics by both pure ozonation and catalytic ozonation processes. Since the presence of divalent cations results in more charge shielding between adjacent functional groups in humic compounds compared to that induced by monovalent ions (Baalousha et al 2006), we Fe is present as Fe III (most likely as Fe III organic complexes).…”

“…Upon receipt, the catalyst was prewashed with MQ water until the supernatant was clear and then dried at 60°C prior to use. Detailed characterisation of the surface properties and composition of the catalyst was performed in our earlier work (Yuan et al 2022) and showed that the major constituents of the catalyst were hematite (01-084-9870), Al 2 O 3 (00-046-1131) and MnO 2 (04-009-8106).…”

“…Thus, we investigated the degradation of CCI concentrate by catalytic ozonation employing an Fe-oxide@Al 2 O 3 catalyst. In our earlier work (Yuan et al 2022), we investigated the mechanism of the catalytic ozonation process using Fe-oxide@ Al 2 O 3 and showed that O 3 decays on the Fe-oxide@Al 2 O 3 surface to form surface-located ȮH which then diffuse away from the surface and interact with organic compounds present in the interfacial boundary layer and/or bulk solution. The formation of surface-located ȮH on catalyst-O 3 interaction was confirmed in our earlier work (Yuan et al 2022) using fluorescence microscopy imaging analysis.…”

“…Similar to the cases of C1# and C2#, Cl − and SO 4 2− are the dominant anions in the CW1# sample as well. The high concentration of Cl − (~50 mM) and high hardness of these samples may potentially create challenges in the application of ozonation and catalytic ozonation processes (Yuan et al 2022). Since the impact of Ca 2+ on the transformation of humic substances and the strength of aggregates formed is more pronounced compared to that observed in the presence of Mg 2+ (Hakim et al 2019), the degradability of humic-like moieties is expected to be lower for this concentrate sample compared to C1# and C2#.…”

Removal of Paracetamol from Aqueous Solutions by Photocatalytic Ozonation over TiO2-MexOy Thin Films

“…In order to fulfill this difficult task, it is necessary to use a versatile and efficient water treatment method, with large applicability in terms of aqueous effluents flow rate, source type, and the removal of target pollutants at the level requested by environmental regulation (which are subject to change toward lower values in a rapid pace). Catalytic ozonation is a technique with a significant capacity to accomplish these requirements in every respect due to the capability to oxidize/mineralize almost every organic pollutant [11][12][13][14][15][16][17][18][19][20][21]. Moreover, this method is a prominent example of advanced oxidation processes-a well-known category of water treatment approaches centered on using OH• radicals.…”