Photocatalytic-proxone process application in the degradation of toluene-diisocyante, and methylene diphenyl diisocyanate from polluted air

[Display omitted] •The nanocomposite was well synthesized based on XRD, FT-IR, FESEM, EDAX, EDS element mapping, TEM, BET, XPS, and UV–vis spectra analysis.•Under optimum conditions, more than 90% of isocyanates were degraded.•The synergistic effect coefficient of the mechanisms was 2.03 and 2.34 for TDI and MDI, respectively.•The process had good stability in the isocyanates removal, and stable performance was observed for six runs.•The ozone concentration residual in the system was reported to be negligible. Isocyanates are one of the most widely used semi-volatile compounds in various industries, including the polyurethane industry. Applying a hybrid advanced oxidation process to the degradation of toluene diisocyanate (TDI) and methylene diphenyl diisocyanate (MDI) from polluted air were the main aims of the study. The BiOI@MOF/Zeolite nanocomposite was prepared by the solvothermal method. XRD, FT-IR, FESEM, EDAX, EDS element mapping, TEM, BET, XPS, and UV–vis spectra analysis were applied to indicate the nanocomposite characters. The effect of flow, ozone concentration, hydrogen peroxide concentration, initial isocyanates concentration, and relative humidity were investigated. The concentration of isocyanates measurement via NIOSH 5522 standard method. In the optimum conditions of the process, the supplementary studies were done. The results of the analysis of composite structure indicated that well synthesized had been done. Experimental results showed optimal operating conditions could degrade more than 90 % of isocyanates. The synergistic effect coefficient of the mechanisms was 2.03 and 2.34 for TDI and MDI, respectively. The stability of the process was observed in 6 consecutive steps. The residual ozone concentration in the system's outlet was negligible (0.047 mg/l). The CO2 and CO emissions proved that the mineralization of isocyanates occurred. The theoretical mineralization rate was 0.64 and 0.55 reported for TDI and MDI, respectively. The simultaneous presence of MDI and TDI in the reactor decreases the efficiency of the process. The pure oxygen gas, pure nitrogen gas, and atmospheric as a carrier gas showed different performances in the process of isocyanate removal (80.8, 35.4, and 61.7 % degradation in the simultaneous presence of MDI and TDI).