Effective heterogeneous catalysis of micro-size H3PMo6W6O40@rht-MOF-1 for degradation of phenolic compounds under molecular oxygen

Since the huge damage to human health and the survival of animals and plants was caused by phenol and its derivatives, it is impending to develop efficient and durable heterogeneous catalysts of catalytic wet air oxidation (CWAO) for eliminating these phenolic compounds. The heterogeneous system POMs@rht-MOF-1 H3PMo12−xWxO40@rht-MOF-1 (1, x = 3; 2, x = 6; 3, x = 9) and the micro-size complex 2 (denoted by 2 (1 µm) have been designed and synthesized. FT-IR, PXRD, TGA, N2 adsorption-desorption isotherms and XPS were applied to characterize their structures. Upon complex 2 (1 µm) is employed as catalysts for degradation of phenol under molecular oxygen (O2) as oxidant, the catalytic degradation efficiency and TOC reduction up to 95 % and 91 % under optimized condition, respectively. The catalyst 2 (1 µm) could be reused 7 times with negligible reduction. An apparent Arrhenius activation energy of 33.13 KJ/mol and TOF value of 0.3325 (min−1) for phenol were obtained. When catalyst 2 (1 µm) is applied to catalyze mixed phenolic compounds, the degradation efficiency of 85 % is afforded. Furthermore, the catalyzed degradation reaction mechanism is verified via EPR analysis. This method affords an effective path for preparing heterogeneous catalysts and applying in removing the phenolic compounds in industrial wastewater. [Display omitted] •Micro-size H3PMo12−xWxO40 @rht-MOF-1 (1, x = 3; 2, x = 6; 3, x = 9) have been afforded.•Micro-size complex 2 exhibits unexpected catalytic efficiency for degradation of phenol by using O2 as oxidant.•The catalyst 2 could be reused 7 times with negligible activity reduction.•The radical reaction mechanism has been verified by EPR spectra.