Novel peroxymonosulfate activation system based on catalyst prepared from solid waste

Abstract

The recycling of solid waste is of increasing economic and environmental significance. Herein, a low-cost and environmentally friendly catalyst was prepared by simple pyrolysis using warm paste residue as raw material and urea as nitrogen source. The prepared WPR-N-700 catalyst exhibited high catalytic activity for the degradation of bisphenol A (BPA) by activation of peroxymonosulfate (PMS). The removal of 99% BPA in 20 mg L−1 solution was achieved within 30 min in WPR-N-700/PMS system by adding 0.3 g L−1 catalyst and 0.2 g L−1 PMS. The systematic experiments showed that the catalyst exhibited good catalytic versatility and adaptability in many types of refractory organic pollutants and coexisting inorganic ionic systems. The catalyst still had good magnetic properties and could be easily separated under the external magnetic field. The free radical quenching test and electron paramagnetic resonance (EPR) test revealed that sulfate radical (SO4•−), radicals (•OH), superoxide radical (O2•−) and singlet oxygen (1O2) were the primary reactive oxygen species for the degradation of BPA in the WPR-N-700/PMS system. Thus, this study provides an economical and effective method for the recycling of solid waste, and innovatively proposes a new idea of using solid waste to prepare catalysts.