Highly efficient activation of peroxymonosulfate by calcinated construction & demolition waste powder with free radical generation for organic pollutant degradation

Background A simple, efficient and cost-efficiency peroxymonosulfate (PMS) oxidation process for organic pollutant removal is expected. This research aims to investigate the feasibility of construction & demolition waste (C&D waste) as recycled material for organic pollutant degradation. Methods C&D waste was novelty introduced into the advanced oxidation process for organic pollutant removal. Taking phenol as the target pollutant, the effects of C&D waste loading, PMS concentration, particle diameter and solution pH were all investigated in this study by a series of batch tests and spectrometry measurements. Significant findings Both the intrinsic oxidation power of PMS and the adsorption of the pretreated C&D waste were negligible under this CDW/PMS system. However, calcinated C&D waste, with calcium silicate generation, enhanced the degradation efficiency of target organic pollutant by promoting the decomposition of PMS to generate • OH and SO 4 •− . Both • OH and SO 4 •− had been detected through the free radicals quenching tests and electron paramagnetic resonance (EPR) spectrometry. Except for high temperature pretreatment, the micro C&D waste after mechanical treatment could also improve the organic pollutant degradation efficiency with a high kinetic rate as a bonus especially for the introduced powder at low doses.