Hydroxylamine facilitated catalytic degradation of methylene blue in a Fenton-like system for heat-treatment modified drinking water treatment residues

Abstract

Rational treatment of drinking water treatment residues (WTR) has become an environmental and social issue due to the risk of secondary contamination. WTR was commonly used to prepare adsorbents due to its clay-like pore structure, but further treatment is subsequently required. In this study, a Fenton-like system of H-WTR/HA/H 2 O 2 was constructed for degrading organic pollutants in water. Speci cally, in this study, WTR was modi ed by heat treatment to increase its adsorption active site, and accelerated Fe(III)/Fe(II) cycling on the catalyst surface by the addition of hydroxylamine (HA). Moreover, the effects of pH, HA and H 2 O 2 dosage on the degradation were discussed using methylene blue (MB) as the target pollutant. The mechanism of the action of HA was analyzed and the reactive oxygen species in the reaction system was determined. Combined with the reusability and stability experiments, the removal e ciency of MB remained 65.36% after 5 cycles, and this study may provide new insights into the resource utilization of WTR.Highlights WTR was employed as potential iron source and catalyst for Fenton-like system.Hydroxylamine promoted Fe (III)/Fe(II) cycling on the H-WTR surface •OH was the main reactive oxygen species in the H-WTR/HA/H 2 O 2 system