Sulfamethoxazole degradation by regulating active sites on distilled spirits lees-derived biochar in a continuous flow fixed bed peroxymonosulfate reactor

Defect type and interactions among active sites are critical in heterogeneous peroxymonosulfate (PMS) system. Herein, a continuous flow fixed bed PMS reactor with distilled spirits lees derived biochar (DSLBs)/quartz wool was designed to explore the synergistic roles of active sites. Satisfyingly, with high graphite N, C-O content and defect degree, DSLB-800 exhibited superior catalytic activity, durability and applicability for sulfamethoxazole (SMX) removal. The dominant contribution of O-1(2), and minor roles of SO(4)(center dot-& nbsp;)and (OH)-O-center dot were confirmed. Single graphite N, C-O and C-O, combined interactions between graphite N and pyridine N, graphite N and pyrrole N, pyridine N and pyrrole N, C-O and O-C-O, O-C-O and C-O, as well as interactions among graphite N, pyridine N and pyrrole N contributed to O-1(2) generation. Notably, the double vacancy defect was also a preferential site for O-1(2) production. This study advances mechanistic understanding of collaborative contribution of active sites to PMS activation.