Abstract
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 ~1O2, and minor roles of SO4~(·-) and ·OH 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 ~1O2 generation. Notably, the double vacancy defect was also a preferential site for ~1O2 production. This study advances mechanistic understanding of collaborative contribution of active sites to PMS activation.
NSTL