Oxidation of Sulfamethoxazole by Rice Husk Biochar-Activated Persulfate

In the present study, biochars from rice husk were synthesized via pyrolysis at 400, 550, 700 and 850 °C for 1 h under a limited O2 atmosphere, characterized with various techniques of used as catalysts to activate persulfate degrade sulfamethoxazole (SMX). After physicochemical characterization biochars. SMX degradation tests performed using different water matrices, biochar concentrations initial pH solutions. Also, spiked solutions bicarbonate, chloride, calcium nitrate, humic acid or alcohols tested. It was found that catalytic reactivity rises temperature. Biochar is crucial oxidation it can be described pseudo first–order kinetic model. Real matrices hinder process, in waste removal 41% 90 min, comparable inhibition obtained bicarbonates solution (52% within min) while complete achieved ultrapure matrices. The presence alcohol slightly inhibits contrary addition sodium azide which causes significant inhibition, this an evidence either electron transfer/singlet oxygen control dominated by surface-bound radicals.