Property and mechanism of phenol degradation by biochar activated persulfate

Abstract

In this study, corn stover was used to prepare biological activated carbon (BAC). First, the calcination temperature of BAC was optimized, and the calcination rate of BAC as the activator was confirmed to be maximal when the heating rate was 5.0 °C min−1, the sample was allowed by cool naturally, and the calcination temperature was maintained at 900.0 °C for 180 min. The oxidants persulfate (PDS) and hydrogen peroxide were compared. In the case of a certain amount of BAC, the PDS was an effective as an oxidant and the dosage was small. The preferred oxidant was thus determined to be PDS. Under the PDS/BAC system, the PDS dosage (PDS/phenol molar ratio of 5:1), the initial pH value of the system (6.45), the temperature of the system (20.0 °C), and the initial concentration of phenol were optimized. The effect of BAC was explained. At the end of the experiment, the stability of BAC was verified. The degradation rate of phenol by BAC after four repetitions could still reach 80.50 % (the initial concentration of phenol was 50.00 mg L−1), and the degradation effect of the total organic carbon (TOC) of the system within 300 min was verified. The degradation rate of TOC was 85.94 %, and the effect was ideal. The results of a simple preliminary analysis of the degradation mechanism are presented. Keywords: Biochar, Persulfate, Carbon activation, Phenol