Adsorption and photocatalytic activity of biochar with graphitic carbon nitride (g-C₃N₄)

Biochar has attracted significant attention for its potential as a carbon-neutral biowaste treatment and adsorbent. However, the adsorbed contaminants should be treated further. This study is intended to degrade or mineralize adsorbed contaminants using biochar. Among biowaste, nitrogen rich materials can produce graphitic carbon nitride (g-C₃N₄) with photocatalytic activity through pyrolysis. In this study, urea, glycine, L(+)-arginine, and puree were used to prepare photocatalytic biochars. XRD analysis and screening tests were performed to evaluate the production of g-C₃N₄. As model compounds, Orange G (OG) and Cr(VI) were oxidized and simultaneously reduced in a reactor by biochar. Additionally, biochar effectively activated persulfate to sulfate radicals. The oxidation rate of OG was enhanced by the addition of persulfate, where synergistic effects were observed. Therefore, photocatalytic biochar could be an alternative for treating environmental pollutants.