Fabrication of CeO2/municipal sludge-based biochar composites with outstanding photocatalytic degradation properties

CeO2/sludge-based biochar composites were prepared by a combination of carbonization and oxidation and applied to photocatalytic degradation of humic acid reactions. The effects of the preparation process sequence on the products were investigated from the perspectives of microscopic morphology and phase composition. The results showed that when the carbonization temperature was selected as 700 degrees C and the oxidation temperature was selected as 650 degrees C, accompanied by a certain holding time, structurally stable composites were obtained. In the composites, the biochar increased the adsorption property of the system, as well as facilitated the improvement of CeO2 photocatalytic activity. The adsorption degradation rates of SICO and SCIO on humic acid after 3 h of illumination were 57.92% and 82.88%, respectively, which were much better than those of pristine CeO2 and pure sludge-based biochar. This study provided new path for the practical application of municipal sludge disposal products.