Abstract

Titanium dioxide modified with biochar (Ti-C) was prepared by a sol-gel method for the degradation of humic acid (HA) in aqueous solutions. Under identical conditions, Ti-C contained less TiO2 and showed better HA degradation capacity than that of pure TiO2, and had ca. 20% higher HA removal rate than that of simple Ti-C adsorption. Photocatalytic degradation of HA with Ti-C had an efficient removal rate of 50% at pH = 3, which was ca. 28% higher than that at pH = 7 (HA = 10 mg L-1), while a higher reaction temperature, longer lighting time and larger Ti-C dosage were conducive to HA photocatalytic degradation. SEM micrographs showed that Ti-C had a much rougher surface than the original biochar, and EDS results of Ti-C indicated that its carbon content increased up to 26.2% after biochar doping. Ti-C had an evident anatase structure and a typical SiO2 structure, as revealed by XRD analysis. TOC and GC-MS analysis indicated that HA was effectively degraded and transformed into harmless carbon dioxide. Superoxide radicals were the main active radicals produced for the efficient degradation of humic acid, while hydroxyl radicals and electron-holes also contributed to HA decomposition in Ti-C systems. This work is expected to be helpful for the innovative preparation of titanium dioxide as a low-cost photocatalyst for the degradation of humic acid in water.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.