Photocatalytic degradation kinetics and mechanism of phenobarbital in TiO2 aqueous solution |
| |
Authors: | Hua Cao Xiulian Lin Haiying Zhan Hong Zhang Jingxin Lin |
| |
Affiliation: | School of Chemistry and Chemical Engineering, Guangdong Pharmaceutical University, Guangzhou 510006, PR China |
| |
Abstract: | 5-Ethyl-5-phenylpyrimidine-2,4,6(1H, 3H, 5H)-trione is an anti-convulsant used to treat disorders of movement, e.g. tremors. This work deals with the transformation of phenobarbital by UV/TiO2 heterogeneous photocatalysis, to assess the decomposition of the pharmaceutical compound, to identify intermediates, as well as to elucidate some mechanistic details of the degradation. The photocatalytic removal efficiency of 100 μm phenobarbital is about 80% within 60 min, while the degradation efficiency of phenobarbital was better in alkaline solution. The study on contribution of reactive oxidative species (ROSs) has shown that OH is responsible for the major degradation of phenobarbital, while the photohole, photoelectrons and the other ROSs have the minor contribution to the degradation. Finally, based on the identification of degradation intermediates, two main photocatalytic degradation pathways have been tentatively proposed, including the hydroxylation and cleavage of pyrimidine ring in the phenobarbital molecule respectively. Certainly, the phenobarbital can be mineralized when the photocatalytic reaction time prolongs. |
| |
Keywords: | |
本文献已被 ScienceDirect 等数据库收录! |
|