Due to the carcinogenicity, toxicity and persistence, chlorophenols are listed among top priority control pollutants by the US EPA and the EU. People are seeking more efficient process for degradation of chlorophenols, particular with high concentration.

Researcher from Institute of Process Engineering, Chinese Academy of Sciences (IPE-CAS) proposed a newsimultaneous photocatalytic-enzymatic process for degradation of 2,4-chlorophenol (2,4-DCP) with TiO2/UV and immobilized laccase.

With the simultaneous photocatalytic-enzymatic process, degradation efficiency of 2,4-DCP was significantly increasedas compared with the results obtained when immobilized laccase or TiO2/UV were separately used. 

Moreover, the results showed that the increase of degradation efficiency was more remarkable for the degradation of 2,4-DCP with high concentration. When the concentration of 2,4-DCP was 5mM, the removal of 2,4-DCP was 90% within 2h with the coupled degradation process. The degradation kinetics were analyzed, using an intermediate model, as intermediates were formed during the degradation process.

Furthermore, a thermometric biosensor using the immobilized laccase as biorecognition element was constructed for monitoring the degradation of 2,4-DCP, the result indicated that the biosensor was precise and sensitive. The results presented in this work will provide a novel strategy for the degradation of concentrated 2,4-DCP and a new method for on-line monitoring of chlorophenol. 

The project is supported by grants from National Natural Science Foundation of China (20976180), and Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (No.2006-331), has been published on the Journal of Hazardous Materials (2012, 205-206：150-155).

AUTHOR CONTACT: Zhang Songping 

Institute of Process Engineering, Chinese Academy of Sciences. Beijing, China,

E-mail: spzhang@home.ipe.ac.cn