苯酚属于高毒性有机物,工业废水中常含有苯酚等酚类污染物,即使低浓度排放,对生态环境也会造成极大的危害.本文以聚乙烯醇-壳聚糖复合物为载体包埋微生物,获得了高效降解水中苯酚的固定化微生物球形催化剂.固定化微生物初次处理苯酚水溶液,30℃下反应120 h,苯酚浓度由100 mg·L-1降至0.48 mg·L-1,苯酚降解率高于99％;而在相同条件下,使用游离微生物苯酚的降解率仅为21.1％.固定化微生物重复使用处理苯酚水溶液,催化活性提高显著,第4次重复使用,反应5 h苯酚的降解率已达到99％;65次循环处理苯酚水溶液,苯酚的降解率达到99％所用的时间几乎保持不变(5 h).聚乙烯醇-壳聚糖复合物包埋微生物,既包埋了微生物实现了固定化,又为微生物活性的发挥提供了适宜的微环境,使得制备的固定化微生物具有良好的催化活性和重复使用性.%Phenolic compounds such as phenol and chlorophenol are highly toxic pollutants that often appear in the effluent of vari-ous industrial wastewaters,which cause serious hazard for the ecological environments after discharge into any water body even at relatively low concentrations. The main objective of this research is to obtain the high efficient spherical catalysts of degrading phe-nol by using polyvinyl alcohol-chitosan(PVA-CS)composite for entrapment of microorganism. The 99％of degradation rate for phe-nol was obtained using immobilized microorganism as the initial phenol concentration was reduce from 100 mg·L-1 to 0. 48 mg· L-1 at 30℃ for 120 h,whereas the degradation rate of phenol only was 21. 1％under the same conditions using free microorganism. The catalytic activity of immobilized microorganism during 1～4 treating recycles could be significantly enhanced so that the degra-dation rate of phenol had reached 99％within 5 h in the fourth recycle. The degradation rate of phenol reached 99％in 5 h during 65 recycles. PVA-CS composite embedded microorganism aws not only enclosed to the microorganism to achieve the immobilization,but also provided a suitable microenvironment for the microbial activity,which made the prepared immobilized microorganism had good catalytic activity and reusability.
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