超顺磁性氧化石墨烯复合材料固定辣根过氧化物酶催化去除氯酚（英文）  

Enzymatic removal of chlorophenols using horseradish peroxidase immobilized on superparamagnetic Fe_3O_4/graphene oxide nanocomposite

作　　者：常青[1] 江国栋[2] 唐和清[1] 李娜[1] 黄佳[1] 吴来燕[1] 

机构地区：[1]中南民族大学化学与材料科学学院催化材料科学国家民委-教育部共建重点实验室,湖北武汉430074 [2]湖北工业大学化学与化工学院,湖北武汉430068

出　　处：《催化学报》2015年第7期961-968,共8页

基　　金：supported by the National Natural Science Foundation of China(21107143,21207033 and 21307164);the Fundamental Research Funds for the Central Universities,South-Central University for Nationalities(CZY15003)~~

摘　　要：采用超声辅助共沉淀法成功地将磁性Fe3O4纳米颗粒沉积在氧化石墨烯表面,利用透射电镜、磁滞回归曲线和X射线光电子能谱对材料进行了表征.将该材料作为载体固定辣根过氧化物酶,考察了固定化酶催化2-氯酚、4-氯酚和2,4-二氯酚降解反应,研究了溶液p H值、反应温度、反应时间、H2O2和氯酚浓度以及固定化酶用量对酚类物质去除率的影响.基于取代基数量和位置不同,去除率排序为2-氯酚<4-氯酚<2,4-二氯酚.另外,采用GC-MS研究了降解过程中的氧化产物.固定化酶的生化性质研究表明,固定化酶比游离酶具有更好的储存稳定性、pH稳定性和热稳定性.经过4次循环利用,固定化酶仍保留66%的活性,说明磁性纳米材料可以分离回收并重复利用,在污水处理领域具有应用前景.Magnetic Fe3O4 nanoparticles were successfully deposited on graphene oxide sheets by ultra- sound-assisted coprecipitation. The nanoparticles were characterized using transmission electron microscopy, vibrating sample magnetometry, and X-ray photoelectron spectroscopy. The synthesized material was used as a support for the immobilization of horseradish peroxidase （HRP）. The removals of 2-chlorophenol, 4-chlorophenol, and 2,4-dichlorophenol using the immobilized HRP were investigated. Batch degradation studies were used to determine the effects of the initial solu- tion pH values, reaction temperature, reaction time, H202 and chlorophenol concentrations, and immobilized enzyme dosage on the removal of chlorophenols. The different numbers and positions of electron-withdrawing substituents affected the chlorophenol removal efficiency; the order of the removal efficiencies was 2-chlorophenol 〈 4-chlorophenol 〈 2,4-dichlorophenol. The oxidation products formed during chlorophenol degradation were identified using gas chromatography-mass spectrometry. The biochemical properties of the immobilized HRP were investigated; the results indicated that the storage stability and tolerance to changes in pH and temperature of the immobilized HRP were better than those of free HRP. The nanoparticles were recovered using an external magnetic field, and the immobilized HRP retained 66% of its initial activity for the first four cycles, showing that the immobilized HRP had moderate stability. These results suggest that the immobi- lized enzyme has potential application in wastewater treatment.

关 键 词：磁性纳米材料 固定化酶 辣根过氧化物酶 生物降解 氯酚类物质 废水处理 

分 类 号：O629.8[理学—有机化学] X703[理学—化学]