Klebsiella PneumoniaeECU-15生物纳米钯催化剂的制备、表征及其合成机理初探  

Preparation, Characterization and Synthesis Mechanism of Biopalladium Nanoparticles Produced by Klebsiella Pneumoniae ECU-15

作　　者：雷彬[1] 张旭[1] 谭文松[1] 朱明龙[1] 

机构地区：[1]华东理工大学生物反应器国家重点实验室,上海200237

出　　处：《高校化学工程学报》2015年第4期873-880,共8页Journal of Chemical Engineering of Chinese Universities

基　　金：国家高技术研究发展计划(2012AA061503)

摘　　要：利用自行筛选的克雷伯氏杆菌ECU-15(Klebsiella pneumoniae ECU-15)还原钯离子制备了生物纳米钯催化剂,并通过TEM、XRD、EDS对纳米钯的结构进行表征。EDS与TEM结果显示:纳米钯颗粒呈球形负载于菌体表面,平均粒径为15 nm。0.5 mg 5%Pd/Pd(0)对Cr(VI)(384μmol?L-1)还原为Cr(III)的转化率在50 min内达到99.67%。在此基础上,进一步利用FTIR与氨基聚苯乙烯微球模拟实验推测K.pneumoniae ECU-15合成生物纳米钯的可能机理是:微生物细胞表面氢酶在生物纳米钯合成过程中调控Pd(0)晶体的活性位点,而表面氨基基团可能仅作为提供成核位点。该研究结果可以为制备高效稳定的生物纳米钯催化剂提供了初步的理论基础和实践指导价值。Palladium（Pd（0）） nanoparticles were prepared by Klebsiella pneumonia ECU-15 and their structural characteristics were analyzed with transmission electron microscopy（TEM）, X-ray diffraction（XRD） and energy dispersive spectrometer（EDS）. TEM and EDS results indicate that the sphere-nano-palladium particles formed have an average size of 15 nm, which are mainly attached on cell surface. More than 99.67% of Cr（VI） （384 μmol·L^-1） was reduced to Cr（Ⅲ） within 50 min using 0.5 mg 5% Pd/Pd（0）. Fourier infrared spectroscopy（FTIR） and stimulated polystyrene microsphere analysis show that the hydrogenase on K. pneumoniae ECU-15 played a critical role on the regulation of Pd（0） active crystal sites, while the amino groups on the surface may only act as nucleation sites. These results provide preliminary support and practical guidance for preparing highly efficient and stable Pd（0） catalysts.

关 键 词：纳米钯 生物催化剂 Pd^2+ 还原 CR(VI)还原 

分 类 号：X781.1[环境科学与工程—环境工程]