Catalytic activity of biomass-supported Pd nanoparticles: Influence of the biological component in catalytic efficacy and potential application in 'green' synthesis of fine chemicals and pharmaceuticals
Catalytic activity of biomass-supported Pd nanoparticles: Influence of the biological component in catalytic efficacy and potential application in 'green' synthesis of fine chemicals and pharmaceuticals
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DOI：
10.1016/j.apcatb.2013.09.045
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发表时间：
2014-04-05
影响因子：
22.1
通讯作者：
Macaskie, L. E.
中科院分区：
文献类型：
--
作者：
Depanche, K.;Bennett, J. A.;Macaskie, L. E.
5个革兰氏阴性和2个革兰氏阳性细菌菌株以其对重金属的耐受性或还原金属离子的能力而闻名，在初始摄取PdCl42-后，通过在H-2下还原可溶的Pd(II)离子，将Pd(0)纳米颗粒(NPs)包覆一层，而不添加电子供体(生物吸附)，其中革兰氏阴性菌株对Pd(II)的吸收能力类似于5倍。铜绿假单胞菌异常地积累了Pd(II)；不排除通过内源电子供体还原为Pd(0)的可能性。随后H-2介导的Pd(II)还原的初始速率与生物吸附过程中去除的Pd(II)相关(r(2)=0.9)。TEM显示Pd-NPs的菌株特异性变异。在1：3的Pd：生物质负荷下，大肠杆菌和脱硫弧菌的细胞表面呈现均匀的小颗粒覆盖，其他菌株表现出较大的聚集体。革兰氏阳性细胞所产生的NPs明显大于革兰氏阴性细胞。在负载量为1：19的条件下，所有催化剂均为铬(VI)还原和两个Heck偶联反应的活性催化剂。BioPd(大肠杆菌)、BioPd(脱硫杆菌)和BioPd(氧化乳杆菌)分别是最好和最差的催化剂。在Fleck和Suzuki偶联反应中，根据工业协议，BioPd(E.culi)被进一步测试为过程催化剂。实验室和工业试验(苯基碘化物和丙烯酸乙酯的偶联)使肉桂酸乙酯的转化率分别为75%和78%。该生物材料催化了溴苯乙酮和4-溴苯甲醚(Heck)和4-氯苯甲醚(Suzuki)的Heck和Suzuki反应，但不能催化3-氯甲苯的反应。根据已知的化学催化作用，其催化效果与苯环上的吸电子取代基有关，其中4-溴苯并三氟化钠的转化率(Suzuki)超过90%。(C)2013年提交人。爱思唯尔出版，版权所有。
Five gram negative and two gram positive bacterial strains known for their heavy metal tolerance or ability to reduce metal ions were coated with Pd(0) nanoparticles (NPs) via reduction of soluble Pd(II) ions under H-2 following an initial uptake of PdCl42- without added electron donor ('biosorption'), where the gram negative strains had a similar to 5-fold greater capacity for Pd(II). Cupriavidis metallidurans accumulated Pd(II) exceptionally; the possibility of reduction to Pd(0) via an endogenous electron donor was not discounted. The initial rate of subsequent H-2-mediated Pd(II) reduction correlated with the Pd(II) removed during biosorption (r(2) = 0.9). TEM showed strain-specific variations of Pd-NPs. At a 1:3 loading of Pd:biomass the cell surfaces of Escherichia coli and Desulfovibrio desulfuricans showed uniform coverage with small NPs with the other strains showing larger aggregates. NPs made by the gram positive cells appeared larger than their gram negative counterparts. At a loading of 1:19 all were active catalysts in Cr(VI) reduction and in two Heck coupling reactions. BioPd(E. coli) and bioPd(D. desulfuricans) and bioPd(A. oxydans) were consistently the best and worst catalysts respectively. BioPd(E. culi) was further tested as a process catalyst according to industrial protocols in Fleck and Suzuki coupling reactions. Laboratory and industrial tests (coupling of phenyl iodide and ethyl acrylate) gave 75% and 78% conversion to ethyl cinnamate, respectively. The biomaterial catalysed Heck and Suzuki reactions using bromoacetophenone and 4-bromoanisole (Heck) and 4-chloroanisole (Suzuki) but not 3-chlorotoluene. In accordance with known chemical catalysis the catalytic efficacy was related to electron-withdrawing substituents on the phenyl ring, with more than 90% conversion (Suzuki) using 4-bromobenzotrifluoride. (C) 2013 The Authors. Published by Elsevier B.V. All rights reserved.