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探讨膨润土负载双金属铁钯(B-Fe/Pd)纳米材料催化降解微囊藻毒素-LR(MC-LR)的效果和机理.结果表明,在5mgL-1的MC-LR溶液中加入0.1g的纳米B-Fe/Pd,初始pH为6.86,振荡速度为250rmin-1,温度为298K的条件下,经过180min后对MC-LR的降解效率达96.86%.降解溶液的UV-vis和HPLC结果表明,MC-LR在238nm的特征峰消失.通过SEM-EDS、XRD、FTIR和XPS技术对B-Fe/Pd降解前后的样品进行表征,结果显示,降解后纳米B-Fe/Pd中的Fe形成了Fe的氧化物与氢氧化物.降解过程的动力学拟合结果显示,B-Fe/Pd降解MC-LR符合伪一级动力学,活化能为12.77kJmol-1.根据降解、表征和动力学结果分析其反应机理,推断是MC-LR首先吸附在B-Fe/Pd颗粒表面,接着纳米铁与水反应产生的氢气在Pd的催化作用下产生大量的氢自由基,并与MC-LR发生链式还原反应,使得MC-LR中最具毒性的共轭双键断开而降解.
To investigate the effect and mechanism of bentonite-supported bimetallic iron-palladium (B-Fe / Pd) nanomaterials for MC-LR degradation by MC-LR.The results showed that 0.1g Of nano-B-Fe / Pd, the initial pH was 6.86, the oscillation speed was 250rmin-1 and the temperature was 298K, the degradation efficiency of MC-LR reached 96.86% after 180min.The UV-vis and HPLC results The results showed that the characteristic peak of MC-LR disappeared at 238nm.The samples before and after degradation of B-Fe / Pd were characterized by SEM-EDS, XRD, FTIR and XPS. The results showed that the degradation of Fe The formation of Fe oxides and hydroxides.Degradation process kinetics fitting results show that B-Fe / Pd degradation of MC-LR in line with pseudo-first-order kinetics, activation energy of 12.77kJmol-1. According to degradation, characterization and Kinetic analysis of the reaction mechanism, it is inferred that the first adsorption of MC-LR on the surface of B-Fe / Pd particles, followed by the reaction of nano-iron and water generated hydrogen in the Pd catalytic hydrogen radical generated a large number of and MC- LR occurs chain reduction reaction, making MC-LR in the most toxic conjugate double bond to break down.