Department of Civil and Environmental Engineering, National University of Kaohsiung, Taiwan.
Water Sci Technol. 2010;62(1):202-8. doi: 10.2166/wst.2010.303.
Zero-valent aluminum based trimetallic particles comprising a combination of catalytically effective amounts (1 wt%) of palladium and zero-valent iron on the aluminum surface were synthesized and tested for the dechlorination of chlorinated methanes in batch reactors. XRD analysis indicated the trimetallic particles present in zero-valent form of all three components. Trimetallic Pd/Fe/Al particles showed a very rapid degradation of carbon tetrachloride leading to a surface normalized rate constant (k(SA)) of approximately 0.03 L/h/m(2), two orders of magnitude higher than that of reported data on zero-valent iron particles under near neutral pH conditions. Hydrocarbons including methane and ethane were the major products that accounted for about 38% and 27% of the carbon tetrachloride lost, respectively. Repetitive addition of carbon tetrachloride showed no loss of activity of Pd/Fe/Al particles for more than 20 cycles. In the absence of palladium, the degradation rate decreased by a factor of 10 suggesting palladium serves as a catalyst. Analysis of anions in the solution revealed that the chloride accounted for 75% of the carbon tetrachloride lost. Metallic ions for aluminum and iron were determined to be about 0.02 and 20 mg/L, respectively at the end of the experiment. No palladium ion was measured.
合成了包含催化有效量（1wt%）钯和零价铁的零价铝基三金属颗粒，并在间歇式反应器中测试了它们对氯化甲烷的脱氯性能。XRD 分析表明三金属颗粒以三种组分的零价形式存在。三金属 Pd/Fe/Al 颗粒对四氯化碳具有非常快速的降解作用，导致表面归一化速率常数（k(SA)）约为 0.03 L/h/m(2)，比在近中性 pH 条件下报道的零价铁颗粒的数据高两个数量级。包括甲烷和乙烷在内的碳氢化合物是主要产物，分别占四氯化碳损失量的 38%和 27%。重复添加四氯化碳表明，Pd/Fe/Al 颗粒的活性在 20 个循环以上没有损失。在没有钯的情况下，降解速率降低了 10 倍，表明钯起到了催化剂的作用。对溶液中阴离子的分析表明，氯离子占四氯化碳损失量的 75%。实验结束时，确定铝和铁的金属离子分别约为 0.02 和 20 mg/L，未测量到钯离子。
