Nitrate reduction by maghemite supported Cu-Pd bimetallic catalyst
Nitrate reduction by maghemite supported Cu-Pd bimetallic catalyst
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DOI：
10.1016/j.apcatb.2012.08.017
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发表时间：
2012-10-30
影响因子：
22.1
通讯作者：
Lee, Woojin
中科院分区：
文献类型：
--
作者：
Jung, Junyoung;Bae, Sungjun;Lee, Woojin
研究了磁赤铁矿负载Cu-Pd催化剂（磁赤铁矿/Cu/Pd）催化还原硝酸盐的反应。采用BET、XRD、XPS、TPR、SEM/EDX、TEM等测试手段对磁赤铁矿/Cu/Pd进行了表征。磁赤铁矿/Cu/Pd催化剂在90 min内对硝酸盐的去除率达到99.5%，而氧化铝和赤铁矿负载的Cu-Pd催化剂对硝酸盐的去除率分别为43%和63%。在所有Cu负载变化（0.25-1重量%）中，硝酸盐去除是优异的（>95%）。当Cu/Pd比为0.5/0.5wt.%时，反应生成的氮气的选择性最高（43%）。我们还观察到磁赤铁矿/Cu/Pd在Pd负载量（0.25-1重量%）范围内的优异的硝酸盐去除率（分别>95和> 94%）。和氢气流速（100-500 cc/min）。最高的氮选择性（47和45%）通过低Pd负载（0.25wt.%）获得。和氢气流速（200 cc/min）。磁赤铁矿/Cu/Pd在三个反应周期中显示出硝酸盐去除率（99.5-83%）和低金属浸出（1.5%的Cu浸出）的缓慢下降。XPS分析表明，Cu（0）在催化还原过程中被氧化为Cu 2 O和CuO，而Pd（0）没有发生变化。(C)2012爱思唯尔有限公司版权所有。
We have investigated the catalytic nitrate reduction by maghemite supported Cu-Pd bimetallic catalyst (maghemite/Cu/Pd). BET, XRD, XPS, TPR, SEM/EDX, TEM analysis were carried out to characterize maghemite/Cu/Pd. Remarkable nitrate removal (99.5%) by maghemite/Cu/Pd was observed in 90 min, while Cu-Pd catalyst supported with alumina (43%) and hematite (63%) showed less efficient nitrate removal. Nitrate removal was excellent (>95%) in all Cu loading variation (0.25-1 wt.%) on maghemite/Cu/Pd, while selectivity of nitrogen gas formed during the reaction was the highest (43%) at a specific Cu/Pd ratio (0.5/0.5 wt.%). We also observed excellent nitrate removals (>95 and >94%, respectively) by maghemite/Cu/Pd in the ranges of Pd loading (0.25-1 wt.%) and hydrogen flow rate (100-500 cc/min). The highest nitrogen selectivities (47 and 45%) were obtained by low Pd loading (0.25 wt.%) and hydrogen flow rate (200 cc/min). Maghemite/Cu/Pd showed slow decrease of nitrate removal (99.5-83%) and low metal leaching (1.5% of Cu leaching) during three reaction cycles. XPS analysis revealed that Cu(0) was oxidized to Cu2O and CuO during the catalytic nitrate reduction, while Pd(0) was not changed. (C) 2012 Elsevier B.V. All rights reserved.