| Ag对Pd/CeO2-ZrO2-La2O3-Al2O3催化氧化甲醇性能的影响 |
| Effects of Ag on Performance of Methanol Oxidation over Pd/CeO2-ZrO2-La2O3-Al2O3 |
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| 摘要: 采用等体积共浸渍法制备了一系列Pd-Ag/CeO2-ZrO2-La2O3-Al2O3催化剂。运用N2吸附-脱附，X射线衍射(XRD)，H2程序升温还原(H2-TPR)，紫外-可见漫反射光谱(UV-Vis DRS)，X射线光电子能谱 (XPS)对催化剂进行表征，并考察其对甲醇的催化氧化性能。活性测试结果表明，Ag的添加可显著改善Pd催化剂对甲醇的催化氧化活性，T50、T90以及ΔT分别为125 ℃，150 ℃和25 ℃，具有较好的应用前景。H2-TPR表明，引入Ag可明显改善催化剂的还原性能，使表面易还原氧物种量增多，还原速率加快；UV-Vis DRS及XPS表明，Pd、Ag金属之间以及金属与载体之间存在电子效应，这种效应促使金属与载体界面产生大量具有活性的氧物种，不仅提高了催化剂的低温活性，还提高了催化剂的氧化速率。 |
| 关键词: 银 钯 铈 催化氧化 甲醇 |
| 基金项目: |
| Abstract: Pd-Ag/CeO2-ZrO2-La2O3-Al2O3 catalysts were prepared by the co-impregnation method. Low temperature nitrogen adsorption-desorption, X-ray diffraction (XRD), H2-temperature-programmed reduction (H2-TPR), Ultra violet-visble difuse reflectance spectroscopy (UV-Vis DRS) and X-ray photoelectron spectroscopy (XPS) were carried out. The catalytic activities of these catalysts for the oxidation of methanol were investigated. The results of catalytic activity indicate that the presence of Ag significantly improves catalytic performance for methanol oxidation. The T50, T90 and ΔT are 125 ℃, 150 ℃ and 25 ℃, respectively. H2-TPR results suggest that the addition of Ag increases the amount of active oxygen and promotes the reductive ability. The UV-Vis DRS and XPS results indicate that electron effects between Pd and Ag, Pd-Ag and support are favorable for producing larger activated oxygen via easy migration on the Pd-Ag/CeO2 interface, thus promoting both the catalytic activity at low temperature and the speed of catalytic oxidation. |
| Keywords: silver palladium cerium catalytic oxidation methanol |
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| 张雪乔,王世丹,信 欣,刘盛余,陈耀强,赵 明.Ag对Pd/CeO2-ZrO2-La2O3-Al2O3催化氧化甲醇性能的影响[J].无机化学学报,2012,28(8):1563-1569. |
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