Mn-Ce-O催化剂组成对氨超临界水氧化性能的影响  

Composition-activity effect of Mn-Ce-O composites on NH_3 catalytic supercritical water oxidation

作　　者：彭文才[1] 张荣[1] 毕继诚[1] 

机构地区：[1]中国科学院山西煤炭化学研究所煤转化国家重点实验室

出　　处：《燃料化学学报》2007年第6期727-731,共5页Journal of Fuel Chemistry and Technology

基　　金：国家自然科学基金(20506028);山西省自然科学基金(20051024)。

摘　　要：用共沉淀方法制备了锰铈摩尔比分别为10/0、8/2、6/4、5/5、4/6、2/8和0/10的七种Mn-Ce-O复合氧化物催化剂。在450℃、25MPa、停留时间1s和氧化剂量为化学计量2.94倍的条件下,利用连续超临界水氧化反应装置考察了催化剂组成与其催化氨降解性能的关系。结果表明,催化剂组成与其活性间有着强烈的相关性,锰铈摩尔比为5/5的催化剂表现出最高的活性,氨转化率达到99.7%。用低温N2吸附、X射线衍射以及程序升温还原等方法表征了催化剂比表面积、物相结构和氧化还原性能,揭示了Mn和Ce的氧化物之间存在协同作用。In order to investigate the relationship between the composition and the activity of Mn-Ce-O composites, 7 samples with Mn/Ce molar ratios of 10/0, 8/2, 6/4, 5/5, 4/6, 2/8, 0/10 were prepared by co-precipitation. NH3 was selected as a model pollutant and H2O2 was used as oxidant. The oxidation reaction in supercritical water was carried out in a continuous flow packed-bed reactor at th temperature of 450°C, the pressure of 25 MPa, and the residence time of 1s with the oxidant addition of 2.94 times the stoichiometric amount. The catalytic activity is greatly influenced by the catalyst composition and the catalyst with Mn/Ce mol ratio of 5/5 is found to be the best one, on which the conversion of NH3 can reach to 99.7%. The catalysts were characterized by N2 adsorption, XRD and TPR. The results indicate that there exists an interaction between Mn and Ce oxides.

关 键 词：氨 超临界水氧化 催化 组成 

分 类 号：TQ038.2[化学工程]