【作者】 汤吉；

【导师】 方奕文；

【作者基本信息】 汕头大学 ， 工业催化， 2010， 硕士

【摘要】 我国是一个富煤、缺油的国家,随着经济的发展,环境污染问题也日益突出。因此,寻找低污染的替代能源成为当务之急。随着二甲醚生产技术的成熟,产量的大幅提升,二甲醚凭借低污染,以及良好的燃烧性能,成为替代能源的良好选择,必将在民用燃料和车用燃料领域得到广泛的应用。本文选用二甲醚和空气为原料气,考察了二甲醚在Cu-Ce/γ-Al2O3、3%Cu-Ce-La/γ-Al2O3、3% Zr1-xCuxO2-x/γ-Al2O3、Zr1-xCuxO2催化剂以及以介孔γ-Al2O3为载体的5%Cu-Ce/γ-Al2O3催化剂上的催化燃烧活性。结果如下:1. Cu-Ce/γ-Al2O3催化剂在二甲醚催化燃烧反应中起主要作用的是Ce和Cu固溶体,固溶体的形成提高了催化剂的催化性能。在该催化剂上二甲醚的氧化产物中没有一氧化碳,氧化完全。2.不同负载量的Ce0.1Cu0.9O1.1/γ-Al2O3催化剂上二甲醚催化燃烧结果表明:负载量小于6%时,活性组分和固溶体能很好的分散在载体γ-Al2O3上,催化效果较好。当负载量过大时,影响了活性组分在载体γ-Al2O3上的分散,使得催化性能不再变化,甚至降低。在该类催化剂上,二甲醚氧化产物中都没有一氧化碳。3.适量的La掺杂可以提高Ce0.1Cu0.9O1.1/γ-Al2O3催化剂的二甲醚催化燃烧活性。在La0.4-Ce0.1Cu0.9O1.1 /γ-Al2O3催化剂催上,二甲醚催化燃烧化性能最好,其起燃温度(即二甲醚转化率达到10%的温度,记作T10)为235℃,完全转化温度(即二甲醚转化率达到90%的温度,记作T90)为244.8℃。但当温度达到起燃温度后,有一氧化碳生成,二甲醚催化氧化不完全。4.以有机小分子为模板剂,硝酸铝为铝源制备的γ-Al2O3为介孔材料。其中以葡萄糖为模板剂制备的γ-Al2O3比表面积和孔体积较大,孔径分布和晶体形态较好。以其作为载体制备的γ-Al2O3-glu催化剂在二甲醚的催化燃烧反应中展现出较好的性能。5. 5% La0.4-Ce0.1Cu0.9O1.1/γ-Al2O3-glu催化剂上,二甲醚催化燃烧性能要好于其它催化剂,其起燃温度为220℃,完全转化温度为224℃,产物中有少量一氧化碳生成。经过100h寿命实验,催化剂上DME的转化率未见降低,催化剂稳定性良好。6.共沉淀法制备的Zr1-xCuxO2催化剂上,二甲醚催化燃烧起燃温度最低的是Zr0.4Cu0.6O2催化剂,其T10=261.5℃,完全转化温度最低的是Zr0.1Cu0.9O2和Zr0.2Cu0.8O2催化剂上,其T90=279℃。溶胶-凝胶法制备的Zr1-xCuxO2催化剂上,二甲醚的催化燃烧性能最好的是Zr0.3Cu0.7O2催化剂,其起燃温度为255℃,完全转化温度为259.7℃。等体积浸渍法制备的3%Zr1-xCuxO2-x /γ-Al2O3(x=0~0.9)催化剂上,3%Zr0.1Cu0.9O1.1 /γ-Al2O3催化剂上二甲醚的催化燃烧活性最好,其起燃温度为217.8℃,完全转化温度为244.7℃。Zr掺杂使得二甲醚催化燃烧不完全,有较多副产物,尤其一氧化碳生成量较高。7.钙钛矿型LaMnO3、CaMnO3和BaMnO3催化剂上二甲醚催化燃烧都较好,其中性能最好的是LaMnO3催化剂,其起燃温度为215.3℃,完全转化温度为219.9℃,但催化剂稳定性较差。更多还原

【Abstract】 The states of energy sources is“a coal-rich, short of petroleum”in the China. Along with economic development, environmental pollution will be more and more serious. Therefore, the searching for less polluting alternative energy sources becomes a priority. DME production technology has been maturity, and then yield increases significant. Now dimethyl ether with low pollution and good combustion properties, is a good selection of alternative energy sources. DME will be widely used in the civilian areas of fuel and vehicle fuel.In this thesis, the catalytic performances of Cu-Ce/γ-Al2O3、3%Cu-Ce-La/γ-Al2O3、3% Zr1-xCuxO2-x/γ-Al2O3、Zr1-xCuxO2、5%Cu-Ce carried mesoporousγ-Al2O3 catalysts for the combustion of DME with air were studied. The results are summarized as follows:1. The main catalyst of Cu-Ce/γ-Al2O3 catalyst for catalytic combustion of dimethyl ether was the Ce and Cu solid solution, and solid solution improved catalytic performance. The oxidation productions of dimethyl ether were without carbon monoxide.2. Ce0.1Cu0.9O1.1/γ-Al2O3 catalysts with different loadings were performed to investigate the catalytic combustion of dimethyl ether shows: loading less than 6%, the active component and solid solution dispersed well on theγ-Al2O3, and the catalytic effect is good. When the excessive loading, the catalytic activity made no changes, or even lower, because the effect of active components on theγ-Al2O3 dispersed. And varies loadings of catalyst, dimethyl ether oxidation products were not carbon monoxide.3. La doping can improve the performance of the Ce0.1Cu0.9O1.1/γ-Al2O3 catalyst, but when excessive doped catalysts, the catalytic activity reduced. Among them, La0.4-Ce0.1Cu0.9O1.1 /γ-Al2O3 catalyst of the catalytic combustion of dimethyl ether was the best performance, and the combustion temperature (DME conversion reached 10% of the temperature, denoted by T10) was 235℃, complete conversion temperature (the conversion of dimethyl ether 90% of the temperature, denoted T90) for the 244.8℃. But when the temperature reached the ignition temperature, there were carbon monoxide, so dimethyl ether oxidation was incomplete.4. Mesoporous materialsγ-Al2O3 preparated by organic small molecule as a template and aluminum nitrate as the aluminum source. Among them, glucose as the template preparedγ-Al2O3 has larger surface area and pore volume, pore size distribution and crystal shape better. And as the carrier prepared by catalyst, the catalyst studied on the catalytic combustion of dimethyl ether. Results showed that: thisγ-Al2O3-glu could promote the catalyst performance.5. Catalytic activity of 5% La0.4-Ce0.1Cu0.9O1.1/γ-Al2O3-glu catalyst was better than the other catalysts. Its T10 was 220℃, and T90 was 224℃, the production had a small amount of carbon monoxide. The life time of catalyst was investigated, and the result indicated that the catalyst activity had not any reduce after 100h reaction.6. Among the co-precipitation of Zr1-xCuxO2 catalysts, ignition temperature of Zr0.4Cu0.6O2 catalyst was the lowest, that is, T10 =261.5℃. And Zr0.1u0.9O2 and Zr0.2Cu0.8O2 catalysts exhibited the lowest complete conversion temperature , that is, T90= 279℃. Among the sol-gel of method Zr1-xCuxO2 catalysts, Zr0.3Cu0.7O2 catalyst was the best catalyst for the catalytic combustion of dimethyl ether. Its T10 was 255℃and T90 was 259.7℃. Among the 3% Zr0.1Cu0.9O1.1 /γ-Al2O3 catalyst by impregnation method, 3%Zr1-xCuxO2-x /γ-Al2O3(x=0~0.9) catalyst exhibited the best catalytic performance for DME combustion, and T10 was 217.8℃, T90 was 244.7℃Zr doping made the DME catalytic combustion incompletely, and there were more by-products, especially carbon monoxide was higher.7. Perovskite catalyst of LaMnO3, CaMnO3 and BaMnO3 catalysts had better performance for catalytic combustion of dimethyl ether, in which LaMn03 was the best one, and T10 was 215.3℃, and T90 was 219.9℃, but the catalyst was less stable.更多还原