摘要
以TiCl4为原料合成了TiO2/!-Al2O3载体.在色谱-微反流动法反应装置上考察了CuO/15%(w,下同)TiO2/!-Al2O3系列催化剂对NO+CO的反应性能.结果表明上述催化剂对NO+CO反应表现出较好的活性,其中12%CuO/15%TiO2/!-Al2O3反应活性最佳.空气和H2预处理后,NO完全转化的温度分别为300℃和275℃.通过H2-TPR、XRD和FT-IR等技术表征,发现适量TiO2能促进CuO在钛铝载体上的分散.TPR结果显示12%CuO/15%TiO2/!-Al2O3在整个TPR过程中出现四个还原峰,α和γ还原峰分别是钛铝载体表面裸露的TiO2上高度分散的CuO和晶相CuO的还原;β和$还原峰为钛铝载体上高度分散的CuO和晶相CuO的还原.FT-IR实验表明NO和CO在经H2气氛预处理的催化剂表面上吸附较强,且生成了N2O和NO2等物种;NO+CO混合气在经空气和H2预处理的催化剂表面吸附时,出现了N2O吸收峰,峰温分别为200℃和150℃.
TiO2/γ-Al2O3 was prepared with TiCl4 as starting material, and the catalytic activities of CuO/TiO2/γ-Al2O3 were examined using a GC micro-reactor NO＋CO reaction system. The catalysts, especially 12%CuO/TiO2/γ-Al2O3, showed high activities in NO＋CO reaction. The NO conversion temperatures（T100%） were 300 ℃ and 275 ℃ for the catalysts pretreated by air and H2, respectively. The structural and reduction properties of CuO/TiO2/γ-Al2O3 catalysts were analyzed using the H2-TPR, XRD, and FT-IR methods. It was found that proper amount of TiO2 increased the CuO dispersion on TiO2/γ-Al2O3. The 12%CuO/TiO2/γ-Al2O3 catalyst had four reduction peaks （α, β, γ, and δ）. The a and y peaks were attributed to the reductions of highly dispersed CuO and crystalline CuO on the exposed TiO2 of TiO2 / y-Al2O3, respectively. On the other hand, the β and δ peaks were attributed to the reductions of highly dispersed CuO and crystalline CuO on TiO2/γ-Al2O3, respectively. H2-pretreated 12%CuO/15%TiO2/γ-Al2O3 had a strong adsorption of NO and CO, N2O and NO2 were formed. When NO and CO were adsorbed by 12%CuO/15%TiO2/γ-Al2O3 the peak temperatures of N2O absorption were 200 ℃ and 150 ℃ for the catalysts pretreated by air and H2, respectively.
出处
《物理化学学报》
SCIE
CAS
CSCD
北大核心
2006年第5期584-589,共6页
Acta Physico-Chimica Sinica
基金
浙江省自然科学基金(Y504131)资助项目
