摘要
制备了 Co Cu Al、Co Cu Mg、Co Cr Al、Co Ni Al等 4种水滑石类复合氧化物 .XRD谱图表明 ,在焙烧前 ,它们具有水滑石结构 .同时考察了它们的 CO+NO反应性能 .研究了催化剂组分对 CO+NO反应性能的影响和空速对催化剂 Co Cu Al反应活性的影响 .实验结果表明 ,具有组成 (摩尔比 )为 Co Cu Al(7∶ 1∶ 1)、Co Cu Mg(3∶ 1∶2 )、Co Cr Al(7∶ 1∶ 1)、Co Ni Al(5∶ 1∶ 1)的催化剂 ,在较低温度下对 NO的消除效果最好 ,且它们的活性顺序为 :Co Cu Al>Co Cr Al>Co Ni Al>Co Cu Mg.其中 ,前 3种催化剂都具有较高的低温活性 ,Co Cu Al类化合物在10 0℃可将 NO完全转化 .反应空速在 180 0 0 h- 1以下 ,对催化剂 Co Cu Al的低温活性影响不大 .
Four kinds of composite oxides from hydrotalcite like compound, viz CoCuAl, CoCuMg, CoCrAl and CoNiAl, were synthesized and were used as catalysts in the CO+NO reaction. XRD patterns shows that they have hydrotalcite structure before calcination. Effects of compositions on the activities of catalysts in the CO+NO reaction and GHSV on the activity of CoCuAl were investigated. The experimental results shows that the hydrotalcite like compounds CoCuAl, CoCuMg, CoCrAl and CoNiAl with molar ratios 7∶1∶1, 3∶1∶2, 7∶1∶1 and 5∶1∶1, respectively, have excellent activity for NO removal at low temperature within the range of investigation. The activities for NO removal decrease in the order of CoCuAl>CoCrAl>CoNiAl >CoCuMg. The first three catalysts have high activity at low temperature, and CoCuAl hydrotalcite compound can remove NO completely only at 100 ℃. The effect of GHSV on the activity of CoCuAl at low temperature is small below 18 000 h -1 .
出处
《分子催化》
EI
CAS
CSCD
北大核心
2000年第4期270-274,共5页
Journal of Molecular Catalysis(China)
