不同前驱物对Ni催化剂上甲烷部分氧化制合成气反应的影响

Effects of Nickel Precursors on Partial Oxidation of Methane to Syngas over Ni/Al_2O_3 Catalysts

考察了由硝酸镍 ,醋酸镍和氯化镍为前驱物制备的催化剂 (分别记为Ni N ,Ni Ac和Ni Cl)对催化甲烷部分氧化反应的影响 ,并结合TPR ,XRD和TG等手段对催化剂进行了表征 .结果表明 ,Ni Ac催化剂在 6 2 5℃就能自引发甲烷部分氧化反应 ,而在Ni N和Ni Cl催化剂上 ,直到 75 0℃甲烷部分氧化反应仍未能引发 .三种催化剂上的反应结果表明 ,Ni N和Ni Ac的催化活性较高 ,Ni Cl的催化活性较低 .90 0℃下的高温反应结果表明 ,Ni N具有较强的的抗烧结能力 ,而Ni Ac的抗烧结能力较差 .在n(CH4) /n(O2 ) =2 4,θ =80 0℃下 ,Ni N和Ni Ac使用 2 0h后表面明显积碳 ,而Ni Cl表面几乎无积碳 ,表明Ni

The effects of Ni precursors, such as Ni(NO 3) 2, NiAc 2 and NiCl 2 (corresponding catalysts were named Ni N, Ni Ac and Ni Cl respectively), on the reaction performance of partial oxidation of methane (POM) were investigated, and the catalysts were characterized by TPR, XRD and TG techniques. The results showed that POM could be automatically initiated on Ni Ac, however, it could not be initiated on the other catalysts. Ni N and Ni Ac exhibited higher catalytic activity than Ni Cl. Ni N had the strongest resistance to sintering during the reaction at high temperature (900 ℃) among the catalysts. It was shown that the carbon deposition could be found on Ni N and Ni Ac, however, almost no remarkable carbon deposition was observed on Ni Cl after running at 800 ℃ for 20 h with n (CH 4)/ n (O 2)=2 4.