摘要
考察了担载Ni催化剂在CH4 CO2重整反应中的催化活性,发现Ni/Al2O3的初活性较高,但随反应温度的升高而下降;Ni/CeO2具有较高的CH4转化活性,且随反应温度的升高变化不大,但对CO2的活性很低;Ni/TiO2对CH4及CO2的活性均很差。CeO2的加入对反应活性及其抗积炭性能有显著的影响。1023K反应40h后的寿命实验结果表明,Ni/CeO2/Al2O3催化剂不仅具有很高的CH4及CO2转化活性(转化率分别为96%和86%),而且显示出良好的抗积炭性能(积炭量2 4mg/g cat/h);而Ni/CeO2/TiO2的反应活性甚至不及Ni/TiO2。选用不同的Ni盐,反应活性亦有较大差异。以硝酸镍、醋酸镍及硝酸六氨合镍为前体制备的Ni/CeO2/Al2O3催化剂初活性较高,且不易积炭;以氯化镍为前体制备的Ni催化剂虽然初活性较高,但积炭量也高;而以硫酸镍为前体制备的Ni催化剂活性很差。
CeO2/Al2O3 and CeO2/TiO2 supported Ni catalysts were prepared Their catalytic acitivites in CO2 reforming of CH4 are evaluated It has been found that Ni/CeO2/Al2O3 catalyst showed higher activity than Ni/CeO2 and better stability than Ni/Al2O3 After reacting with time on stream at 1023 K for 40 h, the conversions of CH4 and CO2 were 96% and 86%, respectively The addition of CeO2 markedly improves the stability and enhances the resistance to carbon deposition of the catalyst For Ni/TiO2 or Ni/CeO2/TiO2 catalyst, very low activities are found, possibly due to reducibility of TiO2 The catalytic activity was also affected by Ni precursor used The nickel catalysts based on nickel nitrate, nickel acetate and hexaamminenickel nitride as precursors, respectively, was found to have higher activity and less coking than nickel chlorideor nickel sulfatederived catalyst
出处
《天然气化工—C1化学与化工》
CAS
CSCD
北大核心
2003年第2期19-22,共4页
Natural Gas Chemical Industry
