镍负载量对自热转化催化剂Ni/γ-Al_2O_3性能的影响

EFFECT OF NICKEL CONTENT IN CATALYST ON THE PROPERTY OF AUTOTHERMAL REFORMING CATALYST

利用常压固定床微反色谱联用装置、X 射线衍射 (XRD)以及程序升温还原等分析手段 ,考察了镍负载量对自热转化催化剂Ni/γ Al2 O3 的活性和还原性能的影响。实验结果表明 ,对于 10 0 0℃下焙烧的模型催化剂Ni/γ Al2 O3,用XRD检测均未发现NiO(2 0 0 )特征峰 ;而当镍含量达到 8.1%时 ,XRD可检测到以尖晶石形式存在的镍。模型催化剂中NiAl2 O4 的还原性能低于NiO。催化剂中镍的负载量在一定范围内增加 ,可使起始还原温度下降 ,催化剂转化活性升高。分析结果表明 ,镍负载量为 7.7%的催化剂还原温度低 ,转化活性很好 ,能有效地抑制催化剂的积炭 。

The effects of nickel content in catalyst on the activity and reducibility of the autothermal reforming catalyst were investigated on fixed\|bed reactor by using XRD and TPR methods. It is found that NiAl\-2O\-4 exists in the model catalyst calcined at 1000 ℃ when the content of nickel in catalyst is more than 8.1%. Meanwhile, the catalyst with high content of nickel can be reduced at lower temperature. The increase in nickel content of catalyst in a certain range can reduce the reductive temperature and raise the activity of catalyst. XRD analysis proves that the catalyst with 7.7% nickel content has good performances and can be prevented from coking.