MCM-48分子筛催化剂上正庚烷的临氢异构化

Research of n-heptane hydroisomerization over MCM-48 molecular sieve catalysts

制备了Ni-PMo12/MCM-48中孔分子筛催化剂并用于正庚烷异构化反应研究。采用XRD、BET吸附、红外吡啶吸附等方法对催化剂进行表征。研究了反应温度、还原温度、还原时间和还原氢气流速对异构化催化性能的影响,并考察了催化性能随时间的变化。结果表明,当镍(Ni)和磷钼酸(PMo)质量分数分别为3%和30%、Ni-PMo/MCM-48对正庚烷异构化反应具有较好的异构化性能,还原温度400℃、还原4h、氢气流速为30mL/min、反应温度300℃时,催化剂性能最好,转化率为14.2%时,异构化选择性达到65.6%。

The catalytic performance of n-heptane isomerization on Ni-PMo/MCM-48 was discussed. The catalysts were characterized by using XRD, BET surface area and Py-IR. The effect of reaction temperature, reduction temperature, reduction time, and reduction hydrogen flowrate on the catalytic performance were studied. The result showed that with Ni content 3% and PMo content 30%, reduction temperature 400 ℃, reduction time 4 h, reduction hydrogen flowrate 30 mL/min, and reaction temperature 300℃, the activity of Ni-PMo12/MCM-48 was the best, the conversion of n-heptane was 14.2%, and isomerization selectivity to i-heptane could reach 65.6%.