异丁烷脱氢裂解制低碳烯烃

DEHYDROGENATION CRACKING OF i-BUTANE TO PRODUCE LIGHT OLEFINS

以异丁烷为原料,在固定床微反实验装置上考察了其在Cr2O3/Al2O3脱氢催化剂和HZSM-5催化剂组成的混合催化剂上脱氢裂解反应的情况。研究发现:两种催化剂在反应器中的分布状态以及Cr2O3/Al2O3催化剂的装填量都会对反应结果产生很大的影响,当两者均匀混合、Cr2O3/Al2O3催化剂的添加量为20%时,裂解反应效果最佳,转化率达到80.99%,三烯总收率为50.26%,其中乙烯、丙烯和丁烯的收率分别为12.42%,24.41%,13.43%;相比于单纯的HZSM-5催化剂,异丁烯转化率提高了21.22百分点,三烯的选择性提高了2.57百分点。此外,反应过程中采用异丁烷和惰性稀释气(N2)混合进料时,反应效果更佳,而且随稀释比增大,优势更明显。

The dehydrogenation cracking of/-butane was studied over mixed catalysts comprised of Cr203/Al2O3 dehydrogenation catalyst and HZSM-5 catalyst in a fixed-bed reactor. The results demon- strate that conversion and product distribution vary significantly depending on different location of Cr203/Al2O3 and HZSM-5 catalyst and the amount of Cr203/Al2O3 catalyst in the reactor, and the reac- tion performance is the best when two kinds of catalysts are homogeneously mixed. On the mixed cata- lyst HZSM-5 with a 20% Cr2O3/A1203, the conversion of reaction is 80.99%, and the yield of ethylene, propylene and butylene is 12.42%, 24.11% and 13.43%, respectively. The conversion increases by 21.22 percentage points and the selectivity of total olefins （ethylene, propylene and butylene） increases by 2.57 percentage points, compared with the pure HZSM-5. Besides, i-butane mixed with N2 enters the reactor at a fixed residence time of i-butane, the reaction results become better, and the advantage is more obvious as dilution ratio increases.