硫化合物对Pt-Sn-K/Al2O3催化剂催化异丁烷脱氢性能的影响

摘要

The influence of sulfur compounds on the performance of Pt-Sn-K/Al2O3 catalyst for isobutane dehydrogenation reaction was investigated in a fixed-bed reactor. The results showed that, under the reaction conditions of 580℃, 0.1MPa, V (H2)/V(i-C4H10) of 2 in the feedstock, GHSV for total feedstock of 2000h-1, and GHSV for i-C4H10 of 667h-1, the addition of ethanethiol, diethyl sulfide and carbon disulfide led to a decline of isobutane conversion and a rise of isobutene selectivity; and the higher the concentration of sulfur compounds in the feedstock was, the larger the decline of the dehydrogenation activity of the catalyst was. When the mass fraction of sulfur from the sulfur compounds in feedstock was 200 ×10-6, the toxicity of different sulfur compounds on the dehydrogenation activity of Pt-Sn-K/AI2O3 catalyst was as follows: C4H4S (thiophene)>EtSH≈Et2S≈CS2≈PrSH≈H2S. The poisoning of Pt-Sn-K/Al2O3 catalyst caused by sulfur compounds was reversible.%在固定床反应器中考察了常见硫化合物对Pt-Sn-K/Al2O3催化剂催化异丁烷脱氢活性的影响。实验结果表明，在温度580℃、压力0.1MPa、进料组成V(H2)：V(i-C4H10)=2：1、总空速GHSV=2000h-1和GHSV(i-C4H10)=667h-1的条件下反应，乙硫醇、乙硫醚和二硫化碳使Pt-Sn-K/Al2O3催化剂的异丁烷转化率下降，异丁烯选择性上升；且随原料中硫含量的增加，异丁烷脱氢活性下降的程度增大。在原料硫质量分数为200×10-6的条件下，硫化合物对Pt-Sn-K/AI2O3催化剂的异丁烷脱氢毒性大小顺序为：噻吩>EtSH≈Et2S≈CS2≈PrSH≈H2S。硫化合物导致的Pt-Sn-K/Al2O3催化剂中毒为可逆中毒。