MCM-41分子筛负载金属酞菁在氧化脱硫反应中的催化性能

Catalytic performance of metal phthalocyanine loaded on MCM-41 molecular sieve in oxidation desulfurization

采用浸渍法将8种金属酞菁分别负载到MCM-41分子筛上制得负载型金属酞菁,通过红外光谱进行表征。以二苯并噻吩(DBT)为反应底物,空气为氧化剂,己内酰胺四丁基溴化铵离子液体为溶剂考察了这8种催化剂在氧化脱硫反应中的催化活性,筛选出较优催化剂,并对工艺条件进行优化。结果表明,合成的8种负载型金属酞菁催化剂中,MCM-41分子筛负载钴酞菁具有较好的催化性能,最优工艺条件为:剂油比1:1,催化剂用量0.004g·(10 ml模型油)-1,空气流速50 ml·min-1,反应时间1 h,室温,DBT脱硫率最高可达97.56%。DBT的氧化产物为DBT砜。又考察了此催化氧化系统对不同硫化物的催化氧化效果,发现不同硫化物的脱硫率均在90%以上。该催化剂在重复利用4次后脱硫率无明显的降低。

Eight kinds of metal phthalocyanine （Pc） were loaded into MCM-41 by impregnation method,and were characterized by infrared spectrum. The catalytic activities of the eight supported metal phthalocyanine in the desulfurization were investigated with dibenzothiophene （DBT） as the reaction substrate, air as oxidant and caprolactam-tetrabutylammonium bromide ionic liquid as solvent. The reaction condition was investigated in detail. The results showed that MCM-41/CoPc was the best catalyst among the eight supported metal phthalocyanine catalysts. The removal ratio of DBT is up to 97.56%for 1 h under the optimal reaction condition （the ratio of ionic liquid to model oil 1：1, the amount of catalyst 0.004 g·（10 ml model oil）-1, air flow rate 50 ml·min-1 and room temperature）. The oxidized product of DBT is DBT sulphone. Different sulfur compounds were also investigated. The result shows that sulfur removal of different sulfur all are up to 90%. The removal ratio of DBT doesn’t decrease obviously, after reused for four times with this catalyst.