Abstract: Catalytic cracking upgrading of coal pyrolysis oil and gas products was conducted in a dual-stage reactor using char and Co-impregnated char(Co-char)as the catalyst.The tested coal was Fugu coal,and the upper stage of the dual-stage reactor was used for pyrolysis.During catalytic cracking of coal pyrolysis products,tar yield decreased,and gas yield and also light oil fraction content of(boiling points<360℃) the tar increased,while the yield of light tar remained constant or increased slightly.For the pyrolysis with secondary cracking at 600℃ over a char layer of 20% the tested coal,its gas yield and light tar content increased respectively by 31.2%(vol)and 25%(mass)in comparison with the direct pyrolysis of coal at 600℃,whereas light tar yield varied little.When Co-char was used as the catalyst,cracking at 500℃ over the catalyst of 5% coal mass increased light oil yield and light oil content in the tar by 8.8%(mass),and 28.8%(mass),respectively.The corresponding increase in gas yield was 21.5%(vol).Catalytic secondary cracking in coal pyrolysis worked mainly to convert heavy oil components into light oil and pyrolysis gas.

Key words: coal pyrolysis, catalytic cracking, char, coal tar, cobalt catalyst

摘要： 利用上段热解下段催化的两段固定床反应器,针对府谷煤研究了半焦和半焦负载Co催化剂对煤热解产物的催化裂解效果。结果表明,半焦和半焦负载钴对热解产物催化裂解后,热解气收率增加,焦油收率降低,但焦油中沸点低于360℃的轻质组分含量提高,轻质焦油收率基本保持不变或略有增加。与煤在600℃直接热解相比,在热解和催化温度均为600℃,采用煤样质量20%的半焦为催化剂时焦油中轻质组分质量含量提高了约25%,轻质组分收率基本不变,热解气体积收率增加了31.2%;在热解温度600℃,催化温度500℃时,采用煤样质量5%的半焦负载钴催化剂,焦油中轻质组分质量收率和含量分别提高了约8.8%和28.8%,热解气体积收率增加了21.5%。煤热解产物的二次催化裂解的总体效果是将焦油中重质组分转化为轻质焦油和热解气。

关键词: 煤热解, 催化裂解, 半焦, 煤焦油, 钴催化剂