油酸包覆型Fe_2O_3对铁厂沟煤加氢热解特性的影响

Impact of the Oleic Acid-coated Fe_2O_3 on the Hydropyrolysis Behavior of the Tiechanggou Coal

采用固定床反应器考察了干混法添加油酸包覆型Fe2O3对煤加氢热解特性的影响,并与添加常规Fe2O3进行比较。对其催化作用下得到的半焦进行了TG、BET和XRD表征,焦油进行GC模拟蒸馏分析。结果表明:(1)采用常规Fe2O3考察铁的添加量时,在添加量为5%时焦油产率最高,由不加催化剂时的14.3%提高到16.3%。添加油酸包覆型Fe2O3时,煤的热解转化率更高,焦油产率由不加催化剂时的14.3%提高到18.0%。(2)添加油酸包覆型Fe2O3和常规Fe2O3得到的半焦反应性基本相同,半焦的孔结构则是添加油酸包覆型Fe2O3时最发达;添加油酸包覆型Fe2O3的半焦表面Fe晶粒的直径28 nm,小于添加常规Fe2O3的半焦表面Fe晶粒的直径39.5 nm。(3)加入常规Fe2O3和油酸包覆型Fe2O3都使得焦油品质得到提高,但两者相比,常规Fe2O3作用下得到的焦油品质更高。

The impact of the oleic acid-coated Fe2O3 prepared by mechanically mixed method on the hydropyrolysis behavior was investigated in a fixed-bed reactor and compared with that which had been added with conventional Fe2O3. The produced char were characterized using TG, BET and XRD and the tar character was measured with the GC simulating distillation. The results showed that （1） When the addition amount of the conventional Fe2O3 was 5%, the tar yield was the highest, increasing from 14.3% （without catalysts） to 16.3%. Oleic acid-coated Fe2O3 was more effective on the increase of the total conversion and tar yield than the conventional Fe2O3, and the tar yield increased from 14.3%（without catalysts） to 18%. （2） The char reactivity was practically the same whether to add the conventional Fe2O3 or the oleic acid-coated Fe2O3. The pore structure of the char prepared from the oleic acid-coated Fe2O3 was better than others. The Fe grain size of the char surface prepared from oleic acid-coated Fe2O3 （28 nm） was smaller than that prepared from the conventional Fe2O3 （39.5 nm）. （3） Adding conventional Fe2O3 and the oleic acid-coated Fe2O3 could both improve the tar quality, but the tar prepared from the conventional Fe2O3 was better than that prepared from the oleic acid-coated Fe2O3.