稠油模型化合物水热裂解生成H_2S实验研究

Experimental study on the formation of H_2S by aquathermolysis of heavy oil model compounds

针对注汽热采过程产生硫化氢(H_2S)现象,以稠油的4种模型化合物(2-甲基噻吩、苯并噻吩、二苯并噻吩及噻蒽)作为稠油水热裂解的模型化合物,通过实验探究不同类型含硫有机物的水热裂解过程及铝离子的催化作用。实验研究结果表明:(1)4种模型化合物在280℃时不会发生水热裂解反应;(2)由于S原子的密度云不同,生成H2_S速率也不相同,且其由大到小的顺序为2-甲基噻吩>苯并噻吩>二苯并噻吩>噻蒽;(3)Al 3+对模型化合物具有催化作用。最后,探讨了4种模型化合物的水热裂解途径。结果表明:H2_S主要由二次水解产生;在含氧条件下,反应过程中醛首先被氧化为羧酸而不是水热裂解生成CO。

During the thermal enhanced oil recovery(EOR)process,the existence of H 2S among the produced gase brings great trouble to petroleum exploration and development.Four model compounds of heavy oil(2-methylthiophene,BBT,DBT,and thianthrene)were carried out to study the pyrolysis process of different types of sulfur containing organic compounds and the catalysis of aluminum ions.The results showed that the pyrolysis reaction of 2-methylthiophene,benzothiophene,dibenzothiophene and thianthrene wouldn’t occur under the reaction temperature of 280℃.Due to the different electron cloud density of the S atom,the production of H 2S is in order of 2-methylthiophene>benzothiophene>dibenzothiophene>thianthrene.Al 3+had a catalytic effect on the model compound.The aquathermolysis path of four kinds of model compounds was discussed.The results indicated that the secondary hydrolysis plays an important role in the process of generating H 2S by aquthermolysis.In the presence of oxygen,aldehydes were first oxidized to carboxylic acids instead of generating CO by aquathermolysis.