| Shanxi province is a heavy energy chemical industry base of China, which has the advantage of coal resources, and it is also the largest coke export base in China. In the process of coking, large amounts of coal-tar oil which contains a lot of valuable components is produced as a by-product. Gas absorber oil is one of main fractions in the process of treating coal-tar oil, and it is rich in some precious organic industrial chemicals such as beta-methylnaphthalene, alpha-methylnaphthalene, acenaphthene, fluorene, etc. With the development of fine chemical industry, the application ranges of mixed methylnaphthalene, beta-methylnaphthalene, alpha-methylnaphthalene and technicalpure acenaphthene are expanding unceasingly, and that makes the market demands increasing constantly and builds the foundation of the exploitation and utilization of gas absorber oil. Therefore, it has important significance for the economic development of ShanXi province to develop the refining technology of gas absorber oil to increase recovery rate and purity of the components.Firstly, the gas absorber oil provided by Shanxi Jin Yao Corporation was analyzed with the GC-MC to get the content of every component, and the results showed that the two maximum contents were beta-methylnaphthalene and acenaphthene. So the separation and abstraction of beta-methylnaphthalene and acenaphthene from the gas absorber oil were the main objects in the thesis. A research plan was made to abstract beta-methylnaphthalene and acenaphthene from gas absorber oil after analyzing the structures, characters, applications, current situation of separation and purification of the two stuffs.Secondly, the effects of different reflux ratios on separation efficiency of every component were studied by rectifying gas absorber oil. After comparing and analyzing the contents and mass of fractions of different temperature ranges at different reflux ratios, the concludes was get that the proper reflux ratio is 5:1, the best temperature range of methylnaphthalene fraction is 215～230℃and the best temperature range of acenaphthene fraction is 250～260℃.Thirdly, the refining of beta-methylnaphthalene and the recovery of entrainer of methylnaphthalene fraction were studied in three methods: rectifications for two times, refrigeration crystal after rectifications for two times and azeotropic rectification. Acenaphthene fraction was separated into two parts—high content fraction and low content fraction, and the high content fraction was studied by rectification and recrystallization to purify acenaphthene, the low content fraction was studied by recrystallization after rectification correspondingly, and meanwhile, the effects of recrystallization and the circulation and recovery of different solvents were investigated.The results show that: high-purity beta-methylnaphthalene and acenaphthene can not be produced by the method of rectifications for two times; high-purity beta-methylnaphthalene is available by azeotropic rectificating methylnaphthalene fraction with A or B, and the operation of azeotropy rectification is simple and the purity is high when taking B as entrainer; and high purity acenaphthene (higher than 99%) can be obtained when recrystallizating acenaphthene fraction with C, D and E respectively, and E is the best recrystallization solvent if all factors such as effect, toxicity, price, etc. taken into consideration.Compared with the current technologies, the technologies of abstracting acenaphthene and beta-methylnaphthalene from gas absorber oil obtained in this thesis have outstanding advantages, such as simple process, low energy consumption, high purity products, high recovery rates and no the three wastes, and so have industrialization prospect.
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