Distribution and composition of phenolic compounds in coal-based liquid production

The composition and distribution of phenolic compounds in five kinds of coal derived oils in coal-based liq- uid production from the different process of coal chemical industry were investigated. Firstly,the fractions were isolated from different coal derived oils by distillation in 170-210 ℃ ,which is rich in phenols. The method of acid and alkali was used to extract the phenolic compounds in 170-210 ℃ fractions. Secondly,the rich phenolic compounds were pre- treated by silicon ether derivatization,and the characterization of phenols was analyzed by GC / MS. It was found that three types of phenolic compounds,such as alkyl phenols,hydroquinones and indanol,were in each phenol-rich oil fractions from different coal derived oils,in which alkyl phenols is above 90% . There were three types of phenolic compounds,such as alkyl phenols,hydroquinones and indanol in the No. 4 CDO,in which alkylphenol contributed the 92. 4% of the total phenols. The lower-rank phenols accounted for 86. 1% of the total phenols,while the higher-rank phenols was about 13. 9% . There were two types of phenolic compounds such as alkyl phenols and hydroquinones in the No. 2 CDO,in which alkylphenol contributed the 99. 89% of the total phenols. The lower-rank phenols accounted for 99. 5% of the total phenols,while the higher-rank phenols was only about 0. 5% . There were one types of alkyl phenols in the No. 1 CDO and No. 3 CDO. The lower-rank phenols accounted for 100% of the total phenols in the No． 1 CDO,while in No. 3 CDO,the lower-rank phenols accounted for 98. 4% of the total phenols,the higher-rank phenols was only about 1. 6% . There were two types of phenolic compounds such as alkyl phenols and indanol in the No. 5 CDO,in which alkylphenol contributed the 94. 8% of the total phenols. The lower-rank phenols accounted for 91. 6% of the total phenols,while the higher-rank phenols was about 8. 4% . Therefore,the extraction and utilization of lower-rank phenols in different coal derived oils should be paid enough attention.