Method for extracting dibenzofuran from absorber oil of coal tar

The present invention relates to a method for extracting oil from coal tar dibenzofuran wash. Belonging to the field of chemical separation. The present invention employs a suitable refluxing ratio of the first atmospheric distillation feedstock washing oil, taken fractions of different temperature ranges, a high oxygen content fraction into dibenzofuran fraction segment (fluorenyl oxygen-containing> 05%) with a low content of fluorene segment fraction, low levels of dibenzofuran fraction secondary rectification section taken the appropriate fractions with high content of oxygen fluorene fractions were combined, recrystallized from a certain proportion of the solvent is added to a mass of high levels of dibenzofuran fraction, for recrystallization of crude fluorene, and then subjected to a second crude fluorenyl recrystallized fine fluorene. The present invention is obtained by distillation twice the amount of oxygen-containing fluorenyl> 60% crude oxygen fluorene, dibenzofuran extraction with an organic solvent in a supercritical state, the whole process uses simple equipment, low energy consumption, easy operation, high yield; separation method is simple, there is no loss of product, solvent recovery is easy, it can be reused many times, substantially no pollution, low cost, industrial prospects.