Abstract:

Isolation of β-methylnaphthalene from the 230～250℃ fractions of ethylene tar was studied by using an extraction-rectification method. The quinoline compounds and indole in the ethylene tar were firstly extracted with 80% sulfuric acid，through which the extracted residue contains only trace amount of quinoline，and the amount of indole is reduced from 2.06% to 0.08%. The extracted ethylene tar was then rectified yielding β-methylnaphthalene with 96.73% purity and an yield close to 60%. Compared with the distillation，crystallization and recrystallization process，the current method provides β-methylnaphthalene with lower impurity content and higher purity.