摘要 |
m-Xylene is difficult to separate from o-xylene by conventional rectification or distillation because of the close proximity of their boiling points. m-Xylene can be readily separated from o-xylene by using extractive distillation in which the extractive agent is dimethylformamide; dimethylformamide and 1,4-butanediol; dimethylformamide, adiponitrile and dihexyl phthalate.
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