摘要 |
<p>In the production of 1,1,1,2-tetrafluoroethane by reacting trichloroethylene with hydrogen fluoride, crude 1,1,1,2-tetrafluoroethane is highly purified by a method comprising subjecting the crude 1,1,1,2-tetrafluoroethane to preliminary purification to remove hydrogen chloride to a concentration of not higher than 2%, and bring the preliminarily purified 1,1,1,2-tetrafluoroethane containing one or more unsaturated impurities and hydrogen fluoride in an amount at least equimolar to the unsaturated impurities into contact with a fluorination catalyst in a vapor phase to decrease the content of the unsaturated impurities.</p> |