| 摘要 |
PURPOSE:To efficiently remove an unsaturated compound, especially 1,1- dichloroethylene in 1,1-dichloro-1-fluoroethane useful as refrigerants, propellants, foaming agents and solvents by selectively hydrogenating the aforementioned unsaturated compound. CONSTITUTION:1,1-Dichloro-1-fluoroethane (HFC-141b) containing an unsaturated compound, especially 1,1-dichloroethylene as an impurity is reacted with hydrogen in an amount of preferably 1-200mol based on 1mol aforementioned unsaturated compound in the presence of a hydrogenation catalyst, preferably a platinum catalyst supported on a carrier such as preferably active carbon, alumina or silica get, normally at 50-300 deg.C, preferably 70-150 deg.C temperature to selectively hydrogenate the above-mentioned impurity present normally at 50-150ppm concentration in the aforementioned compound without reducing the HFC-141b. Furthermore, the hydrogenated substance, as necessary, is removed by rectification to reduce the above-mentioned impurity in the HFC-141b. |
