| 摘要 |
<p>A process for the production of 1,1-difluoroethane by the hydrofluorination of acetylene in the presence of a catalyst containing aluminium fluoride. The hydrofluorination reaction is carried out at temperatures of from 150 to 350.degree.C with a residence time of from 1 to 60 seconds. The catalyst utilized is prepared by impregnating .gamma.- or .pi.-aluminium oxide with a solution of a bismuth and a manganese salt, followed by heating to temperatures in the range from 150 to 250.degree.C, initially in a nitrogen atmosphere and then, after complete drying, with a mixture of air and increasing concentrations of hydrogen fluoride up to a 100 % hydrogen fluoride atmosphere, the completed catalyst containing 0.1 to 20 % by weight of bismuth, 0.1 to 10 % by weight of manganese, 20 to 38 % by weight of aluminium, 32 to 60 % by weight of fluorine and, for the rest, of oxygen. This process gives yields of from 96 to 98 % of the required 1,1-difluoroethane, the conversion of acetylene being almost complete. 1,1-difluoroethane is an important intermediate product for the production of vinylidene fluoride or for the production of fluorinated hydrocarbons of the type used as cooling liquids.</p> |
