| 摘要 |
1481895 Preparation of glycol ethers HOECHST AG 7 Feb 1975 [9 Feb 1974] 5325/75 Heading C2C Glycol ethers are produced by reacting ethylene oxide with a C 1 -C 4 straight or branched chain alcohol in the liquid phase at superatmospheric pressure and a temperature of up to 120‹ C. in a first step in the presence of a solid catalyst, either the catalyst and reaction mixture being circulated or the catalyst being fixed and the reaction mixture circulated, the reaction being completed in a second step either in the presence of the same solid acid catalyst at up to 120‹ C. or in the presence of an alkali at up to 200‹ C. The solid catalyst is for example aluminium hydrosilicate (preferably montmorillonite), silica gel or an acidic ion exchanger. The major product is the monoether of ethylene glycol, with minor amounts of polyglycol ethers, the alcohol: ethylene oxide ratio in the feed being in the range 5.5 : 1 to 11 : 1, the temperature in the main reactor 100‹ C. and the pressure 20 atm. Various reactor layouts are described where the catalyst is either completely circulated with the reaction mixture, circulated in part with the mixture, or is in a fixed bed. |
