| 摘要 |
1,161,880. Vinyl acetate. CELANESE CORP. 23 May, 1967 [25 May, 1966], No. 23779/67. Heading C2C. Vinyl acetate, contaminated with 1-4C aldehydes, is purified by mixing for 5 to 60 seconds with an aqueous solution of sodium bisulphite providing 1 to 2À5 moles of bisulphite per mole of aldehyde present, the pH being maintained at 4À2 to 6À5, and then separating the aqueous solution from the vinyl acetate. Buffering agents such as sodium bicarbonate, sodium sulphite, sodium carbonate, sodium hydroxide and mixtures thereof may be used. Vinyl acetate contaminated with aldehyde may be that prepared from ethylene, oxygen and acetic acid using a noble metal catalyst with a cupric salt. A flow-diagram illustrates the use of in-line high-speed blenders for the mixing zones. |
