METHOD FOR PREPARING VINYL ACETATE Russian patent published in 2004 - IPC

FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to method for preparing vinyl acetate from ethylene, acetic acid and oxygen-containing gas. Process is carried out at increased temperature in the presence of catalytic material to yield mixture of products containing vinyl acetate, liquid by-side product containing acetic acid and water and gaseous by-side product containing carbon dioxide. Liquid by-side product is isolated from products mixture and treated for reducing water concentration in its to less 6 wt.-% but, preferably, to less 4 wt.-% and more preferably to less 3 wt.-% as measured for the total amount of acetic acid and water feeding into reactor. Treated liquid product is recovered into reactor. Treatment is carried out by rectification for removing part water and withdrawal the rectification product with reduced water content, preferably, in the amount 5 wt.-%. Water concentration in liquid by-side product can be reduced by chemical reaction with acetic anhydride. Preferably, reactor with fluidized layer is used wherein palladium is used as a catalytic material and promoter is taken among the group: gold, copper, nickel or their mixture. Invention provides optimization of temperature regimen in reactor and enhanced selectivity in formation of the end product. EFFECT: improved preparing method. 12 cl, 1 tbl, 1 dwg, 4 ex