GB363948A - Improvements in or relating to the manufacture of alkali metal acetates - Google Patents

Abstract

Hydrogen is produced by the action of acetylene and steam on alkali hydroxide.ALSO:Alkali metal acetates are obtained by the action of acetylene and water on alkali metal hydroxides at a moderately elevated temperature and at atmospheric or elevated pressure, from 1-4 molecular proportions of water being used with each molecular proportion of acetylene. The water may be introduced as vapour, liquid, or alkali solution, and the acetylene may be diluted with indifferent gases such as hydrogen, nitrogen, methane, or other gaseous hydrocarbons. Using sodium hydroxide, temperatures between 275-325 DEG C. should be employed, while temperatures between 200-350 DEG C. may be employed when potassium hydroxide is used. The reaction may be carried out with a fused or a solid, comminuted reaction mixture. With sodium hydroxide, it is preferred to allow the reaction to proceed until two-thirds of the alkali is converted to acetate, whereupon the product is dissolved in water, the acetate crystallized out, and the excess of hydroxide reconcentrated and returned to the process; this mode of operation may also be continuous. A mixture of sodium hydroxide and potassium hydroxide may be used in any desired proportion and, conveniently, in the liquid state. In this case, the acetate may be recovered solely as sodium acetate by adding sodium hydroxide to the dissolved reaction product, or by stopping the reaction when the amount of acetate formed is equivalent to the sodium hydroxide taken, and then crystallizing from water. Examples are given. Hydrogen produced by the process may be recovered for use elsewhere. The Specification refers to the production of acetates (a) by the action of acetylene on anhydrous alkalies, and (b) by the action of diluted acetylene under pressure on dilute aqueous alkalies.