GB625453A - Improvements in or relating to the production of sodium methoxide - Google Patents

Abstract

Solid sodium methoxide substantially free from methanol is obtained by heating the sodium methoxide monoalcoholate of methanol to a temperature above 128 DEG C., but below the charring temperature of sodium methoxide at atmospheric pressure in the absence of air or oxygen. Sodium methoxide is said to char at about 300 DEG C. or on prolonged exposure to high temperatures at about 250 DEG C. A methanol solution of sodium methoxide may be contacted with a heated metal surface as by passing a charge, which should be equivalent to about one-third of the total capacity of the vessel, into a closed heated vessel provided with agitation means so that the product is obtained in a discrete form or by revolving an internally heated drum therethrough in an enclosed system, the methoxide separating on the drum being removed by means of a doctor blade. Both these processes are performed in an inert atmosphere by passing through an inert gas, e.g. argon or nitrogen which also serves to remove liberated methanol. Alternatively, the above solution may be subjected to flash evaporation by contact with a heated inert high boiling liquid, e.g. xylene or decahydronaphthalene. An example is given of the first of the above processes and drying times of three and four hours are used at temperatures of 170 DEG and 160 DEG C. respectively.