Purification of butanediol

摘要

In a process for purifying technical butanediol-1, 4 technical butanediol is submitted to purification by treatment with a purifying agent selected from the group consisting of acid treated solid adsorbents and organic solvents substantially insoluble therein of the class of aromatic hydrocarbon solvents, chlorobenzene and carbon tetrachloride, separating said purifying agent from said butanediol and thereafter vacuum distilling the thus treated butanediol. In examples: Technical butane diol 1 : 4 obtained by vacuum distillation of the product obtained on catalytic hydrogenation of aqueous butynediol is agitated at elevated temperature with acid treated activated carbon and is then filtered and distilled under reduced pressure (I) or is extracted with benzene and distilled under reduced pressure (II). Other adsorbents mentioned are acid treated silica gel, fuller's earth and similar solid adsorbents and other solvents mentioned are toluene and xylene. The colours formed on adding concentrated hydrochloric acid to each of the products, and to butanediol-1, 4 which has been subjected to vacuum distillation only, extraction with benzene only or treatment with activated charcoal only are compared.