| 摘要 |
536,422. Aliphatic acids. DU PONT DE NEMOURS & CO., E. I., and LODER, D. J. Sept. 11, 1939, No. 25538. [Class 2 (iii)] Propionic acid and its higher homologues and their esters are made by re-acting carbon monoxide with ethyl or. higher alcohols in the presence of boron fluoride and water at 125 - 180‹C. and above 25 and preferably 500-1,000, atmospheres pressure. Instead of an alcohol there may be used an ester of such alcohol such as ethyl propionate or a body such as ether or ethyl chloride which on hydrolysis yields the alcohol; and instead of boron fluoride there may be used any of the acids produced by the action of hydrofluoric acid in boric acid or anhydride ; hydrofluoric acid also may be present. Examples describe the production of propionic acid (accompanied in some cases. by ethyl propionate) from ethyl alcohol and diethyl ether, boron fluoride and water being used as the catalyst ; pressures up to 900 atmospheres are mentioned. Specification 483,577 is referred to. Reference has been directed by the Comptroller to Specification 503,947. |
