| 摘要 |
Hydrogenation and dehydrogenation reactions are effected in the presence of a Cu, Cr catalyst prepared by treating an aqueous Cu salt solution with an alkaline reagent to precipitate a copper compound, washing and drying the precipitate, impregnating it with a solution of an alkali metal chromate or dichromate and reducing the copper compound with hydrogen without previous calcination. The reactions described include dehydrogenation of primary and secondary alcohols to aldehydes and ketones respectively and the reverse reaction as an example of the catalyst's hydrogenation power. Further reactions described are hydrogenation of unsaturated aldehydes and ketones to the corresponding saturated alcohols e.g. furfural to furfuryl alcohol. Examples describe (1) the dehydrogenation of ethanol principally to acetaldehyde but with the formation of small amounts of acetic acid, ethyl acetate, ether, acetone and methyl, ethyl ketone (2) the dehydrogenation of isopropanol to acetone in which a little mesityl oxide and ethane is formed; (4) n-butanol to n-butyraldehyde and small amounts of acid, ester and hydrocarbon; (5) the hydrogenation of 2-ethyl hexenal to 2-ethyl hexanol and a little 2-ethyl hexanal; (6) n-butanal to n-butanol almost quantitatively; (7) furfural to furfuryl alcohol; (8) dehydrogenation of C12- 14 alcohols to the corresponding carbonylic compounds; and (9) hydrogenation of mesityl oxide into methyl isobutyl carbinol.ALSO:Hydrogenation / dehydrogenation catalysts are made by treating an aqueous copper salt solution with an alkaline reagent to precipitate a copper compound, washing and drying the precipitate, impregnating it with a solution of an alkali metal chromate or dichromate and reducing the copper compound with hydrogen without previous calcination. If desired the catalyst may be supported on Kieselguhr or SiO2 by inclusion thereof as a suspension in the intial copper salt solution. |
