GB621749A - Improvements in and relating to catalysts and their use - Google Patents

Abstract

A copper-containing catalyst is prepared by treating a copper aluminium alloy containing copper and aluminium in the relative proportions by weight respectively of from 40 : 60 to 75 : 25 with an aqueous alkaline solution, other than of an alkali metal sulphide or polysulphide, so as to remove a portion at least of the aluminium from the surface layers. The alkaline solution is preferably that of an alkali metal hydroxide or carbonate. The alloy is preferably a fine-grained one prepared by chill casting, and is crushed and graded (the grading preferably being 1/8 -\ba1/4 inch) before the treatment. 1 per cent to 70 per cent of the aluminium may be removed by the treatment. It is preferable to increase the concentration of the alkali solution as the treatment proceeds. The catalyst may be used in the alkalised form or, alternatively, may be washed with water until free from alkali.ALSO:1,-5 Pentanediol is prepared by the reaction of dihydropyran with hydrogen and water in an autoclave at 200 DEG C. and pressures ranging from 250-150 atmospheres in the presence of a granular foraminate copper catalyst prepared by treating a granular copper-aluminium alloy with aqueous sodium hydroxide to remove a proportion of the aluminium. Acetone is prepared by passing iso-propanol vapour through the glass tube of an electric tubular furnace heated to 300 DEG C., which is charged with a copper catalyst prepared by treating a granular copper-aluminium alloy with aqueous sodium hydroxide to remove a proportion of the aluminium, preferably followed by washing with water to remove the alkali.