公开(公告)号：GB787755A

公开(公告)日：1957-12-18

申请号：GB1481455

申请日：1955-05-23

Applicant: STANDARD OIL CO

Inventor： BRENNAN HARRY MICHAEL ,  VANDERHAAR ROY WILLIAM ,  FIELD EDMUND

IPC: B01J21/04 ,  B01J23/40 ,  B01J23/42

Abstract: An alumina-supported platinum catalyst is prepared by adding an alkaline substance to peptized alumina in a sufficient quantity to raise the pH to between 8.5 and 12, maintaining the resulting mixture at this pH for more than one hour, separating the solid hydrous alumina, drying to a volatile content below 50 per cent by weight, impregnating with between 0.05 and 1 per cent by weight of platinum, and drying and calcining. The peptized alumina may be an alumina hydrosol prepared by hydrolysing aluminium acetate or alkoxide, by digesting hydrous alumina in dilute acid, or by the process of Specification 552,053, in which amalgamated aluminium is digested in a dilute organic acid; alternatively amalgamated aluminium may be digested omitting the organic acid, the hydrous alumina formed being separated and peptized with dilute organic acid. Suitable alkaline substances for adding to the peptized alumina are ammonium hydroxide, water-soluble amines, or quaternary ammonium hydroxides; sodium hydroxide or carbonate, potassium carbonate, or calcium hydroxide may also be used, but the alumina should then be washed free from alkali cations. The mixture may be held at the alkaline pH at 50-250 DEG F. for 1-48 hours or for longer periods, e.g. 75-150 hours. The slurry formed is filtered and the filter cake dried at up to 1200 DEG F., preferably 150-400 DEG F., for 1-24 hours. Incorporation of platinum may be effected (a) by saturation with an aqueous chloroplatinic acid solution and subsequent addition of ammonium sulphide solution; (b) by saturation with a solution of aqueous chloroplatinic acid solution containing ammonium sulphide; or (c) by impregnation with a platinum solution containing a dissolved inorganic aluminium salt, e.g. the nitrate, sulphate, chloride, bromide or iodide, and also containing an organic solvent, e.g. acetone, methanol, ethanol or isopropyl alcohol or other wetting agent, e.g. sodium benzenesulphonate, a polyethylene glycol, or a glycol ether. The catalyst is finally dried and calcined at 800-1200 DEG F. in air, hydrogen, nitrogen or flue gas; it may be in the form of a powder, irregular fragments, or shaped bodies, e.g pellets. The alumina in the final catalyst contains from 5-100 per cent of eta-alumina. Examples 1-10 describe the preparation of catalysts and Examples (1) and (8) also describe hydrocarbon hydroforming tests for measuring the activity of the catalysts. Example (1) refers to regeneration of the catalyst by treatment at 850 DEG F. and 300 lb. per sq. in. gauge pressure with nitrogen containing 2 per cent oxygen and 0.5 per cent water, and then with air containing 0.5 per cent water at 1050 DEG F. In addition to hydroforming, the catalysts are useful in other hydrocarbon conversion reactions, e.g. reforming, isomerization, hydrogenation, hydrocracking, dehydrogenation, oxidation, polymerization and condensation. Specification 736,632 also is referred to.