GB416711A - Improvements relating to the preparation of contact or adsorbent substances and their application - Google Patents

Abstract

Mineral adsorbent substances containing alumina, such as bauxite, have their capacity for adsorption increased by impregnation with anhydrous aluminium sulphate by one of the following processes:--(1) treatment of the roasted or ignited substance with aluminium sulphate, followed by roasting or ignition at temperatures between 350 and 700 DEG C., say at 440 DEG C.; (2) treatment of the roasted or ignited substance with a sulphate such as iron, magnesium, or iron ammonium sulphate which by double decomposition yields aluminium sulphate together with the hydrate of the metal, the sulphate of which is used, followed by roasting or ignition; (3) treatment of the unroasted material with a solution of sulphuric acid, followed by roasting or ignition; (4) treatment of the material with sulphur trioxide or sulphur dioxide and air at say 400--600 DEG C., followed by treatment at the same temperature with steam or air. The products are adapted for refining mineral oil distillates or products in the liquid or gaseous phase for removing colour and odour and polymerizing unsaturated hydrocarbons to give a residue of lubricating oil polymers, for improving the bloom of lubricating oils, and for wax filtrations. Cracked spirit may be treated in the liquid phase with bauxite treated with ferrous sulphate and maintained at 100 DEG C., and wth bauxite treated with aluminium sulphate maintained at 200 DEG C., in which case the spirit is vaporized on passing through the bauxite. After use, and cleansing by benzine or superheated steam, the bauxite may be reactivated by re-impregnation and roasting. In examples, the treatment of cracked petroleum spirit in the vapour phase, of melted paraffin wax, and of 40 per cent benzine from residuum pressure distillate is described.