GB354783A - Improvements in the manufacture and production of modified castor oil - Google Patents

Abstract

Castor oil alone or mixed with mineral oil is heated to above 100 DEG C. in presence of phosphoric acid and/or acid esters thereof, whereby it loses water and becomes soluble in mineral oil and on prolonged treatment acquires drying properties resembling those of linseed or tung oil. Temperatures between 150 and 350 DEG C., especially 200-260 DEG C., are suitable. Up to nearly 3 molecules of water may be removed. The solutions in mineral oil are used as lubricants, and the drying castor oil is used in the manufacture of drying artificial resins, e.g. along with polybasic carboxylic acid and polyhydric alcohols, and for or with linseed or tung oil in paints or other coating materials. Esters specified are mono- and di-butyl and mono- and di-cresyl esters. The phosphoric acid or ester may be carried by active carbon, diatomaceous earth, "Tonsil" or other bleaching earth, or other finely divided absorbing substance. In an example, a mixture of castor oil and 0,4 per cent of phosphoric monobutyl ester is heated with stirring in vacuo to 200-250 DEG C. After 2-3 hrs. 2-3 per cent of water has distilled off, and the oil is soluble in mineral oil, e.g. lubricating oil. On further heating drying properties gradually develop. The ester is removed by settling and filtration, an oil with an acid value of 2 being obtained. Or 0,3 per cent of phosphoric acid is used at 220-250 DEG C., a current of nitrogen or carbon dioxide being passed through the evacuated reaction vessel. The acid is removed at 50-70 DEG C. by about 1 per cent of calcium carbonate with or without 0,5 per cent of asbestos, fuller's earth, active carbon, or charcoal, and filtration. Specifications 24936/05, 317,391, and 321,724, [all in Class 91, Oils, &c.], are referred to.ALSO:Castor oil alone or mixed with mineral oil is heated to above 100 DEG C. in the presence of phosphoric acid and/or acid esters thereof, whereby it loses water and becomes soluble in mineral oil and on prolonged treatment acquires drying properties resembling those of linseed or tung oil. Temperatures between 150-360 DEG C., especially 200-260 DEG C. are suitable. Up to nearly 3 molecules of water may be removed. The solutions in mineral oil are used as lubricants, and the drying castor oil is used in the manufacture of drying artificial resins, e.g. along with polybasic carboxylic acid and polyhydric alcohols, and for or with linseed or tung oils in paints or other coating materials. Esters specified are mono- and di-butyl and mono- and di-cresyl esters. The phosphoric acid or ester may be carried by active carbon, diatomaceous earth, "Tonsil," or other bleaching earth, or other finely-divided absorbing substance. In an example, a mixture of castor oil and 0,4 per cent of phosphoric mono-butyl ester is heating with stirring in vacuo to 200-250 DEG C. After 2-3 hours 2-3 per cent of water has distilled off, and the oil is soluble in mineral oil, e.g. lubricating oil. On further heating drying properties gradually develop. The ester is removed by settling and filtration, an oil with an acid value of 2 being obtained. Or 0,3 per cent of phosphoric acid is used at 220-250 DEG C., a current of nitrogen or carbon dioxide being passed through the evacuated reaction vessel. The acid is removed at 50-70 DEG C. by about 1 per cent of calcium carbonate with or without 0,5 per cent of asbestos, fuller's earth, active carbon or charcoal and filtration. Specifications 24936/05, 317,391, and 321,724, [all in Class 91, Oils &c.], are referred to.