GB190408545A - Treatment of Cotton Seed Hulls to obtain Useful Products therefrom. - Google Patents

Abstract

8545. Cross, C. F. April 13. Materials, fibrous; raw materials, treating; sizes. -Relates to the treatment of cotton-seed hulls to obtain cellulose, papermaker's size, &c. The hulls are heated for 6-3 hours with a 3-5 per cent. solution of caustic soda in a digester at a pressure of 20-40 lb. The solution, pressed from the solid matter, may be used as a size in the manufacture of paper and boards, while the fibrous residue may be washed and used for making paper and solutions of cellulose. To obtain pure cellulose from this residue, it is treated with chlorine until the orangeyellow colour of the chlorinated material is uniform. It is then washed and digested at 80‹-100‹ C. with a solution containing 2 per cent. of sodium carbonate and 6 per cent. of sodium sulphite. The mass then contains two forms of cellulose having different lengths of fibre, and may be used for paper-making. Or the two forms of cellulose may be separated from one another by first breaking this material in a suitable grinding- apparatus and then passing it through a succession of tanks, or over a papermaker's sand-table &c. the shorter fibres settling quicker than the others ; or the mixture may be passed through a suitably meshed sieve on which the longer fibres are retained. The longer fibres may be used for many of the purposes to which ordinary cellulose is applied. The shorter fibred cellulose may be hydrolized and otherwise treated to obtain sugar and furfural.