GB191108638A - Improvements in or relating to a Process for the Economic and Industrial Utilisation of Maize Straw. - Google Patents

Abstract

8638. Dorner, B. April 7. Pulp, preparation of; materials, fibrous. Relates to a process for treating maize straw and the leaves to obtain fodder for animals and cellulose suitable for paper manufacture. The maize stems freed from the earth are cut in pieces and reduced to a fibrous state. The material is then digested for several hours with a weak (0À2 to 0À4 per cent) solution of acetic acid at a moderate pressure. The liquid is discharged, the boiler filled with concentrated lime water, and the pressure increased slightly. As the lime water is neutralized quickly, small quantities of a slightly alkaline solution, such as 0À2 per cent solution of soda or a 0À1 per cent solution of sodium hydroxide, are introduced successively until the acid solution is practically neutralized. The acid and alkaline solution thus obtained are evaporated separately to a syrup, the acetous vapours arising from the acid solution being absorbed by lime. The fibrous substance remaining in the boilers consists mainly of cellulose. The pith of the maize stems known as ' parenchim ' cellulose, which is unsuitable for paper manufacture, is removed by straining the cellulose, the former passing through the sieve or strainer with the water, leaving behind the pure cellulose for the paper manufacture. The ' parenchim ' cellulose may be separated from the water on another sieve or strainer.