摘要 |
<p>In a process for the prodn. of paper pulp from annual plants comprising delignification by means of a neutral soln. of Na sulphite, prior to delignification, the treated material is prehydrolysed by treatment with a very dilute acid soln. which does not have, at the concn. used, specific action on the fibre, at 120-170 deg.C, to remove by dissolution of the pectocelluloses and other cellulosic prods. of no paper value. The process allows large scale exploitation of annual plants; partic. agricultural by-prods. (cereal straw, sugar cane bagasse, maize stem) and allows these to be used as sole raw material for the prodn. of e.g. paper for newspaper.</p> |