Defibering waste moisture resistant paper to recover pulp - using cpds. of sulphuric or sulphurous acid and ammonia or amine(s)

摘要

Prepn. of paper pulp by recovering waste paper which has been treated in a known manner to increase the moisture resistance of the paper fibres is described. The waste paper is mixed with water contg. either cpds. and derivs. of sulphuric acid and ammonia also their amines and amides or cpds. and derivs. of sulphurous acid and ammonia also their amines. The mixt. is then introduced into a known installation for defibering paper having a vessel made of non- oxidisable material. The process has the advantage of not requiring special plant, having a low energy requirement, giving a pulp not requiring neutralisation and also one which requires less aluminium sulphate in sizing.