Abstract
Deresination effect of cationics was evaluated in a conventional multistage refining process of sulfite pulp. The best result is obtained by the addition of lauryl trimethyl ammonium chloride (I) during the hot alkali refining of the pulp obtained from freshly-cut softwood; the resin content of refined pulp and resin removal in percentage when added in an amount of 0.1% (dry pulp basis) are 0.19 and 91.4%, respectively, and the deresination effect further increases with increased amount of (I). With other cationics, the effect is poorer than with (I), and in some cases the resin content of refined pulp is higher as compared to that from a blank run. The deresination effect is also observed by stirring softwood pulp with (I) in neutral medium at high temperature after the alkali extraction stage.
When (I) is added during the hot alkali refining of hardwood pulp, the effect is inferior to that for softwood pulp.
