Multivariate-parameter optimization of the alkaline peroxide mechanical pulp (APMP) process for larch (Larix gmelinii Rupr.) using Box-Behnken design

The study is aiming at the finding of optimal pulping conditions for the alkaline peroxide mechanical pulping process applied to larch in terms of brightness (% ISO) and tensile strength (TS). Based on three variables, the Box-Behnken experimental design was applied to determine the effects of the first-stage and second-stage dosages of H2O2 and the impregnation temperature on % ISO and TS. The equations based on the quadratic regression analysis were developed, which describe the response behaviors as the simultaneous functions of the selected independent variables. The best brightness achieved was 75.4% ISO under the following conditions: first-stage H2O2 3.5%, second-stage H2O2 3.54%, and impregnation temperature 81.4 degrees C. The best TS (37.2 N.m g(-1)) was found under the following conditions: first-stage H2O2 2.4%, second-stage H2O2 3.9%, and impregnation temperature 90 degrees C.