Abstract:The bleachability of Hibiscus cannabines kraft pulp bleaching with sodium percarbonate (SPC) was studied. The key factors, including SPC dosage, bleaching temperature, time and active alkali charge, were investigated by orthogonal experiment. The results showed that the four factors have different effects on SPC bleaching, and the range analysis shows temperature has maximal effect on brightness and viscosity. The optimal bleaching condition could be proposed as follows: SPC charge 3%, alkali charge 1%,bleaching temperature 70℃ and time 60min. The bleaching performance of SPC is lightly better than hydrogen peroxide in OPQP and OPQDP sequences, then degradation effect on cellulose is similar, the brightness can reach to higher than 80%ISO when OPQDP bleaching sequence is employed. |