桑枝-桉木板皮混合制浆漂白特性的研究

探究了不同桑枝替代率下桑枝-桉木板皮混合硫酸盐法制浆和ODEp漂白的特性。结果表明,桑枝的化学组分与桉木板皮存在较大差异,桑枝综纤维素含量低、木素含量高、纤维长度较长；在相同制浆漂白工艺下,桑枝较桉木难漂白,其所占比例越高,纸浆的卡伯值越高、白度越低,但桑枝替代率不超过30%时,纸浆具有较好的可漂性,氧脱木素效率在40%以上,漂白浆的白度在78%以上；另外,桑枝的加入可以提高混合浆的黏度和撕裂度,但对漂白浆的抗张强度和耐破度不利。

Pulping and Bleaching Performances of Mixed Mulberry Branches-Eucalyptus Slab Raw Material

The kraft pulping and ODEp bleaching performances of mixed mulberry branches-eucalyptus slab raw material with various mulberry branches ratio were studied. The result indicated that there was relatively big difference in the chemical composition between mulberry branches and eucalyptus slab. Mulberry branches had lower content of holocellulose than eucalyptus slab, but had higher content of lignin and the longer fiber length. Under the same pulping and bleaching process conditions, mulberry branches were more difficult to be bleached compared with eucalyptus slab. Higher proportion of mulberry branches in the raw material resulted in higher Kappa number and lower brightness of the pulp. The mixed pulp had a good bleachability when the proportion of nulberry branches were lese than 30%, and the oxygen delignification rate was more than 40%, and the brightness of bleached pulp was higher than 78%. In addition, the usage of mulberry branches could improve the viscosity and the tear strength of the mixed pulp, but deteriorate the tensile strength and the burst strength.