阳离子聚合物对混合办公废纸浮选脱墨效果的影响

摘要

Interface and colloid characterisitics of MOW deinking pulp dispersion system were investigated.Effects of several cationic polymers ( CPAM, PAC, CS) on the Zeta potential and surface tension of this pulp dispersion system under the conditions of optimal chemical deinking process were researched.At the same time, the relations between the surface and colloid characterisific changes and flotation efficiency (brightness and residual ink particles content of the pulp) were studied.Changes of deinked pulp fibers morphology and ink particles distribution before and after changing colloidal environment were analyzed by scanning electron microscopy (SEM).The results showed that interface and colloid chemical properties can be changed by adding a small amount of cationic polymer into the deinking system.The appropriate interface and colloid at environment is conducive to the removal of ink particles.When Zeta potential is - 14.0 ～ - 12.0 mV and the surface tension is 60.0 ～ 63.0 mN/m, the brightness and ink removal efficiency of MOW deinking pulp are improved compared to the optimal conventional chemical deinking by flotation.SEM images indicated that the fiber surface becomes clearer after adding a small amount of polymers to maintain the appropriate interface and colloid chemical conditions, and the small ink particles, fines and other impurities content are also reduced.%在混合办公废纸(MOW)常规化学脱墨工艺条件下,考察了几种阳离子聚合物(CPAM、CS、PAC)对脱墨浆分散体系界面及胶体化学特性(如Zeta电位、表面张力)和浮选脱墨效果(如白度、残余油墨量)的影响,并利用扫描电子显微镜(SEM)对胶体环境改变前后脱墨浆中纤维表画形态变化与残余油墨粒子分布情况进行了分析.结果表明,在MOW脱墨分散体系中加入少量阳离子聚合物对改变体系界面及胶体化学特性有积极影响;适宜的界面及胶体化学环境有利于油墨粒子的去除;当Zeta电位在-14.0～-12.0 mV之间、表画张力在60.0～63.0 mN/m之间时,与常规化学脱墨相比,脱墨浆白度及油墨去除率均有提高.SEM图显示出加入少量阳离子聚合物可保持适宜的界面及胶体化学环境,有助于进一步去除细小油墨粒子,降低细小纤维及杂质含量,使纤维表面变得更加洁净.