硫酸盐竹浆光催化漂白中部分影响因素的探讨

Some Factors Affecting Photocatalysis Bleaching of Bamboo KP

利用自制光催化漂白反应器,对竹浆光催化漂白过程的部分影响因素进行了研究。实验结果表明光催化漂白8h后,NaOH用量3%的漂后浆白度比NaOH用量1%的可提高12.4%ISO,但粘度下降67mL/g,显示纸浆光催化漂白过程中控制合理的碱性条件非常重要;与传统的纸浆漂白方式相比,纸浆光催化漂白反应受温度的影响较小,即使在低温(13℃)条件下,纸浆光催化漂白后浆料白度也可以达到81%ISO;另外,浆浓对纸浆光催化漂白反应有较大影响,在光源不变的情况下,随着浆浓的增加,参与光化学反应的纸浆比例相应减少,从而导致漂后浆白度降低。

Photocatalysis bleaching is a new type of environmently friendly bleaching. In this paper, some factors affecting photocatalysis bleaching of bamboo KP were studied in a pulp photocatalysis bleaching reactors. The results showed: after 8 hours photocatalysis bleaching, the brightness of the bleached pulp with using 3% NaOH dosage was 12%ISO higher than the bleached pulp with using 1% NaOH dosage, but the viscosity dropped 67 mL/g, it indicated that alkaline environment was very important in photocatalysis bleaching and had a significant influence on bleaching time. Modest alkaline condition was helpful to obtain high brightness, but too much alkali charge would lead to badly degradation of carbohydrate and great loss of pulp viscosity; in contrast to conventional pulp bleaching, temperature had less effect on the results of photocatalysis bleaching, 81%ISO brightness could be obtained after 8 hours photo-bleaching even at a lower temperature (13°C). In addition, pulp consistency had a visible effect on the result of photocatalysis bleaching, at constant light source condition, the brightness of the bleached pulp decreased as the pulp consistency increased.