蒽醌在硫酸盐制浆中的溶解特性及对蒸煮的影响

Study of AQ Effectiveness during Kraft-AQ Pulping

研究了蒽醌 (AQ)在含木素的碱性溶液中表观“溶解”性———即AQ被分散成细微颗粒 ,并根据其质量传递机制研究了在硫酸盐蒽醌法蒸煮中蒽醌的作用效果。研究发现 ,AQ可明显“溶于”含木素的碱性溶液 ,当溶液中木素的含量达到 40g/L ,在温度 90℃时 ,AQ的溶解度达到 0 1 4g/L ,但是溶解速度较慢。在碱性溶液中 ,蒽醌细微颗粒可被木片吸附 ,吸附在木片表面上的蒽醌细微颗粒可进一步被木片中的还原基团还原 ,形成高表面浓度的、完全溶解的蒽氢醌 (AHQ) ,并渗入木片内部 ,从而加速蒸煮过程木素的溶出。

Studies of the effectiveness of AQ in kraft-AQ pulping in terms of its mechanism of mass transport were conducted. Experiments showed an apparent solubility of anthraquinone (AQ) in caustic solutions containing wood lignin, the solubility of AQ in a caustic solution containing 40 g/L dissolved lignin can be up to 0.14 g/L at 90℃. However, its “dissolution” is a slow process, even taking up to 30 minutes for complete “dissolution”. The adsorption behavior of AQ micro particles was also observed. It concluded that AQ “dissolving” and adsorption play an important role in alkaline delignification process. Some explanations for unexplained observations and suggestions are proposed.