【摘要】 研究麦草烧碱蒽醌法制浆黑液中的木素随pH值、温度、金属离子、表面活性剂等相关参数变化时的溶解情况。结果表明:麦草浆烧碱蒽醌法制浆黑液中的溶解木素在pH低于7时会大量沉淀;在温度高于70℃时,木素的溶解性良好;表面活性剂对木素的溶解有促进作用;钙、铁等金属离子能使黑液中木素微细颗粒絮聚成更大颗粒,降低木素的溶解度;Fe³⁺和Al³⁺对黑液中木素的絮聚作用大于Ca²⁺,Zn²⁺。基于以上研究结果可知,在对纸浆洗涤时应避免上述金属离子的引入,且采用热稀碱液洗涤时对于洗浆效果会有一定提升作用;适当加入表面活性剂有利于木素的洗出。更多还原

【Abstract】 The effects of pH, temperature, metal ions, and surfactants, etc., on the dissolution behaviors of lignin in NaOH-AQ pulping liquor of wheat straw have been investigated deeply. The results showed that with the pH of black liquor decrease to 7, the dissolved lignin would precipitate largely; and with the temperature holding at a high value（>70℃）, the lignin showed a good solubility. Besides, adding surfactants into the black liquor is good for dissolution of lignin. The metal ions existed in the black liquor(e.g., Ca²⁺, Fe³⁺, Al³⁺, Zn²⁺, etc.) can make the lignin coagulation. Based on the above results, it can be known that during pulp washing process, it should be avoided to introduce the above metal ions. And using hot caustic liquor and adding a suitable amount of surfactants into pulp washing process is good for separation of dissolved lignin from pulps.更多还原