【作者】 刘玉；

【导师】 詹怀宇； 陈嘉川；

【作者基本信息】 华南理工大学 ， 制浆造纸工程， 2005， 博士

【摘要】 三倍体毛白杨是我国北方采用基因技术培育出的速生阔叶木树种。它生长周期短，并且具有材质好、纤维含量高、木素含量低、白度高等优点，是比较适宜的制浆工业新原料。本论文以三倍体毛白杨为研究对象，进行了常规（KP）和深度脱木素（EMCC）硫酸盐法蒸煮，以及KP和EMCC纸浆的OQP漂白工艺和机理的研究，为利用三倍体毛白杨生产高质量的化学浆提供技术和理论依据。 对三倍体毛白杨进行KP和EMCC蒸煮研究结果表明，三倍体毛白杨易于蒸煮，并且纸浆白度和得率都比较高。在最优工艺条件下，KP纸浆卡伯值为17.4，EMCC纸浆卡伯值降低到12.3。由于蒸煮过程中碱液浓度分布比较均匀，蒸煮废液中溶出物浓度比较低，EMCC蒸煮的最高温度比KP蒸煮降低了10℃，减少了碳水化合物的降解，而木素脱除率却得到大幅度提高，且几乎没有引起纸浆强度下降。相近卡伯值时，EMCC纸浆的白度和强度均高于KP纸浆。 对KP和EMCC纸浆进行以OQP为漂序的全无氯漂白的研究，在OQP漂白最优条件下，KP纸浆和EMCC纸浆的白度均超过80％ISO，并保持较高的强度。两者相比，漂白EMCC纸浆白度和物理强度略优于漂白KP纸浆。 KP和EMCC纸浆氧脱木素研究中，主要进行了用碱量、氧压和反应温度等主要影响因素对脱木素效果的研究和分析，确定了KP和EMCC纸浆氧脱木素的最佳工艺条件。研究表明，在氧脱木素后、过氧化氢漂白前对KP和EMCC纸浆进行螯合处理是必要的。螯合处理可以有效调节纸浆中过渡金属离子的分布，提高过氧化氢漂白的作用效果。在过氧化氢漂白的研究中，主要研究了过氧化氢用量、温度和时间对漂白效果的影响，确定了KP和EMCC纸浆过氧化氢漂白的最佳工艺条件为：浆浓10％，H₂O₂用量3％，MgSO₄ 0.1％，NaOH 1.5％，温度90℃，作用时间210min。 检测了杨木原料和各阶段KP和EMCC纸浆中酸不溶木素（Klason木素）和酸溶木素（UV木素）的含量。分析了蒸煮和漂白的木素脱除率，并对KP和EMCC两个系列进行比较。归纳了木素含量与纸浆卡伯值的关系。 采用酶解-弱酸解两段法从原料木片和各阶段KP和EMCC纸浆中分离出原料木素和纸浆残余木素试样，尤其是成功地从OQP漂白纸浆中分离得到了残余木素试样。采用酸析法得到粗的黑液溶出木素试样，并利用弱酸解法进行提纯，得到较纯净的溶出木素试样。将经过与未经过弱酸解的溶出木素试样进行比较表明，经过弱酸解的木素试样，得率和纯度都较高，木素试样更具有代表性。 通过凝胶渗透色谱对所有木素试样进行木素分子量分布的研究。结果表明，KP蒸煮和OQP漂白过程中，木素平均分子量减小，其中主要发生在蒸煮和氧脱木素两个阶段；过氧化氢漂白基本没有改变木素的平均分子量。在EMCC蒸煮更多还原

【Abstract】 The Triploid of Polulus Tomentosa (or triploid of Chinese Aspen) was a newly developed fast-growing hardwood species by researchers with genetic techniques. Its growing cycle was short with good wood properties, such as looseness and softness, high cellulose and low lignin contents, high brightness etc, which made it a good fiber resource for the paper industry. In this research, the KP and EMCC pulping and OQP bleaching processes and their mechanisms of the Triploid of Polulus Tomentosa were studied, which would offer support for producing high quality chemical pulps in technology and mechanisms.The research work on KP and EMCC processes of the Triploid of Polulus Tomentosa wood chips indicated that it was suitable to be cooked and resulted in high pulp brightness and yields. In KP process, the pulps Kappa number was reduced to 17.4 at the optimal conditions. The pulp Kappa number was further reduced to 12.3 at optimal conditions in EMCC process. EMCC preceded to KP process, since the cooking temperature was reduced 10°C which prevented the degradation of carbohydrates efficiently. The delignification rate was improved evidently while almost no strength losses occurred in the pulp. Comparison between KP and EMCC pulps with similar Kappa numbers, the EMCC pulp possessed of higher brightness and strength.After the OQP bleaching at optimal conditions, the brightness of both KP and EMCC pulps could reach and pass 80%ISO and the pulps kept relatively high strength. Comparison between KP and EMCC pulps, the brightness and physical strengths of EMCC pulps were higher.In the oxygen delignification of KP and EMCC pulps, the effect of main factors such as NaOH dosage, oxygen pressure and temperature were studied and analyzed and the optimal conditions for KP and EMCC were set up.It was indicated that it was necessary to have one chelation stage after oxygen delignification and before peroxide bleaching. Chelation treatment could control the metal ion distribution in the pulp effectively. In the research work on peroxide bleaching, the effect of peroxide dosage, temperature and reaction time were studied and analyzed and the optimal conditions for bleaching KP and EMCC were set up separately. Under the optimal condition of OQP bleaching, the oxygen-delignified and bleached KP and EMCC pulps were obtained for the following study. The lignin content in wood chips, KP and EMCC pulps from above were tested by更多还原