【作者】 宋海农；

【导师】 陈中豪； 王双飞；

【作者基本信息】 华南理工大学 ， 制浆造纸工程， 2004， 博士

【摘要】 我国拥有丰富的竹子资源，因地制宜的大力发展竹浆产业化，是解决我国原料供需矛盾的有效途径。传统的纸浆含氯漂白方式给环境带来了严重的污染问题，有针对性地研究开发环境友好的竹浆漂白新技术，有利于推进竹浆产业化，对实现我国造纸工业的可持续发展具有重大的意义。 本论文采用自行设计和制作的纸浆光催化漂白反应器，以中压汞灯作为紫外光源，采用浸入式反应形式，在常压条件下对竹子硫酸盐浆进行光催化漂白。首先研究其漂白工艺和影响因素，并与传统含氯漂白进行了对比，结果表明：与传统漂白方式有较大不同，纸浆光催化漂白过程中起关键作用的影响因素有：光照射方式对纸浆的光催化漂白有着至关重要的影响，纸浆的光催化漂白符合光化学的“格罗塞．德雷帕定律”；反应体系中必须有氧气的参与，而且氧气是影响后继脱木素程度和纸浆白度的关键因素之一；在光催化漂白中控制合适的碱性条件非常重要的，并对漂白时间有着直接的影响，适当的碱性环境可以促进反应顺利进行并获得高白度的纸浆，又可在漂白终点保持较高的粘度，过高的用碱量会导致纤维素的严重降解。此外，光催化漂白反应受温度的影响比传统的漂白方式小，即使在低温（13℃）下，经过8小时的漂白也可以获得81％（ISO）的白度，随温度的升高，纸浆漂后的白度有所增加。在光源和其他反应条件不变的情况下，纸浆光催化漂白表现出宏观上的“反应器尺寸效应”，反应器尺寸越大，漂白浆层越厚，则漂后浆白度越低。在光源不变的条件下，随着浆浓的增加，漂后浆的白度下降，木素脱除率减少。 通过对4种不同的光敏剂（玫瑰红、亚甲基蓝、曙红、吖啶橙）的漂白效果进行了评价，发现玫瑰红的漂白效果最好。与含氯的C-E-H三段漂和（C+D）-E／O-H-D多段漂对比发现，竹浆光催化漂白的白度和粘度介于2种含氯漂白之间，但漂后浆的白度稳定性以及得率较高。而且，光催化漂白产生的废水量较少，污染负荷也较低，表明光催化漂白是一种环境友好的清洁化漂白新技术，具有潜在的应用前景。 本文进行了光催化漂白中减少碳水化合物降解的研究，并与H₂O₂进行了协同和组合漂白的初步探讨，发现光催化漂白中EDTA络合与1％NaNO₂溶液屏蔽的协同作用能在保持较高白度的同时，有效的减少碳水化合物的降解。在光催化条件下的H₂O₂漂白中，大量的H₂O₂发生无效分解，漂后浆的白度增值有限。漂白时间相同的情况下，与单段光催化漂白相比，光催化漂白与常规H₂O₂漂白的两段组合漂白有利于提高漂后竹浆的白度和粘度。 对竹浆光催化漂白反应历程和脱木素动力学的初步研究表明，光催化漂白过更多还原

【Abstract】 There are abundant bamboo resources in China. Developing the bamboo pulp industrialization according with the local conditions, what is an available way to solve the shortage of fiber material for papermaking. Due to conventional bleaching technology with chlorine containing agents bring severe pollution on environment, especially bleaching effluent, it is necessary to look for a new environment friendly bleaching technology for bamboo pulp, and it is beneficial to promote bamboo pulp industrialization. Furthermore, it is significant to the sustainable development of Chinese paper-making industry.In this study, a series of pulp photocatalysis bleaching reactors were designed and made firstly. In those reactors, mercury lamp with a quartz glass cooler, as a ultraviolet light resource, was immerged into the reactor, photocatalysis bleaching of the bamboo kraft pulp were operated at atmospheric pressure in these reacrors. First of all, the technology and influence factor of photocatalysis bleaching were studied, and compared with conventional bleaching technology, which contained chlorine agents were performed. The results showed that there were many of difference between photocatalysis bleaching with conventional bleaching methods. There were several key effects during photocatalysis bleaching for pulp: irradiation mode was the first key effect, photocatalysis bleaching accorded with Grotthus-Drapper Law in photochemistry; oxygen was another key effect, delignification and improving brightness could not keep on without oxygen in system; alkaline condition was very important and had a directly effect on bleaching time, modest alkaline condition was helpful to obtain high brightness with a good pulp viscosity, but too much alkali dosage would lead to badly degradation of carbohydrate and big loss in pulp viscosity. Moreover, temperature had less effect on result of photocatalysis bleaching than conventional bleaching, even at a lower temperature(13 ℃ ), 81%(ISO) brightness could be obtained after 8 hours photo-bleaching, the brightness would improve with higher temperature. Pulp photocatalysis bleaching had a special and macroscopical "Reactor Dimension Effect" when the light source and other parameters were invariant, the bigger dimension of reactor, the thicker pulp layer, the lower brightness was obtained. At constant light resource condition, the more consistency increasing, the lower brightness was obtained, the less content of lignin更多还原