造纸黑液制取木质素磺酸盐研究

以造纸黑液为原料,从中提取木质素,在NaSO3与木质素的质量比为3∶4,反应时间4h,工作压力0.6MPa的最佳条件下,经磺化成木质素磺酸盐。开发的产品可作沥青乳化剂、絮凝剂等。此法不仅提供了一种减少造纸污水对环境污染的方法,而且表明造纸污水的回收利用在工业、建筑业上有一定的利用价值,应用前景广阔。     

SFP木质素在钻井液中的作用效能

木质素磺酸盐及其改性产品是一大类传统的钻井液稀释剂，SFP木质素是用亚硫酸盐－甲醛－蒽醌法对麦草制浆的废液生产的一种木质素磺酸盐。实验表明，SFP木质素在钻井液中有稀释、起泡及絮凝三种作用。因此，SFP木质素及其改性产品可作为钻井液稀释剂和起泡剂，也可作为处理废钻井液的絮凝剂。     

木质素磺化的研究

木质素磺酸盐是一种具有广泛用途的高分子物质,开发利用木质素磺酸盐具有很广阔的前途。对造纸黑液及酸析木质素的磺化进行了研究,得出了黑液及酸析木质素磺化的工艺条件。     

木质素作为偶联剂在橡胶中的作用

对阔叶林木质素粉末与硅烷偶联剂分别等量加入天然橡胶中的性能及用吸收硫后的木质素废液,对丁腈橡胶、丁苯橡胶、三元乙丙橡胶不同添加量的试验进行了研究。结果表明：木质素粉末具有类似硅烷偶联剂KH-590的作用,吸收硫后的木质素废液添加到橡胶中依然是一种良好的且剂。     

木质素电氧化降解的研究

研究了电氧化降解过程中木质素磺酸盐的分子结构、功能团、分子量和表面活性的变化。结果表明,电氧化过程中木质素磺酸盐中的芳环被打开,-SO3H含量和表面活性降低,-COOH含量和分子量先增加后降低。     

木质素及其模型化合物氧化裂解催化剂的研究进展

木质素是绿色可持续的再生资源,但结构复杂,是通过C-O和C-C键交织相连的大分子化合物,通过化学转化可以得到系列的高附加值的化学品。通过将转化中的催化剂类型分类,对木质素及其模型化合物氧化裂解催化剂的研究进展进行综述。     

木质素及其衍生物对重金属离子吸附性能研究进展

木质素是一种有机高分子,大量存在于木材、竹材、秸秆、草类及其它植物材料中。但由于其结构复杂,导致应用受到很大的限制。有效利用好木质素这种可再生资源已成为科研工作者研究的出发点。木质素吸附剂是近年来木质素高值化利用研究的热点。文章在简要介绍木质素的化学结构及其分子修饰基础上,对木质素及其衍生物近年来在重金属离子的吸附研究进行了综述。     

球形木质素珠体的制备及其粒径分布研究

利用反相悬浮聚合技术制备球形木质素珠体,并采用正交实验综合研究了木质素珠体研制过程中各影响因素对珠体形成和粒径分布的影响。结果表明,以自制的复合分散剂L1, 采用体积比为1∶1的变压器油与氯苯混合物作为分散相,油水相比为3∶1,搅拌速度为200 r/min,反应温度80℃左右,反应体系的酸度控制在1.5 mol/L时,反应2 h后所得到的球形木质素珠体粒径分布最均匀,粒径在0.4~0.8 mm的木质素珠体占木质素珠体总质量的83.2%。     

木质素的氢解及其合成环氧树脂探索

木质素是一种潜在的能在生产中利用的自然资源。对自制的木质素在一定的条件下。进行氢解反应,得到了羟基数量提高到约为2倍量的氢解木质素,提高了木质素的活性．使其易于和环氧氯丙烷在氢氧化钠的催化作用下发生环氧化作用。本文对木质素进行了化学改性和合成环氧树脂的探索。用红外光谱和核磁共振对改性产物和环氧树脂加以表征。     

微生物降解木质素的研究进展

木质纤维是地球上最丰富的可再生生物质资源,其三大成分之一的纤维素是生产生物基材料、生物燃料及生物基化学品的重要原料,但是木质素复杂的化学结构阻碍了木质纤维的应用。常规木质素的物理、化学及物理-化学等降解方法常需要高温、高压条件,并且易产生抑制物、造成高能耗和环境污染等问题。微生物介导的生物催化过程通常在温和条件下进行,可以降低能源投入,为木质素的利用提供了更具体、更有效的选择。传统生物降解以白腐菌等真菌为代表,存在预处理周期长、对环境适应性差等问题,而细菌繁殖迅速、环境适应能力强、易于基因操作,成为未来木质素降解菌株的潜在候选者。本文在介绍木质素化学结构的基础上,综述了近年来微生物降解木质素的研究进展,着重分析了降解木质素的微生物(真菌和细菌)、木质素降解酶(过氧化物酶和漆酶)和降解机制,以及微生物降解木质素在脂类、生物塑料、香兰素、废水处理中的应用,并对微生物降解木质素的未来发展进行了展望。     

Lignin for Bioeconomy: The Present and Future Role of Technical Lignin

Lignin, the term commonly used in literature, represents a group of heterogeneous aromatic compounds of plant origin. Protolignin or lignin in the cell wall is entirely different from the commercially available technical lignin due to changes during the delignification process. In this paper, we assess the status of lignin valorization in terms of commercial products. We start with existing knowledge of the lignin/protolignin structure in its native form and move to the technical lignin from various sources. Special attention is given to the patents and lignin-based commercial products. We observed that the technical lignin-based commercial products utilize coarse properties of the technical lignin in marketed formulations. Additionally, the general principles of polymers chemistry and self-assembly are difficult to apply in lignin-based nanotechnology, and lignin-centric investigations must be carried out. The alternate upcoming approach is to develop lignin-centric or lignin first bio-refineries for high-value applications; however, that brings its own technological challenges. The assessment of the gap between lab-scale applications and lignin-based commercial products delineates the challenges lignin nanoparticles-based technologies must meet to be a commercially viable alternative.     

木质素的微生物降解

综述了木质素微生物降解酶系及酶活性调控措施,介绍了木质素降解机制及木质素微生物降解的应用。     

Structural Characterization of Pine Kraft Lignin: BioChoice Lignin vs Indulin AT

BioChoice lignin (BCL) is a newly commercialized pine kraft lignin from Plymouth Mill of Domtar, which is precipitated from black liquor of bleachable-grade pulp. Indulin AT is a pine kraft lignin commercialized by Meadwestvaco for the past 60 years, which is precipitated from black liquor of linerboard-grade pulp. Thus, the two technical lignins are produced under quite different conditions in terms of alkali charge and pulping time/temperature. While the chemical structure of Indulin AT is well documented, that of BCL is totally unknown. In this study, chemical structures of BCL and Indulin AT are characterized using modern analytical techniques and compared with those of pine milled wood lignin (MWL) in order to elucidate the structural changes that occur during kraft pulping and the structural differences, if any, between BCL and Indulin AT. Both BCL and Indulin AT are structurally very different from the native lignin (MWL) in wood, indicating drastic structural modification during the kraft pulping process. Surprisingly, BCL and Indulin AT are structurally very similar, in spite of the fact that they are produced under different process conditions. However, there are subtle structural differences between BCL and Indulin AT. BCL has higher phenolic hydroxyl, catechol, enol ether, and stilbene contents, but lower methoxyl and β-O-4 contents. These differences are explained by the different pulping conditions under which the two technical lignins are produced.     

基于氢化断裂木质素及其模型化合物C-O键的研究进展

基于不同氢化断键模式,从催化剂类型综述了目前木质素及其模型化合物的氢化断裂C-O键研究的进展。为木质素及其模型化合物的研究提供相关的理论和实践基础。     

Purification of Biorefinery Lignin with Alcohols

After hydrothermal pretreatment and enzymatic hydrolysis of wheat straw, a slurry rich in lignin but with a high content of inorganic substances, especially silica, and residual carbohydrates is produced. This slurry was used to develop an ethanol organosolv separation method to produce silica-free lignin fractions. The addition of para toluene sulphonic acid (PTSA) and the use of two alternative long-chain alcohols, oleyl alcohol or nonylphenol, were tested. In every reaction, two lignin fractions were produced and their molecular size and elemental composition were characterized. The yield of each fraction and the change in MWD were studied as a function of temperature and solid to liquid ratio. At 100, 150, and 200°C and with the use of PTSA, high-purity lignin fractions were obtained. After lignin fractionation with nonylphenol, a liquid silica-free product with high lignin content was obtained in yields between 17 and 72%.     

Lignin for polymer and nanoparticle production: Current status and challenges

In pulp production processes, lignin is generated in large quantities as a by‐product. It is often burned to generate heat and electricity. Despite the large‐scale production of lignin, its utilization in high‐value applications has remained a challenge. Recently, the production of lignin nanoparticles (LNP) and lignin polymers has gathered attention. The potential to use LNPs as reinforcement filler, UV absorbent, antioxidant, and drug carrier has been reported, while lignin polymers might be suitable for the production of composites, hydrogels, flocculants, and coagulants. This review paper provides insights into the production and application of LNP and lignin polymers. In addition, the challenges associated with the characterization and use of these products are comprehensively reviewed.     

木质素分离研究进展

木质素是一种自然界含量丰富的天然芳香族高分子化合物,木质素及其衍生物应用范围极其广阔,因此其分离制备的研究也一直受到国内外学者的青睐,木质素分离制备方法很多,本文主要概述了碱木质素、磺酸盐木质素、有机溶剂木质素和磨木木质素等木质素的提取方法及其研究进展,并对每种方法的优缺点进行了简要的描述。     

高沸醇木质素及其衍生物对菠萝蛋白酶的吸附

通过曼尼希反应和室温相分离方法合成了高沸醇木质素胺和高沸醇木质素酚衍生物,并探讨了它们对菠萝蛋白酶的吸附特性. 结果表明,引入了胺基和酚羟基的高沸醇木质素衍生物对菠萝蛋白酶的吸附性能有很大的提高,吸附能力为HBS木质素胺>HBS木质素酚>HBS木质素,而且吸附后的菠萝蛋白酶活性仍保持在较高的水平,高沸醇木质素衍生物有望成为菠萝蛋白酶的浓缩吸附剂或固定化的载体.     

酶解木质素的分离与结构研究

采用两种方法从酶解玉米秸秆制备能源酒精的残渣中分离得到酶解木质素。根据不同的分离条件,酶解木质素的得率为20%～35%。应用UV、FT-IR、GPC和13C-NMR研究了不同分离方法的酶解木质素的结构特性。结果表明,所分离的酶解木质素分子量较小,在结构上较好地保留了各种活性基团。与木质素磺酸钙相比,酶解木质素的红外图谱中多了1700cm-1和1328cm-1峰,说明酶解木质素存在非共轭羰基作用。紫外图谱在210nm,280nm和310nm附近有峰值出现,说明其具有木质素的基本结构特征,且结构上有很大的不饱和性。由13C-NMR图谱解析可知,所提取酶解木质素为GSH型木质素,主要以β-O-4、β-5、β-1的结构存在。以氢氧化钠作为萃取剂的酶解木质素提取率比有机溶剂高。酶解木质素的有效利用将提高酶解玉米秸秆制备能源酒精的经济效益。