木质素磺酸盐的膜法提纯及分级

研究利用微滤除杂+陶瓷膜酸化除盐+多级超滤工艺提纯分级木质素磺酸钠,该工艺离子去除率高,Ca~(2+)含量由90.41 mg/L降至15.53mg/L, Mg~(2+)含量由96.24mg/L降至11.77mg/L, SO_4~(2-)含量由6667.9mg/L降至224.07mg/L,离子去除率分别为82.82%, 87.77%, 96.64%,木质素磺酸钠纯度由53.42%提高到95.10%。分子量测试证实了膜法分级木质素磺酸钠的有效性,各级分产品红外光谱存在差异。该提纯分级工艺满足了高端应用中对纯度、活性、分散度的要求,工业上可因应用需求选择不同级别的级分,提升了其工业实用价值。     

木质素系水处理剂的研究近况及进展

提出了我国碱木质素利用关键是增加碱木质素醇羟基和酚羟基含量,降低甲氧基含量,提高反应活性.分析了采用化学和物理等方法增加碱木质素自身的反应活性的原理和可能性.介绍了木质素系水处理剂的研究近况,对于我国木质素水处理剂应用研究存在的产品功能单一等问题,认为应根据我国工业木质素来源特点,先采用多种手段提高碱木质素的反应活性,然后研制多功能水处理剂,可充分发挥木质素自身优势,具有较大发展前景.     

木质素/聚癸二酸丙三醇酯弹性体制备与形状记忆效应研究

以甲醇为溶剂,对碱木质素进行分级分离,并利用分级后的碱木质素、癸二酸与丙三醇为原料,采用"一锅两步法"制备了木质素/聚癸二酸丙三醇酯弹性体。利用红外光谱、热重分析等方法对分级后碱木质素的化学结构与热稳定性进行了表征,研究结果表明,分级后的碱木质素化学结构与未分级碱木质素相似,具有较小的缩合指数,为0.786;第二失重阶段的起始温度低于未分级碱木质素,为220℃。并考察了反应时间对木质素/聚癸二酸丙三醇酯弹性体的玻璃化转变温度与交联密度的影响。研究结果表明,延长反应时间能够提高所制备弹性体的玻璃化转变温度和交联密度。对所制备材料的形状记忆性能进行分析,结果表明,材料具有较好的形状记忆效应,形状固定率为96.85%,形状恢复率为99.75%。     

木质素改性沥青的制备及性能初探

化学制浆过程产生的工业木质素是重要的化工原料,广泛应用于材料、石油、建筑、农林等领域。本文探讨了松木硫酸盐木质素对沥青性能的影响,采用红外、热重、差示扫描量热、光学显微镜等手段表征了木质素改性沥青的性能。结果显示,木质素在沥青中分布均匀,相容性较好,属于物理混合,木质素的掺加可降低改性沥青的温度敏感性,改善高温稳定性,低温抗裂性未受影响,同时抗老化性能也得到提高。木质素在改性沥青中的添加量可达20%,具有良好的应用前景。     

木质素磺酸盐对80%烯酰吗啉WG的性能影响

研究了国内外不同厂家的20种木质素磺酸盐对80%烯酰吗啉WG应用性能的影响.国外产品的分散性能普遍好于国内产品,其中Meadwsetvaco公司VSI-D80作为分散剂时,悬浮率达到98.42%.同内产品中石岘造纸厂和广州造纸厂生产的木质素磺酸钠能使WG的悬浮率达到近90%.进一步研究了不同分子质量的石岘木钙对烯酰吗啉WG性能影响,发现分子质量大于1万的石岘木钙级分有利于提高WG悬浮率和崩解性,分子质量是影响WG性能的主要凶素.不同阳离子木质素磺酸盐对WG的性能影响不大.通过测定延长静置时间后水分散粒剂的悬浮率变化,可以反映悬浮液的分散稳定性,以Kinsperse 126作为分散剂的WG分散稳定性优于石岘木钠的.     

含木质素基混凝土外加剂的研究进展

综述了木质素在混凝土外加剂中的应用。工业木质素,尤其是木质素磺酸盐,可以充当混凝土减水剂、缓凝剂、引气剂和泵送剂。由于未经改性的工业木质素性能不够理想,为了提高木质素基混凝土添加剂的性能,宜对其进行适当的改性。碱木质素经过氧化、磺化、磺甲基化、接枝共聚等改性后,可以得到具有良好性能的混凝土外加剂。     

造纸黑液制取水煤浆添加剂性能研究

0前言碱法制浆废液(黑液)中木质素含量约为黑液中固形物含量的20%～30%，并且大部分是以碱木质素的形式存在。一般黑液中有效碱含量1．14%，碱木质素完全溶于黑液中，呈亲水胶体，因而不发生沉淀。碱木质素胶体有带电的核和溶剂化外壳，构成亲水基团。由于碱木质素亲水基团的存在，使黑液具有一定的表面活性。但由于碱木质素亲水胶体基团易被破坏，所以黑液的表面活性不太稳定。因此要利用黑液生产水煤浆添加剂必须在碱木质素中引入碘酸基、氨基、羧基等阴离子表面活性基团，进行改性，利用黑液制取水煤浆添加剂主要是在木质素分子的烯醇…     

工业木质素的改性及其作为精细化工产品的研究进展

随着社会的发展,人类正面临着资源消耗过度、环境污染加剧的困境。积极寻找可再生资源,采用绿色化学工艺、减少环境污染是人类社会可持续发展的必然选择。木质素是自然界第二丰富的生物质可再生资源,工业木质素是制浆造纸的副产品,目前回收利用率不高,大部分随废水排放,既污染环境,又浪费资源。工业木质素的资源化利用具有重大的经济、社会与环境效益。实现工业木质素的资源生态化利用,必须考虑市场对产品的需求、产品的性能价格比、生产工艺的绿色化及发挥工业木质素本身的特性等四方面的因素。技术创新是保证实现工业木质素资源生态化利用最重要的条件。工业木质素通过改性后作为混凝土减水剂、水处理剂、水煤浆分散剂等方面的研究与应用已取得良好进展,是工业木质素资源生态化利用的成功例子。     

高密度聚乙烯溶液分级和结晶性能研究

采用逐步降温和控制沉淀剂用量的方法对HDPE进行溶液分级，以期制备具有特定结晶度的PE标准物质。在特定的分级工艺下，级分2结晶度的均值和扩展不确定度分别为79．34％和0．45％。同时采用GPC、FTIR和DSC对级分的摩尔质量、支化度和结晶性能进行了测定和分析，结果表明溶液分级能够将HDPE分成窄摩尔质量分布且具有特定结晶度的级分。在本研究范围内，在同样热历史和降温速率条件下，摩尔质量从高到低、支化度由大到小的级分非等温结晶能力依次增强，形成晶体的有序度逐渐增大。较低摩尔质量且支化度小的窄摩尔质量分布级分具有较完善、分布更加均匀的薄片晶结构。     

粒度级配对新疆低阶煤成浆性影响的研究

针对传统制浆工艺所制煤浆质量分数偏低,不利于后续气化反应的问题,以两种新疆低阶煤为原料,采用国家水煤浆工程技术研究中心自主研发的分级研磨制浆工艺技术,考察了粒度级配对新疆低阶煤成浆性的影响。结果表明:两种煤采用分级研磨制浆工艺后,煤浆粒度0.075 mm的粒级质量分数较传统制浆工艺均提高了13%左右,煤浆最高质量分数较传统工艺分别提高了3.14%、3.12%,煤浆流动性及稳定性有较大改善。     

Molar mass-dependent profiles of functional groups and carbohydrates in kraft lignin

Technical lignins are complex, irregular, polyphenolic compounds obtained in large quantities as by-products of the pulp and paper industries or according to current biorefinery setups. The availability of kraft lignin is increasing due to larger scale retrieval from process liquors, which opens new possibilities for further refining or new applications of such lignins. In the present study, sequential ultrafiltration of kraft lignin was performed to fractionate the lignin and to elucidate molar mass-dependent changes in lignin structure. Two industrial black liquors and three precipitated lignins were fractionated, and their functional groups were determined, providing molar mass-dependent profiles. Interrelations between structural parameters and functional groups, the molecular weight ranges, and the different lignin sources are discussed. This will help to establish structure-property-application relationships (SPARs) for technical lignins which are required for any future large-scale application.     

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.     

木质素抗氧化性研究

采用DPPH法对浓度范围为50~500μg/mL七组浓度下的木质素磺酸钠水溶液和浓度范围为50~300μg/mL六组浓度下的碱木质素水溶液的抗氧化性进行了研究,绘制了两种木质素与DPPH的反应动力学曲线。研究结果表明:浓度为400μg/mL的木质素磺酸钠与其他浓度的木质素磺酸钠水溶液相比,对DPPH清除能力最强,反应终止时,对DPPH的清除率达97.4%;浓度为200μg/mL和250μg/mL的碱木质素对DPPH的清除能力相当,且高于其他浓度,反应终止时,对DPPH的清除率分别为93.9%和94.6%。     

红麻硫酸盐法蒸煮中溶出木素的分子量分布及变化

采用凝胶色谱法（GPC）对红麻皮和秆芯硫酸盐法蒸煮过程中溶出木素的分子量及其分布的变化进行了研究。结果表明，随着蒸煮的进行，红麻皮和秆芯溶出木素的平均分子量逐渐增大，多分散性和特性粘数也相应增大。此外，在同一蒸煮条件下，红麻秆芯溶出木素的平均分子量高于红麻皮，这也说明了红麻秆芯比红麻皮更难脱木素。研究还发现，红麻原料木素以及溶出木素的分子量分布曲线都呈单峰现象。     

硫化钠预处理制浆残余木质素的化学结构特性

用化学和波谱分析研究了硫化钠预处理硫酸盐制浆中残余木质素的化学结构特性。结果表明 ,硫化钠处理能促进硫与木片中木质素的结合 ,而甲氧基的含量有所下降。与对照硫酸盐制浆相比 ,预处理条件下木质素的缩合程度较低 ,经过蒸煮后残余木质素的缩合程度有较大的提高。     

木质素结构及热解特性

为研究结构类型和提取方法对木质素热解特性的影响,本研究采用Klason方法预处理得到的棉杆、核桃壳Klason木质素和贝克曼方法预处理得到的核桃壳磨木木质素（MWL）,并结合傅里叶红外光谱仪（FT-IR）和快速热解仪-气相色谱/质谱联用（Py-GC/MS）对其化学结构和热解特性进行分析。FT-IR表明碱木质素为G型木质素,棉杆木质素属于GS类型木质素,而核桃壳木质素具有 HGS木质素的特征;Py-GC/MS分析发现原料的变化以及提取方法对木质素热解产物的组成有明显的影响,在棉杆Klason木质素中邻苯二酚类产物含量为28.18%,而在核桃壳Klason和磨木木质素的含量分别为18.12%和35.11%。同时研究表明经两种方法处理的木质素结构有明显的不同,其中Klason木质素结构中苯丙酸侧链上的α-和β-醚键明显断裂,而贝克曼处理主要体现在苯基芳基醚键的断裂。     

Effect of Kraft Cooking Conditions on the Chemical Composition of the Surface and Bulk of Spruce Fibers

By varying cooking temperature, alkali charge, ionic strength, and cooking time in Kraft pulping of spruce chips, pulps ranging between kappa numbers 20–80 were obtained. The unbleached Kraft pulp fibers were subjected to mechanical peeling in order to separate the surface material from the bulk of the fibers and the carbohydrate composition and lignin content of the two fractions were analyzed. As expected, the lignin and xylan contents were higher on the fiber surface than in the fiber wall. The percentage of xylan on the fiber surface was fairly constant, independent of different pulping conditions or degree of delignification. The lignin proportion on the fiber surface gradually decreased with decreasing kappa number. At a given kappa number, pulping at a higher temperature resulted in less lignin on the fiber surface, probably because of the higher solubility of lignin at higher temperature. Cooking at lower alkali charge also resulted in lower lignin content on the fiber surface at a given kappa number. In this case, there was more time available for degradation of the surface lignin since the lower alkali charge resulted in longer cooking time needed to reach a certain kappa number.     

黑液和碱木素在石油工业中的应用

本文综述了碱法制浆黑液以及碱木素在石油工业中的应用。黑液可以直接作为低粘度稠油的驱油剂,也可作为高粘度稠油的降粘剂。与蒸汽驱或蒸汽吞吐配合使用,可显著地提高稠油的采收率。从黑液中分离出的碱木素,可用作钻井泥浆添加剂、注水或注蒸汽采油的堵水剂和调剖剂、表面活性剂驱油的牺牲剂、污水处理的絮凝剂等。在石油工业中充分利用碱法制浆黑液和碱木素,对解决黑液污染问题,降低油田化学剂成本,具有重要意义。     

Investigation of oil palm based Kraft and auto-catalyzed organosolv lignin susceptibility as a green wood adhesives

The aim of this study is to highlight the application and potentiality of oil palm based lignins in the synthesis of green phenolic resins. The delignification processes were conducted using Kraft and auto-catalyzed ethanol–water pulping processes. The extracted lignins were characterized using elemental analysis, Fourier transform-infrared, ¹H and ¹³C nuclear magnetic resonance (NMR) spectroscopy, molecular weight distribution (M_n, M_w and polydispersity), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC). The obtained FTIR results revealed that the Kraft lignin contained substantial amounts of guaiacyl units with smaller amounts of syringyl units. The molecular weight of Kraft lignin was 1564 g mol⁻¹ which is higher than organosolv lignin at 1231 g mol⁻¹. The activated free ring position (2.99%) of Kraft lignin was comparatively higher than that of organosolv lignin (2.06%) which was measured using Mannich reactivity analysis. Thermal analysis of Kraft lignin showed higher thermal stability compared to organosolv lignin. The structural and thermal characteristics implied that Kraft lignin had higher potential for the production of green phenolic resins when compared with organosolv lignin.     

木素表面活性剂的开发与应用

以工业木素为原料，可开发出多种表面活性剂产品，如染料分散剂、混凝土减水剂和加气剂、沥青乳化剂、表面活性剂采油的牺牲剂和原油乳化阵粘剂、液态燃料乳化剂等。木素表面活性剂价格低廉，有较强竞争力，开发木案表面活性剂有利于充分利用木素资源和治理纸厂制浆黑液造成的环境污染，应当加强这方面的研究工作，特别是基础研究。