改性木质素胺阳离子表面活性剂合成及其溶液聚集行为研究

发布时间：2017-12-26 16:13

本文关键词：改性木质素胺阳离子表面活性剂合成及其溶液聚集行为研究　出处：《广西民族大学》2016年硕士论文　论文类型：学位论文

【摘要】：木质素是一种储量仅次于纤维素具有立体网状结构的无规酚类高分子化合物。然而,来源于制浆造纸废液的工业木质素目前仅有6%左右(主要是木质素磺酸盐)被有效利用,绝大多数仅作为燃料烧掉而并未得到高附加值利用,造成了资源的严重浪费。随着石油资源的紧缺和环境污染问题的加剧,工业木质素的开发利用越来越受到人们的重视。因此,如何高效利用木质素已经成为世界各国竞相研究的重要课题。目前来看,国内外科研工作者关于木质素的研究重点和热点基本上都集中在化学改性制备上,对其溶液行为的研究相对较少。而木质素本身的改性和改性产物作为表面活性剂在工业中应用时,都是在溶液的环境下进行的,所以对其聚集行为的研究是十分必要的。本文以硫酸盐木质素、脱氢枞酸单己二酰胺、二乙烯三胺、甲醛为原料,通过Mannich反应合成了木质素胺阳离子表面活性剂,并对其基本物化性能及溶液聚集行为进行了相关的研究,主要研究内容如下:1.木质素胺阳离子表面活性剂的合成及表征。以木质素为主要原料,经两步Mannich反应将脱氢枞酸基亲油基团及二乙烯三胺甲基亲水基团引入到木质素当中,制得了木质素胺和脱氢枞酸改性木质素阳离子表面活性剂。2.研究了木质素胺和脱氢枞酸改性木质素阳离子表面活性剂在弱酸性水溶液中的聚集行为。采用zeta电位仪、表面张力仪、紫外分光光度计等表征技术研究了木质素胺阳离子表面活性剂在水溶液中的粒径、临界聚集浓度、表面张力、zeta电位及其无机盐、pH值对其聚集行为的影响。结果表明:(1)木质素胺在稀盐酸溶液中为带正电荷的胶体溶液,其临界聚集浓度(CAC)约为0.10 g·L-1。当浓度低于CAC时,木质素胺在溶液中主要以单分子状态存在;当浓度大于CAC时,主要以多分子聚集体的状态存在。木质素胺的zeta电位随浓度升高先快速增加到最大值随后略有降低,并随盐酸浓度的增加而降低。木质素胺表面活性剂在没有引入脱氢枞酸基团时,溶液的表面张力为44.09 mN·m-1,引入脱氢枞酸基亲油基团后为36.25 m N·m-1,表面活性明显提高。木质素胺阳离子表面活性剂在甲苯溶液中水相分离出20 mL的时间是58.3 min;起始的泡沫体积为9.8 mL,5 min后的泡沫体积为6.9 mL。(2)加入无机盐后,木质素胺溶液的表面张力值升高,溶液的zeta电位下降,稳定性能下降,木质素胺在溶液中的粒径先下降而后明显增加,甚至聚集成更大的颗粒而形成沉淀。盐对木质素胺在溶液中聚集行为的影响随着盐的种类、用量和木质素胺的浓度的不同而有所不同。溶液pH值对木质素胺聚集行为的影响趋势与无机盐相似。
[Abstract]:Lignin is a kind of random phenolic compound, which is only second to cellulose with three-dimensional reticular structure. However, only 6% of the industrial lignin derived from pulping and papermaking wastewater is mainly used for lignosulfonate. Most of them are burned as fuel only, but not high added value, resulting in a serious waste of resources. With the shortage of oil resources and the aggravation of environmental pollution, the development and utilization of industrial lignin has been paid more and more attention. Therefore, how to utilize lignin efficiently has become an important subject in the world. At present, the research focuses and hotspots of lignin research both at home and abroad are basically focused on chemical modification, and their solution behavior is relatively few. The modification and modification of lignin as surfactants in industry are all carried out in the solution environment. Therefore, it is necessary to study their aggregation behavior. In this paper, kraft lignin, dehydroabietic acid was two, three, two amide ethylene amine formaldehyde as raw material, synthesized by Mannich reaction of Lignin Amine cationic surfactants, and the properties and solution of the basic physical aggregation behavior is studied, the main contents are as follows: 1. synthesis and characterization of wood prime amine cationic surfactant. With lignin as the main raw material, through two steps of Mannich reaction from dehydroabietic acid lipophilic groups and two ethylene three methyl amine hydrophilic groups into lignin, lignin amine was prepared and dehydroabietic acid modified lignin cationic surfactant. 2. the aggregation behavior of lignin and dehydroabietic acid modified lignin cationic surfactant in weak acid aqueous solution was studied. The effects of particle size, critical aggregation concentration, surface tension, zeta potential and inorganic salts and pH values on the aggregation behavior of Lignin Amine cationic surfactants in aqueous solution were studied by Zeta potential, surface tension tester and ultraviolet spectrophotometer. The results show that: (1) the lignin amine is a colloidal solution with positive charge in dilute hydrochloric acid solution, and its critical concentration (CAC) is about 0.10 g. L-1. When the concentration is less than CAC, the lignin amine is mainly in the single molecule state in the solution; when the concentration is greater than CAC, it mainly exists in the state of polymolecular aggregates. The zeta potential of lignin amines increased rapidly to the maximum value and then decreased slightly, and decreased with the increase of hydrochloric acid concentration. The surface active agent of Lignin Amine without introducing dehydroabietic acid group, the surface tension of the solution is 44.09 mN - M-1, the introduction of hydrophobic groups from dehydroabietic acid was 36.25 after M N M-1, the surface activity was significantly increased. The aqueous phase separation time of Lignin Amine cationic surfactant in toluene solution is 20 mL, the time is 58.3 min, the initial foam volume is 9.8 mL, and the foam volume after 5 min is 6.9 mL. (2) after adding inorganic salts, the surface tension value of Lignin Amine Solution increased, the zeta potential of solution decreased, and the stability performance decreased. The particle size of Lignin Amine in the solution first decreased and then increased obviously, even aggregated into larger particles and formed precipitation. The effect of salt on the aggregation behavior of Lignin Amine in the solution varies with the variety of salt, the amount of the lignin and the concentration of Lignin Amine. The effect of pH on the aggregation behavior of lignin amines is similar to that of inorganic salts.
【学位授予单位】：广西民族大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：O647.2

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