摘要
为研究木质素胺在稀酸水溶液中的聚集行为,采用表面张力仪、紫外分光光度仪、激光纳米粒度分析仪等方法测定了木质素胺在稀酸水溶液中的表面张力、吸光度、粒径和Zeta电位,探讨了无机盐及pH值对其聚集行为的影响。结果表明:木质素胺溶液的临界聚集质量浓度(CAC)为0.10 g·L^(-1)。当质量浓度低于CAC时,木质素胺主要以单分子形式存在;当质量浓度大于CAC时,木质素胺主要以多分子聚集体的状态存在。木质素胺的Zeta电位随质量浓度升高先快速增加到最大值37.6 m V,随后略有降低。木质素胺呈现出一定的表面活性,在10.00 g·L^(-1)时的表面张力为44.09 m N·m^(-1)。在木质素胺溶液中加无机盐后,表面张力升高,Zeta电位降低,稳定性下降,容易聚集形成更大的颗粒而发生沉淀。p H值对木质素胺溶液聚集行为的影响与无机盐的变化趋势一致。
To study the aggregation behavior of a lignin-amine aqueous solution in dilute hydrochloric acid and the influence of inorganic salts and pH on the aggregation behavior of lignin-amine, measurements of surface tension, absorbance, particle size, and Zeta potential were taken using a surface tensiometer, an ultraviolet spectrophotometer, and a Zetasizer Nano ZS lazer particle analyzer. Results showed that the critical aggregation concentration （CAC） of lignin-amine was 0.10 g＇L_1. Lignin-amine mainly existed in the form of single molecules in solution when its concentration was under the CAC and in the form of multi-molecular aggregation if the concentration was much greater than the CAC. The Zeta potential of lignin-amine increased from 18.1 mV to the maximum of 37.6 mV when the concentration of lignin-amine increased from 0.01 g·L^-1 to 2.00 g·L^-1, and then decreased to 35.8 mV when the concentration increased continuously to 10.00 g·L^-1. Lignin-amine showed a surface tension of 44.09 mN·m^-1 at a concentration of 10.00 g·L^-1. If inorganic salts were added to the solution, lignin-amine would easily aggregate into larger particles and form a precipitate. Similarly, when the pH of the solution was less than 1, lignin-amine also aggregated into larger particles and formed a precipi-tate. Thus, lignin-amine solution in dilute hydrochloric acid at pH 2 was a colloidal solution with positive charges, and its aggregation behavior was strongly effected by its concentration, Zeta potential, inorganic salts and pH in the solution. [Ch, 10 fig. 1 tab. 24 ref.]
出处
《浙江农林大学学报》
CAS
CSCD
北大核心
2017年第1期7-13,共7页
Journal of Zhejiang A&F University
基金
国家自然科学基金资助项目(31260161)
广西高校研究生联合培养基地资助项目(BYB-036)
关键词
木材科学与技术
木质素胺
临界聚集质量浓度
聚集行为
无机盐
wood science and technology
lignin-amine
critical aggregation concentration
aggregation behav-ior
inorganic salt
