琥珀酰壳聚糖的合成及絮凝性能研究

Synthesis and Flocculation Properties of Succinyl-Chitosan

摘要:

壳聚糖与苯甲醛形成席夫碱（B-CTS）保护氨基，然后与丁二酸酐反应合成琥珀酰壳聚糖（SACTS）。采用FTIR、1HNMR、XRD、ESEM对SACTS的结构和形貌进行表征。探讨了缚酸剂用量、丁二酸酐用量、反应时间、反应温度对SACTS羧基含量和酯化率的影响。结果表明合成SACTS较优合成工艺条件为：m（B-CTS）：m（三乙胺）=1:4，丁二酸酐用量为m（B-CTS）：m（SAA）=1:5，反应时间为6.5h，反应温度为65℃。此工艺条件下合成的SACTS的羧基含量为93.01%，酯化率为71.13%。将SACTS与配制的吡罗红染料废水进行絮凝实验，考察了pH、初始浊度、温度对絮凝效果的影响。结果表明：当絮凝条件为在pH=1~4，投加量为1~10mg/L，初始浊度为200~800NTU，温度为20~30℃范围，絮凝后上清液浊度去除率为95%以上，吡罗红染料残余率为10%以下。对上清液Zeta电位和絮体XPS谱图分析表明，SACTS与吡罗红染料废水的絮凝过程是电中和作用与吸附架桥作用共同实现的。

Abstract:

The formation of Schiff base (B-CTS) by chitosan and benzaldehyde protects the amino group of chitosan,and then B-CTS reacted with succinic anhydride to synthesize succinyl chitosan(SACTS).The structure and morphology of SACTS were characterized by FTIR, 1HNMR, XRD and ESEM.The effects of the amount of acid acceptor, the amount of succinic anhydride, the reaction time and the reaction temperature on the carboxyl content and esterification rate of SACTS were discussed.The results showed that the optimum conditions were as follows: m (B-CTS): m (triethylamine) = 1: 4,dosage of succinic anhydride was m (B-CTS): m (SAA) = 1: 5, The reaction time was 6.5 h and the reaction temperature was 65 ℃.Under this process conditions,The carboxyl content and esterification rate of SACTS were 93.01% and 71.13%, respectively.The flocculation experiment was carried out with SACTS and the prepared pheromone dye wastewater,The effects of pH, initial turbidity and temperature on flocculation were investigated.The results showed that when the flocculation conditions were pH = 1 ~ 4, the dosage was 1 ~ 10mg / L, the initial turbidity was 200 ~ 800NTU, the temperature was 20 ~ 30 ℃, the turbidity removal rate of supernatant was More than 95%, pyrotenine dye residual rate of 10% or less.The zeta potential of the supernatant and the XPS spectra of the flocculation showed that the flocculation process of SACTS and Pyrobinum wastewater was achieved by the interaction between the neutralization and the adsorption bridging.