摘要
以钛酸四丁酯交联双醛淀粉,然后与1-(3-氨基丙基)咪唑反应制备了1-(3-氨基丙基)咪唑改性双醛淀粉(TAST)重金属吸附剂。采用元素分析仪、傅立叶变换红外光谱、扫描电子显微镜等表征手段对TAST进行了表征。详细研究了TAST对水溶液中Cu^(2+)离子的吸附行为和吸附机理。结果表明,当吸附温度为35℃、pH为6.5、吸附时间为240 min时,TAST对Cu^(2+)的饱和吸附量达到45 mg·g^(-1)。TAST对Cu^(2+)离子的吸附过程为准二级吸附动力学过程,等温吸附模型同时符合Langmuir和Freundlich方程。这种吸附行为与咪唑啉配位结合Cu^(2+)作用相吻合,且为自发、吸热的熵增过程。电子顺磁共振波谱、X-射线光电子能谱、密度泛函理论计算进一步证实了咪唑啉氮配位的吸附机理。采用絮凝法+TAST结合的工艺,进一步对铜矿废水进行处理,废水中铜离子去除率达到99.45%,满足城镇废水排放标准,表明TAST是一种有潜力和应用价值的吸附剂。
N-(3-Aminopropyl)-imidazole modified dialdehyde starch(TAST)was prepared from tetrabutyl titanate cross-lined dialdehyde starch and N-(3-aminopropyl)-imidazole via a Schiffbase reaction.Its structure was characterized by EA,FTIR,and SEM.It was employed as adsorbent for Cu^(2+)fixation.The adsorption behavior and mechanism of TAST toward Cu^(2+)were carefully investigated.Under the optimal conditions of temperature at 35℃,pH of 6.5,and the equilibrium time of 240 min,the TAST achieved a high adsorption capacity of 45 mg·g^(-1).The adsorption behavior of Cu^(2+)onto TAST followed pseudo-second-order kinetic mode,and adsorption isotherm had an accordance to both Langmuir and Freundlich models.The adsorption process was a spontaneous,endothermic and entropy increase process.These phenomena suggested that the nitrogen in imidazole played an important role for Cu^(2+)fixation.ESR,XPS and DFT calculations also confirmed the interaction mechanism between Cu^(2+)and TAST via the coordination of imidazole functional group.Furthermore,the treatment of copper mine waste water by flocculation and TAST adsorbent exhibited a high removal of 99.45%,meeting the urban wastewater discharge standards.This study showed that TAST was a promising adsorbent with high application value.
作者
容学德
满若君
RONG Xue-de;MAN Ruo-jun(College of Preparatory Education,Guangxi Minzu University,Nanning 530006,China;School of Chemistry and Chemical Engineering,Guangxi Minzu University,Nanning 530006,China;Guangxi Key Laboratory for Polysaccharide Materials and Modification,Nanning 530006,China)
出处
《化学研究与应用》
北大核心
2025年第7期1921-1928,共8页
Chemical Research and Application
基金
广西少数民族预科教育基地重大项目(YJJDA202001)资助
广西科技计划项目(桂科AD20159070)资助。
作者简介
通讯作者:容学德(1977-),男,讲师,主要从事材料化工研究。E-mail:rongxuede1314@163.com。
