树脂吸附法分离去除阿斯巴甜缩合母液中L-苯丙氨酸的特性与机制  

THE REMOVAL PROPERTIES AND MECHANISMS OF L-PHENYLALANINE IN ASPARTAME CONDENSATION SOLUTION BY RESINS ADSORPTION METHOD

作　　者：仇欢[1] 姜伟立[2] 刘福强[1] 公彦猛 姜琦[3] 刘树洋[2] 赵伟 QIU Huan1, JIANG Weili2 ,LIU Fuqiang1, GONG Yanmeng1,2, JIANG Qi3 ,LIU Shuyang2, ZHAO Wei1(1. State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment Nanjing University, Nanjing 210023, China;2. Jiangsu Provincial Academy of Environmental Science, Jiangsu Province Key Laboratory of Environmental Engineering, Nanjing 210036, China;3. Sino-Japanese Friendship Environmental Protection Research Center, Beijing 100029, Chin)

机构地区：[1]污染控制与资源化研究国家重点实验室、南京大学环境学院,南京210046 [2]江苏省环境科学研究院、江苏省环境工程重点实验室,南京210036 [3]中日友好环境保护中心,北京100029

出　　处：《离子交换与吸附》2018年第1期49-62,共14页Ion Exchange and Adsorption

基　　金：江苏省重点研发计划(社会发展)(BE2015724);苏南运河水环境综合整治方案(133365).

摘　　要：研究了两种吸附树脂XAD-300和LS-106对阿斯巴甜缩合母液中L-苯丙氨酸(L-Phe)的分离去除规律,吸附等温线均可采用Langmuir和Freundlich方程拟合,吸附热力学参数表明,吸附过程均是自发的放热过程。XAD-300对L-Phe的焓变值和吸附自由能变值更大,表明该树脂对目标有机污染物具有更强的吸附亲和力。两种树脂对L-Phe的吸附动力学曲线均符合拟二级动力学方程,且XAD-300的初始吸附速率更大,这与XAD-300更强的吸附亲和力有关。动态吸附穿透曲线显示,XAD-300和LS-106的动态穿透点分别为44BV和6BV,且前者的穿透吸附量高达1.70mmol/g,约为后者的3倍。采用0.1mmol/L的稀Na OH溶液即可实现XAD-300的彻底再生,L-Phe的脱附率高达99.6%。阿斯巴甜缩合母液中共存的L-天冬氨酸对L-Phe的去除几乎无影响,而共存氯盐对L-Phe的去除略有抑制。XAD-300对L-Phe的强吸附亲和力主要源于其丰富的微孔结构,在吸附中微孔填充机制发挥了主导作用。The removal and separation properties of L-phenylalanine （L-Phe） in aspartame condensation solution from the adsorption resins XAD-300 and LS-106 were compared. Langmuir and Freundlich models both described the isotherm data well. The adsorption thermodynamics parameters indicated that the adsorption processes were both spontaneous and exothermic. The greater value of △H^φ and AG^φ of L-Phe onto XAD-300 indicated stronger adsorption affinity between them. The adsorption kinetics curves of L-Phe were fitted well by Pseudo-second-order kinetics and the initial adsorption rate of XAD-300 was higher than that of LS-106, which was related to the stronger adsorption affinity of L-Phe onto XAD-300. Dynamic adsorption results revealed that the breakthrough points of L-Phe onto XAD-300 and LS-106 were 44BV and 6BV, respectively, and the breakthrough adsorption amount of XAD-300 was 1.70mmol/g, about three times greater than that of LS-106. Finally, the loaded L-Phe onto XAD-300 was thoroughtly recycled by 0. lmmol/L NaOH and 99.6% L-Phe could be recovered. The amount of aspartic acid had no effect on the adsorption of XAD-300, but the coexistence of sodium chloride slightly inhibited the adsorption of L-Phe. The stronger adsorption affinity of XAD-300 was mainly related to its abundant microporous structure, and the microporous filling may be the dominant mechanism.

关 键 词：吸附树脂 阿斯巴甜 L-苯丙氨酸 分离去除 微孔填充 

分 类 号：O647.3[理学—物理化学]