title: Preparation of quaternary ammonium-Chlorella vulgaris and its adsorption of Ag(CN)2-.
abstract: A novel anion exchange resin, quaternary ammonium-Chlorella vulgaris (QACV), was prepared by introducing quaternary ammonium groups onto dried Chlorella vulgaris as base material. Degrees of epoxy, amine and quaternary ammonium groups of QACV were measured. Water retention, optical microscopy, and Fourier transform infrared spectrometry were used to characterize QAVC. The adsorption behavior of QACV towards Ag(CN)2- in different conditions was studied carefully. The results showed that QAVC was efficient to adsorb Ag(CN)2- at pH 9-11, and adsorption equilibrium was almost reached in 30 min. Both kinetics and isotherm parameters in the adsorption process were obtained. The data indicated that the pseudo-second-order model provided a good correlation for adsorption of Ag(CN)2- on QACV and the calculated rate constant of the adsorption was 3.51 g/(mmol min). The equilibrium data fitted well in the Langmuir isotherm and the estimated maximum adsorption capacity qm was 1.96 mmol/g. The dimensionless separation factor RL was between 0 and 1, suggesting that the adsorption process of Ag(CN)2- using QACV was favorable. The QACV could be used successively three times without significantly affecting its adsorption efficiency. Chlorella vulgaris was a potential base material to be modified with quaternary ammonium groups to prepare an adsorbent for adsorption of Ag(CN)2-.
authors.affiliation: Department of Pharmaceutical & Biological Engineering, College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China E-mail: zhangyongkui@scu.edu.cn.
authors.forename: Ting
authors.initials: T
authors.lastname: Li
authors.affiliation: Department of Pharmaceutical & Biological Engineering, College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China E-mail: zhangyongkui@scu.edu.cn.
authors.forename: Chencen
authors.initials: C
authors.lastname: Guo
authors.affiliation: Department of Pharmaceutical & Biological Engineering, College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China E-mail: zhangyongkui@scu.edu.cn.
authors.forename: Tonghui
authors.initials: T
authors.lastname: Xie
authors.affiliation: Department of Pharmaceutical & Biological Engineering, College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China E-mail: zhangyongkui@scu.edu.cn.
authors.forename: Chengxianyi
authors.initials: C
authors.lastname: Zhou
authors.affiliation: Department of Pharmaceutical & Biological Engineering, College of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China E-mail: zhangyongkui@scu.edu.cn.
authors.forename: Yongkui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D000327:Adsorption; D064751:Ammonium Compounds / Q000737:chemistry*; D000837:Anion Exchange Resins / Q000138:chemical synthesis*; D048408:Chlorella vulgaris / Q000737:chemistry*; D003486:Cyanides / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D018030:Silver Compounds / Q000737:chemistry*
chemical_list: D064751:Ammonium Compounds; D000837:Anion Exchange Resins; D003486:Cyanides; D018030:Silver Compounds