A sustainable cationic chitosan/E-coli fiber biosorbent for Pt(IV) removal and recovery in batch and column systems

作者：Mao Juan^*; Kim Sok; Wu Xiao Hui; Kwak In Soeb; Zhou Tao; Yun Yeoung Sang

来源：Separation and Purification Technology, 2015, 143: 32-39.

DOI：10.1016/j.seppur.2015.01.023

• Chitosan fiber
• E. coli
• Pt(IV)
• Batch system
• Column system

In this study, the cationic bacterial biosorbent, poly(allylamine hydrochloride) (PAA/HCl)-modified Escherichia colt was successfully immobilized as a chitosan fiber, which was proved to be a sustainable biosorbent for platinum removal and recovery from aqueous solutions in batch and column systems. Compared to the commercial ion exchange resins, PAA/HCl-modified E. coli chitosan fiber showed a quite good performance for Pt(IV) removal. Two-parameter (Langmuir and Freundlich) and three-parameter (Sips and Redlich-Peterson) models were employed to describe the batch isotherm experimental data. Among these four models, the Redlich-Peterson model fit best, with higher coefficient of determination, chi-square and average percentage error values. Thermodynamic parameters (Delta G(0) < 0 and Delta H-0 > 0) showed the spontaneity and endothermic nature of biosorption process. The kinetics of Pt(IV) biosorption with different initial concentrations were better fit by the pseudo-second-order model, with higher coefficient of determinations and more closely predicted q(e) values. An acidified 0.005 M thiourea was used to regenerate platinum from exhausted biosorbent maintaining desorption efficiencies over 90.2% until five cycles. In the column studies, the breakthrough curve showed a typical S-shaped curve, with breakthrough and exhaustion times appearing at 36.0 h and 52.5 h, respectively, which was opened up a possibility of column regeneration.

• 出版日期2015-3-25
• 单位华中科技大学