title: Uptake of gold (III) from waste gold solution onto biomass-based adsorbents organophosphonic acid functionalized spent buckwheat hulls.
abstract: Novel biomass-based adsorbents organophosphonic acid functionalized spent buckwheat hulls (OPA-BH) with 60 mesh were successfully employed to adsorb Au(III) ions from simulated wastewater. The adsorption kinetics and isotherms both in unary ion system and in ternary ions system were investigated, and the applicability of the Langmuir, Freundlich and extended Langmuir isotherm models has been tested for the equilibrium. The process optimization was also conducted by using response surface methodology (RSM), and the maximum adsorption capacities reached 2.84 ± 0.01 mmol/g under the optimum process conditions. Furthermore, the regeneration capacities of OPA-BH were investigated by using the eluent solutions of 0.0-5.0% thiourea in 0.1 mmol/L HCl, and the results showed that the adsorption capabilities for OPA-BH were ranged between 0.77 mmol/g and 0.85 mmol/g after three cycles of adsorption-desorption processes. The research results showed that OPA-BH was favorable and useful for gold adsorption, and the high adsorption capacity and good reproducibility make it a good promising material for the precious metal uptake.
authors.affiliation: School of Chemistry and Materials Science, Ludong University, Yantai 264025, PR China. yinping426@163.com
authors.forename: Ping
authors.initials: P
authors.lastname: Yin
authors.forename: Mingyu
authors.initials: M
authors.lastname: Xu
authors.forename: Rongjun
authors.initials: R
authors.lastname: Qu
authors.forename: Hou
authors.initials: H
authors.lastname: Chen
authors.forename: Xiguang
authors.initials: X
authors.lastname: Liu
authors.forename: Jiang
authors.initials: J
authors.lastname: Zhang
authors.forename: Qiang
authors.initials: Q
authors.lastname: Xu
mesh_terms: D000327:Adsorption; D001673:Biodegradation, Environmental; D018533:Biomass; D012968:Etidronic Acid / Q000737:chemistry*; D019612:Fagopyrum / Q000737:chemistry*; D006046:Gold / Q000737:chemistry / Q000302:isolation & purification*; D007220:Industrial Waste / Q000517:prevention & control; D012639:Seeds / Q000737:chemistry*; D062065:Wastewater / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000302:isolation & purification*; D018508:Water Purification
chemical_list: D012968:Etidronic Acid; D006046:Gold; D007220:Industrial Waste; D062065:Wastewater; D014874:Water Pollutants, Chemical