Adsorption of hydrogen arsenate and dihydrogen arsenate ions from neutral water by UiO-66-NH2. (1st October 2019)

• Record Type: Journal Article
• Authors: Chang, Zu-Wei; Lee, Yu-Jen; Lee, Duu-Jong
• Is Part Of: Journal of environmental management. Volume 247(2019)
• Page Start: 263
• Page End: 268
• Publication Date: 2019-10-01
• Subjects: UiO-66-NH2 -- Arsenate -- Adsorption -- Acid treatment -- Capacity; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2019.06.068
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: The metal-organic framework (MOF) UiO-66-NH2 was synthesized with different substrate to solvent ratios and its morphology, surface area, pore distributions, and NMR, XRD, and TGA-FTIR patterns were obtained. Adsorption tests at pH 7 and 25 °C showed that the produced UiO-66-NH2 has a hydrogen arsenate adsorption capacity of 76.9 mg/g. With the affinity onto Zr clusters, this MOF also can adsorb phosphate ions from water. Treatment with 1–4 M hydrochloric acid (HCl) protonated the amine groups in the MOF. Treatment with 1 M HCl at 25 °C for 6 h maximized the adsorption capacity of UiO-66-NH2 to 161.3 mg/g, such that the protonated amine groups accounted for 53.7% of the adsorption of arsenate from the water. The use of excessively strong acid at elevated temperature reduced the adsorption capacity. Highlights: Metal-organic framework (MOF) UiO-66-NH2 was synthesized and characterized. Adsorption capacity at pH 7 and 25 °C is 76.9 mg/g of hydrogen arsenate. 1M HCl treatment at 25 °C for 6 h increases adsorption capacity to 161.3 mg/g. Protonated amine groups accounts for enhanced adsorption of arsenate ions.