| Popis: |
Metal–organic frameworks (MOFs) are adsorbents suitable for water treatment. However, they are often water soluble and poorly processible, limiting their industrial applications. This study aims to develop a carbonized MOFs with high adsorption performance based on MOFs. Here, we report the production of Mn-MOF [Mn(DMF)2(H2DHTPA)]n (where DMF is N,N-dimethylformamide and H4DHTPA is 2,5-dihydroxyterephthalic acid) via a solvothermal method. This MOF shows good adsorption performance for various ions but dissolves easily in water. However, Mn-MOF-500 which was obtained by carbonising Mn-MOF at 500 °C shows high water stability. Thus, the adsorption properties of Mn-MOF-500 were investigated, revealing adsorption capacities for PO43-, Cd(II), Pb(II), Cu(II), As(III), and As(V) of 126.66, 88.46, 356.21, 146.92, 51.28, and 166.10 mg/g, respectively. Based on the adsorption isotherms and the adsorption kinetics, the adsorption of PO43-, Cd(II), and As(III) occurs via monolayer chemisorption, whereas that of Pb(II), Cu(II), and As(V) occurs via monolayer chemisorption and physisorption in pores. X-ray diffractometry and X-ray photoelectron spectroscopy analysis showed that P, Cd(II), Pb(II), Cu(II), As(III), and As(V) were adsorbed on Mn-MOF-500 as PO43-, Cd(OH)2, PbO and Pb(OH)2, Cu(OH)2, Mn3(AsO3)2, and MnHAsO4, respectively. |
