Author(s)

Onyeka Samuel Ojinna¹, Yueli Wen^1*, Bin Wang², Chengda Li², Wei Huang^2,3, Ikeh Justin Tobechukwu⁴

¹College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China.
²State Key Laboratory of Clean and Efficient Coal Utilization, Taiyuan University of Technology, Taiyuan, China.
³Coal Conversion Technology & Engineering Co., Ltd., Taiyuan University of Technology, Taiyuan, China.
⁴Geological Resources and Geological Engineering, Taiyuan University of Technology, Taiyuan, China.

The world wide application of dyes in papermaking, fabric, lithography, leather and other industrial production, has attracted more attention, due to water pollution caused by these organic dyes. Metal-organic frameworks (MOFs) which are a physical adsorption method of wastewater treatment are a kind of special three-dimensional crystal-like constituents built by multipurpose ligands and metallic ion classes, showing an advantage in removal of pollutants from solutions because of its unique properties are convenient for operation, high removal efficiency, and low cost. In this study, we investigated Fe-Mg based metal organic framework, Fe-Mg MOFs which was directly synthesized by the hydrothermal method. The obtained materials were analyzed with XRD, FT-IR, TG-DTG, SEM etc. and used for the treatment of printing and dyeing wastewater. The results showed that it has good adsorption performance for cation dye rhodamine B (RhB) and anion dye methyl orange (MO) in a wide pH range. The Fe-Mg MOF even after the 4^th run, the Fe-Mg MOF catalyst still maintained nearly the initial catalytic activities. The kinetic studies revealed the adsorption process of the both contaminants obeys a pseudo-second order model. In addition, the equilibrium adsorption data of RhB and MO are in good agreement with Langmuir models. The maximum adsorption capacities are 694.44 and 236.97 mg/g at 308 K respectively. This work synthesizes a promising dual-functional adsorbent that can remove cationic and anionic dyes, which provide potential applications for actual wastewater treatment.

Metal-Organic Frameworks (MOFs), Adsorption, Cationic and Anionic Dyes, Wastewater Treatment

Ojinna, O. , Wen, Y. , Wang, B. , Li, C. , Huang, W. and Tobechukwu, I. (2022) Preparation of Fe-Mg MOFs and Its Application in Removal of RhB and MO. Journal of Geoscience and Environment Protection, 10, 167-180. doi: 10.4236/gep.2022.104011.