Comparative Study of MOF's in Phosphate Adsorption

Eniya Karunamurthy, Wright State University


High concentrations of phosphate are known to adversely affect the environment. Excess phosphate can lead to eutrophication that eventually fosters uncontrollable growth of aquatic plants and algae. This can result in depletion of oxygen content which adversely impacts underwater organism’s survival rates. Metal organic frameworks (MOFs) consist of organic linkers in conjunction with metal ions or clusters arranged within a crystalline structure. They are highly porous and have larger surface area due to their ability to possess extensive void spaces while remaining bulky in nature. MOFs can absorb phosphate from aqueous solutions. We have investigated the use of commercially available MOFs to extract phosphate. In this project, activated carbon was utilized as a control sample to compare the adsorption capacity of Metal-Organic Frameworks (MOFs), specifically evaluating Basolite C300, Basolite Z1200, Basolite A100, Basolite F300 and Basolite Z377. Three different pH solutions such as 5, 7, and 9 were used to study the influence of pH in adsorption. The scope of research encompasses both kinetics and Freundlich isotherm assessments. Scanning Electron Microscopy (SEM), Elemental Dispersive X-Ray Analysis (EDAX) and X-Ray Diffraction (XRD) techniques employed to study the MOFs in both pre- and post-adsorption analyses. It was found that some of the MOFs have better adsorption capacity when compared to other adsorbents.