This review study is dealing with the recent advances and developments in the metal-organic framework (MOF) materials especially in the aspect of environmental remediation of heavy metals. Its application in some area of technological and mechanical advancement was also considered. The process of its synthesis and characterization was also put into consideration. Metal-organic frameworks can be said to be an exciting new class of nanoporous crystalline materials containing a metal as its central ion surrounded by organic ligands. An overwhelming characteristic of MOFs lies in its surface area which is amazingly large, exceeding those of known best activated carbons and zeolites. There is an increasingly high demand in the application of MOFs for a multitude of environmental uses or application to be used for capturing and separating various unwanted or even environmentally harmful chemicals, elements or materials. The advantage of MOFs over other known adsorbent materials, such as zeolites and carbon black, is that it possesses a far greater surface area along with amazingly great pore properties. In this review the synthesis and characterization of MOFs, the fate of heavy metals, the application of MOFs in heavy metals remediation and other means of heavy metals remediation are well discussed.

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Environmental pollution by industrial effluent has become an important issue partly because of the detection of heavy metals in them which need to be mitigated. Adsorbents were produced from Bentonite clay using 2 M H2SO4 and HCl as modifying agents in ratio 1:2 by wet impregnation method. Physicochemical properties of the pharmaceutical effluents such as pH, temperature, turbidity, conductivity, Chemical Oxygen Demand (COD), Biological Oxygen Demand (BOD) and heavy metals were determined. High concentration of Fe(III) and Zn(II)were observed in the effluents when compared with standards. Optimal value of pH for Fe(III) and Zn(II) were 8 and 7 respectively and dose of 0.1 g was found to be optimal value for all the adsorption system. The adsorption was best fit to Langmuir isotherm and the pseudo second order kinetic model. The results obtained in this study showed that the produced adsorbents could be used to supplement the commercial adsorbents in the specific application. Furthermore, acid modification was helped to increase the sorption capacity of the clay to the heavy metals studied with H2SO4 being the better modification agent.