Enhanced adsorptive removal of anionic and cationic dyes from wastewater using MOF PCN-222(M)

The toxicity of the dyes and inappropriate discharge of such wastes play major roles in water pollution and spread of diseases [1]. In this work, harmful dyes (anionic dye(MO) and cationic dye(MB)) have been removed from wastewater. The high dye adsorption capacity overPCN-222 (Cu, Fe, Mn)has been estimated and analyzed using Langmuir and Freundlich equations. The adsorption kinetics, thermodynamic parameters, stability and reusability of the adsorbent have also been reported [2]. The results show that PCN-222(M) has maximum loading of MB and MO. The adsorption capacity of metalloporphyrin framework (PCN-222(M) (M= Cu, Fe, Mn)) ranks at top in comparison with metal-free porphyrin framework (PCN-222). Adsorption capacity has been observed up to eight recycles for dye removal with no significant change in crystal structure.The electrostatic interaction between porphyrinic metal center and MO increases dye adsorption capacity.Values of r2 of a linear plot of the Langmuir model were better than those of the Freundlich model for all three adsorbents (Fig. 1).