Efficient removal of cobalt(II) ion from aqueous solution using amide-functionalized metal-organic framework

In this study, an amide-functionalized metal-organic framework, namely TMU-24 was selected to adsorb Co(II) from wastewater with an adsorption capacity of 500 mg. g^-1 in less than 20 minutes in neutral pH (pH=7). The effect of diverse parameters such as adsorbent dosage, competitive ions, and contact time on the adsorption process was investigated to find the optimal amounts of them. Also, the modeling calculations demonstrated that this compound obeys Pseudo-Second-order and Langmuir models with correlation coefficients of R² = 0.9996 and R² = 0.9761, respectively. So, the adsorption mechanism could be monolayer chemical interaction according to these models. Moreover, PXRD patterns of the framework before the adsorption procedure and after that revealed that the MOF could keep its structure, suggesting the stability of the framework. So, we can claim that our proposal adsorbent is a promising candidate for cobalt(II) removal from pollutant water.