Metal-Organic Framework Based on Isonicotinate N-Oxide for Fast and Highly Efficient Aqueous Phase Cr(VI) Adsorption

Synthesis of new porous materials has been developed for efficient capture of pollutants in environmental sciences. Here, the application of a new metal-organic framework (TMU-30) has been reported based on isonicotinate N-oxide as an adsorptive site for fast and highly efficient aqueous phase adsorption of Cr(VI). The adsorption process showed no remarkable effect over a pH range of 2-9. The maximum capacity of the adsorption was reached in just less than 10 min and followed the pseudo-second-order kinetics. The maximum capacity of 2.86 mol mol(-1) (145 mg/g) was obtained according to Langmuir model at 298 K. The spontaneous adsorption and an endothermic process were controlled by positive entropy changes. XPS analysis revealed electrostatic interactions between N-oxide groups of TMU-30 and Cr(VI) species, which were responsible for the adsorption process.