Iron based metal organic framework for efficient removal of methylene blue dye from industrial waste

The present investigation assesses the applicability of Fe-BDC metal organic framework for the removal of the toxic dye methylene blue from industrial waste. The adsorption characteristics and dye removal efficiency of Fe-BDC MOF has been determined by investigating factors such as effect of contact time, concentration of the dye, amount of adsorbents, and temperature. Upto 94.74% dye removal was attained by increasing the dose of adsorbent and temperature. Maximum 94.74% dye removal was achieved after 24 h, on adding 25 mg of Fe-BDC MOF to dye solution of MB having concentration 5 mg/L. Langmuir, Freundlich and Tempkin, isotherm models have been used to evaluate the ongoing adsorption. Freundlich adsorption isotherm was found to be best fitted for the adsorption process. On the basis of pseudo-first-order, pseudo-second-order and intra particle diffusion kinetic equations, different kinetic parameters have been obtained. Pseudo second order kinetic model with rate constant (k2) 4.9 × 10−2 g/mg·min, is found to be best fitted for adsorption of methylene blue on Fe-BDC MOF indicating that removal of dye takes place dominantly through chemisorption process.