High-performance petal-like nickel organic framework for efficient dye sequestration

Abstract

Discharge of industrial effluents, with organic dye as a major component, is an important contributor to water pollution which requires efficient techniques for removal. Here, a mesoporous nickel-based metal organic framework (Ni-MOF) with flowerlike morphology was synthesized using 2-methyl imidazole as ligand via solvothermal method. The product formed was applied for Coomassie brilliant blue (CBB) dye removal through physical adsorption. The influence of four parameters (adsorbate dosage, adsorbent dosage, pH and contact time) on the dye adsorption capacity of the Ni-MOF was then examined with the result showing that the rate and efficiency of adsorption is dependent on these parameters. At a minimum adsorbent dosage of 10 mg, complete dye removal was achieved for 100 mg/mL adsorbate at pH of 4.0 within 60 min contact time, with an adsorption capacity of ∼19.9 ± 0.1 mg/g. Adsorption kinetics and adsorption isotherm studies also revealed that CBB adsorption by the Ni-MOF is a spontaneous physisorption process with pseudo-second order kinetics and Langmuir isotherm model producing the best fit, respectively.