Abstract Water pollution due to discharge of dye containing effluents is one of the environmental problems of serious concern today. The main purpose of study is to investigate the efficiency of magnesium oxide nanoparticles (MgO-NPs) on the removal of Reactive blue 19(RB19) from its aqueous solution. The influence of various process parameters such as pH (3 – 11), dosage of MgO-NPs (0.3 – 2.3 g/L), contact time (20 – 150 min), and concentration of RB19 (50 – 200mg/L) was studied using batch adsorption technique. Thermodynamic parameters were also evaluated. The maximum RB19 removal efficiency of 81% was reached at an optimum contact time of 60 min, pH 3, MgO NPs dosage of 1.5 g/L, and initial RB19 concentration. RB19 adsorption on MgO NPs was found to depend on the pseudo-second-order kinetic model which indicates a chemisorption process. The Freundlich adsorption isotherm model best described the removal of RB19 on MgO NPs. The adsorption process was found to be favourable since the intensity of adsorption, n (0.35) lies within 1 to 10. The maximum monolayer adsorption capacity, qm of 7.9 mg/g was obtained. The RB14 adsorption was also found to endothermic in nature. The efficiency was decreased with an increase in temperature implying the process should be performed at a controlled temperature. Results obtained showed that the MgO-NPs could effectively remove RB19from the RB19 containing effluent.
Keyword: Adsorption Isotherm, Kinetics, Nanoparticles, Reactive blue 19, Thermodynamics.