Optimisation and modeling of Organic Toxin elimination in waste water Based on Mesoporous GNS/NiO Nanocomposite

This study, optimise the elimination of Bromophenol blue (BPB) dye from aqueous solutions using NiO nanoparticles and mesoporous graphene nano sheets/NiO(GNS/NiO) nanocomposite.Co-precipitation and hydrothermal methods were used to prepare both adsorbents. The structural properties have been analysed using X-ray diffraction, FTIR spectroscopy, DLS, TGA, SEMin addition to TEM investigations. The influence of adsorption factors as well as potential of hydrogen (2-12), sorbent amount (0.015-0.035 g/0.03 L) has been optimised using response surface methodology based on central composite design RSM/CCD.Also time (20-120 min), dye concentration (10-100 mg/L), beside temperature (298-339 K) was investigated. The optimum removal efficiency of Bromophenol blue (BPB) dye at 298 K reached to 61.5% and 83.5% at potential of hydrogen = 7 and catalyst dosage = 0.03 g/0.03 L for both adsorbents NiO and GNS/NiO, respectively. The pseudo-2(nd)-order model efficiently discusses sorption kinetics with a better correlation coefficient value R(2)of (0.98 and 0.994) for NiO and GNS/NiO, respectively, indicating chemisorption. Both of Langmuir and Freundlich models could precisely explain adsorption isotherm with R(2)value more than 0.9 indicating monolayer sorption in a homogenous manner. Thermodynamic factors indicate that BPB sorption was endothermic and spontaneous processes by both sorbents and maximum capacity reached to 90 and 95 mg/g for both NiO and GNS/NiO, respectively, at 339 K.

Automated summary

This study optimized the removal of the BPB dye from aqueous solutions using NiO nanoparticles and mesoporous graphene nano sheets/NiO nanocomposite. The maximum removal efficiency reached 61.5% and 83.5% for NiO and GNS/NiO, respectively. The research indicates the high adsorption capacity and stability of the method.