PHYTOCHEMICAL MEDIATED SYNTHESIS OF NICKEL OXIDE NANOPARTICLES USING ANANAS COMOSUS AND ITS APPLICATION IN WATER TREATMENT

Abstract

In the present study, Nickel oxide nanoparticles (NiO NPs) were synthesized using Ananas comosus (pineapple) plant extract via a completely eco-friendly method where no toxic solvents or precursors were used. Various techniques were used to characterize the synthesized NiO NPs. The XRD analysis indicated that the average crystal size of NiO NPs was 20.31 nm. The FTIR analysis confirms the NiO formation with the Ni-O band's appearance at 465 cm-1 . The synthesized NiO NPs were used to investigate the removal of different azo dyes such as Congo red, methylene blue, and crystal violet that may pose a threat to the environment in water. Among all the investigated dyes, NiO NPs have been demonstrated to be effective adsorbents for the removal of hazardous anionic dyes in polluted water, such as Congo Red (CR). Therefore, further studies such as effect of contact time, effect of different concentrations, and effect of adsorbent dosage were studied for the removal of CR dye. It was found that Langmuir's isotherm (R2 = 0.97629) and pseudo-second-order (R2 = 0.99431) provided the best fit for the isotherm and kinetic models, respectively. In addition, the sorbent's maximum adsorption capacity was calculated to be 46.92 mg/g. Hence, NiO NPs synthesized via a greener approach can be used as an efficient sorbent for the sequestration of toxic dyes from wastewater.