Synthesis of magnesium oxide nanoparticles and its application for photocatalytic removal of furfural from aqueous media: Optimization using response surface methodology

Abstract

Furfural is a toxic compound with an LD50 of 65 mg/kg that is produced in many industries, such as paper industries, petrochemical industries, and oil refineries. This compound exists in various concentrations in these industries and is released into the environment. Therefore, removing this contaminant from the wastewater of production units is among the environmental priorities of every company. This study investigated the optimization of photocatalytic removal of furfural using synthesized magnesium oxide nanoparticles (MgONPs) by the response surface method (RSM). In this study, MgONPs were prepared by the direct precipitation method, and the characteristics of the nanoparticles (NPs) were examined using XRD and SEM analyses. The effect of various operating parameters, including pH (3, 7, and 11), contact time (15, 90, and 165 min), initial concentration of furfural (25, 150, and 275 mg/L), dose of NPs (125, 687.5, and 1250 mg/L), and UV radiation intensity (8, 15, and 30 µW/cm2) on furfural removal was explored. Furfural concentration was measured using a spectrophotometer at a wavelength of 277 nm. The number of samples was determined by the CCD method. Data were analyzed using MINITAB 16 software. The optimal removal conditions based on variance analysis and appropriate model were obtained at a pH of 6, NP dose of 1 g/L, initial concentration of 250 mg/L, reaction time of 160 min, and UV radiation intensity of 30 µW/m2. Under these conditions, the removal efficiencies for both furfural and COD were 99.97%. The results of the analysis of the synthesized MgONPs also showed that the direct precipitation method is a fast and low-cost method for the synthesis of MgONPs. Results showed that the photocatalytic process in the presence of synthesized MgONPs is highly efficient in removing furfural from aqueous media.

Keywords

• Synthesized MgONPs
• Photocatalytic Process
• Furfural
• Response surface methodology (RSM)