BACKGROUND AND OBJECTIVES: With urban populations struggling with wastewater and water sources contaminated by metalloids, the demand for sustainable and effective methods for removing heavy metals is growing ever more urgent. Arsenic contamination in wastewater and water supplies is a critical environmental concern worldwide, posing severe health risks and demanding effective mitigation strategies. With numerous regions contending with increased arsenic levels, it is crucial to explore various removal strategies to maintain water quality and safeguard public health. Employing biomass obtained from waste materials offers an affordable and uncomplicated strategy for the removal of environmental pollutants. This study's objective was to evaluate the ability of biomass derived from Prosopis juliflora fruit to uptake arsenic from wastewater. METHODS: Following the drying process, the harvested biosorbent was processed into a fine powder through grinding. All tests utilized the biomass that had been refined to powder sizes of less than 45 micrometers. An assessment of arsenic adsorption was conducted using response surface methodology, focusing on the effects of several operational parameters, including the biosorbent to arsenic ratio, solution potential of hydrogen, and the contact time between the biomass and the analyte. Additionally, the optimal conditions for maximizing arsenic removal by the biomass of Prosopis juliflora were determined through the Box-Behnken approach. Kinetic studies were conducted to statistically analyze the trivalent arsenic adsorption process. FINDINGS: The effectiveness of the proposed model in identifying the optimal conditions for the trivalent arsenic uptake process was validated through testing. The analysis of experimental data revealed the coefficient of determination, adjusted coefficient, and predicted coefficient values to be 0.9936, 0.9820, and 0.9053, respectively. According to the results, the highest adsorption of arsenic ions by the biomass was achieved at 91.11 percentage, with Prosopis juliflora fruit biomass to-arsenic ratio of 8:1, potential of hydrogen of 7.5, and a contact time of 90 minutes. CONCLUSION: The findings of this study indicate that the biomass of Prosopis juliflora fruit serves as an efficient sorbent for the removal of trivalent arsenic from water under optimal conditions. The adsorption data aligned with pseudo-second-order kinetics, with a maximum capacity of 114.94 milligrams per gram, suggesting that the adsorption of trivalent arsenic onto the Prosopis juliflora occurs in monolayers.
