Publication Type
Journal Article
Publication Date (Issue Year)
7-15-2024
Journal Name
Ecotoxicology and Environmental Safety
Abstract
Desorption and adsorbent regeneration are imperative factors that are required to be taken into account when designing the adsorption system. From the environmental, economic, and practical points of view, regeneration is necessary for evaluating the efficiency and sustainability of synthesized adsorbents. However, no study has investigated the optimization of arsenic species desorption from spent adsorbents and their regeneration ability for reuse as well as safe disposal. This study aims to investigate the desorption ability of arsenic ions adsorbed on hybrid granular activated carbon and the optimization of the independent factors influencing the efficient recovery of arsenic species from the spent activated carbon using central composite design of the response surface methodology. The activated carbon before the sorption process and after the adsorption-desorption of arsenic ions have been characterized using SEM-EDX, FTIR, and TEM. The study found that all the investigated independent desorption variables greatly influence the retrievability of arsenic ions from the spent activated carbon. Using the desirability function for the optimization of the independent factors as a function of desorption efficiency, the optimum experimental conditions were solution pH of 2.00, eluent concentration of 0.10 M, and temperature of 26.63 ℃, which gave maximum arsenic ions recovery efficiency of 91 %. The validation of the quadratic model using laboratory confirmatory experiments gave an optimum arsenic ions desorption efficiency of 97 %. Therefore, the study reveals that the application of the central composite design of the response surface methodology led to the development of an accurate and valid quadratic model, which was utilized in the enhanced optimization of arsenic ions recovery from the spent reclaimable activated carbon. More so, the desorption isotherm and kinetic data of arsenic were well correlated with the Langmuir and the pseudo-second-order models, while the thermodynamics studies indicated that arsenic ions desorption process was feasible, endothermic, and spontaneous.
Keywords
Adsorbent, Adsorption, Arsenic, Desorption, Eluent, Optimization
Rsif Scholar Name
Jonas Bayuo
Thematic Area
Minerals, Mining and Materials Engineering
Africa Host University (AHU)
Nelson Mandela African Institution of Science and Technology (NM-AIST), Tanzania
Funding Statement
This work was funded by the Partnership for Applied Sciences, Engineering, and Technology-Regional Scholarship and Innovation Fund (PASET-Rsif) and the Carnegie Corporation of New York (CCNY) with grant number P165581. In addition, this work was supported by the Korea Forest Service (Korea Forestry Promotion Institute) through the R&D Program for Forest Science Technology (Project No. 2023483B10–2325-AA01).
Recommended Citation
Bayuo, J., Rwiza, M., Choi, J., Sillanpää, M., & Mtei, K. (2024). Optimization of desorption parameters using response surface methodology for enhanced recovery of arsenic from spent reclaimable activated carbon: Eco-friendly and sorbent sustainability approach. Ecotoxicology and Environmental Safety, 280 https://doi.org/10.1016/j.ecoenv.2024.116550