Study of Methylene Blue dye adsorption onto biochar derived from Austrocylindropuntia subulata plant

Abstract The reuse of treated wastewater in drinking water supply and irrigation emerges as a potent solution to address water scarcity. Recent years have witnessed a growing interest in wastewater treatment using ecological, non-toxic, and biodegradable materials. In this study, Austrocylindropuntia subulata was employed for the first time to adsorb a synthetic dye, methylene blue. The feedstock underwent pyrolysis followed by chemical activation using orthophosphoric acid, resulting in the formation of biochar. Characterization through SEM, XRD, and FTIR analyses reveals that the biochar surface possesses functional groups such as alcohol and amide. Microscopic images highlight a diverse array of particle shapes and sizes, along with varying proportions of calcium and carbon in the biochar. Adsorption tests demonstrate that the optimal mass of biochar is 0.5g, ensuring a remarkable 99.8% adsorption of methylene blue dye within a 30 minutes contact time. The findings of this study underscore the compelling adsorbent capabilities of biochar derived from the Austrocylindropuntia subulata plant, suggesting its potential as a valuable resource in wastewater treatment.