The Adsorption Capacity of Activated Carbon Madefrom Walnut Shells: Composition, Properties and Environmental Applications

Due to its admirable adsorption capacity, activated carbon is used widely as an adsorbent. Thus, it proves to be an effective adsorbent for environmental remediation, water purification, and air cleaning. The present work takes a perspective on the synthesis, characterization, and adsorption behavior of activated carbon from walnut shell, an environmental waste material of huge renewable source. High-surface-area activated carbon with high adsorption capacity was prepared by chemical activation based on the utilization of phosphoric acid. The synthesized AC is characterized by using sophisticated techniques: SEM, FTIR, BET, and XRD. Batch adsorption tests using methylene blue (MB) were carried out to measure adsorption efficiency, with recorded maximum adsorption capacity reaching 450 mg/g. These results highlight the walnut shell activated carbon as an efficient, economical, and green adsorbent. This shows the feasibility of this material on the industrial scale for applications to purify water and air: a safe method for treating agricultural waste besides fighting against environmental pollution. Results reveal that even moderate conditions lead to a very porous architecture with BET surface area higher than 1200 m²/g. FTIR and XRD illustrate functional groups and the presence of amorphous carbon structures, corresponding to SEM images of a well-defined porous network. These results underline that WSAC can serve as an effective, sustainable, and economic adsorbent that can find applications in extra-large environmental applications, elaborating a circular economy concept converting agricultural waste into resources for pollution elimination.