Synthesis and Characterization of Activated Carbon from Agrowastes for the Removal of Acetic Acid from an Aqueous Solution

In this study, activated carbons prepared from agrowastes by chemical activation were used to remove acetic acid from an aqueous solution through a batch process. The prepared adsorbents were characterized by SEM, XRD, FT-IR, and point of zero charge (pHpzc). The effects of adsorbent dosage, initial concentration, and contact time were considered. Equilibrium data was tested using Langmuir, Freundlich, Temkin, and Frenkel-Halsey-Hill models. The degree of adsorption of acetic acid increased for both adsorbents as contact time, and adsorbent dosage and initial concentration were increased. The adsorption data were described well by the (Freundlich=Frenkel-Halsey-Hill) models with the highest regression coefficient of R-2=0.9961 and R-2=0.9951 for Rice Husk Activated Carbon (RH-AC) and Potato Peels Activated Carbon (PP-AC), respectively. This suggests a multilayer through the existence of a heterogeneous pore distribution in the adsorbent surface. Kinetic data agreed well with pseudosecond-order (R-2=0.999 and R-2=0.994) RH-AC and PP-AC, correspondingly. This indicates that the adsorption process was chemisorption in nature. The regeneration studies showed that the adsorbents prepared could be renewed and reused before losing their adsorbing affinity for acetic acid.

Automated summary

In this study, activated carbons prepared from agrowastes were used for the removal of acetic acid from aqueous solution. The adsorption process was studied under different conditions, and the results showed that the adsorption capacity increased with increasing contact time, adsorbent dosage, and initial concentration. The adsorption data fitted well with the Freundlich-Frenkel-Halsey-Hill models, indicating a multilayer adsorption process. The kinetic data followed a pseudosecond-order model, suggesting chemisorption. The prepared adsorbents also showed good regeneration and reusability.