Anionic Methyl Orange Removal from Aqueous Solutions by Activated Carbon Reinforced Conducting Polyaniline as Adsorbent: Synthesis, Characterization, Adsorption Behavior, Regeneration and Kinetics Study

This work investigated the elimination of Methyl Orange (MO) using a new adsorbent prepared from Activated Carbon (AC) with polyaniline reinforced by a simple oxidation chemical method. The prepared materials were characterized using XRD, TGA, FTIR and nitrogen adsorption isotherms. Furthermore, PANI@CA highest specific surface area values (near 332 m(2) g(-1)) and total mesoporous volume (near 0.038 cm(3) g(-1)) displayed the better MO removal capacity (192.52 mg g(-1) at 298 K and pH 6.0), which is outstandingly higher than that of PANI (46.82 mg g(-1)). Besides, the process's adsorption, kinetics, and isothermal analysis were examined using various variables such as pH, MO concentration and contact time. To pretend the adsorption kinetics, various kinetics models, the pseudo first- and pseudo second- orders, were exercised to the experimental results. The kinetic analysis revealed that the pseudo second order rate law performed better than the pseudo first order rate law in promoting the formation of the chemisorption phase. In the case of isothermal studies, an analysis of measured correlation coefficient (R-2) values showed that the Langmuir model was a better match to experimental results than the Freundlich model. By regeneration experiments after five cycles, acceptable results were observed.

Automated summary

The study found that the PANI@CA adsorbent had higher specific surface area and mesoporous volume, demonstrating superior removal capacity for MO compared to PANI alone. Kinetic and isothermal analysis indicated that the pseudo second order kinetics and Langmuir model provided better fit to the experimental results.