Investigation of adsorption of p-cresol on coconut shell-derived activated carbon

Abstract Mitigation of odorous volatile organic compounds, such as p -cresol from wastewater needs simple and practical technologies such as adsorption. In this research, an NaOH-activated carbon was prepared from coconut shell (CSAC-SH). Characterization of CSAC-SH suggested that the adsorbent possessed a well-developed microporous/mesoporous structure. To evaluate the performance of CSAC-SH, a series of batch experiments were conducted to investigate the effects of contact time (0–24 h), initial concentration (50–1000 mg L −1 ) and adsorbent dosage (1–20 mg L −1 ) on adsorption of p -cresol. The equilibrium data were found to conform to Redlich–Peterson, Fritz–Schluender, and Langmuir isotherms. The maximum monolayer adsorption capacity of 256.9 mg g −1 (298 K) suggested that the prepared adsorbent has a high affinity toward p -cresol. A second-order kinetic model best described the experimental data and adsorption was governed by intraparticle diffusion. The thermodynamic analysis suggested that the adsorption was feasible, spontaneous, and exothermic (298–328 K). Furthermore, a desorption study suggested that chemisorption was dominant in the adsorption process. Results indicate that sodium hydroxide-activated carbon is effective in mitigating p -cresol from wastewater.