Studies of adsorption kinetics and regeneration of aniline, phenol, 4-chlorophenol and 4-nitrophenol by activated carbon

Abstract

The present paper reports kinetic studies of the adsorption of aniline (AN), phenol (P), 4-chlorophenol (CP) and 4-nitrophenol (NP) from aqueous solution onto granular activated carbon (GAC). In FTIR spectral analysis, the transmittance of the peaks gets increased after the loading of AN, P, CP and NP signifying the participation of these functional groups in the adsorption and it seems that the adsorption of AN, P, CP and NP is chemisorptive in nature. The rates of adsorption were found to obey a pseudo-second order model and that the dynamics of AN, P, CP and NP adsorption are controlled by a combination of surface and pore diffusion. The diffusion coefficient were of the order of 10-10 m2 s-1. Thermal desorption at 623 K was found to be more effective than solvent desorption. GAC performed well for at least five adsorption-desorption cycle, with continuous decrease in adsorption efficiency after each thermal desorption. Owing to its relative high heating value, the spent GAC can be used as co-fuel for the production of heat in a boiler or a furnace

Phenol adsorption on high microporous activated carbons prepared from oily sludge: equilibrium, kinetic and thermodynamic studies

“…The ACs with basic surface characteristics, such as the adsorbents of this study, are considered as the most appropriate and effective adsorbents for the removal of phenol due to the weak acid nature of this molecule. The adsorption of organic compounds onto the ACs mainly contribute to three types of surface–phenol interactions namely, (i) π-π dispersion interaction, (ii) the electron-donor–acceptor complex formation and (iii) the hydrogen-bonding formation 34 that may occur simultaneously. Surface oxygen complexes sites are of Bronsted type.…”

Adsorption of 4-Nitrophenol (PNP) Using Pilli Nut Shell Active Carbon

“…However, an inconsistency in the agreement of the experimental q e and calculated q e for the adsorption of PNP with granular active carbon has been reported [24]. Experimental q e value of 27.41 mg/g was reported and values of 95.70 mg/g and 99.74 mg/g were reported for pseudo-first and pseudo-second kinetic models respectively.…”

“…Another researcher obtained equilibrium after 5 h [24]. Thus, these differences in the time for adsorption process to reach equilibrium could be as a result of the functional groups present on the adsorbent as well as its surface morphology, such as the location and ease of access of the pores responsible for the adsorption.…”

Batch and Continuous Adsorptive Desulfurization of Model Diesel Fuels Using Graphene Nanoplatelets

“…The adsorption rate slows down after the S-compound saturates the meso-and micropores, which may be because the microspores experience a larger resistance in the later stage when the S molecules move further. 46 For interpreting the experimental data, the first-order equation, the pseudo-second-order equation, and an intraparticle diffusion equation were studied. The pseudo-first-order kinetic is given by 47,48…”