Dataset on adsorption of phenol onto activated carbons: Equilibrium, kinetics and mechanism of adsorption (2025)

Adsorption and desorption of phenol on activated carbon and a comparison of isotherm models

Journal of Hazardous Materials, 2006

In this study, the potential of activated carbon for phenol adsorption from aqueous solution was studied. Batch kinetics and isotherm studies were carried out to evaluate the effect of contact time, initial concentration, and desorption characteristics of activated carbon. The equilibrium data in aqueous solutions was represented by the isotherm models. Desorption studies to recover the adsorbed phenol from activated carbon performed with NaOH solution. It is necessary to propose a suitable model to gain a better understanding on the mechanism of phenol desorption. For this purpose, pore diffusion and first-order kinetic models were compared. The diffusivity rate (D/r 2 ) and first-order desorption rate (k D ) constants were determined as 6.77 × 10 −4 and 3.924 × 10 −4 s −1 , respectively. The two-and three-parameter in the adopted adsorption isotherm models were obtained using a non-linear regression with the help of MATLAB ® package program. It was determined that best-fitted adsorption isotherm models were determined to be in the order: Langmiur > Toth > Redlich-Peterson > Freundlich isotherms.

Adsorption of Phenol from Aqueous Solution by Avocado Seed Activated Carbon: Equilibrium, Kinetic, and Full Factorial Design Analysis

Activated carbon from avocado (Persea Americana) seeds, obtained by chemical activation using H 3 PO 4 acid i.e. avocado seed activated carbon (ASAC) was used for the removal of phenol from aqueous solution. Samples were characterized by FTIR, Boehm, pHpzc, iodine number, surface area, and proximate analysis. Batch adsorption studies were performed in order to evaluate the maximum adsorption capacity of phenol by ASAC at 27 o C. optimal conditions from equilibrium studies stood at: adsorbent dose of 1g, pH of 7 and contact time of 120 min for all the different initial concentrations of adsorbate used. The Langmuir isotherm model best represented the equilibrium data with monolayer adsorption capacities of 7.94 mg/g, 15.36 mg/g, and 19.79 mg/g respectively for 100ppm, 200ppm, and 300ppm initial adsorbate concentrations. Kinetic studies revealed that the adsorption process followed a pseudo-second order model and the mechanism of the sorption process is controlled by film diffusion of the adsorbate into the adsorbent. In order to examine the main factors (pH, adsorbent dosage and contact time) and their interactions for the uptake of phenol, a 2 3 full factorial design was used. The optimization of factors to obtain maximum adsorption was carried out by using main factors and their interactions, normal probability plot, Analysis of Variance (ANOVA) and Pareto chart.

Kinetics and equilibrium studies of adsorption of phenol in aqueous solution onto activated carbon prepared from rice and coffee husks

Abstract— Activated carbons obtained from the chemical activation of rice and coffee husks using H3PO4 were used to remove phenol from aqueous solution. Batch adsorption experiments were carried out and the amount of phenol adsorbed was determined as a function of adsorption time, pH of solution, adsorbent mass and initial concentration of phenol. The activated carbon used as adsorbent was characterized for its moisture content, bulk density, CHNS analysis, pH of zero point charge (pHpcz) and pH of the phenol solution. Some kinetics parameters were calculated; from kinetic results, the initial rate (obtained by pseudo second order) of adsorption is greater for all the adsorbent. The applicability of pseudo-second order model showed that the rate limiting step was chemisorption, involving forces caused by sharing or exchange of electrons between sorbent and sorbate. An Equilibrium study of the adsorption process showed that Langmuir isotherm described the isotherm data with high correlation coefficients on CAH2 and CAMH, while that of Temkin described that on CAH1. The values of energy obtained from the Temkin isotherm are also positive, this show that the adsorption process is exothermic. The results indicate that chemical rice husk and coffee husk activated carbon is suitable to be used as an adsorbent for phenol adsorption from aqueous solutions.

Removal of phenol from aqueous solution by Mahua seed activated carbon: Kinetic, isotherm, mass transfer and isosteric heat of adsorption studies

Chemical Industry and Chemical Engineering Quarterly, 2016

Mahua (Madhuca longifolia) seed activated carbon (MSAC) has been developed as an effective adsorbent for the removal of phenol from contaminated wastewaters. Prepared MSAC was characterized for various physico-chemical properties, Fourier transform infra- red (FTIR) and scanning electron microscopy (SEM) analysis. Laboratory batch experiments were performed to investigate the effect of MSAC dosage (w), pH, contact time (t), and initial phenol concentrations (Co) on sorption efficiency at optimal conditions. The maximum adsorption capacity of phenol was obtained at pH=6, t=5 h and MSAC dosage=1.2 g/l. The kinetics data of phenol adsorption was very well described by the pseudo-second-order kinetic model. The equilibrium adsorption data were best fitted to the Langmuir isotherm. The average effective diffusion coefficient 6.4?10-13 m2/s was calculated from the experimental data. Thermodynamic studies confirmed the sorption process to be spontaneous and exothermic. The isosteric heat o...

Kinetics of Phenol Removal from Aqueous Solution by Adsorption onto Peanut Shell Acid-activated Carbon

Adsorption Science & Technology, 2005

A pseudo-second-order rate equation describing the kinetic adsorption of phenol onto peanut shell acid-activated carbon at different initial concentrations, carbon dosages and particle sizes has been developed. The adsorption kinetics were followed on the basis of the amount of phenol adsorbed at various time intervals at 22°C. The rate constant and the equilibrium adsorption capacity were calculated. From these parameters, empirical correlations for predicting the equilibrium adsorption capacity as a function of the C 0 /D ratio, and for estimating the rate constant as a function of the relation D/(C 0 d p ) 0.5 , were derived.

Adsorptive removal of phenol from aqueous solutions on activated carbon prepared from tobacco residues: Equilibrium, kinetics and thermodynamics

Journal of Hazardous Materials, 2011

This study consists of producing high surface area activated carbon from tobacco residues by chemical activation and its behavior of phenol removal from aqueous solutions. K 2 CO 3 and KOH were used as chemical activation agents and three impregnation ratios (50, 75 and 100 wt.%) were applied on biomass. Maximum BET surface areas of activated carbons were obtained from impregnation with 75 wt.% of K 2 CO 3 and 75 wt.% of KOH as 1635 and 1474 m 2 /g, respectively. Optimum adsorption conditions were determined as a function of pH, adsorbent dosage, initial phenol concentration, contact time and temperature of solution for phenol removal. To describe the equilibrium isotherms the experimental data were analyzed by the Langmuir, Freundlich, Dubinin-Radushkevich (D-R) and Temkin isotherm models. Pseudo-first order, pseudo-second order and intraparticle diffusion kinetic models were used to find out the kinetic parameters and mechanism of adsorption process. The thermodynamic parameters such as G • , H • and S • were calculated for predicting the nature of adsorption. According to the experimental results, activated carbon prepared from tobacco residue seems to be an effective, low-cost and alternative adsorbent precursor for the removal of phenol from aqueous solutions.

Adsorption of Phenol on Granular Activated Carbon from Nutrient Medium:Equilibrium and kinetic Study

International Journal of Environmental Research, 2009

This paper presents the adsorption of phenol on granular activated carbon (GAC) from nutrient medium suitable for roorganisms’ growth and also the subsequent biodegradation. Two parameter Langmuir and Freundlich adsorption isotherm models were studied using large range of phenol concentration (50-1000 mg/L). In low range of phenol concentration (50-300 mg/L), correlation coefficient, normalized deviation “g% and separation factor were 0.9989, 2.18% and 0.38- 0.78 respectively, while for higher concentration range (400-1000 mg/L), the corresponding values were 0.9719, 1.9% and 0.45- 0.67. Freundlich isotherm gave correlation coefficient of 0.9984, 1/n. value of 0.7269 and normalized deviation of 4.55%. Comparison based on R2, adjusted R2, normalized deviation and root mean square deviation (RMSD) showed that the Redke-Prausnitz isotherm model gives better prediction compared to other models. Adsorption of phenol follows pseudo second order kinetics with correlation coefficient cl...

Liquid Phase Adsorption of Phenol by Activated Carbon Derived From Hazelnut Bagasse #

Wastewater containing phenolic compounds presents a serious discharge problem due to their poor biodegradability, high toxicity and ecological aspects. In this study, the adsorption of phenol from aqueous solution on activated carbon obtained from hazelnut bagasse activated with ZnCl 2 was investigated. Batch adsorption experiments were carried out at constant pH value under varying experimental conditions of contact time, phenol concentration, temperature and adsorbent dose. Adsorption equilibrium was reached within 300 min. Studies showed that the removal efficiency of phenol increased with increase in adsorbent dose and phenol concentration. Temperature was not affected significantly phenol removal. Freundlich and Langmuir adsorption isotherms were applied to the experimental data. Both the Freundlich and Langmuir isotherm models adequately fit to the adsorption data for all temperatures. The adsorption capacities calculated from Langmuir equation were found to be 97.36, 91.32 and 99.27 mg/g for 25, 35 and 45 o C, respectively. The adsorption kinetics were examined at three different phenol concentrations (300, 400 and 600 mg/L). The kinetic models such as pseudo first order and pseudo second order model were fitted to identify the mechanism of adsorption process; the adsorption of phenol obeyed pseudo second order rate equation for all concentration range. The present study shows that the activated carbon derived from hazelnut bagasse can be used as low-cost adsorbent for adsorption of phenol.

Adsorption of phenol onto Banana Peels Activated Carbon

KSCE Journal of Civil Engineering, 2016

The present paper reports adsorption of phenol onto Banana Peels Activated Carbon (BPAC). The effect of adsorbent dose (m), initial pH (pH 0 ), contact time (t), initial phenol concentration (C o ) and temperature (T) on the adsorption of phenol has been studied using batch experiments. The study revealed that about 83% phenol gets removed at an initial concentration of 50 mg/l, whereas the removal is 60% at an initial concentration of 500 mg/l. The phenol uptake of 6.98 and 48.58 mg per gram of BPAC at respective concentrations was found at an optimum dose of 6 g/l at 303 K. The optimum pH and contact time were found to be 6 and 60 minutes respectively. The pseudo second order kinetic model found best representing the kinetic study. Toth and Redlich-Peterson models were found best suited for describing the adsorption equilibrium data. From thermodynamic study it is confirmed that, phenol adsorption decreases with increase in temperature and is spontaneous and exothermic in nature.

Study on Phenol Adsorption by Activated Carbon Derived from Coconut Shell

In the present study, adsorption of phenol from synthetic wastewater was investigated on metal impregnated activated carbon derived from coconut shell. Carbonized coconut shell mixed with appropriate metal salts was pyrolyzed at 850°C under inert N2 atmosphere to develop metal impregnated activated carbon. In order to evaluate the performance of activated carbon thus prepared batch adsorption experiments were conducted at a fixed temperature (27°C) and pH (6.0) for different initial phenol concentration ranging from 100 to 500 mg.l-1, with adsorbent loading of 0.2 gm in 200 ml adsorbate solution. The maximum adsorption capacity was found to be highest for 1% Zn-2% Fe-AC which was as high as 402 mg.g-1. The adsorption isotherms were in conformation to both Langmuir and Freundlich isotherm model. Kinetic evaluation indicated that phenol adsorption on developed activated carbon followed pseudo-second-order rate reaction. Diffusion controlled kinetic model on the system showed that removal rate was controlled not only by intra-particle diffusion but also film diffusion.