Next Article in Journal
Predicting BOD under Various Hydrological Conditions in the Dongjin River Basin Using Physics-Based and Data-Driven Models
Previous Article in Journal
Small Catchment Runoff Sensitivity to Station Density and Spatial Interpolation: Hydrological Modeling of Heavy Rainfall Using a Dense Rain Gauge Network
Article

Adsorption of Azo-Anionic Dyes in a Solution Using Modified Coconut (Cocos nucifera) Mesocarp: Kinetic and Equilibrium Study

1
Process Design and Biomass Utilization Research Group (IDAB), Chemical Engineering Department, University of Cartagena, Avenida del Consulado St. 30, Cartagena de Indias 130015, Colombia
2
Nanomaterials and Computer Aided Process Engineering Research Group (NIPAC), Chemical Engineering Department, University of Cartagena, Avenida del Consulado St. 30, Cartagena de Indias 130015, Colombia
*
Author to whom correspondence should be addressed.
Academic Editor: Cidália Botelho
Water 2021, 13(10), 1382; https://doi.org/10.3390/w13101382
Received: 5 April 2021 / Revised: 6 May 2021 / Accepted: 13 May 2021 / Published: 15 May 2021
(This article belongs to the Section Wastewater Treatment and Reuse)
The effect of adsorbent dose and initial concentration on removing the azo-anionic dyes Congo Red andtartrazine present in a synthetic aqueous solution was studied using natural cellulose (CC) and modified cationic cellulose (MCC) from coconut mesocarp. Three levels of adsorbent dosage (5, 8 and 12 mg/L) and initial concentration (40, 70 and 100 mg/L) were used. Cetyl trimethyl ammonium chloride (CTAC) was used as a modifying agent. TGA and DSC showed that the extracted cellulose was of good quality, composed mostly of cellulose with lignin and hemicellulose traces, and 8% moisture. The FTIR spectrum showed the effectiveness of the modification in the structure of the material with symmetric deformation of the C6H6-Cl group in 1472 cm−1 present in the CTAC. It was found that decreasing the adsorbent dosage and increasing the initial concentration favored the dyes’ adsorption capacity on the two bioadsorbents. Tartrazine removals of 5.67 mg/g on CC and 19.61 mg/g on MCC were achieved, and for CR of 15.52 mg/g on CC and 19.99 with MCC with removal percentages over 97% with the quaternized biomass in all cases. The kinetic and equilibrium study was carried out to identify the mechanisms involved in the adsorption process. The Freundlich model can describe the equilibrium isotherm data of tartrazine on CC and MCC. In contrast, those of CR is defined by the Langmuir and Dubinin–Radushkevic models for CC and MCC, respectively Adsorption kinetics showed that equilibrium was reached at 30 min, with rapid adsorption in the initial minutes with the removal of about 97% of the contaminant in the first 5 min; fitting to kinetic models showed that the kinetics of tartrazine on CC was fitted by Elovich (R2 = 0.756), and on MCC the Elovich (R2 = 0.887) and pseudo-second-order (R2 = 0.999) models. Removing CR on CC was fitted by pseudo-first-order, pseudo-second-order and Elovich models (R2 > 0.98), and when using MCC, all models show a good fitting with R2 = 0.99 in all cases. View Full-Text
Keywords: adsorption; cellulose; quaternization; tartrazine; Congo red adsorption; cellulose; quaternization; tartrazine; Congo red
Show Figures

Figure 1

MDPI and ACS Style

Tejada-Tovar, C.; Villabona-Ortíz, Á.; Gonzalez-Delgado, Á.D. Adsorption of Azo-Anionic Dyes in a Solution Using Modified Coconut (Cocos nucifera) Mesocarp: Kinetic and Equilibrium Study. Water 2021, 13, 1382. https://doi.org/10.3390/w13101382

AMA Style

Tejada-Tovar C, Villabona-Ortíz Á, Gonzalez-Delgado ÁD. Adsorption of Azo-Anionic Dyes in a Solution Using Modified Coconut (Cocos nucifera) Mesocarp: Kinetic and Equilibrium Study. Water. 2021; 13(10):1382. https://doi.org/10.3390/w13101382

Chicago/Turabian Style

Tejada-Tovar, Candelaria, Ángel Villabona-Ortíz, and Ángel D. Gonzalez-Delgado 2021. "Adsorption of Azo-Anionic Dyes in a Solution Using Modified Coconut (Cocos nucifera) Mesocarp: Kinetic and Equilibrium Study" Water 13, no. 10: 1382. https://doi.org/10.3390/w13101382

Find Other Styles
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop