학술논문
Dyes Removal Using Activated Carbon from Palm Oil Waste with Digital Image Colorimetry Quantification.
Document Type
Article
Source
Subject
*DYES & dyeing
*ACTIVATED carbon
*PALM oil
*SORBENTS
*COLORIMETRY
*THERMODYNAMICS
*ADSORPTION
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Language
ISSN
0094-243X
Abstract
In the present study, activated carbon prepared from palm oil husk was used as adsorbent to remove synthetic dyes of Reactive Red 120 (RR) and Direct Green 26 (DG) from aqueous solution. The effects of solution pH, contact time, adsorbent weight, dyes concentration, and temperature on adsorption were evaluated based on batch experiments along with determination of the adsorption isotherms, kinetics, and thermodynamics parameters. Visible spectrophotometry was used for the quantification of dyes concentration, in conjunction with digital image colorimetry as a novel quantification method. Compared to visible spectrophotometry, the results of digital image colorimetry were accurate. In addition, improved sensitivity was achieved using this new colorimetry method. At equilibrium, dyes adsorption onto activated carbon followed Freundlich model, with adsorption capacities for RR and DG were 32 and 27 mg/g, respectively. The adsorption kinetics study showed a pseudo-second-order model with thermodynamic parameters of ΔG°, ΔH°, and ΔS° were -1.8 to -3.8 kJ/mol, -13.5 to -24.38 kJ/mol, and 0.001 J/mol, respectively. Therefore, the process of adsorption was exothermic and spontaneous with an increase in the disorder or entropy of the system. [ABSTRACT FROM AUTHOR]