Adsorption of Dyes from Aqueous Solutions on Activated Charcoal

Department of Chemistry, Quaid-i-Azam University, Islāmābād, Islāmābād, Pakistan
Journal of Hazardous Materials (Impact Factor: 4.53). 02/2007; 139(1):57-66. DOI: 10.1016/j.jhazmat.2006.06.007
Source: PubMed


Adsorption of industrially important dyes namely bromophenol blue, alizarine red-S, methyl blue, methylene blue, eriochrome black-T, malachite green, phenol red and methyl violet from aqueous media on activated charcoal has been investigated. The effect of shaking time, pH and temperature on the adsorption behaviour of these dyes has been studied. It was noted that adsorption of all the dyes on activated charcoal decreases with an increase in the pH and the temperature. The adsorption isotherms at different temperatures were found to be of L-type. Adsorption data was fitted to Freundlich, BET and Langmuir isotherms and various adsorption parameters have been calculated. The thermodynamic parameters such as DeltaG, DeltaH and DeltaS were calculated from the slopes and intercepts of the linear variation of lnK against 1/T, where K is the adsorption coefficient obtained from Langmuir equation, was used. The calculated values for the heat of adsorption and the free energy indicate that adsorption of dyes is favored at low temperatures and the dyes are chemisorbed on activated charcoal.

    • "Turabýk and Gozmen, (2013) Shanthi and Mahalakshmi, (2012) Kurniawan et al., (2012) Cheknane et al., (2010) Chan et al., (2009) Shen et al., (2009) Kang et al., (2009) Noroozi et al., (2008) Turabik, (2008) Ong et al., (2007) Iqbal and Ashiq, (2007) Chakraborty et al., (2006) Allen et al., (1988) "
    [Show abstract] [Hide abstract]
    ABSTRACT: Water plays a vital and essential role in our ecosystem. This natural resource is becoming scarce, making its availability a major social and economic concern. Use of a large variety of synthetic dyes in textile industries has raised an hazardous environmental alert. About 17 - 20% of freshwater pollution is caused by textile effluents. These effluents are recalcitrant to biodegradation and cause acute toxicity to the receiving water bodies, as these comprised of various types of toxic dyes, which are difficult to remove. Decolorisation of textile wastewater is therefore important before releasing it into the nearby local waterways. It therefore becomes essential to degrade the toxic chemicals of textile wastewater, so as to avoid the hazardous environmental effects. Several treatment methods have been employed to embark upon the problem of dye removal but degradation becomes further more difficult for effluents containing dye matrix. The review study has been an attempt to present the different diversified attempts used for decolorisation of a mixture of dyes.
    No preview · Article · Jan 2015 · Global Journal of Environmental Science and Management
  • Source
    • "The authors note that correlation coefficients are highest for Ho's pseudo-second-order equation, which suggests that this model is best suited to predicting the kinetics of the MB adsorption onto MKP cokes. Assuming there is an exchange of electrons between MB molecules and adsorbent through covalent forces, the adsorption process can be described as chemisorption (Iqbal and Ashiq, 2006; Vadivelan and Kumar, 2005), although the thermodynamic studies strongly suggest that the adsorption process is physisorption. "
    [Show abstract] [Hide abstract]
    ABSTRACT: Effect of the initial dye concentration, contact time, pH, adsorbent quantity, and temperature on the adsorption of the cokes was investigated for methylene blue adsorption of the cokes obtained from pyrolysis of Mustafa Kemal Pasa lignite. The maximum amount of dye adsorbed was 270 mg/g. Equilibrium of the adsorption was examined by Langmuir and Freundlich isotherms. The pseudo-first-order, pseudo-second-order, and intra-particle diffusion models described the adsorption kinetics. The adsorption equilibrium was well described by Langmuir and Freundlich isotherms. The adsorption kinetics fit well to the Ho's pseudo-second-order model. The cokes are highly favorable adsorbents for the removal of methylene blue from aqueous media.
    Full-text · Article · Oct 2014 · Energy Sources Part A Recovery Utilization and Environmental Effects
  • Source
    • "The cost effectiveness , availability and adsorptive properties are the main criteria in selection of an adsorbent to remove organic compounds from wastewaters (Demirbas et al., 2008; Ghaedi et al., 2012), also application of adsorption procedure especially based on non-toxic and green adsorbent with high surface area and reactive surface atom is a great demand (Chiou and Chuang, 2006). Activated carbon, a widely used adsorbent in industrial processes, is composed of a microporous, homogenous structure with high surface area and shows radiation stability (Iqbal and Ashiq, 2007). The process for producing high-efficiency activated carbon is not completely investigated in developing countries. "
    [Show abstract] [Hide abstract]
    ABSTRACT: The preparation of activated carbon from coconut husk with H2SO4 activation (CSAC) and its ability to remove textile dyes (Maxilon blue GRL, and Direct yellow DY 12), from aqueous solutions were reported in this study. The adsorbent was characterized with Fourier transform infrared spectrophotometer FT-IR, and scanning electron microscope SEM. Various physiochemical parameters such as, contact time, initial dye concentration, adsorbent dosage, particle size, pH of dye solution and temperature were investigated in a batch-adsorption technique. Result showed that the adsorption of both GRL and DY 12 dyes were favorable at acidic pH. The adsorption uptake was found to increase with increase in initial dye concentration, and contact time but decreases with the amount of adsorbent, particle size, and temperature of the system. The Chemisorption, intra-particle diffuse, pseudo-first-order and pseudo-second-order kinetic models were applied to test the experimental data. The pseudo-second order exhibited the best fit for the kinetic studies, which indicates that adsorption of (GRL, and DY12) is limited by chemisorption process. The equilibrium data was evaluated using Langmuir, Freundlich, Temkin and Fritz-Schluender isotherms. The Fritz - Schluender model best describes the uptake of (GRL and DY 12) dye, which implies that the adsorption of textiles dyes in this study onto coconut husk activated carbon is heterogeneous with multi-layers. Thermodynamic parameters such as Gibbs free energy, enthalpy and entropy were determined. It was found that (GRL and DY 12) dye adsorption was spontaneous and endothermic.
    Full-text · Article · Feb 2014 · Arabian Journal of Chemistry
Show more