New insights from modelling and estimation of mass transfer parameters in fixed-bed adsorption of Bisphenol A onto carbon materials

Abstract Activated carbon (AC) is the most commonly used adsorbent for water purification, although the dispersive nature of AC in aqueous solution poses a serious problem. To overcome this limitation, AC was magnetized with iron oxide using iron salts as precursor. Further to enhance its effectiveness, it was impregnated with Aliquat 336. Different characterization techniques (Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), along with energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD)) were used to analyze the adsorbent. Furthermore, the value of the pH at which the overall charge on the surface of the adsorbent is neutral was found by pH drift method. The modified form of the activated carbon was used to treat the aqueous solution of bisphenol-A in the batch as well as in the continuous mode of operation. In batch mode, the data were validated using equilibrium and kinetic models, and in continuous mode, data were fitted with the Thomas, Adams-Bohart, and bed depth service time (BDST) fixed bed adsorption models. Also, the changes in Gibb's free energy, enthalpy, and entropy were estimated from the temperature study. The design of an adsorption column is proposed to treat 10,000 L/day of an industrial effluent containing BPA.

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Dynamic modeling of fixed-bed adsorption of flue gas using a variable mass transfer model

Korean Journal of Chemical Engineering ◽

10.1007/s11814-015-0180-1 ◽

2015 ◽

Vol 33 (2) ◽

pp. 438-447 ◽

Cited By ~ 7

Author(s):

Jehun Park ◽

Jae W. Lee

Keyword(s):

Mass Transfer ◽

Dynamic Modeling ◽

Flue Gas ◽

Variable Mass ◽

Fixed Bed ◽

Transfer Model ◽

Mass Transfer Model ◽

Fixed Bed Adsorption

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Fixed-bed adsorption of Bisphenol A onto organoclay: characterization, mathematical modelling and theoretical calculation of DFT-based chemical descriptors

Journal of Environmental Chemical Engineering ◽

10.1016/j.jece.2021.106103 ◽

2021 ◽

pp. 106103

Author(s):

M.B. de Farias ◽

M.P. Spaolonzi ◽

M.G.C. Silva ◽

M.G.A. Vieira

Keyword(s):

Bisphenol A ◽

Mathematical Modelling ◽

Theoretical Calculation ◽

Fixed Bed ◽

Fixed Bed Adsorption ◽

Chemical Descriptors

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Breakthrough analysis for hexavalent chromium removal from drinking water in a fixed bed column

Water Science & Technology Water Supply ◽

10.2166/ws.2009.714 ◽

2009 ◽

Vol 9 (6) ◽

pp. 661-670 ◽

Cited By ~ 2

Author(s):

S. P. Dubey ◽

K. Gopal

Keyword(s):

Aqueous Solution ◽

Hexavalent Chromium ◽

Fixed Bed ◽

Entropy Change ◽

Spectroscopic Technique ◽

Fixed Bed Column ◽

Chromium Vi ◽

Fixed Bed Adsorption ◽

Optimal Column ◽

Eucalyptus Bark

The activated carbon of Eucalyptus globulus was tested for their effectiveness in removing hexavalent chromium from aqueous solution using column experiments. Result revealed that adsorption of chromium(VI) on eucalyptus bark carbon was endothermic in nature. Thermodynamic parameters such as the entropy change, enthalpy change and Gibbs free energy change were found to be 1.39 kJ mol−1 K−1, 1.08 kJ mol−1 and −3.85 kJ mol−1, respectively. Different chromium concentrations were used for the fixed bed adsorption studies. The pre- and post-treated adsorbents were characterized using a FTIR spectroscopic technique. It was concluded that Eucalyptus bark carbon column could be used effectively for removal of hexavalent chromium from aqueous solution at optimal column conditions. This study showed that this biological material is potential adsorbent of Cr(VI) from water.

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Modeling of aerated upflow fixed bed reactors for nitrification

Water Science & Technology ◽

10.2166/wst.1999.0193 ◽

1999 ◽

Vol 39 (4) ◽

pp. 85-92 ◽

Cited By ~ 7

Author(s):

J. Behrendt

Keyword(s):

Mathematical Model ◽

Mass Transfer ◽

Liquid Phase ◽

Gas Phase ◽

Fixed Bed ◽

Fixed Bed Reactor ◽

Bulk Liquid ◽

Initial Value ◽

Fixed Bed Reactors ◽

Number Of Cells

A mathematical model for nitrification in an aerated fixed bed reactor has been developed. This model is based on material balances in the bulk liquid, gas phase and in the biofilm area. The fixed bed is divided into a number of cells according to the reduced remixing behaviour. A fixed bed cell consists of 4 compartments: the support, the gas phase, the bulk liquid phase and the stagnant volume containing the biofilm. In the stagnant volume the biological transmutation of the ammonia is located. The transport phenomena are modelled with mass transfer formulations so that the balances could be formulated as an initial value problem. The results of the simulation and experiments are compared.

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