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Advances in Environmental Research Volume 3, Number 2, June 2014 , pages 131-149 DOI: https://doi.org/10.12989/aer.2014.3.2.131 |
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Discrimination of rival isotherm equations for aqueous contaminant removal systems |
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Khim Hoong Chu
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| Abstract | ||
| Two different model selection indices, the Akaike information criterion (AIC) and the coefficient of determination (R2), are used to discriminate competing isotherm equations for aqueous pollutant removal systems. The former takes into account model accuracy and complexity while the latter considers model accuracy only. The five types of isotherm shape in the Brunauer-Deming-Deming-Teller (BDDT) classification are considered. Sorption equilibrium data taken from the literature were correlated using isotherm equations with fitting parameters ranging from two to five. For the isotherm shapes of types I (favorable) and III (unfavorable), the AIC favors two-parameter equations which can easily track these simple isotherm shapes with high accuracy. The R2 indicator by contrast recommends isotherm equations with more than two parameters which can provide marginally better fits than two-parameter equations. To correlate the more intricate shapes of types II (multilayer), IV (two-plateau) and V (S-shaped) isotherms, both indices favor isotherm equations with more than two parameters. | ||
| Key Words | ||
| adsorption isotherm; Akaike information criterion; equilibrium data; modeling | ||
| Address | ||
| Honeychem, Nanjing Chemical Industry Park, Nanjing 210047, China. | ||
