**Publish at : ** 01 Jan 2016 - 00:00

**IJtech :** IJtech
Vol 7, No 2 (2016)

**DOI :** https://doi.org/10.14716/ijtech.v7i2.2970

Ismail, A.B.., & Sabnani, K.M..& Ang, L..Ng, K.C.., 2018. An Adsorption Equilibria Model for Steady State Analysis. *International Journal of Technology*. Volume 7(2), pp.274-280

6

Azhar Bin Ismail | Water Desalination and Reuse Center, 4700 King Abdullah University of Science and Technology, Thuwal 23955 6900, Kingdom of Saudi Arabia |

Karan M. Sabnani | Water Desalination and Reuse Center, 4700 King Abdullah University of Science and Technology, Thuwal 23955 6900, Kingdom of Saudi Arabia |

Li Ang | Department of Mechanical Engineering, Faculty of Engineering, National University of Singapore, 9 Engineering Drive 1, Singapore 117576 |

Kim Choon Ng | Water Desalination and Reuse Center, 4700 King Abdullah University of Science and Technology, Thuwal 23955 6900, Kingdom of Saudi Arabia |

Abstract

The investigation of adsorption isotherms is a prime factor in the ongoing development of adsorption cycles for a spectrum of advanced, thermally-driven engineering applications, including refrigeration, natural gas storage, and desalination processes. In this work, a novel semi-empirical mathematical model has been derived that significantly enhances the prediction of the steady state uptake in adsorbent surfaces. This model, a combination of classical Langmuir and a novel modern adsorption isotherm equation, allows for a higher degree of regression of both energetically homogenous and heterogeneous adsorbent surfaces compared to several isolated classical and modern isotherm models, and has the ability to regress isotherms for all six types under the IUPAC classification. Using a unified thermodynamic framework, a single asymmetrical energy distribution function (EDF) has also been proposed that directly relates the mathematical model to the adsorption isotherm types. This fits well with the statistical rate theory approach and offers mechanistic insights into adsorption isotherms.

Adsorption, Energy distribution function, Statistical rate theory, Universal isotherm model

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