Application of statistical physics formalism for the modeling of adsorption isotherms of water molecules on the microalgae Spirulina platensis

Drying and storage of water by Spirulina microalgae are among the main uses of Spirulina in food applications. In this work, we are interested in the storage of water by these microalgae. A model based on the statistical physics formalism is one of the supports for imagining the arrangement of water molecules on Spirulina surface. On the basis of this method, we have interpreted, on a microscopic scale, adsorption isotherms of water molecules by the Spirulina biomass at three temperatures (283 K, 293 K and 303 K). We interpret the results of the fit through the parameters involved in the model namely the number of water molecules adsorbed per site n, the receptor sites density D and the energetic parameters e(1w) and e(2w), determined by fitting the experimental adsorption isotherms. Lastly we calculated the thermodynamic functions which govern the adsorption process such as entropy, free enthalpy and internal energy. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.