Water adsorption isotherms and thermodynamic properties of cassava bagasse

Author(s)

Polachini, Tiago Carregari ^[1] ; Leonardo Betiol, Lilian Fachin ^[1] ; Lopes-Filho, Jose Francisco ^[1] ; Telis-Romero, Javier ^[1]

Affiliation

^[1] State Univ Sao Paulo, Food Engn & Technol Dept, BR-15054000 Sao Paulo - Brazil

• Document type: Journal article
• Source: Thermochimica Acta; v. 632, p. 79-85, MAY 20 2016.
• Web of Science Citations: 4

Abstract

Losses of food industry are generally wet products that must be dried to posterior use and storage. In order to optimize drying processes, the study of isotherms and thermodynamic properties become essential to understand the water sorption mechanisms of cassava bagasse. For this, cassava bagasse was chemically analyzed and had its adsorption isotherms determined in the range of 293.15-353.15 K through the static gravimetric method. The models of GAB, Halsey, Henderson, Oswin and Peleg were fitted, and best adjustments were found for GAB model with R-2 > 0.998 and no pattern distribution of residual plots. Isosteric heat of adsorption and thermodynamic parameters could be determined as a function of moisture content. Compensation theory was confirmed, with linear relationship between enthalpy and entropy and higher values of isokinetic temperature (T-B =395.62 K) than harmonic temperature. Water adsorption was considered driven by enthalpy, clarifying the mechanisms of water vapor sorption in cassava bagasse. (C) 2016 Elsevier B.V. All rights reserved. (AU)

• FAPESP's process: 13/17497-5 - Determination of the best conditions of physical hydrolysis by power ultrasound in agroindustrial wastes
• Grantee: Javier Telis Romero
• Support Opportunities: Program for Research on Bioenergy (BIOEN) - Regular Program Grants