Dielectric Properties of Concentration-Dependent Ethanol + Acids Solutions at Different Temperatures

Dielectric properties of ethanol + HCl and ethanol + acetic acid heated at different temperature levels were recorded at microwave frequencies ranging from 0.5 GHz to 6 GHz, and the corresponding dissipation factor and depth of penetration of the solutions were calculated and analyzed using response surface methodology for the factors of temperature level and ethanol and acid (HCl and acetic acid) concentration generated using a central composite design. In case of mixtures with acetic acid, ethanol concentration and temperature were found to be the significant factors; however in the case of mixtures with HCl, HCl concentration was also found to be a significant factor contributing to all analyzed responses. The heating rate was interpreted in terms of the different factors based on their effects on dissipation factor and depth of penetration. Overall, with an increase in the concentration of ethanol and at lower temperature levels, the microwave heating rate was interpreted to be highest at 2.45 GHz. Am...

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