Effect of strong electrolytes on edible oils part 1: viscosity of sunflower oil in 1,4-dioxane at different temperatures

Abstract

The viscosity of sunflower oil in 1,4-dioxane used as a diluent in the presence and absence of strong electrolytes (HCl, NaOH, NaCl) at different temperatures (298K to 323K) was accomplished. The viscosity of sunflower oil was found to increase with the increasing concentration and decreased with the increase in temperature. It was further observed that viscosity of sunflower solution in 1,4-dioxane increases under the influence of electrolytes. The values of Jones-Dole coefficient A and B were evaluated. The positive values of B-coefficient increased with the rise of temperature. This led to conclusion that ion-solvent interactions increase and electrolytes such as HCl, NaOH and NaCl behave as structure breaker in sunflower-1,4-dioxane system. The change in the values of fluidity parameters such as (a, k, α₁, α₂, β, β *) with concentration of oil and temperature suggests that fluidity parameters are structural. The energy of activation (ΔE_v), latent heat of vapourization (ΔL_v) and molar volume of oil (V_m) were also calculated. Effect of electrolytes show that, the concentration of electrolytes increases the value of (ΔE_v) and (ΔL_v) whereas the value of molar volume (V_m) decrease with the concentration of oil and electrolytes. In brief, unsaturations of fatty acids of oil are responsible for the changes in the values of different parameters determined. The results for (ΔE_v) and (ΔL_v) are influenced by the concentration of sunflower oil.


Journal of Applied Sciences and Environmental Management Vol 9(2) 2005: 15-21