Entropy of Mixing of Triglycerides Oil

Abstract

Using the model of the perfect solutions or the regular solutions, mathematical equations were derived for the approximation of the entropy of mixing of triglyceride oils, or fatty oil that is the solution of multicomponent of triglyceride species.
The molar entropy of mixing of triglyceride oils entirely depends upon the triglyceride structures; namely, the equations derived for mono acid structure (s_O), 1-random-2-random-3-random (s_P), 1, 3-random-2-random (s_Q) and 1, 2, 3-random (s_R) are respectively as follows;
s_O=-RnΣJw_Jlnw_J
s_P=-R3ΣinΣJx_{J, i}lnx_{J, i}
s_Q=-R {nΣJ (3w_J-x_{J, 2}) ln (3w_J-x_{J, 2}/2) +nΣJx_{J, 2}lnx_{J, 2}}
s_R=-3RnΣJw_Jlnw_J
where R is the gas constant, w_J and x_{J, i} are mole fractions of acid radical A_J (J=1, 2, …, n) in total fatty acid composition and in i- (i=1, 2, 3) position respectively.
The increase of entropy of mixing and the free energy change as the regular solution in mixing of different kinds of triglyceride oils were also calculated by assuming that the structure of these oils is 1-random-2-random-3-random distribution.