Solid-liquid equilibrium of triolein with fatty alcohols

Abstract

-Triacylglycerols and fatty alcohols are used in the formulation of cosmetic, pharmaceutical and food products. Although information about the phase transitions of these compounds and their mixtures is frequently required for design and optimization of processes and product formulation involving these substances, these data are still scarce in the literature. In the present study, the solid-liquid phase diagrams of two binary systems composed of triolein + 1-hexadecanol and triolein + 1-octadecanol were evaluated by differential scanning calorimetry (DSC) and optical microscopy. The experimental data were compared with predicted data by solving the phase equilibrium equations using an algorithm implemented in MATLAB. The liquid-phase activity coefficients were calculated using the Margules equation (two-and three-suffix) and the UNIFAC model (original and modified Dortmund model). The approaches used for calculating system equilibrium allowed an accurate prediction of the liquidus line with low deviations from the experimental data.

Binary solid–liquid equilibrium systems containing fatty acids, fatty alcohols and triolein by differential scanning calorimetry

“…Except for the thermal curves of pure components, three thermal events can be observed in this system. The first one at the lowest temperature is attributed to b 0 -form crystallization indicated by exothermic peak, the second one, at intermediate temperature, is attributed to [10,11,13]. The increase in molar fraction of triolein causes a gradual decrease of the melting temperature up to reaching the eutectic composition, after the eutectic composition, the melting temperature of the binary mixtures increases again.…”

“…Differential scanning calorimetry (DSC) is a sensitive technique for the detection and evaluation of phase transitions and has been successfully used to study the behavior of (SLE) [3,[10][11][12][13][14][15]. Among the main advantages attributed to this technique, we can cite the use of small amounts of sample (0.1-20 mg), relatively short time of analysis, no special care required with respect the physical state of the sample, and any liquid or solid material can be analyzed with the possibility of application in a wide temperature range with various heating rate programs [16].…”

Thermodynamic Modeling of Multi‐phase Solid–Liquid Equilibria in Industrial‐Grade Oils and Fats

“…The non-linear least squares method objective function was applied [43,44]. The sum of squares of the residuals (SSR) is calculated as shown in Eq.…”

“…In this case, a rather simple parabolic interpolation method is used [44]. This method makes for a fairly transparent approach, where the minimization pathway is easy to monitor and assess.…”

Determinação Experimental Do Equilíbrio Sólido-Líquido De Misturas Binárias De Triacilglicerois Com Ácidos Graxos

“…A Calorimetria Exploratória Diferencial (DSC) é uma técnica sensível para a detecção e avaliação de transições de fase, sendo, com frequência, utilizada no estudo do comportamento do equilíbrio sólido-líquido (Costa et al, 2007;Costa et al, 2009;Costa et al, 2010;Loos et al, 2004;Wei et al, 2012;Maximo et al, 2013). Dentre as principais vantagens atribuídas à técnica pode-se citar a utilização de uma pequena quantidade de amostra (0,1-20 mg), o tempo relativamente curto de análise, a não necessidade de cuidados especiais com a amostra no que diz respeito ao seu estado físico, ou seja, qualquer material líquido ou sólido pode ser analisado com a possibilidade de aplicação de amplas faixas de temperatura com vários programas (taxas) de aquecimento (Afaf e Jan, 2005).…”