Solid–Liquid Equilibria and Characterization of the Reaction Mixture To Produce Sucrose Palmitate in Solvent-Free Media

Abstract

This work deals with the characterization of the reactive mixtures involved in the production of sucrose palmitate from methyl palmitate and sucrose, through a solvent-free process. The solid–liquid equilibrium in mixtures of sucrose–methyl palmitate–sucrose palmitate (SE) at temperatures between 363 and 403 K and sucrose ester concentrations between 0 and 15 g SE/100 g methyl palmitate was measured. Solid and liquid heat capacities of sucrose palmitate and thermal properties useful in the equilibrium modeling were measured through differential scanning calorimetry and thermogravimetric analysis. The viscosity and surface tension of the reaction product were also measured. According to results sucrose palmitate melts at 315.82 K and decomposes at 510.67 K. The average solid and liquid heat capacities of sucrose ester in the evaluated ranges were 2010 J/kg·K and 2475 J/kg·K, respectively. The predictive modified UNIFAC method for sugars (mS-UNIFAC) and the nonrandom two-liquid equation were used to model the solid–liquid equilibria, and their performance was compared with the extrapolation of an empirical linear model. Models agree well with experiments, and together with the obtained physicochemical properties, they can be used for further process design in the synthesis of sucrose esters.

Reactive Distillation of Glycolic Acid Using Heterogeneous Catalysts: Experimental Studies and Process Simulation

“…The solid–liquid equilibrium is widely used in the literature to determine the activity coefficients of a solute ( Negadi et al, 2006 ; Gutiérrez et al, 2019 ). For GA as solute, the equilibrium equation can be expressed as follows: , , and are respectively the activity, molar fraction, and activity coefficient of glycolic acid in saturated solution.…”

Solvent-Free Synthesis of High-Purity Sucrose Fatty Acid Monoesters and a Comparison of Their Properties with Those of Their Commercial Counterparts

“…However, due to the immiscibility of the starting materials required for synthetic production, solvent-free methods frequently suffer from long reaction times, poor yields, and the formation of impure products . Potential solutions to these deficiencies have been reported and include employing sand-milling pretreatment, co-melting, ultrasonic irradiation, heterogeneous base catalysis, and the addition of surfactants. − Although such modifications have improved the yields of the target SEs, to the best of our knowledge, no protocol that can simultaneously generate sucrose monoesters in high purity (∼70%) and practically useful yields (∼50%) has been reported. The work we report here addresses this deficiency.…”