resumo
The present work addresses the modeling of the phase equilibria of several poly(ethylene glycol) mixtures, with different types of solvents, by the soft-SAFT (statistical associating fluid theory) equation of state (EoS). The molecular parameters for poly(ethylene glycol) were obtained as a function of the molecular weight by extrapolation from the first four members of the ethylene glycols series, up to tetraethylene glycol, obtained in a previous work [Pedrosa et al. Ind. Eng. Chem. Res. 2005, 44, 7027]. The parameters for the different solvents were either taken from previous works or fitted for the first time to available vapor-liquid equilibrium data within the soft-SAFT during this work. Their quadrupolar nature was explicitly taken into account. The phase equilibria studied concerns the solubility of gases, such as nitrogen and propane, and vapor-liquid equilibria with both nonassociating solvents, such as benzene, and associating solvents, such as methanol, ethanol, and water. The liquid-liquid equilibria of poly(ethylene glycol) with different solvents, namely, toluene, ethylbenzene, n-propylbenzene, and tert-butyl acetate, were also described using the soft-SAFT EoS. soft-SAFT was able to provide an overall good description of all mixtures investigated here. The advantages and shortcomings of the model as well as its capability to describe the dependence of the phase equilibria with the molecular weight of the polymer are discussed.
palavras-chave
ASSOCIATING FLUID THEORY; DIRECTIONAL ATTRACTIVE FORCES; EQUATION-OF-STATE; THERMODYNAMIC PERTURBATION-THEORY; VAPOR-LIQUID-EQUILIBRIUM; CHAIN MOLECULES; CARBON-DIOXIDE; POLYETHYLENE-GLYCOL; POLYMER-SOLUTIONS; BEHAVIOR
categoria
Engineering
autores
Pedrosa, N; Vega, LF; Coutinho, JAP; Marrucho, IM
nossos autores
