Entrainer selection for the extractive distillation of acrylic acid and propionic acid

A combination of molecular modelling and experiments was conducted to study the separation acrylic acid propionic through extractive distillation with polar aprotic entrainers. It found that can be efficiently separated a entrainer, resulting in entrainment making most volatile compound. Vapour-liquid equilibrium were 25 wt% acid, propionic, 50% entrainer. Dimethyl sulfoxide (DMSO) induce highest relative volatility 1.56 at mbar, which agrees well predicted value 1.66 using simulation software COSMO-RS. The difference pKa (ΔpKa = 0.63) between is main cause for enhanced volatility. corresponding hydrogen bonding strength calculated COSMO-RS result ΔE 1.8 kJ/mol °C total mixture. When dodecane selected as an became compound instead acid. This explained by fact has two extra atoms available have Van der Waals interaction carbon dodecane. carboxylic acids mixture 1.34 °C. results 0.91, too small exploited process, it concluded this mixture, DMSO best entrainer study.