Protic ionic liquid—2,2,2‐trifluoroacetic acid—methyl trifluoroacetate mixture distillation process

Abstract

AbstractThe work provides experimental data of the methyl trifluoroacetate (MeTFA)—2,2,2‐trifluoroacetic acid (TFA) mixture distillation process in the presence of N‐Methyl‐2‐pyrrolidone (NMP) at atmospheric pressure (99.2 kPa) and within a temperature range of T ≤ 230°C. Forming PIL between TFA and NMP (methylpyrrolidonium trifluoroacetate [HNMP]+[CF3COO]−) leads to a significant volatility increase of the MeTFA relative to TFA. The pure MeTFA was recovered from the MeTFA‐TFA‐[HNMP]+[CF3COO]− mixture in the quantity of 70% from the MeTFA initial mole charge; the total mole recovery was 100%. A significant result of the above experiment is that TFA mole recovery from the MeTFA‐TFA‐[HNMP]+[CF3COO]− mixture within a temperature range of T < 187°C exceeds 96%. The distillation of TFA and NMP mixture at T ≤ 230°C demonstrates strong binding of TFA anion that can be seen from the final liquid phase composition TFA/NMP ≈ 0.53/0.47. At the concentration and the temperature ranges under study, there is no NMP in the vapour phase.