Economically Viable Process for Synthesizing and Purifying Ionic Liquids: 1‑Butyl-3-methyl Imidazolium Tetrafluoroborate

• Published in: Industrial & engineering chemistry research 2024-06, Vol.63 (23), p.10373-10379
• Main Authors: Choi, Myungho, Lim, Jungae, Kwon, Sunil, Jeong, Kwanyong, Park, Ji Hoon, Byun, Jaewon, Kim, Soo Min, Han, Jee-hoon
• Format: Article
• Language: English
• Subjects: Process Systems Engineering
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.4c01218

Ionic liquids (ILs) have been utilized in a variety of applications owing to their nonflammability, low volatility, and tunable chemical properties. However, removing impurities during the synthesis process is complex and costly. In this work, we introduce a novel and cost-effective method to purify [bmim]­[BF4], an IL, by inducing phase separation using a halocarbon refrigerant such as chlorodifluoromethane (Rf-22). The technique utilizes a ternary phase diagram consisting of [bmim]­[BF4], water, and halocarbons to achieve a purity greater than 99% and simplify the purification process. Large-scale process simulations based on experimental data were performed using the ASPEN Plus process simulator. The minimum [bmim]­[BF4] sales price of the developed process was estimated to be $12,004 per metric ton, making it an economically viable option for [bmim]­[BF4] production.