Structure optimization of tailored ionic liquids and process simulation for shale gas separation

Shale gas, as a potential substitute for energy source, requires important processing steps before utilization. The most common separation technology applied is distillation, which is energy‐intensive. With good stability, non‐volatility, and tailored properties, ionic liquids (ILs) are regarded as novel potential solvents and alternative media for gas absorption. Therefore, a new strategy for hybrid shale gas separation processing, where IL‐based absorption together with distillation is employed for energy‐efficient and cost‐economic gas processing, is developed. In this work, a three‐stage methodology for shale gas separation process is proposed: IL screening, where a systematic screening method with two options (database screening and computer‐aided design based on universal quasichemical functional‐group activity coefficient model) is established; suitable ILs are selected as promising candidates; process design and simulation, where separation schemes and important design issues in the IL‐based processes are determined; and, process evaluation, where the performance of the final separation process is evaluated and verified.