Separation of light hydrocarbons with ionic liquids: A review

doi:10.1016/j.cjche.2019.01.012

Abstract

Abstract: Light hydrocarbons (C₁-C₄) are fundamental raw materials in the petroleum and chemical industry. Separation and purification of structurally similar paraffin/olefin/alkyne mixtures are important for the production of highpurity or even polymer-grade light hydrocarbons. However, traditional methods such as cryogenic distillation and solvent absorption are energy-intensive and environmentally unfriendly processes. Ionic liquids (ILs) as a new alternative to organic solvents have been proposed as promising green media for light hydrocarbon separation due to their unique tunable structures and physicochemical properties resulting from the variations of the cations and anions such as low volatility, high thermal stability, large liquidus range, good miscibility with light hydrocarbons, excellent molecular recognition ability and adjustable hydrophylicity/hydrophobicity. In this review, the recent progresses on the light hydrocarbon separation using ILs are summarized, and some parameters of ILs that influence the separation performance are discussed.

Key words: Ionic liquids, Hydrocarbons, Absorption, Sepatation, Solubility

摘要： Light hydrocarbons (C₁-C₄) are fundamental raw materials in the petroleum and chemical industry. Separation and purification of structurally similar paraffin/olefin/alkyne mixtures are important for the production of highpurity or even polymer-grade light hydrocarbons. However, traditional methods such as cryogenic distillation and solvent absorption are energy-intensive and environmentally unfriendly processes. Ionic liquids (ILs) as a new alternative to organic solvents have been proposed as promising green media for light hydrocarbon separation due to their unique tunable structures and physicochemical properties resulting from the variations of the cations and anions such as low volatility, high thermal stability, large liquidus range, good miscibility with light hydrocarbons, excellent molecular recognition ability and adjustable hydrophylicity/hydrophobicity. In this review, the recent progresses on the light hydrocarbon separation using ILs are summarized, and some parameters of ILs that influence the separation performance are discussed.

关键词: Ionic liquids, Hydrocarbons, Absorption, Sepatation, Solubility

Yuqi Huang, Yuanbin Zhang, Huabin Xing. Separation of light hydrocarbons with ionic liquids: A review[J]. Chinese Journal of Chemical Engineering, 2019, 27(6): 1374-1382.

Yuqi Huang, Yuanbin Zhang, Huabin Xing. Separation of light hydrocarbons with ionic liquids: A review[J]. 中国化学工程学报, 2019, 27(6): 1374-1382.

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