何丽娟¹,杨建滋¹,韩雨泽²,杨文轩¹

• 1:内蒙古科技大学 能源与环境学院， 内蒙古 包头 014010
• 2:桂林理工大学 信息科学与工程学院， 广西 桂林 541006

摘要(Abstract)：

针对二氧化碳-离子液体(CO₂-ILs)体系热力学性质数据较少的问题，采用状态方程+活度系数法（EOS+γ法）计算了CO₂-[C₂-mim][Tf₂N]、CO₂-[C₄-mim][Tf₂N]、CO₂-[C₆-mim][Tf₂N]和CO₂-[C₈-mim][Tf₂N] 4种新型制冷工质对的汽液相平衡数据。在相平衡基础上，通过SRK(Soave-Redlich-Kwong)状态方程+WS(Wong-Sandler)混合规则+UNIFAC活度系数模型，关联得出混合体系的超额吉布斯自由能G^E、超额焓H^E和超额熵S^E。计算结果表明，CO₂-ILs制冷工质对的超额性质均随温度、压力、CO₂液相摩尔分数以及离子液体中阳离子上烷基链长度等因素变化，G^E均为负值，最大值为-1 066.88 J×mol^-1，且G^E随温度、压力和ILs阳离子碳基链长度增大而减小，H^E均为正值，最大值为407.24 J×mol^-1，且H^E随温度、CO₂溶解度及ILs阳离子碳基链长度增大而减小，S^E最大值为7.88 J×mol^-1×K^-1，且S^E随温度和压力的增大而减小、随ILs阳离子碳基链长度增大而增大。根据汽液相平衡时计算的压力平均相对偏差，可证明所选模型在计算CO₂-[C_n-mim][Tf₂N](n=2,4,6,8)系统超额性质的准确性。

关键词(KeyWords)： 汽液相平衡;SRK状态方程;WS混合规则;UNIFAC活度系数模型;超额性质预测

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51566014)；内蒙古自然科学基金(2021MS05035)；内蒙古自治区直属高校基本科技项目。

作者(Author): 何丽娟¹,杨建滋¹,韩雨泽²,杨文轩¹

DOI: 10.3969/j.issn.1003-9015.2024.01.005

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