摘要
综合考虑缔合作用和密度涨落的影响,将经重整化群修正的CPA方程(RG-CPA方程)扩展到二元体系汽液相平衡的计算。通过一个温度下的汽液相平衡数据回归得到二元交互作用参数,预测其他温度下的相平衡。采用这种方法计算了超临界CO2与醇二元体系的汽液相平衡性质和临界曲线。结果表明,RG-CPA方程预测超临界CO2与醇二元体系的气液相组成和密度具有较高的精度,液相组分平均绝对偏差为0.032,气相组分平均绝对偏差为0.019。与原始CPA方程相比,RG-CPA方程能更好地预测气液临界曲线。
Considering the contribution of association and the density fluctuations,an equation of state（EOS）based on the original cubic-plus-association（CPA）EOS and the renormalization group theory（RG）was extended to binary mixtures.The binary interaction parameters were obtained by fitting the vapor-liquid equilibrium（VLE）data at one temperature,and then were used to predict the VLE data at other temperatures.The RG-CPA EOS was used to predict the VLE and the critical line of the supercritical CO2-1-alkanol（n=1—8）binary mixtures,which are nonideal systems with association.Using temperature independent binary interaction parameters,satisfactory results for composition and density of both vapor and liquid phases were obtained by the RG-CPA EOS.The overall average absolute derivations of composition in liquid and vapor were 0.032 and 0.019 respectively.In addition,the RG-CPA EOS can successfully reproduce the vapor liquid critical line of these binary mixtures,which is much better than the original CPA EOS.
出处
《化工学报》
EI
CAS
CSCD
北大核心
2012年第5期1331-1337,共7页
CIESC Journal
基金
国家重点基础研究发展计划项目(2009CB219805)
国家自然科学基金项目(51076074)~~
关键词
汽液相平衡
超临界CO2
缔合
重整化群
vapor-liquid equilibrium
supercritical CO2
association
renormalization group
