采用改进Ellis平衡釜测定了α-蒎烯-蒎烷、α-蒎烯-长叶烯、蒎烷-长叶烯三个二元体系及α-蒎烯-蒎烷-长叶烯三元体系常压汽液平衡数据,经Herington规则检验符合热力学一致性。由汽液平衡数据求出每个二元体系中各组分的活度系数,再关联得到相应的过量Gibbs自由能与超额焓实验值。结果表明,α-蒎烯-蒎烷体系的Gibbs自由能对理想溶液呈现较小的正偏差,而α-蒎烯―长叶烯和蒎烷-长叶烯体系Gibbs自由能对理想溶液呈现负偏差。根据Wilson方程对三个二元体系的过量Gibbs自由能和超额焓进行了计算,关联值与实验值吻合,对α-蒎烯-蒎烷体系最大超额焓为120.48 J·mol^-1,α-蒎烯―长叶烯体系最大超额焓为401.09 J·mol^-1,蒎烷-长叶烯体系最大超额焓为685.75J·mol^-1。由关联得到的二元体系能量参数推算了α-蒎烯-蒎烷—长叶烯三元体系的过量Gibbs自由能和超额焓,过量Gibbs自由能的实验值与计算值基本吻合,平均相对偏差为1.7147%,该三元体系的最大超额焓为627.16 J·mol^-1。
The vapor-liquid equilibrium data of α-pinene-pinane, α-pinene-longifolene and pinane-longifolene systems were experimentally determined by a modified Ellis equilibrium method under atmospheric pressure, and these data were found to be thermodynamically consistent with the Herington rules. The results show that the excess Gibbs free energy of the α-pinene–pinane system has slightly positive deviation to ideal solution, while the α-pinene-longifolene and pinane-longifolene systems exhibit negative deviation to ideal solution. Excess Gibbs free energy and excess enthalpy of the three binary systems were correlated by the Wilson equation with good agreement. The α-pinene–pinane system had the maximum excess enthalpy of 120.48J·mol^-1, while that of the α-pinene-longifolene and pinane-longifolene systems were 401.09 J·mol^-1 and 685.75 J·mol^-1, respectively. Meanwhile, the excess Gibbs free energy and excess enthalpy for the ternary system were estimated via the Wilson equation energy parameters of the binary systems, and the calculated excess Gibbs free energy values were in good agreement with the measured values with average relative deviation of 1.7147%. The maximum excess enthalpy for ternary system was 627.16 J·mol^-1.