Liquid-liquid equilibrium (LLE) data correlation of multicomponent mixtures is frequently carried out without using any procedure to ensure that the model parameters obtained for the totally miscible binary mixtures are consistent with such behavior (i.e. they do not lead to two liquid phases in equilibrium). In other words, the behavior of the model beyond the LLE region fitted (experimental tie-lines) is not usually considered in LLE correlations. It seems to be wrongly assumed that the mere absence of tie-lines data in totally miscible regions should guarantee that the parameters resulting from the LLE correlation lead to total miscibility in such homogeneous regions. We have checked that for the correlation of certain type 1 ternary systems (Treybal classification) a high probability exists of obtaining inconsistent model parameters, which lead to type 2 instead type 1 ternary behavior, unless specific restrictions for such parameters are imposed during the correlation. Commercial tools to carry out this type of data fitting, which are frequently included in process simulation packages such as Aspen Plus, do not include the possibility of applying such restrictions and consequently they could provide this type of misleading correlation results with serious consequences in equipment design. In the present paper, LLE data correlation for certain type 1 ternary systems has been carried out using Aspen Plus resulting in inconsistent type 2 results. These same systems have been satisfactorily correlated using our own correlation tools including restrictions to ensure the required miscibility behavior, and thus obtaining consistent parameters. A similar problem could occur in the correlation of the less frequent island (or zero) type ternary systems. Some examples are also presented for such type of systems.

多组分混合物的液-液平衡（LLE）数据相关性经常在没有使用任何程序的情况下进行，以确保为完全可混溶的二元混合物获得的模型参数与这种行为一致（即，它们不会导致两个液相处于平衡状态） ）。换句话说，在LLE相关中通常不考虑超出拟合的LLE区域（实验联系线）的模型的行为。似乎错误地认为，在完全可混溶的区域中仅缺少联络线数据应该保证由LLE相关性得出的参数会导致在此类均质区域中的完全可混溶性。我们已经检查过，对于某些类型1三元系统（Treybal分类）的相关性，存在获得不一致的模型参数的可能性很高，导致类型2而不是类型1的三元行为，除非在相关过程中对此类参数施加了特定限制。进行此类数据拟合的商业工具（通常包括在过程模拟软件包中，例如Aspen Plus）不包含应用此类限制的可能性，因此，它们可能会提供此类误导性的相关结果，给设备设计带来严重后果。在本文中，已经使用Aspen Plus对某些类型1三元系统进行了LLE数据关联，从而导致不一致的类型2结果。这些相同的系统已使用我们自己的相关工具令人满意地进行了相关，包括确保所需的混溶行为的限制，从而获得了一致的参数。在不太频繁的岛（或零）类型三元系统的相关性中可能会发生类似的问题。还提供了此类系统的一些示例。