Extension of the validation method for vapor–liquid equilibrium data to systems with nonvolatile components

In this work, a method is proposed to validate the experimental data of solutions of n-components in vapor–liquid equilibria (VLE) with some nonvolatile component (nv-VLE). The methodology is based on the resolution of the differential Gibbs–Duhem equation using two forms (differential and integral) described in a previous work. The combination of both forms evaluates as many relationships between the variables that define each data series in equilibrium (p, T, x_{1, …, n-1}, y_{1, …, n-1}) as degrees of freedom the problem has, although in this work it is only necessary to use the integral form. The proposed method is applied to 70 experimental data series published in the literature, considering the numerical limits previously assigned to parameters established for the integral-form, according to the following. (a) A parameter ψ is identified as p or T according to if the data are iso-T or iso-p; (b) verification of the data is assessed by the difference (Formula presented.), with (Formula presented.) > 0, and (Formula presented.) is determined by an uncertainty procedure of the inconsistency function (Formula presented.), being (Formula presented.); and (c) The parameter κ_ψ depends on the type of equilibrium. With κ_ψ = 5, the rejection ratio of the total analyzed is 12%, this percentage increases as the level of quality required increases above 31% for κ_ψ = 3. The calculations require a precise representation of the binomial {data+model}, which produces excellent results for the treatment of nv-VLE and the properties of solutions, whose parametrization is achieved by an advanced procedure of combined optimization.