Vapor-liquid equilibrium for methanol + polyoxymethylene dimethyl ethers binary system under normal atmospheric pressure

At 101.3 kPa constant pressure, the VLE data of methanol-DMM3 (polyoxymethylene dimethyl ethers with degree of polymerization of n, i.e., DMMn) system were determined by using an improved Rose still. Thermodynamic consistency of the obtained vapor liquid equilibrium data were examined. The results were satisfied with Gibbs-Duhenm's thermodynamic consistency. The VLE data were correlated by Wilson, NRTL and UNIQUAC activity coefficient model by Aspen Plus v7.1. The objective function was optimized by the maximum likelihood method and the corresponding model parameters were returned. Compared with the experimental results, the average absolute deviations for temperature and the composition in the vapor phase were less than 0.65 K and 0.0065, respectively. This work provides the important engineering data for an engineering design and further study in the multicomponent system containing methanol and DMM3.