ESTIMATION OF THE NITTA-CHAO PARAMETER FOR THE ETHER-GROUP - ETHER PLUS N-ALKANE MIXTURES

In this work we have estimated the structural and interactional parame ters of the ether-group for the group contribution model of Nitta-Chao using a extensive experimental database of thermodynamic properties o f ethers (monoethers, polyethers and acetals) and ether+n-alkane and e ther+ether mixtures. The results obtained by Nitta-Chao model with thi s parameters get closer to the experimental values than those obtained with parameters of Eckart et al. (1986). The thermodynamic properties obtained by the Nitta-Chao model with old and new parameters were com pared to predictions by other models such as Flory (1965) theory, DISQ UAC (Kebiaian, 1977) model and UNIFAC model (versions of Dang and Tass ios, 1986, and Larsen et al., 1987).