Volume-translated Peng-Robinson (VTPR)
The group contribution equation of state model VTPR has been added as fourth supported model in the UNIFAC Consortium in 2017. It is the successor of PSRK in many regards but will not replace PSRK. The developers of VTPR have tackled quite some weaknesses of PSRK and the UNIFAC Consortium is now busily building up the parameter base and the group assignments. The combination of an improved model and the creation of new interaction parameters plus an optimized group assignment scheme based on the current Dortmund Data Bank promises very precise, widely applicable, and reliable predictions.
All the changes (new and revised parameter) for VTPR are shown in the following diagrams:
The UNIFAC Consortium added interaction parameters for 171 main group pairs; interaction parameters have been published for 276 main group pairs, now parameters for 447 main group pairs are available. Additionally, interaction parameters for three main group pairs have been revised.
See also a list of VTPR-related publications.