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NIST Standard Reference Database 4

NIST Thermophysical Properties of Hydrocarbon Mixtures Database: Version 3.2

NOTE: Many of the fluids contained in NIST4 are also available in the REFPROP database. The REFPROP database is recommended over NIST4 when REFPROP contains the fluids of interest.

Effective immediately, there will be a minimum $30.00 shipping charge for all international shipments of databases via UPS International. Customer will be responsible for their own duties, tax, and VAT. Contact (844) 374-0183 (Toll Free) or data [at] (data[at]nist[dot]gov) if you have questions.

Price: $200.00   PLACE ORDER

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SUPERTRAPP is an interactive computer program for predicting thermodynamic and transport properties of pure fluids and fluid mixtures containing up to 20 components. The components are selected from a database of 210 components, mostly hydrocarbons. Version 3.2 is a minor upgrade from Version 3.1 that incorporates some bug fixes, and increases the number of fluids from 201 to 210.

SUPERTRAPP performs phase equilibria calculations and gives the thermophysical properties of all phases and the feed. These results include:

Equilibrium properties:

  • density
  • compressibility factor
  • enthalpy
  • entropy
  • Cp
  • Cp/Cv
  • sound speed
  • Joule-Thomson coefficient

Transport properties:

  • viscosity
  • thermal conductivity


  • bubble and dew point pressure calculations
  • bubble and dew point temperature calculations
  • flash calculations ({T,P}, {T,S} and {P,H})
  • saturation properties for pure components
  • tables of thermophysical properties with user selected dependent and independent variables
  • ability to add new fluids using minimal data (user must supply at least Tc, Pc, Vc, MW and boiling point)
  • ability to estimate properties of petroleum fractions characterized by an average normal boiling point and an API gravity
  • choice of units
  • FORTRAN source code for property calculations

Please click here to view the PDF version of Users' Guide

System Requirements: SUPERTRAPP is designed to run on a personal computer with an MS-DOS or PC-DOS operating system, version 3.31 or higher. It also runs in a DOS window under MS Windows 95, 98, 2000, NT, XP and ME. Windows NT required for older processors. The package requires 430 kilobytes of available RAM and a hard disk drive with 1.5 megabytes of available space. Math coprocessor required. Supertrapp now works on 32-bit and 64-bit MS Windows.

For more information please contact:

Standard Reference Data Program
National Institute of Standards and Technology Mail Stop 6410
Gaithersburg, MD 20899-6410
(844) 374-0183 (Toll Free) 

The scientific contact for the database is:

Marcia Huber
Fluid Mixtures Data Center
National Institute of Standards and Technology Boulder, CO 80303
(303) 497-5252 marcia.huber [at] (marcia[dot]huber[at]nist[dot]gov)

Keywords: Chemical engineering; chemical manufacturing; chemical property; chemistry; dielectric constants; equation of state; fluids; heat capacity; hydrocarbons; LNG; mixtures; natural gas; petrochemical; phase equilibria; thermal conductivity; thermodynamics; thermophysics; transport property; viscosity.

Customer Support 

Created August 27, 2010, Updated November 3, 2021