Welcome to the AIOMFAC website

This website is designed to provide access to the thermodynamic model AIOMFAC in the form of an interactive web application and to provide supporting information.

News and latest changes ↑Top

This section lists important events and changes related to AIOMFAC-web in reverse chronological order.

  • January 23, 2019: A minor model update to version 2.21. A bug concerning input composition verification and a related error check have been fixed (no changes to actual AIOMFAC calculations).

  • August 13, 2018: Several changes were made to hardware, software and content of the AIOMFAC website.  (1) The website is now hosted permanently on a new server at McGill University, accessible via the following URL: https://aiomfac.lab.mcgill.ca. The previous, temporary server at McGill will redirect to this address. The Caltech-hosted website remains available.  (2) The contents of this page as well as the Hints & Examples page, previously listed as "Help" page, were updated.  (3) A new option on the "Run model" input form makes it possible to display the model results page in a new browser tab. This allows keeping the input form open for easier adjustments.  (4) AIOMFAC-web has been updated to version 2.20, which includes minor revisions and optimization of the code.  (5) For the adventurous: the Fortran source code of the AIOMFAC-web version 2.20 (and future updates) and supporting information is made availabe publicly via https://github.com/andizuend/AIOMFAC.

  • November 22, 2017: Recent hardware issues and related repairs of the server at Caltech have caused temporary unavailability of this website. To avoid longer unavailabilities in future, the AIOMFAC model website is now also hosted on a server at McGill University, currently accessible via the following URL: http://web.meteo.mcgill.ca/aiomfac/. The Caltech-hosted website (http://www.aiomfac.caltech.edu) remains available.

  • May 15, 2015: A search tool has been added to the navigation menu to aid you in finding relevant information on this website.

  • April 24, 2014: Initial input data validation, error, and warning checks have been further improved (including the blocking of automated spam upload). The model version was changed to 2.18. However, these changes do not affect the actual AIOMFAC code nor model output.

  • June 19, 2013: The AIOMFAC model has been corrected for a typo in the supplementary tables of Hansen et al. (1991) for the relative surface area parameter of the ketone subgroup CH3CO. The previously used value (1.448 instead of 1.488) led to slight deviations of activity coefficients in affected systems, e.g., noticeable at conditions of very high dilution in the system of water + acetone. We thank Steven Compernolle for the hint. The AIOMFAC-web version has been changed to 2.16.

  • December 10, 2012: Additional error and warning checks have been implemented in the AIOMFAC-web model to prevent certain types of incorrect input data. The model version was changed to 2.15.

  • October 16, 2012: The webpages have been updated to be compliant with HTML5 syntax and features. The AIOMFAC-web model has been updated to version 2.14 (including output of results in HTML5 syntax and internal performance upgrades).

  • August 17, 2012: The model input page has been updated to fix compatibility issues with older web browsers (and their interpretation of JavaScript code).

  • June 06, 2012: AIOMFAC-web version bug-fix update to 2.11. A bug in the model code slightly affecting activity coefficients in mixtures containing organic compounds and non-1:1-electrolytes has been corrected. Thanks to Steven Compernolle for pointing out this error.

  • May 11, 2012: AIOMFAC-web version update to 2.10. New functional groups are made available in AIOMFAC-web: hydroperoxide, peroxyacid, peroxide, peroxyacyl nitrate (PAN), and organonitrate. The new functional groups and the parameterization of their interactions with other functional groups and inorganic ions are described in Zuend and Seinfeld (2012). The list of available functional groups and the interaction matrix shown on the page About AIOMFAC have been updated accordingly.

  • April 01, 2012: AIOMFAC-web version update to 2.02. The version update includes a minor correction in TeX format of model output in text files, allows now 101 data points per model run, and addresses numerical issues at extremely high electrolyte concentrations.

  • February 17, 2012: Additional examples of AIOMFAC-web calculations have been added to the Hints & Examples page. It is demonstrated how the water content and mixture composition at a given RH can be computed and how the solubility and deliquescence RH of a component in a multicomponent solution can be determined with AIOMFAC.

  • January 10, 2012: The AIOMFAC website has been launched with AIOMFAC-web version 2.0 available for online calculations.

    AIOMFAC-web 2.0 covers water, inorganic ions and the following organic functional groups: hydroxyl, carboxyl, ketone, aldehyde, ether, ester, alkenyl, aromatic hydrocarbon, aromatic carbon-alcohol, and different alkyl groups. The inorganic ions available are: H+, Li+, Na+, K+, NH4+, Mg2+, Ca2+, Cl-, Br-, NO3-, HSO4-, and SO42- (see further here).

Learn about the AIOMFAC model ↑Top

Use the navigation bar on top or the following link to learn more about AIOMFAC, its concept, development, and range of applications.

How to use AIOMFAC-web ↑Top

The model version made available online, termed AIOMFAC-web, allows the calculation of activity coefficients in organic-inorganic mixtures – from simple binary solutions to complex multicomponent systems.

The Hints & Examples page offers a step-by-step guide on how to use AIOMFAC-web, as well as useful information referring to the mode of calculation. Different examples of AIOMFAC-web calculations and related output analysis are described. In addition, you will find helpful information regarding model error and warning messages, browser compatibility, and technical problems.

Run the model ↑Top

Go directly to the model input form, enter the data for your system of interest and run the model.

Citation and references ↑Top

If you use results from AIOMFAC-web calculations for scientific publications or other forms of reports, please cite this website and the scientific articles describing the model as detailed here.

Check the list of references given at the end of About AIOMFAC and the information in the text on that page to find a number of sources describing the AIOMFAC model and its various applications reported in the scientific literature.

Acknowledgments ↑Top

Starting as the PhD thesis project of Andreas Zuend at ETH Zurich back in 2004, the AIOMFAC model has been under development for several years by now, involving a number of project partners. This website is one of the more recent products of that development process, with the goal of making the model available to the wider community. We are grateful for the financial support received from the following funding agencies, enabling the research and development of the AIOMFAC model and this website:

  – AIOMFAC model

  • Swiss National Science Foundation (SNSF), Project No. 200020-103651.
  • Swiss National Science Foundation (SNSF), Project No. PA00P2_126227.
  • Competence Center Environment and Sustainability of the ETH Domain (CCES), project IMBALANCE.
  • Office of Science (SC, BER), US Department of Energy, Grant DE-FG02-05ER63983.
  • US Environmental Protection Agency (EPA), STAR Research Assistance Agreement RD-833749.
  • Electric Power Research Institute (EPRI).
  • ETH Zurich, Switzerland (ETHZ), Research Grant ETH-0210-1.
  • US National Science Foundation (NSF), Grant AGS-1057183.
  • McGill University (Start-up Grant, A. Zuend)
  • Natural Sciences and Engineering Research Council of Canada (NSERC), Grant RGPIN/04315-2014).

  – Website & Server Hardware

Future development and improvement of the AIOMFAC model and this website, as well as the maintenance of the technical infrastructure and services, will depend on funds available. If you would like to support our future projects financially or as a project partner, please contact us.

© 2012 – 2018 Andreas Zuend, California Institute of Technology | McGill University last page update: 2019-01-23