> I am trying to use PHREEQC to simulate the formation of green rust (iron corrosion product). Its formula is considered to be Fe4Fe2(OH)12SO4------the first Fe is in 2nd valence and the second Fe is in 3rd valence (So I might write it as Fe(II)4Fe(III)2(OH)12SO4. But the PHASE data block in PHREEQC seems only to accept single valent element on left hand side. I thought of SOLID-SOLUTION but the green rust is not yed considered as any aggregate of other phases. I don't know if there is any other way to handle this problem. > the reaction equation is: > Fe4Fe2(OH)12SO4 = 5Fe(OH)2 + Fe2+2 + SO4-2 + 1/2O2 + H2O This equation should be adequate for the PHASE definition. I just did a little balancing for PHREEQC: Fe4Fe2(OH)12SO4 = 5Fe(OH)2 + Fe+2 + SO4-2 + 0.5O2 + H2O If this stoichiometry is added to solution, the iron will be distributed between +3 and +2 states depending on electron acceptors. With no additional electron acceptors in the system the ratio of Fe(2):Fe(3) should be 2:1. David David Parkhurst (dlpark@xxxxxxxx) U.S. Geological Survey Box 25046, MS 413 Denver Federal Center Denver, CO 80225 Project web page: https://wwwbrr.cr.usgs.gov/projects/GWC_coupled
Please note that some U.S. Geological Survey (USGS) information accessed through this page may be preliminary in nature and presented prior to final review and approval by the Director of the USGS. This information is provided with the understanding that it is not guaranteed to be correct or complete and conclusions drawn from such information are the sole responsibility of the user.
Any use of trade, product, or firm names in this publication is for descriptive purposes only and does not imply endorsement by the U.S. Government.
The URL of this page is:
https://wwwbrr.cr.usgs.gov/projects/GWC_coupled/phreeqc/mail/msg00158.html
Email:dlpark@usgs.gov
Last modified: $Date: 2005-09-13 21:04:21 -0600 (Tue, 13 Sep 2005) $
Visitor number 3331 since Jan 22, 1998.