Jump to content
Geochemist's Workbench Support Forum

Error: Ionic Strength out of Range


Recommended Posts

I'm attempting to calculate speciation in a complex brine system and continually receive the ion strength out of range error. The error seems to be focused around the interactions of EDTA4- with Ca2+ and Mg2+. Oxalate also seems to have this same issue.

If I swap the EDTA concentration for the species we expect to dominate, CaEDTA2-, this just moves the error to another species in the calculation. The model seems to give accurate data when EDTA and Oxalate are removed from the calculations.

error.png

inputs.png

 

Link to comment
Share on other sites

Hello,

Taking a quick look at your basis input, it seems like your solution is extremely concentrated (> 200 moles of solute per kilogram of solution). Can you double check that the unit that you are using for your concentration measurements are correct? 

Best regards,
Jia Wang

Link to comment
Share on other sites

Hello,

Thanks for double checking the units. I did a quick test with the new units and swapped CaEDTA-- (more abundant species) for EDTA----, and the speciation calculation was successful. Did you alter any other parameters in file setup? Perhaps a unit was left unchanged for one of the basis species? If you would like someone to take a closer look, please attach the SpecE8 or React input file so we can troubleshoot. 

Hope this helps,
Jia

 

 

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...