Modification of Pitzer Ion interaction Parameters

[RenAmb]

Hello everyone,

I am currently working on alkaline leaching of silica rich residues. I added a set of equilibrium for silicate species. However, I would like to add for those new silicate species their corresponding Pitzer Ion-Interaction parameters : beta0 and beta1. How it can be done and could I be able to change those parameters for existing species in the database ?

Thanks for you help !

[dlparkhurst]

Yes, you can add and (or) replace Pitzer parameters. I would not change pitzer.dat, rather I would either include the modifications in your input file, or create another file that is inserted into your input file with INCLUDE$.

The following replaces beta0 and beta1 for Na+ Cl- interaction. The order of the ions should not matter. If the parameter exists in phreeqc.dat (which they do), then the parameter is replaced with the new values (in this case the same values as pitzer.dat). If the parameter does not exist, then it is added. See the documentation of the PITZER data block in the user's manual for more information.

Code: [Select]

PITZER
-B0
  Cl-       Na+       7.534e-2   9598.4        35.48     -5.8731e-2    1.798e-5   -5e5  # ref. 3
-B1
  Cl-       Na+       0.2769        1.377e4    46.8        -6.9512e-2   2e-5      -7.4823e5  # ref. 3
SOLUTION
-units mol/kgw
Na 1
Cl 1
END