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I want to add Rhenium(Re) species like ReO4-1 into GWB library to study its reduction mechanism with Fe+2. What species of Rhenium and Iron are required along with their data types to study rhenium reduction with Iron? Please elobrate step by step, how can i add these species into the library of GWB?

 

 

If I wan to make ReO4-1 as base specie in SpecE8, how to proceed it, if its thermodata is not present in the GWB library?

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Hi,

 

GWB's default thermo dataset, thermo.tdat, does not contain any Re species, but the datasets used by the software are fully editable, so you're only limited by the availability of data in the literature. Another dataset installed with the software, thermo.com.v8.R6+.tdat, does contain the basis species ReO4-. If you're interested in Re, you should look in the literature for equilibrium constants for reactions involving Re species, or information on the standard state free energy of formation of various Re species so that you can calculate equilibrium constants. You might find reactions for protonated or deptotonated forms of ReO4-, complexes with common ligands, or most important for you, species in different oxidation states. You'll probably want to include as well some Re-bearing minerals.

 

I recommend using TEdit, the graphical thermo data editor in GWB10, to create your thermo dataset. To get started, use thermo.com.v8.R6+.tdat, which contains the element Re and the basis species ReO4-. Or, you can copy and paste/ drag and drop (see section 9.2.6 in the GWB Essentials Guide) the element and basis species into a different dataset, like thermo.tdat. Either way, you should rename the dataset so that you don't overwrite the original information. Next, choose a Re species of a different oxidation state to be a redox species in the dataset. You'll need to know the equilibrium constant for a redox reaction involving that species, the basis species, and O2(aq), H2O, H+, etc. Sections 9.2.3 and 9.2.4 in the GWB Essentials Guide describe how to add reactions to your thermo dataset. After the redox species is added, you can add various protonated or deprotonated forms or complexes of that oxidation state to the Aqueous species section of the thermo dataset. Be sure to write the reaction in terms of that species. Any minerals in that oxidation state should be added to the minerals section.

 

This is a little difficult to describe without having an example of a species that you'd like to add. If you can provide more information, I'd be happy to help.

 

Regards,

 

Brian Farrell

Aqueous Solutions

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(Thanks for your cooperation and sincere guidance)

Can you explain how to excess TEdit, the graphical thermo data editor in GWB for creating my own thermodata directory? (I could not found it)

However I have found ReO4- in thermo.com.v8.R6+.tdat. I also also have to add ReO2, ReO3, Re2O3, Re species in thermo data for so that I may study the reduction of ReO4-1.

Can you explain how to edit all of these species step by step as base species, solution, mineral, gas and reduction couple as well.

thanks

Mumtaz Khan

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Hi Mumtaz,

 

You can access TEdit from the Support tab of the GWB dashboard. Just click the button labeled "Edit thermo data". Then, click File -> Open - > Thermo Data... and browse to select an existing dataset. Alternatively, you can open TEdit from any GWB program by selecting File -> View -> thermoDatasetName.tdat. Doing this will open the currently loaded thermo dataset in TEdit.

 

You can find some quick tutorials on TEdit here, and more detailed information is available in chapter 9 of the GWB Essentials Guide.

 

Are ReO2, ReO3, Re2O3, and Re aqueous species or are they minerals (or both)? Assuming they're in the aqueous phase, you'll need to write a balanced reaction to form each species. If there is an ReO2(aq) species, for example, then you should be able to write a redox reaction with ReO4- involving O2 or the e-. If you have an equilibrium constant for this reaction, then you can add the reaction and log K to a thermo dataset. Take a look at how other redox species appear in the thermo datasets to use as a guide.

 

Regards,

Brian

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Dear Brian

I have to found ion size for editing these ReO2, ReO3, EDTA, H2O2 and few other species. Can you guide how to calculate the ion size in GWB thermodata?

thanks

Mumtaz Khan

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