Geochemist's Workbench Support Forum

# All Activity

1. Today
2. ## The software requests reinstallation

Hi good day. Please I need your help again, when trying to use some modules of the GWB for students it indicates to me that I must reinstall the software, annex document with the screen print of the error. Thanks in advance. error de gwb.docx
3. Yesterday
4. ## Calculation of (maximum) mineral / metal solubility in a reaction path using REACT

Hi Sebastian, There’s an example diagram in the React section of GWB.com/diagrams.php entitled Mineral solubility. You can click on the React icon to download the script. It sets a fluid in equilibrium with Kaolinite at pH 3, then scans all the way to pH 9. We’ve shown a plot of the species distribution in the fluid as a function of pH, but you could easily plot the Al+++ Component in the fluid (the sum of the dissolved Al+++ species) to see the total dissolved aluminum. It’ll look like a curve traced just above the highest concentration species at each pH. In this example, the mineral is least soluble at ~pH 5.4, and the solubility increases in either direction from there. You could easily make a similar diagram with a sliding temperature path to figure the effect of temperature on the solubility of an iron mineral. Of course, there are many factors that can control the solubility of minerals, such as pH, oxidation state, ionic strength, the presence of various complexing ligands in different concentrations, and temperature. React (or SpecE8) can calculate the solubility of a mineral in any fluid you specify, but not every fluid, at least in a single calculation. In other words, you can’t determine from a single reaction path the maximum solubility of a mineral considering every possible fluid composition. You can only find the maximum solubility subject to the prescribed conditions. React lets you consider one variable at a time, and Phase2 lets you consider two at a time. Hope this helps, Brian Farrell Aqueous Solutions
5. ## Calculation of (maximum) mineral / metal solubility in a reaction path using REACT

Hello GWB experts, I am wondering if there is an easy way to calculate the (maximum possible) solubility of a mineral / metal in a fluid along a reaction path in the REACT program. Assuming an reaction path of a cooling fluid (e.g. from 250 °C to 25 °C) with different dissolved metal species (e.g., Fe, Na, Ca ....). REACT show nicely the actual concentrations of the different aqueous species, as well the amount of minerals that precipiate once saturation is reached. Is it possible to calculate and show the max. solubility of metal / mineral in this context (e.g. max solubilty of Fe at temperature)? Many thanks in advance, Sebastian
6. Last week
7. ## My License is disabled

Hi Raquel, No worries. I'm glad to hear you're up and running now. Cheers, Brian
8. ## My License is disabled

Hello Brian, Sorry for the delay in my response, until today I had access to the internet. I followed the steps you indicated and the program is active again and on my desktop computer. Thanks for the support. Regards.
9. ## My License is disabled

That error message indicates a reboot is required. It's not likely that the software will work in safe mode, though, so I'll return your license from my end so you can activate on your desktop. As for your desktop, you need to return to the GWB Activation Utility, select the block of text "Source: License File ..." and hit Delete. Then click New... and paste in your activation code (GUA12...) and hit Activate. Regards, Brian
10. ## My License is disabled

Hello Brian, Thanks for the prompt response, I would like to use the software preferably on the desktop computer, since the laptop needs to be formatted, in fact it is currently working in safe mode, maybe this has to do with the error that the Software throws. I attached the screen print of the error that it throws in the laptop. On the other hand, once you see the error that you throw in the laptop, could you please tell me how to disable the software on the laptop? Regards.

12. ## Regarding UO2 (uraninite) mineral solubility chart at temperatures of 25, 32 and 80C and under constant pH or pe conditions using Tact

Hi Polly, Tact is for making stability diagrams, like those you’ve made in Act2, but with a temperature axis. In other words, Tact makes polythermal calculations while Act2 makes isothermal calculations. The diagrams you’ve shown from the report are isothermal calculations repeated at different temperatures. It looks like React was used to perform the solubility calculations you’ve shown in the report. You can use sliding and fixed activity paths to scan over a range of pe values, while holding pH constant, or to scan over pH values while holding pe constant. As you run these calculations, you should be aware of the stability range of water. If you start or end a calculation far outside the stability range, you may encounter concentrations that don’t seem to make much sense at first glance. It might be helpful to create rough calculations in Act2 to determine the pH or pe ranges where water is stable, and also where the minerals of interest are stable. There’s no point in setting up the React calculation far outside the mineral stability range, especially if you’re leaving the stability range of water. You can plot data from multiple React calculations together in a single plot by exporting the numerical values to Excel. You can also use the exported information to fill your table. For more information, please see 3.5 Buffered paths and 3.6 Sliding activity and fugacity in the GWB Reaction Modeling Guide. Please see as well 6.7 Exporting the plot in the same guide. Again, please post on the front page of the GWB forum, not in the archive of old posts. Regards, Brian
13. ## Temperature of Minteq database

Hi Gustavo, A thermo dataset is a compilation of reactions with log K values at specific temperatures. You cannot simply change the temperature range without replacing the log K values. I'd recommend starting with one of the datasets that goes up to 300 C and adding the specific REE elements, species, and minerals that you need. The TEdit app will be useful for this. In the future, please post on the front page of the main GWB forum, not in the archive of old posts. Regards, Brian Farrell Aqueous Solutions
14. ## GWB for Mac

I will give that software a try. thank you for the advice!
15. ## GWB for Mac

Hi Jonah, The GWB runs under Windows 10, Windows 8 & 8.1, and Windows 7. You can also run the software on a Mac using virtualization software such as Parallels Desktop or using a dual boot configuration with a program like Boot Camp. Regards, Brian Farrell Aqueous Solutions LLC
16. ## GWB for Mac

hi there. my name is Jonah Jordan and I was recently approved to download the software but it seems to only work on windows. is there a MacOs version I could download for my MacBook? Thank you
17. ## My License is disabled

Hi Raquel, We'll get this straightened out. Would you prefer to keep using the software on your laptop, or on the new desktop? The software doesn't appear to be deactivated from the laptop, so you'll need to actually deactivate it if you want to use it on the desktop. Can you please send a screenshot of the GWB Activation Utility and the GWB dashboard from the laptop, along with any error messages that you receive? Thanks, Brian Farrell Aqueous Solutions
18. Earlier
19. ## My License is disabled

Hello, I need your help. My license was installed on a laptop, I used it until December 2018, I got it on September 19 of that same year, but these months I had not needed to use it, and now that I started my master's thesis I need the software again, however, the program indicated to me that the license was deactivated. I tried to activate it on the same laptop where it was installed and it indicated an activation error. For this reason I decided to copy it to a desktop PC, but when I entered the license file it indicated the following: Error: Network connect to this_host failed. The license file indicates this_host, and the server is not running on this host. If it's running on a different host, This_host should be changed to the correct host. FlexNet Licensing error: -95,378. Please help me, I am worried, I need the program to start processing the data of my thesis. error GWB.docx
20. ## Temperature of Minteq database

Dear, Is it possible to increase the temperature range of the database ?. Currently it reaches up to 100 ° C, but I need to perform analyzes in a range of 300 ° C. I do not use a different database because the analyzes are related to the REE. Yours sincerely, Gustavo.
21. ## Regarding UO2 (uraninite) mineral solubility chart at temperatures of 25, 32 and 80C and under constant pH or pe conditions using Tact

Dear Brian, I would like to plot the uraninite (UO2) solubility chart with the function of pH or pe at temperatures of 25, 32 and 80°C, just like the examples in Figs. 1 and 2 captured in the technical report. When the plots have been done, the raw data should be summarized in the Table 1. Please refer to the attachment. Should I use the Tact module to perform them? Please also refer to the script of Tact. Thanks for your kind instruction. Best regards, Polly Regarding mineral solubility calculation_to Brian 20190609.docx Solubility of uraninite.tac
22. ## Difference between an open and closed system?

I do not quite understand the differences between an open and closed system. In my view for a closed system, the amounts of reactants and fluids are given at first, then the reaction goes ahead, resulting in the decomposition of reactants and the formation of products. None of the reactants and fluids is fixed. As a contrast, one or some components of the reactants and fluids is fixed during the reaction. I am not sure whether my understanding is correct or not, so any suggestions are welcomed.
23. ## Regarding gas fugacity at high temperature (80C) in Act2

Hi, Brian, Thanks so much for your instruction. The pH/Eh diagram at 80C has been successfully plotted after selecting the "alter logk" of config. I wondered GWB would automatically calculate the species. All the best, Polly
24. ## Regarding gas fugacity at high temperature (80C) in Act2

Hi Polly, Like I said, you need to use the “extrapolate” option to match your 80 C plot to the technical report. When set to 80 C, Act2 by default doesn’t load the UO2(OH)3- and UO2(OH)4-- species that you see in the report because they have log Ks only at 25 C. If you extrapolate these log K values to higher temperatures, Act2 will load them, and you’ll get the same diagram. Regards, Brian
25. ## Regarding gas fugacity at high temperature (80C) in Act2

Dear Brian, Thanks for your response. Yes, my plot without consideration of gas fugacity is not the same as that of the above technical report. Please refer to the attached plot and raw data. As to the termo dataset, ver.8.0 of GWB was used in the technical report, while mine is ver.12.0. Is it possible for different version of thermo dataset? In addition, you can find the it's also not the same plot for 25C and 80C in the technical report. Please refer to the two figures of Technical report_25C and 80. So, I think they should consider the logk value in their 80C. So far, I still don't know how to do in the next step. Polly Plot without fugacity.docx U_80C in pure water_pH vs pe_wo fugacity.ac2
26. ## Regarding gas fugacity at high temperature (80C) in Act2

Hi Polly, The CO2 fugacity you specify should be unique for your particular calculation. Looking at the figure you’ve provided from the report, no species with carbon predominate, so I’m reasonably certain that’s not the missing link (in this type of calculation, at least). Act2’s Results pane (as well as the “Act2_output.txt” file that you can access by clicking “View Results” from the Plot pane) includes a list of all the species and minerals included in the calculation. If you look there, you’ll notice that UO2(OH)3- and UO2(OH)4--, which predominate in the upper right of the technical report’s diagram, but not yours, are missing. If you look in the thermo dataset, you’ll see they only have log K values specified at 25 C, so they won’t be considered in your 80 C calculation. Act2’s “extrapolate” function can be used to estimate log K values outside their known values. This can be quite dangerous, especially when only a single log K value is known, but I believe that’s what has been done in the report. For more information, please see the Thermo Datasets chapter in the GWB Reference Manual, as well as the extrapolate command in the GWB Command Reference. Regards, Brian Farrell Aqueous Solutions
27. ## Regarding gas fugacity at high temperature (80C) in Act2

Dear Brian, I am not sure what the value of gas fugacity (like CO2) at high temperature (80C) in pure water (no presence of complexing ions) should be input for uranium (UO2) pH/Eh diagram? I tried to input fugacity of CO2 <-> HCO3- using arbitary data, like 1, 0.8...0.3 and the plot was not the same as that of technical report. Please refer to the attached Act2 raw data and the technical report. Thanks again for your kind help. Polly U_80C in pure water_pH vs pe.ac2
28. ## How to remove the dashed line in the mosaic diagram of Act2

Dear Brian, Sorry! I have already know how to deal with the mosaic bounds. Polly
29. ## How to remove the dashed line in the mosaic diagram of Act2

Dear Brian, I tried the mosaic diagram and the result is the same as that of technical report based on your suggestion. However, how to remove the dashed line in the attached diagram? Thanks for your kind assistance in advance. Polly U 25 C in K area.emf
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