Stability of carrollite (2024)

This vignette was compiled on 2024-12-02 with JMDplots 1.2.20-13 and CHNOSZ 2.1.0-27.

Check thermodynamic parameters for carrollite

This compares the thermodynamic parameters for carrollite in the OBIGT database with values calculated on-the-fly. The latter values include computed parameters for the high-temperature polymorph and heat capacity coefficients for both polymorphs. After the test, we reset the OBIGT database so the testing data don’t get in the way of the following calculations.

# Calculate parameters
calc <- calc_carrollite()
# Get parameters stored in OBIGT
ref <- info(info("carrollite", c("cr", "cr2")))
# Columns of OBIGT with parameters to check
ichk <- 10:22
stopifnot(all.equal(calc$cr[, ichk], ref[1, ichk], check.attributes = FALSE, tolerance = 1e-4))
stopifnot(all.equal(calc$cr2[, ichk], ref[2, ichk], check.attributes = FALSE, tolerance = 1e-4))
reset()

Add thermodynamic parameters for aqueous Co complexes

This uses CHNOSZ::logB.to.OBIGT() to fit formation constants for aqueous Co complexes (Migdisov et al., 2011) to an equation with two adjustable parameters (ΔG°_f and S°) that are then added to OBIGT.

complexes <- add_Co_aqueous()
## mod.OBIGT: updated CoCl+(aq)
## logB.to.OBIGT: mean difference between logB (experimental) and logK (calculated) is 0.0134
## mod.OBIGT: updated CoCl2(aq)
## logB.to.OBIGT: mean difference between logB (experimental) and logK (calculated) is 0.0172
## mod.OBIGT: updated CoCl3-(aq)
## logB.to.OBIGT: mean difference between logB (experimental) and logK (calculated) is 0.0987
## mod.OBIGT: updated CoCl4-2(aq)
## logB.to.OBIGT: mean difference between logB (experimental) and logK (calculated) is 0.0404
## mod.OBIGT: updated CoHS+(aq)
## logB.to.OBIGT: mean difference between logB (experimental) and logK (calculated) is 0.079

The fitted parameters are listed below for comparison with Table 1 in the paper.

Co <- info(info(c("CoCl+", "CoCl2", "CoCl3-", "CoCl4-2")))
Co$G <- round(Co$G)
Co$H <- round(Co$H)
Co$S <- round(Co$S, 3)
rownames(Co) <- Co$name
kable(Co[, c("G", "H", "S")])

	G	H	S
CoCl+	-190674	-228519	-50.692
CoCl2	-318845	-375729	62.333
CoCl3-	-459477	-559857	93.327
CoCl4-2	-601033	-742682	131.788

logf_O₂-pH diagram with carrollite (Figure 5)

carrollite_5(res)

Comparison of Cu-Co and Fe-Cu diagrams (Figure 8)

carrollite_8(res)

Experimental and fitted C_p for carrollite (Figure S3)

carrollite_S3()

Experimental and fitted formation constants for Cl^- complexes (Figure S4)

carrollite_S4(complexes)

log K of reactions showing temperatures of linnaeite in and carrollite out (Figure S5)

carrollite_S5()

Compare mosaic stack (with carrollite) to `CHNOSZ::solubility()` calculation for Co or Cu without carrollite (Figure S6)

carrollite_S6(res)

JMDplots vignettes

Stability of carrollite (2024)

Check thermodynamic parameters for carrollite

Add thermodynamic parameters for aqueous Co complexes

logf_O₂-pH diagram with carrollite (Figure 5)

Comparison of Cu-Co and Fe-Cu diagrams (Figure 8)

Experimental and fitted C_p for carrollite (Figure S3)

Experimental and fitted formation constants for Cl^- complexes (Figure S4)

log K of reactions showing temperatures of linnaeite in and carrollite out (Figure S5)

Compare mosaic stack (with carrollite) to `CHNOSZ::solubility()` calculation for Co or Cu without carrollite (Figure S6)

References

JMDplots vignettes

Stability of carrollite (2024)

Check thermodynamic parameters for carrollite

Add thermodynamic parameters for aqueous Co complexes

logfO2-pH diagram with carrollite (Figure 5)

Comparison of Cu-Co and Fe-Cu diagrams (Figure 8)

Experimental and fitted Cp for carrollite (Figure S3)

Experimental and fitted formation constants for Cl- complexes (Figure S4)

log K of reactions showing temperatures of linnaeite in and carrollite out (Figure S5)

Compare mosaic stack (with carrollite) to CHNOSZ::solubility() calculation for Co or Cu without carrollite (Figure S6)

References

logf_O₂-pH diagram with carrollite (Figure 5)

Experimental and fitted C_p for carrollite (Figure S3)

Experimental and fitted formation constants for Cl^- complexes (Figure S4)

Compare mosaic stack (with carrollite) to `CHNOSZ::solubility()` calculation for Co or Cu without carrollite (Figure S6)