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When considering the formation of uranophane, pH of the solution that the uranophane is in is one of the determining factors of how much of the uranophane is in mineral form or in the form of its ions. From a study performed by Tatiana Shvareva et al. in 2011, describes the dissolution of uranophane, in pH of 3 and pH of 4. The study demonstrates that in a more acidic environment, the concentrations of Ca, U and Si are more likely to be greater than in more basic environments where it is more likely they will form minerals. This is likely to happen when the acidic mine drainage is released into rivers or large water deposits and become diluted to a pH closer to that of water.

The Enthalpies of formation (from elements and from oxide species) and Gibbs free energies of formation (from elements) of the uranium minerals boltwoodite, Na-boltwoodite, and uranophane are shown in Table 1. Solubility constants (dissociation of minerals to ions) of the same minerals, determined using a bomb calorimeter in a study by Shvareva, Tatiana et al. in 2011, are shown in Table 2. The Gibbs free energies of formation show that the process, when the reactions from the individual elements to the oxides are taken into account, is Spontaneous. The enthalpies of formation, when only considering the reaction from the oxides to the mineral, suggest a relatively high probability for their Gibbs free energy of formation values to also be spontaneous.

Table 1. The enthalpy of formation (from oxide to mineral), enthalpy of formation (from individual elements to mineral), and Gibbs free energy (from individual elements to mineral) of boltwoodite, Na-boltwoodite, and uranophane. Table 2. Solubility constants and mass action equations for boltwoodite, Na-boltwoodite, and uranophane.