MinKin: A kinetic modeling program for the precipitation, dissolution, and phase transformation of minerals in aqueous solution

• We describe a novel mathematical technique for fitting kinetic models to experimental data in aqueous geochemical systems.
• MinKin uses differential evolution to optimize the rate constants of a kinetic model to aqueous and mineral species data.
• MinKin calculates rate constants from experimental data in systems with 2 aqueous and 3 mineral components.
• Accuracy of refined rate constants is limited only by the error in experimental data.

The development of time-resolved, synchrotron scattering techniques has recently enabled the collection of in situ mineral abundance data during mineral–fluid reactions. However, few computational algorithms exist to analyze the kinetics of such reactions. Here we present MinKin (for “Mineral Kinetics”), a global optimization code for Matlab capable of fitting a standard chemical kinetic model to experimental mineral abundance data. MinKin allows users to specify the species and reactions of a geochemical system consisting of a fluid with up to two aqueous species and up to three mineral species, and then uses the global optimization algorithm of Differential Evolution (DE) to calculate the rate constants that minimize the error between the model and the data. Trial calculations reveal that MinKin is able to simultaneously calculate up to six rate constants on a time scale of minutes, with an accuracy of roughly the same magnitude as that of the input data.