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Title: Illite Dissolution Rates and Equation (100 to 280 dec C)

The objective of this suite of experiments was to develop a useful kinetic dissolution expression for illite applicable over an expanded range of solution pH and temperature conditions representative of subsurface conditions in natural and/or engineered geothermal reservoirs. Using our new data, the resulting rate equation is dependent on both pH and temperature and utilizes two specific dissolution mechanisms (a “neutral” and a “basic” mechanism). The form of this rate equation should be easily incorporated into most existing reactive transport codes for to predict rock-water interactions in EGS shear zones.
Publication Date:
Report Number(s):
DOE Contract Number:
Product Type:
Research Org(s):
DOE Geothermal Data Repository; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)
Lawrence Livermore National Laboratory
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Geothermal Technologies Office (EE-4G)
15 Geothermal Energy; geothermal; illite; dissolution kinetics; illite dissolution
OSTI Identifier:
  1. The Geothermal Data Repository (GDR) is the submission point for all data collected from researchers funded by the U.S. Department of Energy's Geothermal Technologies Office (DOE GTO). The DOE GTO is providing access to its geothermal project information through the GDR. The GDR is powered by OpenEI, an energy information portal sponsored by the U.S. Department of Energy and developed by the National Renewable Energy Laboratory (NREL).
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  1. We have calculated a chlorite dissolution rate equation at far from equilibrium conditions by combining new data (20 experiments at high temperature) with previously published data Smith et al. 2013 and Lowson et al. 2007. All rate data (from the 127 experiments) are tabulated inmore » this data submission. More information on the calculation of the rate data can be found in our FY13 Annual support (Carroll LLNL, 2013) which has been submitted to the GDR. The rate equation fills a data gap in geothemal kinetic data base and can be used directly to estimate the impact of chemical alteration on all geothermal processes. It is especially important for understanding the role of chemical alteration in the weakening for shear zones in EGS systems. « less
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