CO2 solubility in multi-component brines containing NaCl, KCl, CaCl2 and MgCl2 at 297 K and 1–14 MPa

Abstract Carbon captureand storage(CCS) is a strategy to reduce greenhouse gas emissions by capturing CO 2 from point sources and injecting it into deep saline formations. Over time, the injected CO 2 dissolves into the saline pore waters forming an aqueous solution that is both a negatively buoyant fluid (sinks) and geologically reactive. Deep saline aquifers are geochemically complex and experimental studies have several gaps in solubility measurements for the multi-component brinesthat are needed to model the fate and reaction of CO 2 . New experimental dataare presented here for three of the most common salts found in potential carbon storage locations, NaCl, KCl and MgCl 2 , as well as multi-salt brinesincluding these salts and CaCl 2 . These experimental dataare compared with available literature data and models used to predict CO 2 solubility in single- and multi-component brines. Comparison of the experimental datawith the models indicates that the reactor does work in the range of temperature, pressure and salinity presented here and that available models can accurately predict the solubility of CO 2 in various salt solutions.