Development of an electrochemically integrated SR-GIXRD flow cell to study FeCO3 formation kinetics

An electrochemically integrated Synchrotron Radiation-Grazing Incidence X-Ray Diffraction (SR-GIXRD) flow cell for studying corrosion product formation on carbon steel in carbon dioxide (CO2)-containing brines typical of oil and gas production has been developed. The system is capable of generating flow velocities of up to 2 m/s at temperatures in excess of 80 °C during SR-GIXRD measurements of the steel surface, enabling flow to be maintained over the course of the experiment while diffraction patterns are being collected. The design of the flow cell is presented, along with electrochemical and diffraction pattern transients collected from an initial experiment which examined the precipitation of FeCO3 onto X65 carbon steel in a CO2-saturated 3.5 wt. % NaCl brine at 80 °C and 0.1 m/s. The flow cell is used to follow the nucleation and growth kinetics of FeCO3 using SR-GIXRD linked to the simultaneous electrochemical response of the steel surface which were collected in the form of linear polarisation res...