High-temperature and -pressure system for laser Raman spectroscopy of aqueous solutions

A high‐temperature, high‐pressure experimental system is presented that is compatible with a state‐of‐the‐art laser Raman spectrometer. The apparatus and associate electronics and valving, which allow Raman spectra acquisition from ambient conditions to 500 °C and 1‐kbar pressure in corrosive aqueous solutions, are described. Diamond windows and a titanium bodied optical design are used to obtain these conditions. Automatically controlled heating jackets have been built that allow ±0.4 °C temperature stability over this range. Raman spectra are presented that demonstrate the capabilities of this experimental apparatus for aqueous studies as a function of temperature and pressures.