Some Methodological Aspects of Studying Chemical Processes in Water Fluid Media

Some aspects of the experimental study of processes involving water fluids at temperatures approaching the critical (647 K) and above it in a static mode are considered. Particular attention is paid to the possible occurrence of artifacts and misinterpretations of the results associated with temperature gradients and uncontrolled effects of evaporation-condensation of water. The role of the walls of metal structural elements of the reactor (autoclave) as a catalyst for reactions involving water fluids and heat transfer processes on the measurements of thermal effects is analyzed. It is shown that a thermometric study of the dynamics of gas-phase reactions involving water vapor and supercritical fluid without measuring the pressure in the system and its chemical composition leads to uncertainty of the results and the inability to identify the most important kinetic features and mechanism of the process.