The changes in the properties of humic acids under high temperature influence

The change in the properties of humic acids when exposed to high temperatures has been studied. In this work, the process of hydropyrolysis of HAs was studied and their thermal stability was assessed. Experimental data on the thermal destruction of alkaline solutions of humic acid at 150 °С, 200 °С, 250 °С and saturated water vapor pressure were obtained. It has been shown that in the process of hydropyrolysis the degree of condensation of molecules changes, the number of functional groups noticeably increases and the values of weight-average molecular masses decrease. The obtained experimental results made it possible to calculate the parameters of the thermal stability of humic acids.