The Linseis STA HP Series enables measurements under controlled elevated pressure.
In certain reactions, such as decomposition, adsorption, and desorption, the behavior of samples and materials depends heavily on atmospheric conditions, since many of these reactions are pressure-dependent.
These curves show a comparative measurement of the decomposition of calcium oxalate hydrate under pressure (20 bar, red curve) versus under atmospheric conditions (blue curve).
A clear pressure dependence can be observed for decomposition steps 1 (loss of water) and 3 (loss of carbon dioxide).
Decomposition steps 1 and 3 are shifted to higher temperatures under increased pressure.
The second step is the irreversible conversion of organic oxalate to inorganic carbonate, during which carbon monoxide is released. Since this reaction is irreversible, it is not pressure-dependent.
