What is meant by heterogeneous catalysis? - Leaving Cert Chemistry - Question i - 2013

Heterogeneous catalysis refers to a process in which the reactants (or substrates) and the catalyst are in different phases. Typically, this involves solid catalysts with gaseous or liquid reactants.

In this context, the solid catalyst provides a surface for the reactants to interact. This interaction occurs at the boundary between the reactants and the catalyst, which plays a crucial role in facilitating the chemical reaction.

To clarify further, in heterogeneous catalysis:

• The reactants and the catalyst exist in distinct phases (e.g., solid vs. gas or liquid).
• The interface between the two phases is where the reaction predominantly takes place, allowing for efficient interaction and transfer of molecules.

This type of catalysis is common in various industrial processes, such as hydrogenation and catalytic converters in automobiles.