The Role of a Catalyst
- A catalyst is a substance that increases the rate of reaction without taking part in the chemical reaction by providing the particles an alternative mechanism with a lower activation energy
A catalyst increases the rate of a reaction by providing an alternative pathway which has a lower activation energy
Importance of Catalysts
- Catalysts can be divided into two types:
- Homogeneous catalysts
- Heterogeneous catalysts
- Homogeneous means that the catalyst is in the same phase as the reactants
- For example, the reactants and the catalysts are all in solution
- Heterogeneous means that the catalyst is in a different phase to the reactants
- For example, the reactants are gases, but the catalyst used is a solid
Benefits of catalysts
- Catalysts speed up the rate of reaction, meaning the use of a catalyst may mean lower temperatures and pressures can be used
- This can save energy costs as there is reduced energy demand for providing high temperatures and less electrical pumping costs for producing the high pressures usually required
- This can mean fewer CO2 emissions from burning fossil fuels
- Catalysts can also enable different reactions to be used, with better atom economy and with reduced waste, or fewer undesired products or less use of hazardous solvents and reactants
- Catalysts are often enzymes, generating very specific products, and operating effectively close to room temperature and pressure
