Brief introduction of catalyst (definition/function/selectivity）
What should focus on:
- Coking or fouling
- Phase transformation
Their mechanism/ how to limit them
Can also introduce the influence of catalyst deactivation on industry, such as the expense on prevention of catalyst deactivation
limitations of the current technologies, for example, energy cost, high maintenance cost and try to understand how research is moving to solve these problems.
Chemical reactions proceed at different speeds. There are rapid reactions that can take place within a short period of time, while others may proceed at an annoyingly slow rate. Fortunately, scientists can alter the rates of chemical reactions to proceed at their own discretion (Satterfield, 1991). The substance used to increase the rate of a reaction is called a catalyst. A catalyst is defined as a substance that alters the rate of a reaction without itself being consumed in the process. This implies that the catalyst can be recovered at the end of the reaction since it is unreactive (Satterfield, 1991).
For example, in the Contact Process for the manufacture of sulfuric acid, vanadium (V) oxide (V2O5) is used as the catalyst in the conversion of SO2 to SO3. However, once the conversion process is complete, the catalyst is recovered for used in the subsequent process. Selectivity in catalysis refers to the ability of a catalyst to produce the desired product in a reaction. The implication here is that the catalyst may yield different products for the same reaction depending on the conditions it is subjected to (Satterfield, 1991). In general, different reactions have different substances that catalyze them to produce the desired fields.
Catalytic deactivation refers to the loss over time of the catalytic activity and/ selectivity during a catalytic process. It is an inevitable process that is arguably one of the major challenges facing catalytic processes in the production industry and research institutions (Bartholomew, 2001).