What are the Common Types of Catalysts?

Catalysts are "reaction accelerators" in the chemical, environmental, and energy sectors, increasing reaction efficiency without consuming the catalyst itself.

Based on their composition and properties, common "industrial catalysts" are divided into four main categories, each with unique advantages and application scenarios. They are as follows:

Metal Catalysts

Advantages: High activity, strong selectivity for target reactions, and the ability to precisely activate specific chemical bonds.

Applications: Automotive exhaust purification, ammonia synthesis, and oil hydrogenation.

Function: In automotive exhaust, it converts harmful carbon monoxide and nitrogen oxides into harmless carbon dioxide and nitrogen. In ammonia synthesis, iron-based metal catalysts rapidly convert nitrogen and hydrogen into ammonia under mild conditions. In oil hydrogenation, nickel catalysts convert liquid oils into solid fats, meeting food processing needs.

Molecular sieve catalysts

Advantages: Their regular porous structure allows them to "screen" reactants by molecular size, and they also have a large surface area and high catalytic efficiency.

Applications: Catalytic cracking in petroleum refining and methanol-to-olefins.

Function: In petroleum refining, they can screen out small-molecule hydrocarbons, converting heavy oil into lighter fuels such as gasoline and diesel. In methanol-to-olefins, they can precisely convert methanol to ethylene and propylene, reducing unwanted byproducts.

Oxide catalysts

Advantages: Their excellent chemical stability and high-temperature resistance make them suitable for high-temperature continuous reaction conditions.

Applications: Industrial exhaust denitrification and methanol oxidation to formaldehyde.
Function: Vanadium-titanium oxide catalysts used in power plants react nitrogen oxides in exhaust gas with ammonia, converting them into pollution-free nitrogen and water. During methanol oxidation, copper oxide catalysts efficiently convert methanol to formaldehyde and are resistant to degradation at high temperatures.

Homogeneous Catalysts

Advantages: They mix well with the reaction system (mostly liquid), resulting in fast reaction rates and high catalytic efficiency.
Applications: Fine chemical synthesis, plastic monomer preparation.
Function: In the synthesis of pharmaceutical intermediates, organometallic homogeneous catalysts can accelerate olefin coupling reactions and rapidly produce the target compound. However, they can be difficult to separate and recover, and are currently optimized through immobilized catalysts.

Catalyst selection should consider reaction temperature, feedstock characteristics, and product requirements. These four types of catalysts collectively support efficient industrial production and are the core types of catalysts in the field of "chemical catalysts."

author: Hazel
date: 2025-10-23