How are ozone decomposition catalysts made?

Although ozone plays a protective role in the atmospheric ozone layer, excessive levels in indoor or industrial environments can pose health risks. Therefore, ozone decomposition catalysts have become key materials in the environmental protection field. Their production process directly affects decomposition efficiency and stability. The following is an analysis of several mainstream preparation methods and their applicable scenarios.

Impregnation Method: The Mainstream Choice in Air Purification

The impregnation method uses activated carbon, alumina, or other materials as carriers. Active components (nitrates or sulfates) such as manganese and copper are dissolved in the impregnation method, which allows the carrier to fully absorb the solution. The catalyst is then dried and calcined (at 300-500°C).
Applications: Small devices such as household air purifiers and vehicle ozone filters.
Advantages: Simple process, low cost, and controllable catalytic efficiency by adjusting the carrier pore size, making it suitable for mass production.
Disadvantages: Active components are easily shed, resulting in a short lifespan (typically 6-12 months), and a significant decrease in efficiency in high humidity environments.

Co-precipitation Method: An Efficient Solution for Industrial Waste Gas Treatment

The co-precipitation method combines a solution of metal salts such as manganese, cobalt, and nickel with a precipitant (such as sodium hydroxide) to form a composite hydroxide precipitate. This is then washed and calcined (at 400-600°C) to form a multi-metal oxide catalyst.

Applications: Industrial waste gas denitrification and desulfurization systems, and ozone exhaust treatment in sewage treatment plants. Advantages: Uniform dispersion of active components, resistance to high-concentration ozone, and a service life of up to 2-3 years.

Disadvantages: Strict control of precipitation conditions (pH and temperature), high equipment investment, and product agglomeration that requires crushing.

Sol-Gel Method: The preferred process for high-precision applications

The sol-gel method involves hydrolyzing a metal alkoxide to form a sol. After gelation, a carrier powder is added, followed by low-temperature drying and high-temperature calcination (500-700°C) to produce a high-surface-area catalyst.
Applications: Medical cleanrooms, semiconductor workshops, and other locations with stringent requirements for ozone residual levels.
Advantages: High catalytic activity (ozone decomposition rate >99%), excellent low-temperature performance (effective even at -10°C), and strong resistance to poisoning.
Disadvantages: High raw material costs (metal alkoxides are expensive), long production cycles (3-5 days), and difficulty in large-scale production.

Plasma-Assisted Method: An emerging, efficient preparation technology

The plasma-assisted method involves a chemical reaction between a metal precursor and a carrier in a low-temperature plasma environment to directly generate a supported catalyst. Applications: Real-time ozone purification in confined spaces such as high-speed rail carriages and airline cabins.
Advantages: No high-temperature calcination required, low energy consumption, more active sites on the catalyst surface, and fast response time.
Disadvantages: Complex equipment, currently only suitable for small-batch production, and costs 2-3 times higher than traditional methods.

Author: Hazel
Date: 2025-09-19