How to Efficiently Decompose Ozone in Winter?

In winter, low temperatures and low light conditions significantly reduce the natural decomposition rate of ozone, and residual ozone can easily cause multiple hazards. Ozone decomposition and low-temperature ozone treatment have become a key focus of environmental protection in winter. Ozone mainly comes from natural and anthropogenic sources. Stratospheric ozone is the Earth's "protective shield," while near-ground ozone is mostly generated by photochemical reactions of nitrogen oxides (NOx) and volatile organic compounds (VOCs) from vehicle exhaust and industrial emissions.  The enclosed environment in winter makes its accumulation more likely.

Ozone is not directly emitted, but is generated from nitrogen oxides and volatile organic compounds under the action of sunlight. These precursors come from sources including vehicle exhaust, industrial production, and fossil fuel combustion.

The World Health Organization recommends an ozone guideline value of 100 µg/m³, while summer ozone levels often reach 2-3 times this value. During high-altitude cruising of aircraft, the ozone concentration in the cabin can even reach 0.5 ppm. Scientific data shows that even exposure to ozone concentrations below 0.3-0.5 ppm can lead to significant declines in lung function. Prolonged exposure can also trigger more serious respiratory diseases such as bronchitis and emphysema.

Common methods for dealing with ozone pollution include physical adsorption, thermal decomposition, photolysis, and catalytic decomposition. Activated carbon adsorption was once a common method, but it suffers from limited capacity, requires frequent replacement, and may pose safety hazards at high ozone concentrations.

Thermal decomposition technology requires heating the gas to high temperatures, consuming a large amount of energy, resulting in high operating costs, and making it difficult to widely apply in situations requiring continuous operation.

Photolysis technology relies on specific wavelengths of ultraviolet light; the equipment is expensive, and its efficiency is affected by various factors. These traditional methods all face the dilemma of significantly reduced efficiency under low winter temperatures, especially when the temperature is below 0°C, where the performance loss is particularly noticeable.

Catalytic decomposition technology, through the active sites on the catalyst surface, can efficiently decompose ozone at room temperature or even low temperatures without requiring external energy input. The biggest advantage of this technology is that once the catalyst is prepared, the operating cost is almost zero, and it does not require complex external conditions.

The core material of the catalyst determines its performance. Manganese-based catalysts are one of the most widely studied systems. By precisely controlling the preparation method, scientists can adjust their surface properties and microstructure, thereby improving low-temperature activity.

Zeolite-encapsulated manganese oxide cluster technology is one of the most groundbreaking advancements in recent years. Studies show that this catalyst, operating at a space velocity of up to 720,000 h⁻¹ at a low temperature of -5°C, can still maintain an ozone decomposition efficiency of over 95% and operate stably for 98 hours.

More importantly, this catalyst can be regenerated under mild conditions (180°C air treatment for 1 hour), providing the possibility for long-term application.

In a winter wastewater treatment project in a chemical industrial park, the use of a Mn-Ce-based ozone decomposition catalyst resulted in an ozone decomposition efficiency of 99.8%, reducing the COD concentration in the effluent from 300 mg/L to below 100 mg/L, with a removal rate exceeding 67%, and stable operation without degradation even at a low temperature of -5°C. Another municipal wastewater treatment plant uses a honeycomb ceramic carrier catalyst to treat ozone off-gas.  Even with humidity exceeding 90% in winter, it maintains a decomposition efficiency of over 95%, ensuring the off-gas ozone concentration meets standards.  Operating costs are 40% lower than the thermal decomposition method.

Selecting a high-quality ozone decomposition catalyst requires attention to low-temperature activity and moisture resistance. Manganese-based composite oxide catalysts perform exceptionally well under winter conditions and have a service life of over 5 years. This efficient catalytic decomposition technology not only solves the problem of ozone accumulation in winter but also helps companies achieve environmental compliance and cost optimization, making it an essential solution for winter ozone treatment.

Author: Hazel
Date: 2026-01-07