How Stable Are Carbon Monoxide Catalysts at Room Temperature?

At room temperature, carbon monoxide (CO) catalysts can efficiently convert toxic CO into harmless CO₂, but complex working conditions can easily lead to activity degradation. Stability needs to be ensured through scientific design and maintenance. High-quality room temperature CO catalysts, under reasonable working conditions, can maintain an activity retention rate of over 85% after continuous operation for 100,000 kilometers or 10,000 hours. However, if key influencing factors are ignored, deactivation problems can easily occur.

Key Factors Affecting the Stability of Room Temperature CO Catalysts

1. Loss of active components: If the active core of the catalyst (platinum, palladium, copper oxide, etc.) is not firmly bound to the support, it is prone to agglomeration or detachment due to airflow impact and thermal vibration, leading to a reduction in active sites. This is the main reason for stability degradation.

2. Poisoning interference: Impurities such as sulfides, nitrogen oxides, and heavy metal ions in the exhaust gas will form stable compounds with the active components, blocking the active sites.  Especially in environments with sulfide concentrations above 100 ppm, ordinary catalysts can experience a 30% decrease in activity within 200 hours.

3. Carbon deposition and humidity effects: Unburned hydrocarbons easily deposit carbon on the catalyst surface, covering the active sites; in high-humidity environments, water vapor adsorption will inhibit the contact between CO and the active sites, and in the long term, it may also lead to the collapse of the support structure. 

Core Measures to Mitigate Stability Degradation

To address the factors mentioned above, stability can be ensured through a dual approach of technical design and usage management: 

 First, employ active component anchoring technology, using a composite carrier to fix the active components via chemical bonds, and incorporating a core-shell structure to reduce aggregation; 

second, add anti-poisoning components to intercept heavy metals and decompose sulfides; 

third, select a honeycomb-shaped porous carrier with a hydrophobic coating on the surface to reduce carbon deposition and water vapor adsorption; 

fourth, control operating conditions to avoid contact between the catalyst and high-concentration impurity gases, and regularly clean surface deposits.

Practical Cases of Room-Temperature CO Catalyst Stability

A commercial vehicle company installed a room-temperature CO catalyst on diesel trucks. Under the conditions of high humidity and frequent short-distance cold starts in southern China, after 150,000 kilometers of continuous operation, the CO purification efficiency decreased from an initial 99% to 95%, with an activity retention rate of 88%. After disassembly, there was no significant aggregation of active components, the carrier structure remained intact, and no poisoning or deactivation occurred.

An electronics factory used a room-temperature CO catalyst to treat welding exhaust gas. After 20,000 hours of continuous operation, the purification efficiency decreased from 98% to 92%, with an activity degradation of only 6%, far below the industry standard of 20%, allowing for continuous use without catalyst replacement.

The stability of room-temperature CO catalysts is affected by factors such as active components, impurities, and operating conditions. However, through scientific technical design and standardized use, long-term stable operation can be achieved.  It possesses extremely high practical value in automotive and industrial applications, and its stability performance already meets the core requirements for commercialization.

Author: Hazel
Date: 2025-12-24