Special Design and Technology Bureau “Catalyst” JSC (Russian Federation) has been granted Eurasian Patent No. 053522 B1 for a dual-action catalyst for industrial gas purification.

The invention is designed to address one of the key environmental problems associated with the removal of nitrogen oxides (NOx) – excess ammonia (NH₃) emissions.

Nitrogen oxides are among the most dangerous air pollutants. They contribute to acid rain, cause respiratory diseases, and play a role in the destruction of the ozone layer. The primary industrial method for removing them is selective catalytic reduction using ammonia. However, this process requires the injection of excess NH₃ (10-15% above the required amount), and this excess inevitably enters the atmosphere.

For a long time, ammonia was considered relatively safe, but modern research has proven otherwise: in the atmosphere, it is re-oxidized to NOx, negating the purification effect and contributing to the formation of toxic aerosols. As a result, environmental regulators in EAEU countries effectively equate the negative impact of NH₃ with that of NOx. Companies find themselves in a difficult situation: they must either under-treat the gases or pay fines and build expensive additional ammonia oxidation units.

The new catalyst solves both problems simultaneously: it reduces NOx and oxidizes residual ammonia in a single reactor.

Key features of the solution:

• a special composition with added manganese, which catalyzes the oxidation of NH₃ into harmless nitrogen and water;
• a bimodal pore structure (small pores for high activity and large pores for rapid gas access), resistant to sulfur and water vapor;
• high mechanical strength (94% abrasion resistance) and a long service life without regeneration.

Tests have shown that at temperatures of 220-360°C, the catalyst achieves NOx conversion rates of 94-99.9% while simultaneously removing 70-97% of residual ammonia.

Thus, this solution eliminates the need for additional purification stages, reduces capital costs, and ensures consistent compliance with environmental standards.