Unmet Need
As of 2019, the nitrogen oxides emissions in the United States is around 8 million tons per year. Nitrogen oxides (NOx) play a major role in several important environmental and human health effects. NOx reacts with organic compounds in sunlight and forms ozone. Additionally, NOx reacts in the air to form compounds contributing to acid deposition, which can damage forests and cause lakes and streams to acidify. Deposition of NOx affects nitrogen cycles, which contributes to the growth of algae, disrupting the chemical balance of nutrients in water. Because of the evident need to decrease NOx emissions, many different products have started to appear in the pipeline. The most common method for reducing NOx is the NOx adsorber. However, current absorbers contain platinum group metals (PGMs) that are expensive, limiting their practical application. Thus, there is a need for a cheaper method of absorbing NOx emissions.
Technology Overview
The inventors have created an NOx adsorber with a primary application of low-temperature absorption from exhaust gas. The adsorber comprises a manganese-based sorbent deposited on a high surface area carrier. The manganate oxide sorbent contains about 1-50% by weight of alkali-metal manganese based on the total weight of the material. Additionally, the invention includes an exhaust system comprising NOx adsorbers. The new sorbent serves better than PGM for NOx storage and release under the various operating conditions and different temperatures during the startup operation periods of automobiles.
Stage of Development
The invention has been developed and tested.
