Catalyst and method of manufacture

Abstract

A catalyst system comprising a first catalytic composition comprising a homogeneous solid mixture containing at least one catalytic metal and at least one metal inorganic support. The pores of the solid mixture have an average diameter in a range of about 1 nanometer to about 15 nanometers. The catalytic metal comprises nanocrystals.

Description

BACKGROUND[0001]The systems and techniques described include embodiments that relate to catalysts. They also include embodiments that relate to the making of catalysts and systems that may include catalysts.[0002]Exhaust streams generated by the combustion of fossil fuels, such as in furnaces, ovens, and engines, contain various potentially undesirable combustion products including nitrogen oxides (NOx), unburned hydrocarbons (HC), and carbon monoxide (CO). NOx, though thermodynamically unstable, may not spontaneously decompose in the absence of a catalyst. Exhaust streams may employ exhaust treatment devices to remove NOx from the exhaust stream.[0003]Examples of exhaust treatment devices include catalytic converters (e.g., three-way catalyst, oxidation catalysts, selective catalytic reduction (SCR) catalysts, and the like), evaporative emission devices, scrubbing devices (e.g., hydrocarbon (HC), sulfur, and the like), particulate filters / traps, adsorbers / absorbers, plasma reactors...

AI Technical Summary

Problems solved by technology

However, the presence of ammonia may be undesirable, and there may be some ammonia slip due to imperfect distribution of reacting gases as well as due to incomplete ammonia consumption.

Further, ammonia solutions require an extra storage tank and are subject to freezing at cold ambient temperatures.

However, the conversion efficiency may be reduced outside the temperature range of 300 degrees C. to 400 degrees C. In addition, this technique may have HC-slip over the catalyst, transportation and on-site bulk storage of hydrocarbons, and possible atmospheric release of the HC.

Images