US 2019/0055868 A1 · AMMONIA GENERATION FROM ENGINE EXHAUST AT AMBIENT CONDITIONS USING WATER-GAS SHIFT AND AMMONIA SYNTHESIS CATALYSTS

Abstract

Systems and methods described herein relate to generating ammonia from engine exhaust instead of or in addition to using on-board storage tank(s) and/or doser(s) to provide the necessary chemical reagents for purification of the exhaust stream. Systems and methods for generating ammonia and/or hydrogen from engine exhaust in exhaust aftertreatment systems under ambient conditions comprise at least one water-gas shift (WGS) catalyst and at least one ammonia synthesis catalyst (AMS catalyst) positioned downstream of the WGS catalyst. The WGS catalyst is configured, using the engine exhaust gas as an input, to generate hydrogen used by the AMS catalyst as inputs to generate ammonia and/or hydrogen. The ammonia and/or hydrogen thus generated are used downstream in ammonia- and/or hydrogen-based selective catalytic reduction catalysts (SCR).

Claims21

Dependent claims

A method for treating exhaust gas in an aftertreatment system, the method comprising:

receiving a quantity of exhaust gas from an engine, the quantity of exhaust gas containing a quantity of water, a quantity of nitrogen, and a quantity of carbon monoxide;
generating a quantity of hydrogen from the quantity of water and the quantity of carbon monoxide using a water-gas shift catalyst;
generating, using an ammonia synthesis catalyst, a quantity of ammonia using the quantity of hydrogen generated by the water-gas shift catalyst from the quantity of exhaust gas and the quantity of nitrogen from the quantity of exhaust gas, as an input;
and
feeding, by an insertion conduit, the quantity of ammonia, generated by the ammonia synthesis catalyst from the quantity of hydrogen generated by the water-gas shift catalyst, and the quantity of nitrogen from the quantity of exhaust gas to a selective catalytic reduction catalyst.

2 more elements

An exhaust aftertreatment system comprising:

an exhaust conduit structured to receive a quantity of exhaust gas from an engine, the quantity of exhaust gas containing a quantity of water, a quantity of nitrogen, and a quantity of carbon monoxide;
a water-gas shift catalyst structured to generate at least a quantity of hydrogen from the quantity of water and the quantity of carbon monoxide;
an ammonia synthesis catalyst structured to generate at least a quantity of ammonia using the quantity of hydrogen generated by the water-gas shift catalyst and the quantity of nitrogen from the quantity of exhaust gas as an input;
and
an insertion conduit structured to feed the quantity of ammonia, generated by the ammonia synthesis catalyst from the quantity of hydrogen generated by the water-gas shift catalyst and the quantity of nitrogen from the quantity of exhaust gas, to a selective catalytic reduction catalyst.

2 more elements

Dependencies are inferred from the claim text.

Ammonia generation from engine exhaust at ambient conditions using water-gas shift and ammonia synthesis catalysts

Life of this patent

Ammonia generation from engine exhaust at ambient conditions using water-gas shift and ammonia synthesis catalysts

Life of this patent

Abstract

Claims21