Compact Combination NOx/O2 Sensors for High-Temperature Applications
Argonne National Laboratory
Contact ANL About This Technology
High-temperature potentiometric oxygen sensor with internal reference. The deformation bonding method produces pore-free, gas-tight joints between ceramic shell components while retaining material strength and ion conductivity.
Argonne, in collaboration with Ohio State University, has developed a compact, bi-functional NOx/O2 sensor with metal/metal oxide internal reference electrode for high-temperature applications. The O2 sensor is a previously developed zirconia O2 sensor with a sealed metal/metal oxide internal reference. The oxygen sensor does not need external air supply to operate and is less expensive than conventional technology. Combination sensors such as these are needed in combustion optimization processes and to successfully monitor NOx breakthrough, trigger NOx adsorption catalyst regeneration, and control reactant injection for NOx reduction.
DescriptionArgonne and Ohio State University researchers have coupled an oxygen sensor that has a palladium/palladium oxide (Pd/PdO) internal oxygen reference with two electrochemical techniques to measure total NOx to detect O2 and NOx simultaneously at high temperatures. A high-pressure and high-temperature bonding method creates an effective physical seal of Pd/PdO powder contained in an yttria-stabilized zirconia (YSZ) chamber. PtY is used to obtain total NOx measurements. The dissimilarity of catalytic activity between the sensing and reference electrodes generates strong potentiometric signals. Both amperometric- and potentiometric-type sensors show excellent O2 signal stability and total NOx response, although the potentiometric design provides more stable NOx detection.
BenefitsSuch sensors:
- Enable flexibility of placement in a combustion stream because they do not require reference gas plumbing
- Are assembled in such a way that miniaturization is possible
- Are low cost as compared to older, conventional sensing technology
- Enable the optimization of next-generation internal combustion engines and coal-fired power plants
- Monitor processes related to NOx breakthrough, catalyst regeneration, and reduction
Can be used in:
- Petrochemical plants
- Chemical plants
- Pulp and paper processing plants
- Blast and glass furnaces
- Internal combustion engines
- Coal-fired plants
- Environmental monitoring of exhaust gases
ID Number |
Title and Abstract | Primary Lab |
Date |
---|---|---|---|
Patent 6,974,070 |
Joining of advanced materials by superplastic deformation
A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques. |
Argonne National Laboratory | 12/13/2005
Issued |
Patent 7,413,109 |
Joining of advanced materials by superplastic deformation
A method for utilizing superplastic deformation with or without a novel joint compound that leads to the joining of advanced ceramic materials, intermetallics, and cermets. A joint formed by this approach is as strong as or stronger than the materials joined. The method does not require elaborate surface preparation or application techniques. |
Argonne National Laboratory | 08/19/2008
Issued |
Patent 8,057,652 |
High-temperature potentiometric oxygen sensor with internal reference
A compact oxygen sensor is provided, comprising a mixture of metal and metal oxide an enclosure containing said mixture, said enclosure capable of isolating said mixture from an environment external of said enclosure, and a first wire having a first end residing within the enclosure and having a second end exposed to the environment. Also provided is a method for the fabrication of an oxygen sensor, the method comprising confining a metal-metal oxide solid mixture to a container which consists of a single material permeable to oxygen ions, supplying an electrical conductor having a first end and a second end, whereby the first end resides inside the container as a reference (PO.sub.2).sup.ref, and the second end resides outside the container in the atmosphere where oxygen partial pressure (PO.sub.2).sup.ext is to be measured, and sealing the container with additional single material such that grain boundary sliding occurs between grains of the single material and grains of the additional single material. |
Argonne National Laboratory | 11/15/2011
Issued |
Development Stage | Availability | Published | Last Updated |
---|---|---|---|
Prototype - Prototypes have been built and tested. Argonne’s partner, Ohio State University, has checked the durability of the sensors for six months. Patents on the joining process are 6974070 (2005), 7413109 B2 (2008) and 7722731 (2010). Patent applications on the sensors are 11/228064 (2005), 11/861941 (2007), and 12/402216 (2008). | Available - This technology is available for license. Please contact Argonne for licensing information. | 04/05/2011 | 07/16/2013 |