US20160121307A1 - Metal tungstates for use as nitrogen oxides reduction catalysts - Google Patents

Metal tungstates for use as nitrogen oxides reduction catalysts Download PDF

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Publication number
US20160121307A1
US20160121307A1 US14/529,491 US201414529491A US2016121307A1 US 20160121307 A1 US20160121307 A1 US 20160121307A1 US 201414529491 A US201414529491 A US 201414529491A US 2016121307 A1 US2016121307 A1 US 2016121307A1
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Prior art keywords
nox
nitrogen oxide
catalyst
oxygen
reduction catalyst
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US14/529,491
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Inventor
Hongfei Jia
Charles A. Roberts
Mitsuru Sakano
Keiichi Minami
Torin Peck
Paul T. Fanson
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Toyota Motor Corp
Toyota Motor Engineering and Manufacturing North America Inc
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Toyota Motor Corp
Toyota Motor Engineering and Manufacturing North America Inc
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Priority to US14/529,491 priority Critical patent/US20160121307A1/en
Assigned to TOYOTA MOTOR ENGINEERING & MANUFACTURING NORTH AMERICA, INC. reassignment TOYOTA MOTOR ENGINEERING & MANUFACTURING NORTH AMERICA, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: FANSON, PAUL T., JIA, HONGFEI, Peck, Torin, ROBERTS, CHARLES A.
Assigned to TOYOTA JIDOSHA KABUSHIKI KAISHA reassignment TOYOTA JIDOSHA KABUSHIKI KAISHA ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MINAMI, KEIICHI, SAKANO, MITSURU
Priority to DE102015116735.2A priority patent/DE102015116735A1/de
Priority to CN201510675436.5A priority patent/CN105561977B/zh
Priority to JP2015214200A priority patent/JP6804835B2/ja
Publication of US20160121307A1 publication Critical patent/US20160121307A1/en
Priority to US15/875,646 priority patent/US10293328B2/en
Abandoned legal-status Critical Current

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Definitions

  • the invention relates to a catalyst for reducing nitrogen oxide (NOx) and to a process for reducing nitrogen oxide (NOx).
  • NOx nitrogen oxide
  • Diesel Engines creates nitrogen oxide (NOx) that contributes to smog and other forms of environmental pollution. NOx should be removed from the exhaust streams of these engines in order to protect the environment and satisfy government regulations.
  • Current 3-way catalyst converter technology may be used to remove NOx in automotive exhaust under certain limiting conditions. For example, 3-way catalysts operate at high temperatures greater than 300 degrees C.
  • 3-way catalysts contain a large quantity of precious metals such as platinum, rhodium, and palladium. Further, prior art catalysts may have difficulty in reacting with NOx in the presence of oxygen.
  • a nitrogen oxide (NOx) reduction catalyst that includes a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu.
  • a nitrogen oxide (NOx) reduction catalyst that includes a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co and Cu wherein the catalyst reduces nitrogen oxide (NOx) in an oxygen rich environment including hydrocarbon fuel.
  • a nitrogen oxide (NOx) reduction catalyst that includes a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Ni and Co wherein the catalyst reduces nitrogen oxide (NOx) in an oxygen deficient environment including hydrocarbon fuel.
  • a process of reducing nitrogen oxide (NOx) including the steps of: providing a gaseous exhaust mixture including nitrogen oxide (NOx) and hydrocarbon fuel, providing a nitrogen oxide (NOx) reduction catalyst including a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu, and contacting the gaseous exhaust mixture with a surface of the nitrogen oxide (NOx) reduction catalyst forming nitrogen, water and carbon dioxide.
  • FIG. 1A is a scanning electron microscopy (SEM) image of MnWO 4 nanoparticles
  • FIG. 1B is a scanning electron microscopy (SEM) image of CoWO 4 nanoparticles
  • FIG. 1C is a scanning electron microscopy (SEM) image of FeWO 4 nanoparticles
  • 1 D is a scanning electron microscopy (SEM) image of NiWO 4 nanoparticles
  • 1 E is a scanning electron microscopy (SEM) image of CuWO 4 nanoparticles
  • FIG. 2 is a plot of the particle size and corresponding specific surface area (BET SSA) for MWO 4 wherein M is selected from Mn, Fe, Co, Ni, and Cu;
  • FIG. 3 is a graphical depiction of the testing protocol used for activity tests of the nitrogen oxide (NOx) reduction catalyst
  • FIG. 4 is a plot of the NO conversion as a function of temperature for the nitrogen oxide (NOx) reduction catalyst without oxygen;
  • FIG. 5 is a plot of the NO conversion as a function of temperature for the nitrogen oxide (NOx) reduction catalyst with oxygen;
  • FIG. 6 is a plot of the NO conversion as a function of oxygen conversion for the nitrogen oxide (NOx) reduction catalyst
  • FIG. 7 is a plot of the NO, oxygen and hydrocarbon conversion as a function of the temperature for MnWO 4 ;
  • FIG. 8 is a plot of the nitrogen and nitrogen dioxide counts as a function of temperature for MnWO 4 ;
  • FIG. 9 is a plot of the NO and hydrocarbon conversion as a function of the temperature for NiWO 4 ;
  • FIG. 10 is a plot of the nitrogen and nitrogen dioxide counts as a function of temperature for NiWO 4 ;
  • FIG. 11 is an XRD plot of MWO 4 wherein M is selected from Mn, Fe, Co, Ni, and Cu;
  • FIG. 12 is a graphical representation of a reduction mechanism for the nitrogen oxide (NOx) reduction catalyst in an oxygen rich condition
  • FIG. 13 is a graphical representation of a reduction mechanism for the nitrogen oxide (NOx) reduction catalyst in an oxygen deficient condition.
  • the present disclosure provides a method of forming, process of reducing nitrogen oxide (NOx) and/or catalyst composition for the reduction of nitrogen oxide (NOx) to generate nitrogen, water and carbon dioxide.
  • the catalyst may include a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu.
  • M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu.
  • the catalyst may be utilized in oxygen rich environments and oxygen deficient environments. This catalyst provides a precious metal free catalyst that allows for reaction in a variety of conditions unlike most 3-way catalysts that operate only in narrowly defined conditions.
  • the catalyst allows the selective interaction of nitrogen oxide (NOx) with a surface of the catalyst in oxygen rich and oxygen deficient environments in contrast to current prior art catalysts.
  • the process includes providing a gaseous exhaust mixture including nitrogen oxide (NOx) and hydrocarbon fuel; providing a nitrogen oxide (NOx) reduction catalyst including a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu; and contacting the gaseous exhaust mixture with a surface of the nitrogen oxide (NOx) reduction catalyst forming nitrogen, water and carbon dioxide.
  • NOx nitrogen oxide
  • hydrocarbon fuel providing a nitrogen oxide (NOx) reduction catalyst including a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu
  • MWO 4 transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu
  • the nitrogen oxide (NOx) reduction catalyst includes the transition metal tungstate of the formula MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co, Ni, and Cu and includes a crystalline structure.
  • the catalyst can include a plurality of transition metal tungstate nanoparticles. In some instances, the nanoparticles are uniform in size and can have an average particle size of 10 to 60 nanometers as best shown in FIGS. 1A-E and FIG. 2 .
  • the catalyst may be used in a variety of conditions such as oxygen rich and oxygen deficient conditions.
  • the catalyst may have the formula: MWO 4 wherein M is selected from Mn, Fe, Co and Cu and the catalyst reduces nitrogen oxide (NOx) in an oxygen rich environment.
  • the catalyst may have the formula: MWO 4 wherein M is selected from Ni and Co and the catalyst reduces nitrogen oxide (NOx) in an oxygen deficient environment.
  • a process of forming a nitrogen oxide (NOx) reduction catalyst including the steps of: providing metal salts of the transition metal including Co(NO 3 ) 2 , MnCl 2 , Fecl 2 , Ni(NO 3 ) 2 or Cu(SO 4 ) 4 ; providing Na 2 WO 4 ; combining the metal salt and Na 2 WO 4 forming a solution; exposing the solution to a source of microwave energy and initiating a hydrothermal reaction forming MWO 4 .
  • the exposing step may include exposure to microwave energy for various periods of time to elevate the temperature or heat the solution to a desired temperature range.
  • the exposing step may include exposing the solution to microwave energy from less than one minute to 60 minutes. In one aspect, the exposing step may be from 1 to 10 minutes at a power of 800 Watts. The exposing step may raise the temperature of the solution to a temperature of from 80 to 300 degrees C. Following the exposing step, the solution may be cooled and then washed and dried. Following the drying step, the catalyst material may be calcined in air at 350-700 degrees C. for 60 minutes.
  • the catalyst may include a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Mn, Fe, Co and Cu wherein the catalyst reduces nitrogen oxide (NOx) with hydrocarbon fuel.
  • FIG. 12 there is shown a graphical depiction of the catalyst reaction in an oxygen rich condition.
  • NOx nitrogen oxide
  • the reaction mechanism as described may reduce the overall activation energy barrier for (NOx) or (NO) reduction in typical prior art catalysts.
  • the catalyst may include a transition metal tungstate having the formula: MWO 4 wherein M is selected from the group consisting of Ni and Co wherein the catalyst reduces nitrogen oxide (NOx) an oxygen deficient environment including hydrocarbon fuel.
  • FIG. 13 there is shown a graphical depiction of the catalyst reaction in an oxygen deficient condition.
  • the tube was cooled by forced air flow.
  • the resulting product was rinsed with DI water multiple times on a centrifuge followed by vacuum drying overnight at 60 degrees C.
  • the catalyst material was calcined in air at 550 degrees C. for 60 minutes.
  • MWO 4 material includes discrete particles having a size ranging from 10-60 nm. The particles have a specific surface area of from 4.9 to 28.2 m 2 /g as depicted in FIG. 2 .
  • X-ray diffraction (XRD) data is shown in FIG. 11 and shows a crystalline structure for the catalyst materials.
  • the activity testing was performed in a laboratory scale packed bed reactor (PID Eng&Tech Microactivity-Reference). Activity was determined for NO reduction by the hydrocarbon propylene (C3H6). Activity testing was performed under stoichiometric conditions both in oxygen deficient and oxygen rich conditions. As depicted in FIG. 3 , under oxygen deficient conditions, the stoichiometric ratio of NO:C3H6 is 9:1, and under oxygen rich conditions, the stoichiometric ratio of NO:C3H6:O2 is 3:1:3. Also depicted in FIG.
  • FIG. 4 there is shown a plot of the NO conversion over the catalyst samples in an oxygen deficient condition in which no oxygen was added to the reactor.
  • the NiWO 4 and CoWO 4 samples exhibited NO reduction in the oxygen deficient condition.
  • the reduction of NOx in the oxygen deficient condition verifies the selective interaction of NO with the catalyst surface in the absence of oxygen.
  • FIG. 5 there is shown a plot of the NO conversion over the catalyst samples in an oxygen rich condition in which oxygen was added to the reactor.
  • the MnWO 4 , FeWO 4 , CoWO 4 and CuWO 4 samples exhibited NO reduction in the oxygen rich condition.
  • the reduction of NOx in the oxygen rich condition verifies the selective interaction of NO with the catalyst surface in the presence of oxygen.
  • FIG. 6 depicts a plot of the NO conversion over the catalyst samples as a function of the O 2 conversion under the conditions of stoichiometric NO reduction under oxygen rich conditions in which oxygen was added to the reactor.
  • the selectivity herein refers to the ability of the catalyst surface to selectively interact with NO gas rather than O 2 gas.
  • the MnWO 4 sample displays an almost 1 to 1 selectivity of NO to O 2 .
  • the ability of the catalyst surface to perform the desired NO reduction reaction in the presence of oxygen provides an improvement over current prior art catalysts.
  • FIG. 7 there are shown NO, C3H6, and O2 conversions as a function of temperature for MnWO 4 in an oxygen rich condition in which oxygen was added to the reactor. As can be seen in the figure, the NO conversation exceeds 90% for the sample. The NO conversion dropped as O 2 was depleted at higher temperatures.
  • FIG. 8 indicates that reduction of NO under oxygen rich conditions results in the production of N 2 with trace amounts of NO 2 also present.
  • FIG. 9 there are shown NO and C3H6 conversions as a function of temperature for NiWO 4 in an oxygen deficient condition in which no oxygen was added to the reactor. As can be seen in the figure, the NO conversation exceeds 80% for the sample.
  • FIG. 10 indicates that reduction of NO under oxygen deficient conditions results in the production of N 2 and with no production of NO 2 .

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10682632B2 (en) * 2018-06-26 2020-06-16 Uop Llc Transition metal tungstate material
US10688479B2 (en) * 2018-06-26 2020-06-23 Uop Llc Crystalline transition metal tungstate
US10882030B2 (en) * 2017-08-25 2021-01-05 Uop Llc Crystalline transition metal tungstate

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP6439761B2 (ja) * 2016-08-09 2018-12-19 トヨタ自動車株式会社 ＮＯｘ吸蔵還元触媒の製造方法
US10737248B2 (en) * 2018-06-26 2020-08-11 Uop Llc Crystalline transition metal tungstate
JP7181820B2 (ja) * 2019-03-14 2022-12-01 日本碍子株式会社 多孔質セラミック構造体

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2006109849A1 (ja) * 2005-04-11 2006-10-19 Valtion Teknillinen Tutkimuskeskus 窒素酸化物を接触還元するための触媒、触媒構造体及び窒素酸化物を接触還元するための方法
US7759280B2 (en) * 2006-09-20 2010-07-20 Basf Corporation Catalysts, systems and methods to reduce NOX in an exhaust gas stream
US20080095682A1 (en) * 2006-10-19 2008-04-24 Kharas Karl C Ce-Zr-R-O CATALYSTS, ARTICLES COMPRISING THE Ce Zr R O CATALYSTS AND METHODS OF MAKING AND USING THE Ce-Zr-R-O CATALYSTS
JP5691779B2 (ja) * 2010-12-07 2015-04-01 株式会社デンソー 排ガス浄化装置
CN102380378A (zh) * 2011-09-08 2012-03-21 大连理工大学 一种高富氧条件下低温选择还原消除氮氧化物催化剂及其应用
CN103007925A (zh) * 2012-12-21 2013-04-03 中国科学院生态环境研究中心 一种锰钨复合氧化物催化剂、制备方法及其用途
JP6273859B2 (ja) * 2014-01-27 2018-02-07 株式会社豊田中央研究所 三元触媒及びそれを用いた排ガス浄化方法
CN103991913A (zh) * 2014-05-29 2014-08-20 陕西科技大学 一种采用微波水热法制备CoWO4 纳米粉体材料的方法

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Zawawi et al (Structural and optical characterization of metal tungstates (MWO4; M=Ni, Ba, Bi) synthesized by a sucrose-templated method. Chem. Cen. J (2013) 7:80, pp. 1-10 and published online on May 1, 2013). *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US10882030B2 (en) * 2017-08-25 2021-01-05 Uop Llc Crystalline transition metal tungstate
US10682632B2 (en) * 2018-06-26 2020-06-16 Uop Llc Transition metal tungstate material
US10688479B2 (en) * 2018-06-26 2020-06-23 Uop Llc Crystalline transition metal tungstate

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