摘要:
A catalytic structure can comprise a catalyst and one or more radical scavengers. Each radical scavenger can comprise one or more nanoparticles. Each nanoparticle can be formed as an oxide or oxynitride and can comprise at least one metal selected from titanium (Ti), zirconium (Zr), hafnium (Hf), rutherfordium (Rf), vanadium (V), niobium (Nb), tantalum (Ta), and dubnium (Db). In some embodiments, the radical scavenger can be used in an oxygen reduction reaction, for example, to decompose hydrogen peroxide into water and oxygen. In some embodiments, the catalytic structure with radical scavengers can exhibit enhanced durability, for example, when incorporated into a proton-exchange membrane (PEM) fuel cell.
摘要:
The present disclosure provides SCR catalyst compositions capable of reducing nitrogen oxide (NOx) emissions in engine exhaust. The catalyst compositions include a reducible metal oxide support containing ceria, one or more transition metal oxides as a redox promotor; and an oxide of niobium, tungsten, silicon, molybdenum, or a combination thereof as an acidic promotor. The redox promotor and the acid promotor are both supported on the reducible metal oxide support. Further provided are SCR catalyst articles coated with such compositions, processes for preparing such catalyst compositions and articles, an exhaust gas treatment system including such catalyst articles, and methods for reducing NOx in an exhaust gas stream using such catalyst articles and systems.
摘要:
Herein is disclosed a method of producing a ceramic support suitable for a catalyst, the method comprising providing a porous ceramic structure, comprising a body portion with a monomodal macropore structure, wherein the macropores comprises a first mean pore size; washcoating the porous ceramic structure using a suspension comprising oxide and/or hydroxide nanoparticles and drying and calcinating the washcoated porous ceramic structure at a temperature below the melting point of the nanoparticles. In addition, the ceramic support and its structure is disclosed.
摘要:
The present disclosure provides for a composite catalyst comprising a first catalytic material incorporated with a second catalytic material, wherein the first catalytic material comprises carbon doped with (i) nitrogen and (ii) at least one non-precious transition metal, and wherein the second catalytic material comprises a carbon-based supporting material incorporated with platinum nanoparticles. The present disclosure also provides for a method of producing the composite catalyst, wherein the method may comprise providing a mixture comprising the first catalytic material and the second catalytic material, and subjecting the mixture to a size reduction step. The first catalytic material and a method of producing the first catalytic material are disclosed herein.
摘要:
본 발명은 배기가스가 다방향으로 관통하도록 다수의 공극을 형성한 다공극성 티타늄 또는 알루미늄 금속 구조체를 파우더 또는 허니컴 형태가 아닌 금속 입체 구조물로 제조하고, 상기 다공극성 금속 구조체 상에 고비표면적을 가지는 세라믹(티타니아 또는 알루미나) 나노튜브를 성장시켜 상기 세라믹 나노튜브 내부 및 외부 표면에 소량의 활성금속을 나노박막층으로 고분산 증착 또는 담지시킴으로써, 생산성 및 경제성이 우수할 뿐만 아니라 촉매 성능이 우수한 고효율의 선박용 탈질 촉매에 관한 것이다. 또한, 본 발명에 따른 선박용 탈질 촉매는 탈질 시스템의 구조에 따라 상기 다공극성 금속 구조체의 형상을 원형, 사각형 등 다양한 형태로 변화시킬 수 있으므로, 선박 내 한정된 공간에서 최소화 및 최적화하여 설치할 수 있을 뿐만 아니라 설치가 용이하고 유지보수 및 관리가 편리하다.
摘要:
Disclosed is a method of oxidizing a substrate comprising contacting the substrate, an oxidant, and a solid phase comprising a plurality of pendant groups having affinity for a substrate to be oxidised and an oxidation catalyst. Also disclosed is a solid phase and membrane for use in the method. Also disclosed is a method for preparing the solid phase, and system for oxidizing a substrate.
摘要:
본 발명은 1차 공침 및 2차 공침하는 단계를 포함하는 다성분계 비스무스-몰리브덴 복합금속산화물 촉매의 제조방법, 이로부터 제조된 다성분계 비스무스-몰리브덴 복합금속산화물 촉매에 관한 것이다. 이에 따른, 상기 제조방법은 상기 촉매를 구성하는 금속 성분을 1차 및 2차 공침으로 2단계 나누어 공침시킴으로써 종래의 4성분계 비스무스-몰리브덴 촉매와 거의 동일한 구조를 가질 수 있어 촉매 구조 변형에 의한 촉매 활성 저하가 억제될 수 있으며, 반응 중에 소모되는 격자산소의 수를 조절할 수 있어 촉매 활성을 높여 상기 촉매를 이용한 촉매 반응 공정, 특히 상대적으로 저온조건에서의 촉매 반응 공정에서 부산물의 생성은 줄이고 반응물의 전환율 및 목적 생성물의 수율은 향상되는 효과가 있다.