摘要:
A process for the catalytic reduction of NO.sub.x, the reduction taking place in the presence of a catalyst which comprises(a) from 20 to 97 wt % of A.sub.2 O.sub.3,(b) from 1 to 40 wt % of CuO,(c) from 1 to 50 wt % of ZnO,(d) from 1 to 40 wt % of Ag,(e) from 0 to 2 wt % of Pt,(f) from 0 to 20 wt % of oxides of rare earth metals, elements of the 3rd subgroup of the Periodic Table of the Elements or mixtures thereof,based on the total weight of the components (a) to (e), which adds up to 100 wt %, wherein, in each case, up to half the weight of the component (a) may be replaced by Fe.sub.2 O.sub.3, Cr.sub.2 O.sub.3, Ga.sub.2 O.sub.3 or mixtures thereof, of the component (b) by CoO, of the component (c) by MgO, of the component (d) by Au and of the component (e) by Pd, Ru, Os, Ir, Rh, Re or mixtures thereof, is used for reducing NO.sub.x, especially in combustion off-gases, the components (a), (b) and (c) forming a spinel which is doped with the components (d), (e) and (f).
摘要:
A storage catalyst includes (1) a component that has a catalytic reducing action for nitrogen oxides at least in the presence of hydrocarbons, and (2) a component that stores NOx at least at temperatures of below 100° C. The catalytically active component is of the general chemical formula AaBbO4, where A is one or more divalent metals and B is one or more trivalent metals, and where a+b≦3 and a, b>0. The reaction enthalpy or the chemical activity between the catalytically active component and the NOx-storing component is low at least up to temperatures of 600° C.
摘要翻译:存储催化剂包括(1)至少在烃存在下对氮氧化物具有催化还原作用的组分,和(2)至少在低于100℃的温度下存储NOx的组分。催化活性组分是 的一般化学式AaBbO4,其中A是一种或多种二价金属,B是一种或多种三价金属,并且其中a + b <= 3和a,b> 0。 催化活性组分和NOx储存组分之间的反应焓或化学活性至少高达600℃的温度。
摘要:
The invention relates to a method and a device for cleaning flowing gases. To reduce the total emissions, nitrogen oxides, especially NO and NOx, are extracted at least partially from the gas to be scrubbed, in the temperature range from 50 and 300° C., preferably between 50 and 150° C. To extract the nitrogen oxides, an intermediate storage medium is used that is composed of a storage material and a supporting material for the storage material. The intermediate storage medium having in particular a composition of the formal chemical formula Ag.CuAl2O4 in an Al2O3 matrix, with the composition being a spinel or being of the spinel type, and with the composition having characteristic spinel lines in the x-ray spectrum, where 0≦x
摘要翻译:本发明涉及清洗流动气体的方法和装置。 为了减少总排放量,氮氧化物,尤其是NO和NO x至少部分地从待洗涤的气体中提取,温度范围为50-300℃,优选为50-150℃。为了提取氮 氧化物,使用由储存材料和用于储存材料的支撑材料组成的中间储存介质。 中间储存介质特别是在Al 2 O 3基质中具有形式化学式Ag.CuAl 2 O 4的组成,其组成为尖晶石或尖晶石型,并且组合物在x射线谱中具有特征尖晶石线, 其中0 <= X <1。
摘要:
A catalyst and a process for producing the catalyst are provided. For the catalytic reduction of NO.sub.x and for the oxidation of hydrocarbons, the catalyst contains a spinel containing the metals copper, zinc and aluminum.
摘要:
An exhaust gas purification device includes a porous body of catalytic material of the general formula AaBbO4 disposed in an exhaust gas stream of an engine. The porous body of catalytic material has a characteristic response temperature above which it is catalytically active to reduce pollutants in the presence of a reducing agent. The porous body stores at least 20% by volume hydrocarbons at temperatures below the response temperature. A represent at least one element selected from Mg, Ca, Mn, Fe, Ni, Co, Cu, Zn, Sn, Ti and A+B is less than 3, A is greater than 0 and B greater than 0.
摘要:
The invention relates to a method and a device for cleaning flowing gases. To reduce the total emissions, nitrogen oxides, especially NO and NOx, are extracted at least partially from the gas to be scrubbed, in the temperature range from 50 and 300.degree. C., preferably between 50 and 150.degree. C. To extract the nitrogen oxides, an intermediate storage medium is used that is composed of a storage material and a supporting material for the storage material. The intermediate storage medium having in particular a composition of the formal chemical formula Ag.CuAl.sub.2 O.sub.4 in an Al.sub.2 O.sub.3 matrix, with the composition being a spinel or being of the spinel type, and with the composition having characteristic spinel lines in the x-ray spectrum, where 0.ltoreq.x
摘要翻译:本发明涉及清洗流动气体的方法和装置。 为了减少总排放量,氮氧化物,特别是NO和NOx,至少部分地从待洗涤的气体中提取,温度范围为50-300℃,优选为50-150℃。为了提取氮 氧化物,使用由储存材料和用于储存材料的支撑材料组成的中间储存介质。 中间储存介质特别是在Al 2 O 3基质中具有形式化学式Ag.CuAl 2 O 4的组成,其组成为尖晶石或尖晶石型,并且组合物在x射线谱中具有特征尖晶石线, 其中0 = x <1。
摘要:
The present invention is directed to a purification device that includes a porous body and a catalyst. To reduce the emission of pollutants, a pollutant-containing stream of gas flows through the porous body.
摘要:
A catalyst and a process for producing the catalyst are provided. For the catalytic reduction of NO.sub.x and for the oxidation of hydrocarbons, the catalyst contains a spinel containing the metals copper, zinc and aluminum.
摘要:
A catalyst and a method for producing the catalyst, for catalytic reduction of NO.sub.x and oxidation of hydrocarbons, the catalyst comprises a zinc, copper and aluminum spinel to which, at least one element selected from palladium, platinum, rhodium, ruthenium, osmium, iridium, rhenium and/or rare earth metals, such as lanthanum and cerium, vanadium, titanium, niobium, molybdenum, tungsten and/or salts thereof and/or oxides thereof has been added.
摘要:
NO.sub.x, where x is 1 and 2, in exhaust gases is reduced over heterogeneous catalysts with hydrocarbons, carbon monoxide, hydrogen or mixtures thereof in the presence of oxygen from 100 to 650.degree. C. and an absolute pressure of from 0.5 to 50 bar by a process in which the heterogeneous catalysts used are bimodal or polymodal compounds of the general formula IA.sub.1-x M.sub.2 O.sub.4 (I),which, if required, are doped with rare earth metals, noble metal, titanium, vanadium, molybdenum, tungsten or mixtures thereof, and whereA is magnesium, calcium, titanium, vanadium, chromium, manganese, iron, cobalt, nickel, copper, zinc, tin or mixtures thereof,M is aluminum, gallium, indium, tin, chromium, manganese, iron, cobalt, nickel, copper, zinc or mixtures thereof andx is from 0 to 0.99,whose oxygen atoms are in a cubic close packed arrangement and A is present in the tetrahedral sites and M in the octahedral sites, it also being possible for A to occupy octahedral sites if an equivalent amount of M occupies tetrahedral sites.