摘要:
To provide a method for controlling a NOx reduction system which can remove NOx with a satisfactorily high efficiency even under low-temperature operating conditions as in diesel cars. The NOx reduction system comprises NOx treatment means disposed in an exhaust passage in an internal combustion engine, and air-fuel ratio control means for bringing the air-fuel ratio of an exhaust gas to a lean or rich state. The NOx treatment means comprises at least a first catalyst layer containing a solid acid catalyst capable of adsorbing ammonia and a second catalyst layer containing a noble metal and a cerium oxide material. The second catalyst layer and the first catalyst layer are stacked in that order on a carrier, and the first catalyst layer constitutes the uppermost layer. The air-fuel ratio control means controls so that the lean state and the rich state are repeated at predetermined intervals. According to the above constitution, NOx is passed through the first catalyst layer in the lean state and is temporarily stored in the second catalyst layer. Thereafter, in the rich state, NOx is converted to NH3 and is restored in the first catalyst layer. When the state is again returned to the lean state, NH3 is converted to nitrogen which is finally released from the first catalyst layer.
摘要:
A NOx reduction system comprises NOx treatment catalyst and air-fuel ratio control switch for changing the air-fuel ratio of an exhaust gas to a lean or rich state. The NOx treatment catalyst comprises at least a first catalyst layer containing a solid acid catalyst capable of adsorbing ammonia and a second catalyst layer containing a noble metal and a cerium oxide material. The second and the first catalyst layer are stacked in that order on a carrier, and the first catalyst layer constitutes the uppermost layer. NOx is passed through the first catalyst layer in the lean state and is temporarily stored in the second catalyst layer. Thereafter, in the rich state, NOx is converted to NH3 and is restored in the first catalyst layer. When the state is again returned to the lean state, NH3 is converted to nitrogen which is finally released from the first catalyst layer.
摘要:
The present invention provides an NOx purifying catalyst that removes NOx with sufficient efficiency even under low temperature operation such as diesel engine automobiles. An NOx purifying catalyst for processing NOx in exhaust gas by rich/lean control of the air-fuel ratio of the exhaust gas, includes a first catalytic layer containing β-zeolite having iron and/or cerium elements, and a second catalytic layer including a noble metal and cerium oxide-based material; in which the second and the first catalytic layers are coated on a support in that order so that the first catalytic layer is the uppermost layer. The NOx purifying catalyst purifies NOx as showed in Reaction Formulations (1) to (4). Lean condition 1: NO+½O2→NO2 (1) Rich condition: CO+H2O→CO2 (2) NOx+H2→NH3 (3) Lean condition 2: NOx+NH3+O2→N2+H2O (4).
摘要:
The present invention provides an NOx purifying catalyst that removes NOx with sufficient efficiency even under low temperature operation such as diesel engine automobiles. An NOx purifying catalyst for processing NOx in exhaust gas by rich/lean control of the air-fuel ratio of the exhaust gas, includes a first catalytic layer containing β-zeolite having iron and/or cerium elements, and a second catalytic layer including a noble metal and cerium oxide-based material; in which the second and the first catalytic layers are coated on a support in that order so that the first catalytic layer is the uppermost layer. The NOx purifying catalyst purifies NOx as showed in Reaction Formulations (1) to (4). Lean condition 1: NO+½O2−>NO2 (1) Rich condition: CO+H2O−>CO2 (2) NOx+H2−>NH3 (3) Lean condition 2: NOx+NH3+O2−>N2+H2O (4)
摘要翻译:本发明提供一种NOx净化催化剂,即使在诸如柴油机汽车的低温操作下也能以足够的效率除去NOx。 用于通过对废气的空燃比进行浓缩/稀疏控制来处理废气中的NOx的NOx净化催化剂包括含有具有铁和/或铈元素的β-沸石的第一催化剂层和包含 贵金属和氧化铈基材料; 其中第二催化剂层和第一催化剂层依次涂覆在载体上,使得第一催化剂层是最上层。 NOx净化催化剂如反应制剂(1)至(4)所示净化NOx。 <?in-line-formula description =“在线公式”end =“lead”?>精益条件1:NO + 1/2> 2 SUB> )<?in-line-formula description =“In-line Formulas”end =“tail”?> <?in-line-formula description =“In-line Formulas”end =“lead”?> Rich condition:CO + (2)<βin-line-formula description =“In-line Formulas”end =“tail”?> <?in- line-formula description =“In-line Formulas”end =“lead”?> NO sub> 2 H 3 )<?in-line-formula description =“In-line Formulas”end =“tail”?> <?in-line-formula description =“In-line Formulas”end =“lead”?> Lean condition 2:NO N + 2 + N 2 + H 2 O 2 + N 2 + H 2 O 2 (4)<?in-line-formula description =“In-line Formulas”end =“tail”?>
摘要:
Disclosed is a NOx purifying catalyst which is capable of removing NOx sufficiently efficiently even during operations at low temperatures such as operations in diesel cars. Specifically disclosed is a NOx purifying catalyst for processing NOx in an exhaust gas by performing lean/rich control of air-fuel ratio of the exhaust gas. This NOx purifying catalyst comprises at least a first catalyst layer containing a β zeolite containing iron element and a second catalyst layer containing a noble metal, a cerium oxide material and a specific zirconium oxide material. The second catalyst layer and the first catalyst layer are sequentially arranged on a carrier in such a manner that the first catalyst layer forms the uppermost layer.
摘要:
Disclosed is a NOx purifying catalyst which is capable of removing NOx sufficiently efficiently even during operations at low temperatures such as operations in diesel cars. Specifically disclosed is a NOx purifying catalyst for processing NOx in an exhaust gas by performing lean/rich control of air-fuel ratio of the exhaust gas. This NOx purifying catalyst comprises at least a first catalyst layer containing a β zeolite containing iron element and a second catalyst layer containing a noble metal, a cerium oxide material and a specific zirconium oxide material. The second catalyst layer and the first catalyst layer are sequentially arranged on a carrier in such a manner that the first catalyst layer forms the uppermost layer.
摘要:
Disclosed is a NOx purifying catalyst which is capable of removing NOx sufficiently efficiently even during operations at low temperatures such as operations in diesel cars. Specifically disclosed is a NOx purifying catalyst for processing NOx in an exhaust gas by performing lean/rich control of air/fuel ratio of the exhaust gas. This NOx purifying catalyst comprises at least a first catalyst layer containing a β zeolite containing iron element and a cerium oxide material and a second catalyst layer containing a noble metal, a cerium oxide material and a heat-resistant inorganic oxide. The second catalyst layer and the first catalyst layer are sequentially arranged on a carrier in such a manner that the first catalyst layer forms the uppermost layer.
摘要:
Disclosed is a NOx purifying catalyst which is capable of removing NOx sufficiently efficiently even during operations at low temperatures such as operations in diesel cars. Specifically disclosed is a NOx purifying catalyst for processing NOx in an exhaust gas by performing lean/rich control of air/fuel ratio of the exhaust gas. This NOx purifying catalyst comprises at least a first catalyst layer containing a β zeolite containing iron element and a cerium oxide material and a second catalyst layer containing a noble metal, a cerium oxide material and a heat-resistant inorganic oxide. The second catalyst layer and the first catalyst layer are sequentially arranged on a carrier in such a manner that the first catalyst layer forms the uppermost layer.
摘要:
An approaching vehicle detecting system that detects an approaching vehicle on the basis of sounds collected by a plurality of sound collectors mounted on a host vehicle determines whether a transverse moving direction of a sound source detected by the plurality of sound collectors is a direction approaching the host vehicle, determines whether a vertical position of the sound source detected using the plurality of sound collectors is in the same plane as that of the host vehicle, and detects that sound source as the approaching vehicle when it is determined that the transverse moving direction of the sound source is the direction approaching the host vehicle and the vertical position of the sound source is in the same plane as that of the host vehicle.
摘要:
A sound source detection system for detecting a sound source (e.g., running sound of a vehicle) based on sound collected by microphones extracts characteristic amounts from the sound collected by the microphones, sets a plurality of classes according to the position of the sound source by a multi-class pattern recognition method (e.g., multi-class SVM) using the characteristic amounts, extracts characteristic amounts from sound collected by the microphones for detection of a sound source, determines a class to which the extracted characteristic amounts belong, from the preset plurality of classes, and estimates the sound source based on the class.