摘要:
A diesel exhaust gas system includes a diesel particulate filter (DPF), a trap for nitrogen oxides (LNT), a hydrocarbon catalytic reformer for generating reformate, and an air supply. A method for controlling the rate of burn of soot in a DPF limits the oxygen percentage in the exhaust to about 6%. The LNT may be located ahead of the DPF in the exhaust line. Reformate is directed with exhaust through the LNT. The second flow of air cools the exhaust gas and thereby prevents overheating of the DPF substrate. The DPF also may be located ahead of the LNT. Reformate is controllably combusted by the second air flow in the DPF, reducing the oxygen percentage to about 6%, thus limiting the rate at which soot in the DPF can burn and thereby preventing overheating of the DPF substrate.
摘要:
A NOx abatement system comprising: a first NOx adsorber (18) capable of being disposed in-line and downstream of and in fluid communication with an engine (12); a selective catalytic reduction catalyst (20) disposed in-line and downstream of and in direct fluid communication with the first NOx adsorber (18), wherein the selective catalytic reduction catalyst (20) is capable of storing ammonia; and an off-line reformer (24) disposed in selective communication with and upstream of the first NOx adsorber (18) and the selective catalytic reduction catalyst (20), wherein the reformer (24) is capable of producing a reformate comprising primarily hydrogen and carbon monoxide.
摘要:
An exhaust emission control system can include a reformer a fuel source disposed upstream of and in fluid communication with the reformer, and a NOx adsorber disposed downstream of and in fluid communication with the reformer. The NOx adsorber can include a NOx adsorber catalyst having an acid adsorber disposed on the substrate and a base adsorber disposed over the acid adsorber.
摘要:
In one embodiment, a method of reducing NOx contaminant in an exhaust stream includes: introducing diesel fuel and an oxidant to a reformer to produce a reformer effluent comprising hydrogen and nitrogen, introducing the reformer effluent to a non-thermal plasma reactor to produce ammonia, and introducing an exhaust stream and the ammonia to a SCR catalyst, whereby the NOx contaminant reacts with the ammonia.
摘要:
In one embodiment, an exhaust treatment system comprises a selective catalytic reduction device, an off-line reformer disposed in selective fluid communication with and upstream of the selective catalytic reduction device, and a plasma reactor disposed downstream of and in fluid communication with the off-line reformer, and disposed upstream of and in fluid communication with the selective catalytic reduction device. The selective catalytic reduction device is capable of storing ammonia and of enabling the reaction of the ammonia with NOx. The reformer is capable of producing a reformate comprising hydrogen and nitrogen. The plasma reactor is capable of producing ammonia from the reformate, and is a thermal plasma reactor or a surface discharge non-thermal plasma reactor.
摘要:
In one embodiment, an exhaust treatment device includes: a substrate, a shell disposed around the substrate, and a retention material disposed between the shell and the substrate. The substrate includes a catalyst that includes a precious metal and a solid solution comprising solid solution metals, wherein the solid solution metals include yttrium, zirconium, and titanium.
摘要:
An exhaust treatment device comprises a shell; a substrate disposed within the shell, the substrate having a catalyst disposed thereon, wherein the catalyst comprises platinum and a protective layer selected from the group consisting of tin oxide, iron oxide, and manganese oxide, and wherein the catalyst is capable of oxidizing greater than or equal to 50 wt. % carbon monoxide present in an exhaust gas stream at temperatures of about 150° C. to about 200° C.
摘要:
One embodiment of an ammonia gas sensor includes: a reference electrode, an ammonia selective sensing electrode and an electrolyte disposed therebetween. The sensing electrode comprises the reaction product of a main material selected from the group consisting of vanadium, tungsten, molybdenum, vanadium oxides, tungsten oxides, molybdenum oxides, and combinations comprising at least one of the foregoing main materials, and an electrically conducting material selected from the group consisting of electrically conductive metals, electrically conductive metal oxides, and combinations comprising at least one of the foregoing.
摘要:
Disclosed herein are NOx sensors and methods of using the same. In one embodiment, a method for sensing NOx comprises: contacting a first NOx electrode with the gas, contacting a second NOx electrode with the gas, determining a NO2 emf between the first NOX electrode and a first reference electrode, determining a NOx emf between the second NOx electrode and a second reference electrode, and determining a NO2 concentration and a NO concentration using the NO2 emf and the NOx emf. The first electrode can be at a first temperature of greater than or equal to about 700° C., and the second electrode can be at a second temperature of about 500° C. to about 650° C.
摘要:
A method for preparing a non-thermal plasma reactor substrate includes disposing electrical vias on green stage first and second ceramic plates; filling the electrical vias with conductive material; and forming electrical contact via cover pads; disposing conductive material on the first ceramic plate to form an electrode plate having a main electrode portion and a terminal lead for electrically connecting the main electrode portion to the electrical vias; laminating the electrode plate and the second ceramic plate together, embedding the electrode therebetween; co-firing the plates to form a laminated co-fired embedded-conductor element; stacking a plurality of the laminated co-fired embedded-conductor elements to form a multi-cell stack, the filled electrical vias aligning in the stack to provide an electrical bus for connecting alternating elements in the stack; and disposing spacers with matching vias and via cover pads between adjacent pairs of elements to form exhaust gas passages.