Abstract: A catalyst made by the introduction of copper ions and cobalt ions into a Y-type zeolite to produce a CuCoY zeolite improves the reduction of NOx in exhaust from a lean burn engine, such as a diesel engine. A dual bed selective reduction reactor in the exhaust stream comprising a first bed of BaY or of Ag/alumina and a second bed of CuCoY is particularly effective in reduction of NOx. In one embodiment, the exhaust stream is suitably treated with an oxidant, such as ozone, and a reductant, such as a diesel hydrocarbon or oxygenated diesel hydrocarbon, before the exhaust passes in contact with the dual bed catalyst.

Abstract: A catalyst made by the introduction of copper ions and cobalt ions into a Y-type zeolite to produce a CuCoY zeolite improves the reduction of NOx in exhaust from a lean burn engine, such as a diesel engine. A dual bed selective reduction reactor in the exhaust stream comprising a first bed of BaY or of Ag/alumina and a second bed of CuCoY is particularly effective in reduction of NOx. In one embodiment, the exhaust stream is suitably treated with an oxidant, such as ozone, and a reductant, such as a diesel hydrocarbon or oxygenated diesel hydrocarbon, before the exhaust passes in contact with the dual bed catalyst.

Abstract: A method for reducing nitrogen oxides including NO and NO2 in an exhaust stream also comprising oxygen, carbon monoxide and hydrocarbons at a temperature above about 150° C., the method including in embodiments oxidizing NO in the exhaust stream to NO2; reforming raw diesel fuel to produce OHC's from the fuel; adding diesel fuel hydrocarbons and their oxygenates to the exhaust stream for the reduction of nitrogen oxides; and contacting the exhaust stream with a reduction hybrid catalyst comprising BaY—Ag/Al2O3 to reduce the nitrogen oxides to N2. The method reduces NOx initially through the (HC+OHC)/SCR process producing N2, while also producing NH3 as a byproduct over Ag/Al2O3. The NH3 subsequently reduces NOx over the BaY—Ag/Al2O3 hybrid catalyst through the NH3/SCR process, producing more N2 and thereby enhancing the NOx reduction efficiency of the hybrid catalyst system.

Abstract: A catalyst made by the introduction of copper ions and cobalt ions into a Y-type zeolite to produce a CuCoY zeolite improves the reduction of NOx in exhaust from a lean bum engine, such as a diesel engine. A dual bed selective reduction reactor in the exhaust stream comprising a first bed of BaY or of Ag/alumina and a second bed of CuCoY is particularly effective in reduction of NOx. In one embodiment, the exhaust stream is suitably treated with an oxidant, such as ozone, and a reductant, such as a diesel hydrocarbon or oxygenated diesel hydrocarbon, before the exhaust passes in contact with the dual bed catalyst.

Abstract: Raw diesel fuel is reformed to produce partially oxygenated hydrocarbons in the liquid fuel by use of a nonthermal plasma reactor. The reformed diesel fuel is formed by passing a stream of air plasma bubbles through a liquid volume of diesel fuel to strip low molecular weight hydrocarbons from the fuel, while partially oxygenating an abundance of them as a reformate for addition to the exhaust. This reformed diesel fuel is introduced as a sidestream into the exhaust of a diesel engine or other lean-burn power plants as reactants for selective catalytic reduction of nitrogen oxides in the exhaust. Fresh fuel is added to the liquid volume as diesel reformate is stripped from it, and a portion of the stripped fuel is withdrawn from the liquid volume.

Abstract: A method for reducing nitrogen oxides including NO and NO2 in an exhaust stream also comprising oxygen, carbon monoxide and hydrocarbons at a temperature above about 150° C., the method including in embodiments oxidizing NO in the exhaust stream to NO2; reforming raw diesel fuel to produce OHC's from the fuel; adding diesel fuel hydrocarbons and their oxygenates to the exhaust stream for the reduction of nitrogen oxides; and contacting the exhaust stream with a reduction hybrid catalyst comprising BaY—Ag/Al2O3 to reduce the nitrogen oxides to N2. The method reduces NOx initially through the (HC+OHC)/SCR process producing N2, while also producing NH3 as a byproduct over Ag/Al2O3. The NH3 subsequently reduces NOx over the BaY-Ag/Al2O3 hybrid catalyst through the NH3/SCR process, producing more N2 and thereby enhancing the NOx reduction efficiency of the hybrid catalyst system.

Abstract: Ozone, preferably produced in an ambient air stream passed through a non-thermal hyperplasma reactor, is added to the hot exhaust gas stream from a lean-burn (oxygen-rich) combustion source. The ozone converts much of the NO in the NOx containing exhaust stream to NO2. The resulting NO2/NOx ratio can be controlled by the input energy density to the plasma reactor. Ammonia and/or urea is added to the ozone treated exhaust in proportion to the NOx content, and the stream passed into contact with a reduction catalyst, such as a base metal-exchanged zeolite, to convert the NOx to nitrogen.

Abstract: The nitric oxide (NO) and nitrogen dioxide (NO2) content of lean-burn engine exhaust is beneficially prepared for selective catalytic reduction (SCR) of these oxides to nitrogen by two sidestream additions to the exhaust. An ozone-containing air stream is added to the exhaust to affect oxidation of NO to NO2. And a hydrocarbon(s) fuel constituent is added to a second humidified ozone-containing air stream and that mixture subjected to UV radiation. Strongly oxidizing hydroxyl radicals are formed by interaction of ozone, water, and UV radiation for reaction with the hydrocarbon. The resulting partially oxidized hydrocarbons (Pox) are added to the exhaust, providing effective reduction materials for the SCR of NO2 to nitrogen and water.

Abstract: The selective catalytic reduction of nitrogen oxides (especially NO and NO2) in exhaust from diesel and other lean burn engines is improved by use of a compact hyperplasma reactor for generating ozone and other highly oxidizing species in a stream of air. A portion of the ozone containing air stream is blown directly into the exhaust for oxidizing NO to NO2. The other portion of plasma treated air is used to fractionate and reform a volume of diesel fuel to produce low molecular weight hydrocarbons and oxidized hydrocarbons to be added to the exhaust as NO2 reductants in the catalytic reduction.

Abstract: A plasma reactor for automotive exhaust gas applications which efficiently promotes diffusion, mass transfer and chemical reaction processes of atoms, ions and radicals, in that the ground (outer) electrode has an axially discrete pattern which provides alternating regions of active and passive electric field along the axial direction of the plasma reactor. As the exhaust gas passes axially along the plasma reactor, each active region produces plasma atoms, ions and radicals, which then have time to react with the NOx over the course of the adjacent passive region. In this manner, successive active regions produce copious atoms, radicals and ions, and the adjacent passive regions provide time for these radicals and ions to react with the NOx and hydrocarbons before the next active region is encountered by the moving stream of exhaust gas, thereby enhancing the performance of the plasma reactor.

Abstract: The invention includes an operating strategy for zeolite-based catalysts used for reduction of NO.sub.x from highly lean exhaust conditions. The invention includes a method to enhance the high temperature activity of zeolite-based catalysts by modifying the transient feed composition without changing the overall time-average feed composition. More specifically, a cyclic operation method with alternating feed conditions between rich and lean to enhance the activity of zeolite-based catalysts to remove NO from lean exhaust gases when the overall exhaust composition contains a large amount of excess oxygen, without affecting the catalyst's activity to remove hydrocarbons. The rich to lean transient conditions are created by periodically adding hydrocarbon pulses from a different source to the combustion emissions.

Abstract: This invention relates to an automotive exhaust gas treatment catalyst composed of one or more noble metals dispersed on CeO.sub.2 -RE.sub.2 O.sub.3 carrier particles. The ceria-rare earth oxide carrier for the noble metal facilitates the simultaneous oxidation of CO and decomposition of NO. The catalyst is particularly useful when the air-fuel mixture to the automobile engine is continually cycled between fuel rich and fuel lean of stoichiometric proportions.

Abstract: An automobile catalytic converter of extruded ceramic monolithic honeycomb structure for treatment of automotive exhaust gas. The monolithic structure contains longitudinally extended channels formed of thin walls in a periodic pattern of cross sections of different areas to induce different flow velocities of the exhaust gas in the immediate adjacent channels. Temperature gradients thereby produced between the adjacent channels promote heat transfer in the transverse direction of the honeycomb structure to prevent the formation of maximum temperature in each channel at the same longitudinal location of the channel wall.