Abstract: Methods and systems for selective catalytic reduction of NOx with an ammonia reductant and a zeolite catalyst loaded with at least two metals selected from the group of tungsten, cobalt, and vanadium. An exhaust stream including NOx and a reductant stream including ammonia are provided to a catalytic reactor having the metal loaded zeolite catalyst at suitable operating temperatures for NOx reduction of at least 90%.

Abstract: Methods and systems for selective catalytic reduction of NOx with an activated-carbon-supported metal catalyst at an operating temperature of between about between about 500° C. and about 750° C. An exhaust stream including NOx is introduced to a catalytic reactor having the activated-carbon-supported metal catalyst for NOx reduction of at least 90%. A second catalyst reactor can be provided downstream to remove or convert nitrous oxide as desired.

Abstract: Methods and systems are provided for selective catalytic reduction of NOx with a low molecular low molecular weight hydrocarbon, e.g., propylene, as a reductant using a catalyst system including two catalysts. An exhaust stream containing an amount of NOx from a combustion operation is provided. A portion of the exhaust stream and a reductant stream including a low molecular weight hydrocarbon is introduced to a first catalytic reactor, which comprises a first catalyst including alumina loaded with silver. The NOx-reduced exhaust stream from the first catalyst is then directed to a second catalyst including zirconia loaded with at least one metal.

Abstract: Methods and systems are provided for selective catalytic reduction of NOx with a low molecular low molecular weight aldehyde, e.g., acetaldehyde, as a reductant using a catalyst system including two catalysts. An exhaust stream containing an amount of NO from a combustion operation is provided. A portion of the exhaust stream is introduced to a first catalyst to convert the NO to NO2. The exhaust stream from the first catalyst with NO2 and a reductant stream containing a low molecular weight aldehyde, e.g., acetaldehyde, are introduced to the second catalyst to convert the NO2 to N2. The first catalyst can be bulk Co3O4, Ru or Pt loaded on alumina; the second catalyst can be various zeolites, or zeolites loaded with potassium.

Abstract: Methods and systems for selective catalytic reduction of NOx with an ammonia reductant and a zeolite catalyst loaded with at least two metals selected from the group of tungsten, cobalt, and vanadium. An exhaust stream including NOx and a reductant stream including ammonia are provided to a catalytic reactor having the metal loaded zeolite catalyst at suitable operating temperatures for NOx reduction of at least 90%.

Abstract: Methods and systems are provided for selective catalytic reduction of NOx with a low molecular low molecular weight aldehyde, e.g., acetaldehyde, as a reductant using a catalyst system including two catalysts. An exhaust stream containing an amount of NO from a combustion operation is provided. A portion of the exhaust stream is introduced to a first catalyst to convert the NO to NO2. The exhaust stream from the first catalyst with NO2 and a reductant stream containing a low molecular weight aldehyde, e.g., acetaldehyde, are introduced to the second catalyst to convert the NO2 to N2. The first catalyst can be bulk Co3O4, Ru or Pt loaded on alumina; the second catalyst can be various zeolites, or zeolites loaded with potassium.

Abstract: Methods and systems are provided for selective catalytic reduction of NOx with a low molecular low molecular weight hydrocarbon, e.g., propylene, as a reductant using a catalyst system including two catalysts. An exhaust stream containing an amount of NOx from a combustion operation is provided. A portion of the exhaust stream and a reductant stream including a low molecular weight hydrocarbon is introduced to a first catalytic reactor, which comprises a first catalyst including alumina loaded with silver. The NOx-reduced exhaust stream from the first catalyst is then directed to a second catalyst including zirconia loaded with at least one metal.

Abstract: Methods and systems for selective catalytic reduction of NOx with an activated-carbon-supported metal catalyst at an operating temperature of between about between about 500° C. and about 750° C. An exhaust stream including NOx is introduced to a catalytic reactor having the activated-carbon-supported metal catalyst for NOx reduction of at least 90%. A second catalyst reactor can be provided downstream to remove or convert nitrous oxide as desired.

Abstract: The present invention is a method for operating a rapid cycling pressure swing adsorption (RCPSA) having a cycle time, T, to separate a feed gas into a non-adsorbed gas and tail gas. The method includes the steps of passing the feed gas having a purity of F % at high pressure into a first end of a bed which selectively adsorbs the tail gas and passes the product gas out a second end of the bed for a time, F. The product gas has a purity, P %, and a rate of recovery of R %. Then the bed is cocurrently depressurized for a time, tCO, followed by countercurrently depressurizing the bed for a time, tCN. The bed is then purged for a time, tP, wherein desorbate (tail gas) is released at the first end of the bed at a pressure greater than 30 psig, Subsequently the bed is repressurized for a duration, tRP. R>80%, P/F?1.1 or R?90%, 0<P/F <1.1.

Abstract: Improved hydroprocessing processes for upgrading refinery streams via the use of rapid cycle pressure swing absorption having a cycle time of less than 30 s for increasing the concentration of hydrogen in the vapor phase product recycled to the hydroprocessing zone.