Abstract: Disclosed are processes for removing H2S from gas streams containing H2S, the processes comprise contacting gas streams with a mixed metal oxy-hydroxide media comprising two or more metals selected from the group consisting of magnesium, chromium, manganese, iron, cobalt, zinc and copper. Also disclosed are processes for removing H2S from gas streams containing H2S, the processes comprise contacting the gas streams with a mixed metal oxy-hydroxide media comprising one or more metals selected from the group listed above plus one or more metals selected from the group consisting of aluminum, silicon, titanium and zirconium.

Abstract: A filtration device including a fluid-impermeable housing having a gas inlet and outlet, and containing within the housing first filter media particles of an extended surface area substrate and containing at least one metal impregnant, and second filter media particles of an extended surface area zirconium hydroxide substrate and containing zinc (hydr)oxide. The first or second filter media particles also contain an amine-functional material. The device may be used in atmospheres containing various harmful gases, and may provide particularly useful improvements in breakthrough times for nitrogen dioxide, hydrogen sulfide, ammonia and formaldehyde compared to a device containing only the first filter media particles or only the second filter media particles.

Abstract: A filtration device including a fluid-impermeable housing having a gas inlet and outlet, and containing within the housing first filter media particles of an extended surface area substrate and containing at least one metal impregnant, and second filter media particles of an extended surface area zirconium hydroxide substrate and containing zinc (hydr)oxide. The first or second filter media particles also contain an amine-functional material. The device may be used in atmospheres containing various harmful gases, and may provide particularly useful improvements in breakthrough times for nitrogen dioxide, hydrogen sulfide, ammonia and formaldehyde compared to a device containing only the first filter media particles or only the second filter media particles.

Abstract: A method for extending the service life of a Collective Protection (CP) filter includes: providing at least one CP filter comprising a filter bed; and passing an airstream through a supplemental bed configured to enhance the filter bed by promoting reactions that facilitate the removal of one or more of chemical warfare agents and toxic threat compounds. An apparatus for extending the service life of a Collective Protection (CP) filter, the apparatus including: a CP filter comprising a filter bed; and a supplemental bed configured so as to enhance the filter bed by promoting reactions that facilitate the removal of chemical warfare agents and toxic chemicals.

Abstract: A composite filtration media for removing broad spectrum toxic chemicals from streams of air comprised of a physical mixture of a zirconium hydroxide analog material and a basic gas removal material is taught in which the composite filtration media is prepared by blending the zirconium hydroxide analog material in powder form with the basic gas removal material in powder form before pressing into pellets, tablets, briquettes, or the like. Subsequent grinding of the pressed material can be employed to produce a powder form of the composite filtration media. Cross-reaction of the composite components is reduced, thus prolonging the service life of the filtration media. Effectiveness in removing ammonia and sulfur dioxide are demonstrated for various compositions of the composite filtration media in both dry and humid conditions, including after aging for three weeks in humid conditions.

Abstract: A filtration device including a fluid-impermeable housing having a gas inlet and outlet, and containing within the housing first filter media particles of an extended surface area substrate and containing at least one metal impregnant, and second filter media particles of an extended surface area zirconium hydroxide substrate and zinc (hydr)oxide. The device may be used in atmospheres containing various harmful gases, and may provide particularly useful improvements in NOx breakthrough times compared to a device containing only the first filter media particles or only the second filter media particles.

Abstract: A filtration device including a fluid-impermeable housing having a gas inlet and outlet, and containing within the housing first filter media particles of an extended surface area substrate and containing at least one metal impregnant, and second filter media particles of an extended surface area zirconium hydroxide substrate. The device may be used in atmospheres containing various harmful gases, and may provide particularly useful improvements in NOx breakthrough times compared to a device containing only the first filter media particles or only the second filter media particles.

Abstract: A natural gas-containing stream such as biogas from landfills and sewage treatment plants is freed of siloxane contaminants by passing the biogas through a bed containing an adsorbent having a neutral surface, which adsorbs the siloxanes. When the bed of neutral adsorbent is filled to capacity, the adsorbent bed is heated to remove the siloxanes and regenerate the bed. The neutral adsorbent reduces disadvantageous reactions between the adsorbent and siloxane and other impurities in the natural gas-containing stream.

Abstract: A method for extending the service life of a Collective Protection (CP) filter includes: providing at least one CP filter comprising a filter bed; and passing an airstream through a guard bed configured to protect the filter bed by removing one or more of airborne contaminants and battlefield contaminants. An apparatus for extending the service life of a CP filter includes: a CP filter comprising a filter bed; and a guard bed configured to protect the filter bed by removing one or more of airborne contaminants and battlefield contaminants.

Abstract: A natural gas-containing stream such as biogas from landfills and sewage treatment plants is freed of siloxane contaminants by passing the biogas through a bed containing an adsorbent having a neutral surface, which adsorbs the siloxanes. When the bed of neutral adsorbent is filled to capacity, the adsorbent bed is heated to remove the siloxanes and regenerate the bed. The neutral adsorbent reduces disadvantageous reactions between the adsorbent and siloxane and other impurities in the natural gas-containing stream.

Abstract: The present invention relates to a novel filtration media and process for removing toxic materials from streams of air at ambient conditions using the novel filtration media. The filtration media is comprised of porous zirconium hydroxide onto which at least one reactive moiety is impregnated.

Abstract: A multi-stage selective catalytic reduction (SCR) unit (32) provides efficient reduction of NOx and other pollutants from about 50-550° C. in a power plant (19). Hydrogen (24) and ammonia (29) are variably supplied to the SCR unit depending on temperature. An upstream portion (34) of the SCR unit catalyzes NOx+NH3 reactions above about 200° C. A downstream portion (36) catalyzes NOx+H2 reactions below about 260° C., and catalyzes oxidation of NH3, CO, and VOCs with oxygen in the exhaust above about 200° C., efficiently removing NOx and other pollutants over a range of conditions with low slippage of NH3. An ammonia synthesis unit (28) may be connected to the SCR unit to provide NH3 as needed, avoiding transport and storage of ammonia or urea at the site. A carbonaceous gasification plant (18) on site may supply hydrogen and nitrogen to the ammonia synthesis unit, and hydrogen to the SCR unit.

Abstract: The present invention relates to a process for decontaminating surfaces contaminated with toxic agents. The process comprises contacting a contaminated surface with a sorbent comprised of zirconium hydroxide onto which at least one reactive moiety is optionally impregnated.

Abstract: A method for oxidizing an amount of CO in a CO-containing gas stream, e.g., a combustion stream from fuel combustion, is provided. The method comprises exposing the CO-containing gas stream to a catalytic coating at reaction conditions, including at least 8 vol. % O2 and a temperature of at least 600° C. At these reaction conditions, the method comprises generating gaseous intermediate oxidizing species at the catalytic coating for oxidation of the carbon monoxide within the CO-containing gas stream as a homogeneous reaction to improve CO removal efficiency.

Abstract: A process and system (18) for reducing NOx in a gas using hydrogen as a reducing agent is provided. The process comprises contacting the gas stream (29) with a catalyst system (38) comprising sulfated zirconia washcoat particles (41), palladium, a pre-sulfated zirconia binder (44), and a promoter (45) comprising at least one of titanium, zinc, or a mixture thereof. The presence of zinc or titanium increases the resistance of the catalyst system to a sulfur and water-containing gas stream.

Abstract: Improved processes for activating a catalyst system used for the reduction of nitrogen oxides are provided. In one embodiment, the catalyst system is activated by passing an activation gas stream having an amount of each of oxygen, water vapor, nitrogen oxides, and hydrogen over the catalyst system and increasing a temperature of the catalyst system to a temperature of at least 180° C. at a heating rate of from 1-20°/min. Use of activation processes described herein leads to a catalyst system with superior NOx reduction capabilities.

Abstract: A process for the catalytic reduction of nitrogen oxides (NOx) in a gas stream (29) in the presence of H2 is provided. The process comprises contacting the gas stream with a catalyst system (38) comprising zirconia-silica washcoat particles (41), a pre-sulfated zirconia binder (44), and a catalyst combination (40) comprising palladium and at least one of rhodium, ruthenium, or a mixture of ruthenium and rhodium.

Abstract: Improved processes for activating a catalyst system used for the reduction of nitrogen oxides are provided. In one embodiment, the catalyst system is activated by passing an activation gas stream having an amount of each of oxygen, water vapor, nitrogen oxides, and hydrogen over the catalyst system and increasing a temperature of the catalyst system to a temperature of at least 180° C. at a heating rate of from 1-20°/min. Use of activation processes described herein leads to a catalyst system with superior NOx reduction capabilities.

Abstract: A process for the catalytic reduction of nitrogen oxides (NOx) in a gas stream (29) in the presence of H2 is provided. The process comprises contacting the gas stream with a catalyst system (38) comprising zirconia-silica washcoat particles (41), a pre-sulfated zirconia binder (44), and a catalyst combination (40) comprising palladium and at least one of rhodium, ruthenium, or a mixture of ruthenium and rhodium.

Abstract: A process and system (18) for reducing NOx in a gas using hydrogen as a reducing agent is provided. The process comprises contacting the gas stream (29) with a catalyst system (38) comprising sulfated zirconia washcoat particles (41), palladium, a pre-sulfated zirconia binder (44), and a promoter (45) comprising at least one of titanium, zinc, or a mixture thereof. The presence of zinc or titanium increases the resistance of the catalyst system to a sulfur and water-containing gas stream.