Abstract:
A first NOx adsorption material 20 exhibiting a peak temperature being 200° C. or less at which an elimination amount of adsorbed NOx becomes the maximum is put in place on an exhaust-gas upstream side, and a second NOx adsorption material 21 exhibiting a peak temperature surpassing 200° C. at which an elimination amount of adsorbed NOx becomes the maximum is put in place on an exhaust-gas downstream side of the first NOx adsorption material 20. In low-temperature region, NOx are adsorbed on the first NOx adsorption material 20; and, in high-temperature region, NOx having been eliminated from the first NOx adsorption material 21 are adsorbed on the second NOx adsorption material 21 again. Therefore, it is possible to adsorb NOx form low-temperature region and up to high-temperature region efficiently, and thereby an amount of NOx being discharged from an NOx reduction catalyst to be put in place on a downstream-side thereof is reduced.
Abstract:
Process, apparatus and article for treating an aqueous solution containing biological contaminants. The process includes contacting an aqueous solution containing a biological contaminant with an aggregate composition comprising an insoluble rare earth-containing compound to form a solution depleted of active biological contaminants. The aggregate includes more than 10.01% by weight of the insoluble rare earth-containing compound. The insoluble rare earth-containing compound can include one or more of cerium, lanthanum, or praseodymium. A suitable insoluble cerium-containing compound can be derived from a cerium carbonate, a cerium oxalate or a cerium salt. The composition can consist essentially of cerium oxides, and optionally, a binder and/or flow aid. The aggregate includes no more than two elements selected from the group consisting of yttrium, scandium, and europium when the aggregate is to be sintered. Although intended for a variety of fluid treatment applications, such applications specifically include removing or deactivating biological contaminants in water.
Abstract:
Rare earth metal compounds, particularly lanthanum, cerium, and yttrium, are formed as porous particles and are effective in binding metals, metal ions, and phosphate. A method of making the particles and a method of using the particles is disclosed. The particles may be used in the gastrointestinal tract or the bloodstream to remove phosphate or to treat hyperphosphatemia in mammals. The particles may also be used to remove metals from fluids such as water.
Abstract:
Methods of manufacturing bentonite sorbents for removal of pollutants including mercury from gas streams, such as a flue gas stream from coal-fired utility plants are disclosed. The methods include mixing bentonite sorbent particles with a sulfide salt and a metal salt to form a metal sulfide on the outer surface of the bentonite sorbent particles.
Abstract:
Provided is an ambient temperature NOx adsorbent. The ambient temperature NOx adsorbent comprises a support and a metal supported on the support. The support comprises at least one metal oxide selected from oxides of Co, Fe, Cu, Ce, Mn, and a combination thereof. The supported metal comprises at least one metal selected from Cu, Co, Ag, Pd, and a combination thereof. The metal oxide is easily changed the oxidation number and has oxygen absorptive/emissive properties. The supported metal has an oxidative activity and is highly adsorptive to NO. Oxygen supplied from the metal oxide converts the supported metal to a peroxidized form of the supported metal. Hence, NO is readily adsorbed to the supported metal at ambient temperature around room temperature. The adsorbed NO is easily oxidized to NO2 by oxygen supplied from the metal oxide or the supported metal in a peroxidized state in the absence of oxygen in an ambient atmosphere. The NO2 is then efficiently adsorbed to the metal oxide. That is, the ambient temperature NOx adsorbent can adsorb a sufficient amount of NOx even at ambient temperature around room temperature.
Abstract:
A system for use in the removal of heavy metal contaminants from fluid is provided. The system includes a source from which contaminated fluid may be introduced into the system, a first station for removal by physical separation of a targeted heavy metal contaminant from the flow of fluid, including elemental species of the targeted heavy metal contaminant, and a second station positioned downstream of the first station and in fluid communication therewith for adsorptive separation of the targeted heavy metal contaminant from the fluid flow, including additional amount of the elemental species along with the other species of the targeted heavy metal contaminant. A method for removing heavy metal contaminants from fluid is also provided.
Abstract:
Compositions and methods suitable for removing poisonous metals from hydrocarbons are provided. The compositions comprise hydrotalcite having one or more trapping metals dispersed on the outer surface thereof.
Abstract:
Disclosed is a doped cerium oxide sorbent that can effectively and regenerably remove H2S in the temperature range of about 500° C. to about 1000° C. Regenerable sorbents (e.g., ZnO, La2O3, CeO2) and methods of using them are disclosed that allow cyclic desulfurization from about 300-500° C., 350-450° C., and at about 400° C. In one embodiment, the present invention relates to a method of desulfurizing fuel gas comprising passing the fuel gas through the sorbent at a space velocity wherein the sulfur compounds are adsorbed substantially on the surface of the sorbent; and regenerating the sorbent by passing a regenerating gas through the sorbent, wherein substantially all of the sulfur compounds are desorbed from the sorbent surface. In a further embodiment, the method of desulfurizing fuel gas further comprises repeating the aforementioned steps while the fuel processor is in operation. In another embodiment, the step of passing the fuel gas may be preceded by reducing the sorbent by passing a reducing gas through the sorbent. In another embodiment, the sorbent may be fully sulfided, i.e., sulfided on its surface and bulk (internally).
Abstract:
Compositions and methods for destroying biological agents such as toxins and bacteria are provided wherein the substance to be destroyed is contacted with finely divided metal oxide or hydroxide nanocrystals. In various embodiments, the metal oxide or metal hydroxide nanocrystals have reactive atoms stabilized on their surfaces, species adsorbed on their surfaces, or are coated with a second metal oxide. The desired metal oxide or metal hydroxide nanocrystals can be pressed into pellets for use when a powder is not feasible. Preferred metal oxides for the methods include MgO, SrO, BaO, CaO, TiO2, ZrO2, FeO, V2O3, V2O5, Mn2O3, Fe2O3, NiO, CuO, Al2O3, SiO2, ZnO, Ag2O, [Ce(NO3)3—Cu(NO3)2]TiO2, Mg(OH)2, Ca(OH)2, Al(OH)3, Sr(OH)2, Ba(OH)2, Fe(OH)3, Cu(OH)3, Ni(OH)2, Co(OH)2, Zn(OH)2, AgOH, and mixtures thereof.
Abstract translation:提供了用于破坏生物制剂如毒素和细菌的组合物和方法,其中待破坏的物质与细碎的金属氧化物或氢氧化物纳米晶体接触。 在各种实施方案中,金属氧化物或金属氢氧化物纳米晶体在其表面上具有稳定的反应性原子,吸附在其表面上的物质或用第二金属氧化物涂覆。 当粉末不可行时,可以将期望的金属氧化物或金属氢氧化物纳米晶体压制成颗粒使用。 用于该方法的优选金属氧化物包括MgO,SrO,BaO,CaO,TiO 2,ZrO 2,FeO,V 2 O 2, 3个O 2,5个2 O 3,3个O 2,3个3, 3,N 3,NiO,CuO,Al 2 O 3,SiO 2,ZnO,Ag < SUB> 2 ,[Ce(NO 3 3)3 -Cu(NO 3)2 SUB Mg(OH)2,Ca(OH)2,Al(OH)3 3, ,Sr(OH)2,Ba(OH)2,Fe(OH)3,Cu(OH)3, Ni(OH)2,Co(OH)2,Zn(OH)2,AgOH及其混合物。
Abstract:
Oxyanions of various contaminant elements, such as chromium, antimony, molybdenum, tungsten, vanadium and uranium, are removed from water and other aqueous feeds by treating the feed with (1) a sorbent comprising one or more rare earth compounds, usually mixed or supported on particulate solids having a cation exchange capacity less than 20 milliequivalents per 100 grams or (2) an aqueous solution of one or more soluble rare earth compounds.