Patent classifications
B01D2255/20723
SYSTEMS AND METHODS FOR INCREASING NITROGEN DIOXIDE FRACTION IN EXHAUST GAS AT LOW TEMPERATURE
An aftertreatment system includes a first oxidation catalyst, a second oxidation catalyst, and a turbocharger. The first oxidation catalyst is upstream of the turbocharger and includes a first oxidation catalyst formulation. The second oxidation catalyst is downstream of the turbocharger and includes a second oxidation catalyst formulation different than the first oxidation catalyst formulation. The second oxidation catalyst formulation is configured to promote conversion of nitric oxide (NO) to nitrogen dioxide (NO.sub.2).
Process for the preparation of 1,3,3,3-tetrafluoropropene
Disclosed is a process for the preparation of 1,3,3,3-tetrafluoropropene, comprising: (a) a compound having the formula CF.sub.3-xCl.sub.xCHClCHF.sub.2-yCl.sub.y and in the presence of a compound catalyst, undergoes, through n serially-connected reactors, gas-phase fluorination with hydrogen fluoride, producing 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane; in said formula, x=1, 2 or 3; y=1 or 2, and 3x+y5; (b) 1,2,3-trichloro-1,1,3-trifluoropropane, and 1,2-dichloro-1,1,3,3-tetrafluoropropane undergo, in the presence of a dehalogenation catalyst, gas-phase dehalogenation with hydrogen, producing 3-chloro-1,3,3-trifluoropropene, and 1,1,3,3-tetrafluoropropene; (c) 3-chloro-1,3,3-trifluoropropene and 1,1,3,3-tetrafluoropropene undergo, in the presence of a fluorination catalyst, gas-phase fluorination with hydrogen fluoride, producing 1,3,3,3-tetrafluoropropene. The present invention is primarily used to produce 1,3,3,3-tetrafluoropropene.
COATED ARTICLES HAVING HIGH KNOx/KSOx RATIOS FOR SELECTIVE CATALYTIC REDUCTION
Articles comprising a catalyst film comprising VOx, MoO.sub.3 or WO.sub.3, and TiO.sub.2 deposited on a substrate are disclosed. The articles are useful for selective catalytic reduction (SCR) of NOx in exhaust gases. Methods for producing such articles deposit a catalyst film on the substrate to form a coated substrate, which is then calcined. When used in an SCR process, the coated articles have enhanced activity for NOx conversion, reduced activity for SOx conversion, or both. Light-weight, coated articles having high catalyst loads can be fabricated at the same or reduced dimensions when compared with laminated articles, and increased kNOx/kSOx ratios are available even from coated articles having relatively thin catalyst films. The articles should have particular value for power plant operations, where coal and high-sulfur fuels are commonly used and controlling sulfur trioxide generation is critical.
CATALYST BINDERS FOR FILTER SUBSTRATES
Provided is a catalyst washcoat comprising (i) a molecular sieve loaded with about 1 to about 10 weight percent of at least non-aluminum promoter metal (wherein the promoter metal weight percent is based on the weight of the molecular sieve); and (ii) about 1 to about 30 weight percent of a binder having a d90 particle size of less than 10 microns (wherein the binder weight percent is based on the total weight of the washcoat). In another aspect of the invention, the catalyst washcoat is applied to a wall-flow filter to form a catalyst article. In another aspect of the invention the catalyst article is part of an exhaust gas treatment system. And in yet another aspect of the invention, provided is a method for treating exhaust gas using the catalyst article.
SYSTEMS AND METHODS FOR EXTRACTING AND REMOVING HYDROGEN SULFIDE AND THIOLS
Compositions and methods for the removal of hydrogen sulfide, vapor phase thiols, carbonyl sulfide, and combinations thereof, from gas/vapor streams are provided through the utilization of a regenerable formulated media. The compositions may include a bound complex treated-activated carbon media (BCT-AC media). The compositions and methods provide advantages over current known technologies by reducing the number of required process steps and resulting reduction in capital and operating costs, as well as elimination of aqueous phase processes that are expensive to operate and generate unwanted waste by products. Additionally, the compositions and methods provided remove hydrogen sulfide as recoverable elemental sulfur and are ideally suited for gas/vapor phase applications where carbon dioxide may be present as it has no process or economic impact on the compositions or methods.
DEVICE SYSTEM AND METHOD HAVING SINTERING FLUE GAS CO CATALYTIC HEAT EXCHANGE AND MEDIUM-AND-LOW-TEMPERATURE SCR DENITRATION CONNECTED IN SERIES
Disclosed in the present invention are a device system and method having sintering flue gas CO catalytic heat exchange and medium-and-low-temperature SCR denitration connected in series. In the device system, a CO catalytic heat storage and exchange device is arranged to completely replace an original heat exchanger arranged after a raw desulfurized flue gas pipe. The method comprises respectively carrying out first CO catalytic conversion and second CO catalytic conversion on sintering flue gas and denitrated flue gas by means of the CO catalytic heat storage and exchange device, thereby increasing CO conversion efficiency and reducing overall resistance of the system. In addition, the present invention takes both CO pollution control and carbon emission reduction into consideration and thus has good economic benefits and a good application prospect.
Exhaust gas purifying catalyst
This exhaust gas purifying catalyst is provided with a substrate and a catalyst layer formed on a surface of the substrate. The catalyst layer contains zeolite particles that support a metal, and a rare earth element-containing compound that contains a rare earth element. The rare earth element-containing compound is added in such an amount that the molar ratio of the rare earth element relative to Si contained in the zeolite is 0.001 to 0.014 in terms of oxides.
MOLECULAR SIEVE CATALYST COMPOSITIONS, CATALYST COMPOSITES, SYSTEMS, AND METHODS
Described is a selective catalytic reduction material comprising a spherical particle including an agglomeration of crystals of a molecular sieve. The catalyst is a crystalline material that is effective to catalyze the selective catalytic reduction of nitrogen oxides in the presence of a reductant at temperatures between 200 C. and 600 C. A method for selectively reducing nitrogen oxides and an exhaust gas treatment system are also described.
Catalyst filter comprising nano metallic catalyst sprayed on the surface of support
Disclosed is a catalyst filter, which includes a catalyst support and a nano metallic catalyst sprayed to a surface of the catalyst support. The catalyst filter uses catalyst slurry prepared by using a particulate catalyst, in which a small amount of nano metallic catalyst exhibiting a catalyst performance is sprayed to a surface of the catalyst support, different from an existing patent technique in which catalyst particles are formed and prepared as a support to consume a large amount of catalyst. Therefore, the specific surface area of the catalyst filter is not smaller than the specific surface area of the nano catalyst particles, and thus the catalyst filter may effectively remove and decompose ultra-low concentration gas-state contaminants in an indoor air.
Exhaust gas post-processing system
An exhaust gas post-processing system includes an oxidation catalyst configured to oxidize substances included in the exhaust gas; a diesel particulate filter configured to collect particulate matters included in the exhaust gas and disposed subsequent to the oxidation catalyst; a dosing module configured to inject a reducing agent and disposed subsequent to the diesel particulate filter; and a selective catalytic reduction configured to remove nitrogen oxide using the reducing agent included in the exhaust gas and disposed subsequent to the dosing module. The diesel particulate filter includes a catalytic component represented by La.sub.1-xAg.sub.xMnO.sub.3 (where 0<x<1).