Download or read book Non Catalytic NO x Removal from Gas Turbine Exhaust with Cyanuric Acid in a Recirculating Reactor written by Michael Streichsbier and published by . This book was released on 1997 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Non catalytic NOx Removal from Gas Turbine Exhaust with Cyanuric Acid in a Recirculating Reactor written by Michael Streichsbier and published by . This book was released on 1998 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Chemical Abstracts written by and published by . This book was released on 2002 with total page 2626 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selective Catalytic Reduction of NOx written by Oliver Kröcher and published by MDPI. This book was released on 2018-12-14 with total page 281 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is a printed edition of the Special Issue "Selective Catalytic Reduction of NOx" that was published in Catalysts
Download or read book Acid Precipitation written by and published by . This book was released on 1992-07 with total page 516 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Catalysts for Direct Decomposition of NOx in Exhausts written by and published by . This book was released on 2000 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Eltron Research, Inc., is pursuing the rational development of catalysts for direct (reagentless) decomposition of NOx. This is the most economical imaginable approach for post-combustion removal of nitrogen oxides because costs for reagent and reagent delivery (i.e., ducting, etc.) are eliminated, and catalysts demonstrating activity to the present time are inexpensive ($1-$4/lb). The decomposition of nitrogen oxides in simulated exhaust streams over new brownmillerite catalysts has been examined in a range of temperatures and residence times. Results are indicative of the occurrence of reagentless activity in gas streams containing up to 16 percent oxygen. Performance was nonmonotonic in temperature, with an activity maximum occurring between 550 and 600 deg C. For example, up to 90% conversion of NOx at 250 deg C and 130,000/h has been attained. Using CO as a reductant at 800,000/h and 1000 deg C , one catalyst removed 16 percent of 477 ppm NO in a stream also containing 16 percent oxygen. These results suggest the potential efficacy of the catalysts for the direct decomposition of nitrogen oxides in high-temperature (400-1000 deg C) exhaust gases in, e.g., gas turbine and diesel engines. In addition, the catalysts were found to be effective at oxidizing CO. The enhancement of activity obtained using carbon monoxide is particularly relevant in such applications.
Download or read book Plasma Assisted Heterogeneous Catalysis for NOx Reduction in Lean Burn Engine Exhaust written by B. Penetrante and published by . This book was released on 1997 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent developments in catalytic control of NOx are revealing the significance of NO2 as an intermediary for achieving higher NOx removal efficiencies. This paper discusses the combination of the plasma with a catalyst to improve the selective reduction of NOx under lean-burn conditions. It is shown that the main effect of the plasma is to enhance the gas-phase oxidation of NO to NO2. The reduction of NOx to N2 is then accomplished by the heterogeneous reaction of NO2 with activated hydrocarbons on the catalyst surface. By using a plasma, one can take advantage of a new class of catalysts that are potentially more durable, more active, more selective and more sulfur-tolerant compared to conventional lean-NOx catalysts. The plasma-assisted catalytic reduction process can be implemented with any type of plasma reactor and does not require a specific type of electrical power supply. It can also easily accommodate any type of catalyst support structure.
Download or read book Simultaneous Catalytic Removal of Diesel Soot and Nox written by Wenfeng Shangguan and published by Energy and Environment Researc. This book was released on 2019-07-28 with total page 140 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Plasma Regenerated Particulate Trap and NO sub x Reduction System written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A non-catalytic two-stage process for removal of NO.sub.x and particulates from engine exhaust comprises a first stage that plasma converts NO to NO.sub. 2 in the presence of O.sub. 2 and hydrocarbons, and a second stage, which preferably occurs simultaneously with the first stage, that converts NO.sub. 2 and carbon soot particles to respective environmentally benign gases that include N.sub. 2 and CO.sub. 2. By preconverting NO to NO.sub. 2 in the first stage, the efficiency of the second stage for NO.sub.x reduction is enhanced while carbon soot from trapped particulates is simultaneously converted to CO.sub. 2 when reacting with the NO.sub. 2 (that converts to N.sub. 2). For example, an internal combustion engine exhaust is connected by a pipe to a chamber where carbon-containing particulates are electrostatically trapped or filtered and a non-thermal plasma converts NO to NO.sub. 2 in the presence of O.sub. 2 and hydrocarbons. Volatile hydrocarbons (C.sub.x H.sub.y) from the trapped particulates are oxidized in the plasma and the remaining soot from the particulates reacts with the NO.sub. 2 to convert NO.sub. 2 to N.sub. 2, and the soot to CO.sub. 2. The nitrogen exhaust components remain in the gas phase throughout the process, with no accompanying adsorption.
Download or read book Fundamental Studies of Catalytic NOx Removal written by Louise Olsson and published by . This book was released on 2002 with total page 65 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Process for the Removal of Acid Forming Gases from Exhaust Gases written by and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Exhaust gases are treated to remove NO or NO.sub.x and SO.sub. 2 by contacting the gases with an aqueous emulsion or suspension of yellow phosphorus preferably in a wet scrubber. The pressure is not critical, and ambient pressures are used. Hot water temperatures are best, but economics suggest about 50.degree. C. are attractive. The amount of yellow phosphorus used will vary with the composition of the exhaust gas, less than 3% for small concentrations of NO, and 10% or higher for concentrations above say 1000 ppm. Similarly, the pH will vary with the composition being treated, and it is adjusted with a suitable alkali. For mixtures of NO.sub.x and SO.sub. 2, alkalis that are used for flue gas desulfurization are preferred. With this process, 100% of the by-products created are usable, and close to 100% of the NO or NO and SO.sub. 2 can be removed in an economic fashion.
Download or read book Catalytic Decomposition of Nitric Oxide and Carbon Monoxide Gases Using Nanofiber Based Filter Media of Varying Diameters written by Renee Lynn Petty and published by . This book was released on 2010 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nitrogen Oxide (NO) and carbon monoxide (CO) are major pollutants in the exhaust streams of automobiles, power plants, and other combustion processes. The growing concerns for the environment have resulted in increasingly restrictive emission standards. The removal of NO and CO from exhaust gases is a challenging task. One method for harmful gas removal is using a catalyst for dissociation. This work explored an alternative method for catalytic reduction of NO. Polymer solutions with palladium catalyst and ceramic precursors were electrospun to form polymer nanofibers. These nanofibers were heated to form ceramic nanofibers with catalyst nanoparticles and were mixed with microfibers to form a nonwoven fibrous catalyst support structure. The concentration of the polymer was varied to create nanofibers with diameters ranging from 100 to 700 nm with a constant mass of catalyst particles per mass of fiber. The effect of the fiber diameter on the corresponding catalyst structure performance was tested. A surface area comparison test was completed to determine whether the reactions occur strictly on the surface of the catalyst or if diffusion occurs. An aging comparison was also completed which tested 1 week old catalytic filters compared to 6 months old. A conventional catalytic converter was tested to verify the performance was similar to the catalytic fibrous filter media containing only palladium. Experiments were carried out using a lab reactor to expose the media to a mixture of gases simulating an exhaust stream at room temperature to a maximum of 450°C. The reactor exhaust concentrations are measured using gas chromatography (GC) to determine the catalyst performance. Results indicated that the catalytic reaction performance was about the same for fiber sizes ranging from 100 to 700 nm on a mass basis with a reduction temperature of 325-350°C. The surface area comparison filter reduced at 275°C which showed that both surface catalyst particles and particles within the fibers are available for reaction. Furthermore, a conventional catalytic converter reduced at approximately 325°C which exhibits comparable catalytic performance with the catalytic filters. Model theory and equations were also developed for decomposition reactions of NO and CO using elementary reactions.
Download or read book Exhaust Aftertreatment Using Plasma assisted Catalysis written by and published by . This book was released on 2000 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In the field of catalysis, one application that has been classified as a breakthrough technology is the catalytic reduction of NO(subscript x) in oxygen-rich environments using hydrocarbons. This breakthrough will require dramatic improvements in both catalyst and engine technology, but the benefits will be substantial for energy efficiency and a cleaner environment. Engine and automobile companies are placing greater emphasis on the diesel engine because of its potential for saving fuel resources and reducing CO2 emissions. The modern direct-injection diesel engine offers demonstrated fuel economy advantages unmatched by any other commercially-viable engine. The main drawback of diesel engines is exhaust emissions. A modification of existing oxidation catalyst/engine technology is being used to address the CO, hydrocarbon and particulates. However, no satisfactory solution currently exists for NO(subscript x). Diesel engines operate under net oxidizing conditions, thus rendering conventional three-way catalytic converters ineffective for the controlling the NO(subscript x) emission. NO(subscript x) reduction catalysts, using ammonia as a reductant, do exist for oxygen-rich exhausts; however, for transportation applications, the use of on-board hydrocarbon fuels is a more feasible, cost-effective, and environmentally-sound approach. Selective catalytic reduction (SCR) by hydrocarbons is one of the leading catalytic aftertreatment technologies for the reduction of NO(subscript x) in lean-burn engine exhaust (often referred to as lean-NO(subscript x)). The objective is to chemically reduce the pollutant molecules of NO(subscript x) to benign molecules such as N2. Aftertreatment schemes have focused a great deal on the reduction of NO because the NO(subscript x) in engine exhaust is composed primarily of NO. Recent studies, however, have shown that the oxidation of NO to NO2 serves an important role in enhancing the efficiency for reduction of NO(subscript x) to N2. It has become apparent that preconverting NO to NO2 could improve both the efficiency and durability of lean-NO(subscript x) catalysts. A non-thermal plasma is an efficient means for selective partial oxidation of NO to NO2. The use of a non-thermal plasma in combination with a lean-NO(subscript x) catalyst opens the opportunity for catalysts that are more efficient and more durable compared to conventional catalysts. In the absence of hydrocarbons, the O radicals will oxidize NO to NO2, and the OH radicals will further oxidize NO2 to nitric acid. In plasma-assisted catalysis it is important that the plasma oxidize NO to NO2 without further producing acids.
Download or read book Catalyctic Reduction of Nitric Oxide by Copper Catalyzed Granular Activated Carbon in the Presence of Oxygen written by Shan Xio and published by . This book was released on 1999 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: The catalytic reduction of nitric oxides by solid carbonaceous material consisting primarily of granular activated carbon or (GAC) was studied in a fix bed catalytic reactor in order to develop the technology for removing NO and soot simultaneously from diesel engine exhaust. The catalytic activity and conversion of NO as a function of reaction temperature was evaluated as a function of space velocity. The results show that at lean condition and high gaseous hourly space velocity, vis., 50,000 ~ 80,000, Cu-ZSM-5 does not perform as well with CO and GAC as it does with gaseous hydrocarbons(HC). Plain GAC has low activity for NO reduction at high temperature above 550°C under lean condition. However, copper-impregnated GAC has good activity for both NO reduction and carbon oxidation under lean conditions. Actually in presence of 1 to 10% oxygen, the activity and conversion of NO to N2 due to reaction with carbon is enhanced at a lower light off temperature of 350°C. Over 60% conversion was obtained at gaseous hourly space velocity of 50,000 ~ 80,000. Almost 100% conversion was obtained when GHSV was lowered to 20,000. In order to get insight on the mechanism of this reaction, the reduction of NO with CO was studied over various catalysts at the same condition. It was determined that the results are consistent with CO being an intermediate for the reduction of NO with carbon. We also investigated the deactivation of these catalysts. The results show that the presence of SO2 and water poison copper catalysts. For this reason, it is necessary to develop other catalysts for controlling both NOx and soot. This research is part of a NSF project for developing a novel technique to remove NOx soot simultaneously from diesel engines.
Download or read book Process for the Removal of Acid Forming Gases from Exhaust Gases and Production of Phosphoric Acid written by and published by . This book was released on 1992 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Exhaust gases are treated to remove NO or NO.sub.x and SO.sub. 2 by contacting the gases with an aqueous emulsion or suspension of yellow phosphorous preferably in a wet scrubber. The addition of yellow phosphorous in the system induces the production of O.sub. 3 which subsequently oxidizes NO to NO.sub. 2. The resulting NO.sub. 2 dissolves readily and can be reduced to form ammonium ions by dissolved SO.sub. 2 under appropriate conditions. In a 20 acfm system, yellow phosphorous is oxidized to yield P.sub. 2 O.sub. 5 which picks up water to form H.sub. 3 PO.sub. 4 mists and can be collected as a valuable product. The pressure is not critical, and ambient pressures are used. Hot water temperatures are best, but economics suggest about 50.degree. C. The amount of yellow phosphorus used will vary with the composition of the exhaust gas, less than 3% for small concentrations of NO, and 10% or higher for concentrations above say 1000 ppm. Similarly, the pH will vary with the composition being treated, and it is adjusted with a suitable alkali. For mixtures of NO.sub.x and SO.sub. 2, alkalis that are used for flue gas desulfurization are preferred. With this process, better than 90% of SO.sub. 2 and NO in simulated flue gas can be removed. Stoichiometric ratios (P/NO) ranging between 0.6 and 1.5 were obtained.
Download or read book Effect of Water Vapor on Toluene Removal in Catalysis DBD Plasma Reactors supported by the Key Project which is Sponsored by the Science and Technology Commission of Shanghai Municipality No 13231201903 the Key Programs for Science and Technology Development Sponsored by the Science and Technology Commission of Shanghai Municipality Nos 13231201901 and 14DZ1208401 and the Key Project Sponsored by the State owned Assets Supervision and Administration Commission of Shanghai China No 2013019 written by and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The experiment was carried out in a cylindrical dielectric barrier discharge (DBD) reactor assisted with a catalyst to decompose toluene under different humidity. In order to explore the synergistic effect on removing toluene in the catalysis-DBD reactor, this paper investigated the decomposition efficiency and the energy consumption in the catalysis-DBD and the non-catalyst DBD reactors under different humidity. The results showed that the catalysis-DBD reactor had a better performance than the non-catalysis one at the humidity ratio of 0.4%, and the removal efficiency of toluene could reach 88.6% in the catalysis-DBD reactor, while it was only 59.9% in the non-catalytic reactor. However, there was no significant difference in the removal efficiency of toluene between the two reactors when the humidities were 1.2% and 2.4%. Additionally, the degradation products were also analyzed in order to gain a better understanding of the mechanism of decomposing toluene in a catalysis-DBD reactor.
Download or read book The Pennsylvania Pocket Almanack for the Year 1774 written by William Bradford and published by . This book was released on 1773 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:
