4,872 Results Found

V_0.5/Pt/TiO₂ tandem catalysts exhibit both an outstanding low-temperature NH₃ conversion rate and high N₂ selectivity in NH₃-SCO reactions, but the mechanism of high N₂ selectivity remains unclear. In this work, V_x/Pt/TiO₂ tandem catalysts were synth...

Partial hydrogenation of benzene is the main approach to cyclohexene synthesis in industry. Here, the reaction mechanisms of benzene hydrogenation on Pd-Zn bimetallic catalysts were studied using density functional theory, with the aim of understandi...

Transition metal oxides, particularly NiFe(OH)₂, are recognized for their high oxygen evolution reaction (OER) activity and structural stability. However, their performance in natural seawater electrolysis remains insufficiently studied. Manganese di...

Metal–organic frameworks (MOFs) are a novel type of porous crystalline materials assembled from metal ions and organic linkers. Their derivatives can inherit characteristics such as high specific surface area, tunable porosity, and unique topol...

The significance of the selective catalytic reduction system in vehicles increases in line with the high standards of emission control and enhanced selective catalytic reduction efficiency. This study aims to improve the performance of the selective...

Nitrogen oxides released from the combustion of fossil fuels are one of the main air pollutants. Selective catalytic reduction technology is the most widely used nitrogen oxide removal technology in the industry. With the development of nanomaterials...

The selective catalytic reduction of NO with NH₃ at low temperatures has been investigated with natural iron ore catalysts. Four iron ore raw materials from different locations were taken and processed to be used as catalysts. The methods of X-ray di...

Tailoring the shape of nanoscale materials enables obtaining morphology-controlled surfaces exhibiting specific interactions with reactants during catalytic reactions. The specifics of nanoparticle surfaces control the catalytic performance, i.e., ac...

Selective catalytic reduction of nitrogen oxides with NH₃ (NH₃-SCR) is still the most commonly used control technology for nitrogen oxides emission. Specifically, the application of rare earth materials has become more and more extensive. CeO₂ was wi...

In this study, we synthesized V₂O₅-WO₃/TiO₂ catalysts with different crystallinities via one-sided and isotropic heating methods. We then investigated the effects of the catalysts’ crystallinity on their acidity, surface species, and catalytic perfor...

A series of catalytic coatings consisting of MnO_x-CeO₂ and TiO₂ support were prepared by atmospheric plasma spraying, which was aimed at the application of selective catalytic reduction (SCR) of NO_x. The effect of the load of active component on the...

Iron-based catalysts are regarded as promising candidates for the ammonia selective catalytic reduction reaction (NH₃-SCR) which show good catalytic activity at medium and high temperatures, whereas SAPO-34 molecular sieves have a micro-pore structur...

Barium and iridium supported on Zeolite Socony Mobil-5 (ZSM-5) are efficient catalysts for the selective catalytic reduction of nitric oxide by carbon monoxide (CO-SCR), with enhanced cyclic stability. The introduction of Ba hindered the oxidation of...

Cu/SSZ-13 Selective Catalytic Reduction (SCR) catalysts have been extensively studied for the past five-plus years. New and exciting fundamental and applied science has appeared in the literature quite frequently over this time. In this short review,...

In this study, CeZr_0.5Ti_aO_x (with a = 0, 1, 2, 5, 10) catalysts were prepared by a stepwise precipitation approach for the selective catalytic reduction of NO_x with NH₃. When Ti was added, all of the Ce-Zr-Ti oxide catalysts showed much better cataly...

Natural zeolite of the heulandite-type framework was modified with iron and tested as a catalyst for the selective catalytic reduction of nitrogen oxides with ammonia (NH₃-SCR) in the temperature range of 150–450 °C. The catalyst was prepared at a la...

In the present study, a series of CeO₂/TiO₂ catalysts were fabricated by dry ball milling method in the absence and presence of organic assistants, and their catalytic performances for the selective catalytic reduction (SCR) of NO by NH₃ were investi...

NH₃ selective catalytic reduction (NH₃-SCR) is the most prevalent and effective method for removing nitrogen oxides. Over the past few decades, manganese (Mn)-based catalysts have demonstrated strong catalytic activity and have been extensively studi...

Selective catalytic reduction of nitrogen oxides (NO_x) with ammonia (NH₃-SCR) has been implemented in response to the regulation of NO_x emissions from stationary and mobile sources above 300 °C. However, the development of NH₃-SCR catalysts activ...

Multicomponent oxide systems 800-Cu-Mg-Fe-O and 800-Cu-Mg-Fe-O-Ce were tested as catalysts of selective catalytic oxidation of ammonia to dinitrogen (NH₃-SCO) process. Materials were obtained by calcination of hydrotalcite-like compounds at temperatu...

Dielectric barrier discharge (DBD) could generate non-thermal plasma (NTP) with the advantage of fast reactivity and high energy under atmosphere pressure and low-temperature. The presented work investigated the selective catalytic reduction (SCR) of...

This work presents the methodology and accurate evaluation of ammonia concentration distribution measurements at the selective catalytic reduction (SCR) catalyst outlet cross-section. The uniformity of ammonia concentration is a crucial factor influe...

At present, the development of novel catalysts with high activity Selective Catalytic Reduction (SCR) reaction at the low temperature is still a challenge. In this work, the authors prepare CeO₂/quasi-MIL-101 catalysts with various amounts of deposit...

At present, the most commonly used denitration process is the selective catalytic reduction (SCR) method. However, in the SCR method, the service life of the catalyst is short, and the industrial operation cost is high. The selective catalytic oxidat...

This study contributes to a method based on an aqueous solution of ammonia direct injection for NO_x emissions control from internal combustion engines. Many previously published studies about deNO_x technology are based on selective catalytic reductio...

Metal–oxide interfaces play a prominent role in heterogeneous catalysis. Tailoring the metal–oxide interfaces effectively enhance the catalytic activities and thermal stability of noble metal catalysts. In this work, polyvinyl alcohol-pro...

We demonstrated highly efficient selective catalytic reduction catalysts by adopting the polyol process, and the prepared catalysts exhibited a high nitrogen oxide (NO_X) removal efficiency of 96% at 250 °C. The V₂O₅ and WO₃ catalyst nanoparticles...

A series of K_xH_1.1-xCu_0.2Cs₁(NH₄)_1.5PVMo₁₁O₄₀ (KxCuCsNH₄PVA) catalysts with different x values were synthesized to catalyze the selective oxidation of methacrolein (MAL) to methacrylic acid (MAA). The effects of potassium (K) ions on both the structu...

Selective catalytic reduction of NO_x with NH₃ (NH₃-SCR) has been successfully applied to abate NO_x from diesel engines and coal-fired industries on a large scale. Although V₂O₅-WO₃(MoO₃)/TiO₂ catalysts have been utilized in commercial applications, n...

This work aims to study the selective catalytic hydrogenation of vegetable oils to maximize oleic acid content and expand the range of non-edible uses. Oleic acid (C18:1) is suitable for use as a biodegradable lubricant and is a building block in pro...

This study presents modeling of selective catalytic reduction (SCR) for systems of diesel exhaust gases aftertreatment. The main purpose of this work is to develop the modeling approach that allows accurate prediction of urea–water solution beh...

Titanium modified FeMgO_x catalysts with different precursors were prepared by coprecipitation method with microwave thermal treatment. The iron precursor is a key factor affecting the surface active component. The catalyst using FeSO₄ and Mg(NO₃)₂ as...

Recently, air pollution has worsened throughout the world, and as regulations on nitrogen oxides (NO_x) are gradually tightened many researchers and industrialists are seeking technologies to cope with them. In order to meet the stringent regulations,...

Selective catalytic reduction (SCR) is the most efficient NO_X removal technology, and the vanadium-based catalyst is mainly used in SCR technology. The vanadium-based catalyst showed higher NO_X removal performance in the high-temperature range but ca...

A two-dimensional MnAl-layered double oxide (LDO) was obtained by flash nanoprecipitation method (FNP) and used for the selective catalytic reduction of NO_x with NH₃. The MnAl-LDO (FNP) catalyst formed a particle size of 114.9 nm. Further characteriz...

Selective catalytic reduction (SCR) with NH₃ is the most efficient and economic flue gas denitrification technology developed to date. Due to its high low-temperature catalytic activity, Mn-based catalysts present a great prospect for application in...

The cerium and/or zirconium-doped Cu/ZSM-5 catalysts (CuCe_xZr_1−xO_y/ZSM-5) were prepared by ion exchange and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), temperature-pr...

The poisoning effects of alkali metals (K and Na) and alkaline earth metals (Ca and Mg) on catalytic performance of the 2Nb4Ce/Zr-PILC catalyst for the selective catalytic reduction of NO_x with NH₃ (NH₃-SCR) were investigated, and physicochemical pro...

The uniformity of ammonia is very crucial for reducing the NO_X emissions in a selective catalytic reduction system since the uniformity highly affects the chemical reaction between the ammonia and NO_X emission. However, increasing ammonia uniformity...

During active mining operation of a gassy underground mine, large amounts of methane will be released from the mine ventilation shaft. To eliminate the harmful effects of this ventilation air methane and minimize the wastage of this potential energy...

Spent selective catalytic reduction (SCR) catalyst installed in power and incineration plants is used to convert nitrogen oxide (NO_x) gas to nitrogen (N₂) gas. Currently, most spent SCR catalyst in South Korea is eventually discarded in landfills. Re...

The Fe/(SZr) and S(Fe/Zr) sulfated iron-based catalysts, prepared by impregnation methods through changing the loading order of Fe₂O₃ and SO₄²⁻ on ZrO₂, were investigated on selective catalytic reduction (SCR) of NO_x by ammonia. It was studied...

The selective catalytic reduction (SCR) has been widely used in industrial denitrification owing to its high denitrification efficiency, low operating costs, and simple operating procedures. However, coal containing a large amount of sulfur will prod...

Based on the 2019 report of the European Environment Agency on Air Quality in Europe nitrogen oxides (NO_x) were identified as the most harmful air pollutants in terms of damage to ecosystems. Moreover, in Europe, NO₂ is pinpointed as one of the most...

Selective catalytic reduction of NO_x with NH₃ (NH₃-SCR) has been widely investigated to reduce NO_x emissions from combustion processes, which cause environmental challenges. However, most of the current work on NO_x reduction has focused on using feed...

Mn-based oxides are promising catalysts for the selective catalytic reduction (SCR) of NO_x by NH₃ at low temperatures. However, fundamental NH₃-SCR mechanisms and resistance mechanisms against SO_x remain controversial. This study employed density fun...

Artificial nitrogen oxide (NO_x) emissions due to the combustion of fossil fuels constitute more than 75% of the total NO_x emissions. Given the continuous reinforcement of NO_x emission standards worldwide, the development of environmentally and econom...

In this study, Mn-based catalysts supported by highly porous silica gel powder (SSA up to 470 m²·g⁻¹ and total pore volume up to 0.8 cm³·g⁻¹) were prepared by six different methods in liquid solutions (electroless metal deposition, stepwise addition...

The selective removal of electron-rich emerging organic contaminants (EOCs) from aquatic environments remains a critical challenge, as conventional radical-based oxidation processes suffer from poor selectivity and interference from background consti...

In this experimental investigation, a procreation approach was used to produce a catalyst based on SnO₂@rGO nanocomposite for use in a selective catalytic reduction (SCR) system. Plastic waste oil is one such alternative that helps to ensure the surv...