Selective catalytic reduction of NOx by low-temperature NH3 over MnxZr1 mixed-oxide catalysts

MnxZr1 series catalysts were prepared by a coprecipitation method.

Selective Catalytic Reduction of NOx Over Hierarchical Cu-ZSM-5 Coated on Ceramic Foam Support

The development of structured catalysts for process intensification is of growing interest in catalytic processes due to heat and mass transfer limitations at an industrial scale. This limitation can be...

Jet-Niche Technology Influence Potential on the Economic and Operating Parameters of the Fire-Engineering Equipment

The Power engineering is an inseparable part of the contemporary world that has a negative influence on the ecology; in particular it provokes the pollution of atmosphere with such harmful emissions as nitrogen and carbon oxides. Different methods are used to reduce the emission of harmful substances. The efficiency of such methods is increased when these are used in combination and not separately. The recirculation of flue gases and the use of contemporary technologies for municipal boilers, in particular jet-niche technology (JNT) enabled the reduction of NOx and СО emissions to the levels that meet the requirements of European standards simultaneously improving the efficiency of the operation of the fire-engineering facility. The principle of operation of the JNT is based on the formation of the compact stable self-controlled vortex structure and on the interaction system of flammable and oncoming oxidizer flows. This technology enables the operation at minimum recirculation values and it means that all boiler parameters can be retained, in particular starting characteristic, combustion stability and unavailability of vibration modes including a high level of fuel burnout. The obtained research data showed that NОх values were in the range of 80 to 140 mg/m3 when the oxygen content at the furnace inlet was 20% and lower for different boiler systems (DKBR-10, KVGM-6.5, PTVM-50) at CO values close to 50 mg/m2. Hence, the use of the burners of a JNT type enables the reduction of NОхemissions and retains the combustion process efficiency.

Solid Selective Catalytic Reduction: A Promising Approach towards Reduction of NOx Emission from Exhaust of CI Engines

The rising rate of pollution in urban areas has become a worldwide concern in recent years. Diesel engines are considered one of the largest contributors to environmental pollution caused by exhaust emissions, and they are responsible for several health problems as well. Diesel engines contain carbon monoxide, carbon dioxide, unburned hydrocarbons, and oxides of nitrogen. The reduction of Nitric oxides (NOx) emission from diesel engine exhaust is currently being researched by automotive manufacturers. After much research, selective catalytic reduction (SCR) technology was discovered to be effective in reducing nitrogen oxide emission from diesel engine exhaust. This paper is an attempt to explore the problems associated with the use of selective catalytic reduction (SCR) and compares selective catalytic reduction (SCR) with the latest technology named solid selective catalytic reduction (SSCR) for efficient reduction of NOx emission from the exhaust of diesel engines. The issue of contamination, malfunctioning, and freezing of diesel exhaust fluid (DEF) at low temperatures are the major problems associated with the application of SCR. It is observed that by controlling the quantity of ammonia slip, SSCR can give better performance in the reduction of NOx emission from the exhaust of diesel engines.