Nano-particle Characteristic Emitted from Gasoline Direct Injection Engine Equipped with Non-Thermal Plasma Device

The impact of non-thermal plasma (NTP) on particulate matter (PM) removal, nitrogen oxide (NOx) reduction, and hydrocarbon species in exhaust gases from gasoline direct injection (GDI) engines using gasoline E20 fuel and a mean effective pressure (IMEP) of 6 bar. The experiments were conducted with an exhaust gas flow rate of 20 L/min, applying high voltage in the range of 0 to 10 kV (2 kV per step) at a frequency of 500 Hz. The results show that NTP reduces PM concentrations, particularly in the nucleation mode (10 nm particles). Maximum PM removal of approximately 83% However, with experimental results, compared to 0 kV, the production of particulate matter Aitken mode increased up to 19 times for a voltage increase of 10 kV, and NOx removal has been at a maximum of about 9.5%, with an energy density of 5 J/L at 10 kV. The effects of NTP on hydrocarbon species such as ethylene, propylene, acetylene, 1.3 butadiene, methane, and ethane have been slightly affected by increased high voltages

Activity for Diesel Particulate Matter Oxidation of Silver Supported on Al2O3, TiO2, ZnO, and CeO2: The Effect of Oxygen Concentration

Particulate matter (PM) is a problem for human health the major producer of PM are diesel engines. The diesel particulate filters (DPFs) are used for the limitation of the PM. The DPF operation consists of two sequential functions: PM filtering and regeneration. One of the main contributing factors affecting the regeneration of DPF is the oxygen concentration in the exhaust gas. This study investigates the impact of different oxygen concentrations (99.99%, 10%, and 5%) on (PM) oxidation when using silver catalysts supported on CeO2, ZnO, TiO2, and Al2O3. The synthesized catalysts were characterized using XRD, SEM, SEMEDX, and H2-TPR techniques, and the PM oxidation activity was evaluated using TGA. The results demonstrated that different oxygen concentrations had little effect on light VOCs oxidation compared to no catalyst or the same catalyst. However, heavy VOCs and soot combustion, which require a higher oxygen concentration, significantly reduce combustion performance when the oxygen concentration decreases

The Influence of Direct Non-Thermal Plasma Treatment on Soot Characteristics under Low Exhaust Gas Temperature

This study aimed to assess the effectiveness of nonthermal plasma (NTP) technology utilizing a dielectric barrier discharge (DBD) reactor, both with and without exhaust gas recirculation (EGR), in reducing soot particles and their impact on nitrogen oxides (NOx). The experiment involved maintaining a constant flue gas flow rate of 10 l/min, employing high voltage values of 0, 6, and 10 kV, fixed frequency of 500 Hz and setting the various IMEP of 5, 6, and 7 bar and the engine speed at 2,000 rpm. The findings demonstrated that NTP was successful in removing NOx by approximately 16.84% and 17.01%, achieving particle matter (PM) removal efficiencies of around 60.79% and 81.13%, and effectively reducing activation energy by approximately 18.34% and 31.5% (with and without EGR, respectively) at a high voltage of 10 kV. These results highlight the potential of NTP technology in mitigating emissions and reducing the environmental impact associated with diesel engines

Modelling of catalytic aftertreatment of NOx emissions using hydrocarbon as a reductant

Hydrocarbon selective catalytic reduction (HC-SCR) is emerging as one of the most practical methods for the removal of nitrogen oxides (NOx) from light-duty-diesel engine exhaust gas. In order to further promote the chemical reactions of NOx-SCR by hydrocarbons, an understanding of the HC-SCR process at the molecular level is necessary. In the present work, a novel surface-reaction mechanism for HC-SCR is set up with emphasis on microkinetic analysis aiming to investigate the chemical behaviour during the process at a molecular level via detailed elementary reaction steps. Propane (C3H8) is chosen as the reductant of HC-SCR. The simulation is designed for a single channel of a monolith, typical for automotive catalytic converters, coated with a silver alumina catalyst (Ag/Al2O3). The complicated physical and chemical details occurring in the catalytic converter are investigated by using the numerical method of computational fluid dynamics (CFD) coupled with the mechanism. The C3H8-SCR reaction mechanism consists of 94 elementary reactions, 24 gas-phase species and 24 adsorbed surface species. The mechanism is optimised by tuning some important reaction parameters against some measurable data from experiments. The optimised mechanism then is validated with another set of experimental data. The numerical simulation shows good agreements between the modelling and the experimental data. Finally, the numerical modelling also provides information that is difficult to measure for example, gas-phase concentration distribution, temperature profiles, wall temperatures and the occupation of adsorbed species on catalyst surface. Consequently, computational modelling can be used as an effective tool to design and/or optimise the catalytic exhaust aftertreatment system

Soot Oxidation in Diesel Exhaust on Silver Catalyst Supported by Alumina, Titanium and Zirconium

Diesel Particulate Filter (DPF) is used to limit the emission of particulate matter (PM). The operation of DPF has two consecutive functions which are filtration of PM and regeneration. Performance of DPF is reduced by clogging of the filter. This problem is improved by soot oxidation in the regeneration process. The soot is completely oxidized by oxygen when temperature is higher than 600 °C. However, the exhaust gas temperature in normal operating of the diesel engine is lower than the temperature of soot complete oxidation. The problem of low temperature in soot oxidation is improved by oxidation catalyst because the oxidation catalyst is used to reduce light of temperature in soot oxidation. The study’s purpose is to compare the oxidation activity of silver catalyst supported on alumina (Al2O3), Titanium oxide (TiO2), and Zirconium oxide (ZrO2). The compression of soot oxidation on silver catalyst loaded on several support which showed silver base on alumina was the best of soot oxidation compared with titanium oxide and zirconium oxide. The behaviour of soot oxidation in silver base on titanium oxide and zirconium oxide were similar activity

Nano-particle Characteristic Emitted from Gasoline Direct Injection Engine Equipped with Non-Thermal Plasma Device

The impact of non-thermal plasma (NTP) on particulate matter (PM) removal, nitrogen oxide (NOx) reduction, and hydrocarbon species in exhaust gases from gasoline direct injection (GDI) engines using gasoline E20 fuel and a mean effective pressure (IMEP) of 6 bar. The experiments were conducted with an exhaust gas flow rate of 20 L/min, applying high voltage in the range of 0 to 10 kV (2 kV per step) at a frequency of 500 Hz. The results show that NTP reduces PM concentrations, particularly in the nucleation mode (10 nm particles). Maximum PM removal of approximately 83% However, with experimental results, compared to 0 kV, the production of particulate matter Aitken mode increased up to 19 times for a voltage increase of 10 kV, and NOx removal has been at a maximum of about 9.5%, with an energy density of 5 J/L at 10 kV. The effects of NTP on hydrocarbon species such as ethylene, propylene, acetylene, 1.3 butadiene, methane, and ethane have been slightly affected by increased high voltages

Activity for Diesel Particulate Matter Oxidation of Silver Supported on Al

Particulate matter (PM) is a problem for human health the major producer of PM are diesel engines. The diesel particulate filters (DPFs) are used for the limitation of the PM. The DPF operation consists of two sequential functions: PM filtering and regeneration. One of the main contributing factors affecting the regeneration of DPF is the oxygen concentration in the exhaust gas. This study investigates the impact of different oxygen concentrations (99.99%, 10%, and 5%) on (PM) oxidation when using silver catalysts supported on CeO2, ZnO, TiO2, and Al2O3. The synthesized catalysts were characterized using XRD, SEM, SEMEDX, and H2-TPR techniques, and the PM oxidation activity was evaluated using TGA. The results demonstrated that different oxygen concentrations had little effect on light VOCs oxidation compared to no catalyst or the same catalyst. However, heavy VOCs and soot combustion, which require a higher oxygen concentration, significantly reduce combustion performance when the oxygen concentration decreases

The Influence of Direct Non-Thermal Plasma Treatment on Soot Characteristics under Low Exhaust Gas Temperature

This study aimed to assess the effectiveness of nonthermal plasma (NTP) technology utilizing a dielectric barrier discharge (DBD) reactor, both with and without exhaust gas recirculation (EGR), in reducing soot particles and their impact on nitrogen oxides (NOx). The experiment involved maintaining a constant flue gas flow rate of 10 l/min, employing high voltage values of 0, 6, and 10 kV, fixed frequency of 500 Hz and setting the various IMEP of 5, 6, and 7 bar and the engine speed at 2,000 rpm. The findings demonstrated that NTP was successful in removing NOx by approximately 16.84% and 17.01%, achieving particle matter (PM) removal efficiencies of around 60.79% and 81.13%, and effectively reducing activation energy by approximately 18.34% and 31.5% (with and without EGR, respectively) at a high voltage of 10 kV. These results highlight the potential of NTP technology in mitigating emissions and reducing the environmental impact associated with diesel engines

Promotion of the NO-to-NO₂ Conversion of a Biofueled Diesel Engine with Nonthermal Plasma-Assisted Low-Temperature Soot Incineration of a Diesel Particulate Filter

High-concentration biodiesel-diesel fuel blends are an alternative fuel widely used for compression ignition engines. However, commercial diesel engines are not designed and set up for high-concentration biodiesel-diesel fuel blends. Hence, the aim of this research was to investigate the nonthermal plasma (NTP) activities during an NOx reduction and the soot characteristics on an unmodified diesel engine (Euro V) that is fueled with various biodiesel blends with diesel under a low exhaust gas temperature (<250 °C). The experiment found that the soot composition of biodiesel fuel produces lower levels of soot when compared with diesel, in terms of both number and mass. In addition, the activation energies (Ea) of carbon oxidation under an oxygen atmosphere were found to be approximately 154.57–173.64 kJ/mol