In order to design a compact urea selective catalytic reduction system, numerical simulation was conducted by computational fluid dynamics tool. A swirl type static mixer and mixing chamber were considered as units in the system. It had great influence on flow characteristics decomposition into ammonia. The caused recirculation high level of turbulence intensity, increased residence time urea- water-solution injected. Because those effects, reaction rates enhanced region. When combined, it...

Methanation of CO2 using H2 obtained by renewable energy sources has been gaining attention as one the promising options for utilizing captured and surplus power when intermittent such solar wind are used. Herein, kinetics methanation over Ni/ZrO2 was studied a tubular quartz reactor at 0.9 MPa. The Sabatier reaction (CO2 + 4H2 = CH4 2H2O, ΔHr298K – 165 kJ mol–1) carried out under stoichiometric gas feeding (CO2/H2 1/4 v/v to CH4/H2O 1/2 v/v), its rate determined. exothermic nature extremely...

A numerical simulation for urea decomposition into ammonia with static mixers was performed marine selective catalytic reduction.Three types of mixer were considered to improve conversion rate.The effect each such as pressure drop, particle residence time, and uniform distribution water solution investigated using three dimensional CFD code.Using regardless a type improved decomposition.Engine performance could be affected by high drop caused mixer.Therefore, the proper should chosen in...

Inherent metallic species retained by coal char or coke, such as Na and Ca, behave catalysts in gasification. The char/coke normally contains inherent SiO2, which can react with the to form silicates, resulting catalyst deactivation over range of pyrolysis, carbonization gasification, thereby reducing reactivity. present authors simulated experimentally blending a Victorian lignite briquetting SiO2/lignite blend, carbonizing briquette, then gasifying coke CO2. kinetic analysis gasification...

Abstract The Sabatier process is promising for carbon dioxide utilization and energy storage. However, the serious problem that limits more comprehensive industrial applications catalyst deactivation due to temperature runaway phenomenon. inert particle dilution approach, including mixing method layered applied solve this problem. Based on lattice kinetic scheme‐lattice Boltzmann (LKS‐LBM), effects of three parameters in bed structure reconstructed by discrete element (DEM) distribution...

This work presents the formation of butyl levulinate, a potential fuel additive, and an excellent renewable chemical obtained by butanolysis furfuryl alcohol (FAL) over solid acid catalyst. The reaction is strong function acidity for which tungstated zirconia (WO3-ZrO2), robust catalyst, sulfonated carbon catalyst were employed to produce high yields levulinate targeting lower initial molar ratio butanol FAL. A maximum 28 mol% yield was with Easily prepared at temperatures facilitated...

Development of a kinetic model for CO2 methanation over commercial nickel catalyst was performed to consider pathways conversion via Sabatier and RWGS reactions. H2/CO2 ratio in the feed gas composition varied at stoichiometry reaction assuming fictitious 0 0.7. Non-stochiometric feeding addition product gases, i.e., methane steam, were also considered examine orders inhibition effects. The tests carried out 300–350 °C 0.1–0.9 MPa. GHSV corresponded 37,494 h−1. stable activity achieved by...

Kinetics of thermal decomposition benzene on lignite-derived char was investigated at 900 °C by applying a new method to continuously monitor the surface activity. Benzene vapor forced pass through micro fixed bed with residence time as short 7.6 ms, and then detected flame-ionization detector. Results showed presence two different types surfaces; consumptive Type I non-consumptive (sustainable) II surface. partially CO2-gasified had an capacity carbon deposit from over 20 wt%-char initial...

Kinetic analysis of CO2 gasification by thermogravimetry was examined employing chars from a Victorian lignite. The char the rigorously acid-washed lignite extremely slow. More than 600 min required for complete as result near absence inherent alkali and alkaline earth metallic (AAEM) species. It nonetheless necessary to strictly choose following conditions eliminating mass transfer effect: an initial <1.3 mg, particle size <125 μm, total gas flow rate ≥1000 mL standard temperature pressure...

The current state of lignin has been characterized by these three: (1) as one the main components in lignocellulosic biomass with an abundant amount; (2) not be taken seriously but treated a waste product; (3) underutilized due to complex and stubborn structure. However, can rich source for hydrocarbons aromatic compounds when gives appropriate utilization. In this work, we have studied hydrotreatment alkaline (AL) under relatively mild conditions further investigated characterization...

Researchers have thoroughly studied coal pyrolysis over a long period, while the analysis of volatile evolution and chemical structural changes solid char were carried out individually in most studies. In this work, we quantified reactions to explain different physical phenomena, such as softening caking properties, exhibited by ranks coals during pyrolysis. Four typical carbonaceous feedstocks (bituminous, sub-bituminous, lignite coals, biomass) selected test samples. The authors analyzed...

The present study further develops an approach in predicting reactions undergone by coal volatiles a reducing section (reductor) of air-blown two-stage entrained flow gasifier toward designing better gasification process. A detailed chemical kinetic model was first applied to simulate complex molecular mixture the evolved due rapid pyrolysis fed into reductor. composition determined based on pyrolysis-gas chromatography experiments, where 22 compounds including inorganic gases (H2, H2O, CO...

Abstract CO 2 methanation, which converts and hydrogen into methane as fuel, is one of the promising candidates for development utilization technologies. Recently, a highly active catalyst made Ni/ZrO methanation has been developed, currently investigated potential use in high‐performance reactor. However, design reactor must be carried out carefully, since this reaction exothermic, may cause runaway deterioration catalysts. For problem, mathematical model that can predict behavior inside...