Yuichi Fujioka

Pure silica CHA type zeolite for CO2 separation using pressure swing adsorption at high pressure

Pure silica CHA type zeolite (Si-CHA) was used in a high pressure swing adsorption for CO2 separation in the presence of water. The effective CO2 adsorption capacity was much higher than that of zeolite 13X, and was not influenced by coexisting water. The breakthrough curve gave an effective CO2 adsorption capacity of 3.1 mol kg−1 and CO2–N2 selectivity of >31.

Investigation of Transition Metal Oxide Catalysts for Diesel PM Removal Under Plasma Discharge Conditions

Seven different transition metal oxides (TiO2, ZnO, V2O5, Fe2O3, Co3O4, MnO2, and CuO) have been investi- gated for oxidation of diesel particulate matter (PM) under plasma discharge conditions. The experiments were carried out by measuring PM oxidation rates over each catalyst using a batch-type dielectric barrier discharge reactor. It was found that TiO2, ZnO, V2O5, and Fe2O3 can promote PM oxidation, among which Fe2O3 is a most desirable catalyst for PM oxi- dative removal as PM oxidation rate promoted by Fe2O3 is highest under plasma discharge conditions. The mechanism of PM catalytic oxidation over the metal oxides has been suggested to follow the redox catalytic cycles from the correlation of the catalytic oxidation rates with the formation enthalpies per oxygen atom of the catalysts. O atoms generated by plasma discharges may play an important role in promoting the re-oxidation of the catalysts. The highest catalytic activity for the PM oxidation with Fe2O3 has been suggested to be due to the balance between the reduction rate and the re- oxidation rate within the redox catalytic cycles.

Energy contribution in a DBD reactor

Summary form only given. Dielectric barrier discharge (DBD) reactors are widely used for such as ozone generation and pollution controls. The energy injected into a DBD reactor is used expectantly to generate ions, energized electrons, radicals and excited atoms/molecules to yield a non-thermal plasma. In such a plasma, generation or decomposition of chemicals via chemical reactions occurs. The evaluation of energy contribution to the generation of ions, energized electrons, radicals and excited atoms/molecules is of great interests in order to improve energy efficiency for the generation or decomposition of chemicals. In this study, experimental evaluation of the energy contribution to ozone generation has been carried out using a DBD reactor, a pulse power supply, a discharge voltage/current waveform measurement system, and an ozone monitor. Results will be presented.

Application of a Dielectric Barrier Discharge Reactor for Diesel PM Removal

An uneven DBD reactor driven by a pulse power supply for diesel particulate matter (PM) removal has been characterized using a diesel engine. The relations between energy injection, PM removal, space velocity and pressure loss are given.