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A significant microwave selective effect on oxygen inhibition removal was found for NO decomposition through microwave catalysis over BaMn(x)Mg(1-x)O3 catalysts. Especially, the NO conversion and N2 selectivity were up to 99.8% and 99.9%, respectively for the BaMn(0.9)Mg(0.1)O3 catalyst even with the coexistence of 10% oxygen and low temperature of 250 °C.

The use of microwave (MW) irradiation to increase the rate of chemical reactions has attracted much attention recently in nearly all fields of chemistry due to substantial enhancements in reaction rates. However, the intrinsic nature of the effects of MW irradiation on chemical reactions remains unclear. Herein, the highly effective conversion of NO and decomposition of H2S via MW catalysis were investigated. The temperature was decreased by several hundred degrees centigrade. Moreover, the apparent activation energy (Ea’) decreased substantially under MW irradiation. Importantly, for the first time, a model of the interactions between microwave electromagnetic waves and molecules is proposed to elucidate the intrinsic reason for the reduction in the Ea’ under MW irradiation, and a formula for the quantitative estimation of the decrease in the Ea’ was determined. MW irradiation energy was partially transformed to reduce the Ea’, and MW irradiation is a new type of power energy for speeding up chemical reactions. The effect of MW irradiation on chemical reactions was determined. Our findings challenge both the classical view of MW irradiation as only a heating method and the controversial MW non-thermal effect and open a promising avenue for the development of novel MW catalytic reaction technology.

Preparation of catalystsCu-ZSM-5 was prepared by the ion-exchange method. H-ZSM-5 (Si/ Al = 50 supplied by Nankai University, China) was exchanged with an aqueous solution of Cu(AC) 2 (0.01 mol L À1 , AR grade, Shenyang Agent Company, China) according to the ratio of H-ZSM-5 and the aqueous solution, which was 15 g L À1 . The solution was adjusted the pH to 7 by the addition of ammonia and stirred for 12 h at 50 8C. After it was collected by filtration, the sample was washed with deionized water and dried at 100 8C for 10 h and calcined at 500 8C for 6 h. Ion exchange was performed twice to obtain a final Cu-ZSM-5 zeolite catalyst that contained 5 wt % Cu. MeO x -Cu-ZSM-5 (Me = Mn, Ni) catalysts were prepared by a mechanical mixing method. Ni 2 O 3 (AR grade, Shanghai Qiangshun Chemical Reagent Co., Ltd., China) or MnO 2 (AR grade, Taijin Fengchuan Chemical Reagent Co., Ltd., China) was added to Cu-ZSM-5, and the mixture was ground and mixed uniformly in a mortar. Catalyst characterizationXRD patterns of the samples were obtained by using a Rigaku D/ max-II/2500 X-ray powder diffractometer. CuK a radiation was employed, and the working voltage and current were 40 kV and 250 mA, respectively. FTIR spectra were recorded by using a Nicolet 380 spectrometer from 4000 to 400 cm À1 , and the KBr pellet technique was used.

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Suspension, colloidal, and emulsion flow in rocks with particle size-exclusion may have a strong effect on the reservoir and on the well behavior during fines migration and production, drillingfluid invasion into oil-or gas-bearing formations, or injection of seawater or produced water. The stochastic microscale equations for size-exclusion colloidal transport in porous media (PM) are derived. The proposed model includes the following new features: It accounts for the accessible flux in the expression for capture rate, it accounts for the increase of inlet concentration caused by the injected particles entering only the accessible area, and it accounts for the dilution of effluent accessible flux in the overall flux of the produced suspension. Two sets of laboratory tests on short-term injection of monosized suspensions have been carried out in engineered PM. The treatment of the laboratory data for short-term continuous-suspension injection shows good agreement with the modeling results. The proposed model shows a better fit to the experimental data than the previous population-balance model for suspension transport in PM, which validates the proposed modified model. Microscale Modeling for Particle Straining The stochastic modeling of suspension flow in PM, accounting for straining particle capture, is established in this section. The medium is represented by the model of triangular parallel capillaries alternated with mixing chambers. The analytical model for lowretention filtration is derived, and the steady-state solution is obtained.

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