The present invention discloses a molecular sieve and its preparation method. The molecular sieve has micromorphology in a football shape and consists of molecular sieve framework and active elements. The molecular sieve framework comprises silicon element and aluminum element; the active elements comprise copper element and rare earth elements. The rare earth elements are one or more selected from the group consisting of La, Ce, Pr, Nd, Pm, Sm, Eu, Sc and Y. The mass ratio of the silicon element to the aluminum element is 3-9:1. The content of the copper element in the molecular sieve is 1.5-3.2 wt %. The mass of rare earth elements is 50 ppm-2 wt % of the molecular sieve framework. The mass of the silicon element is calculated by silicon dioxide, the mass of aluminum element is calculated by aluminum oxide, the mass of copper element is calculated by copper oxides, and the mass of rare earth elements is calculated by rare earth oxides. The molecular sieve has a high catalytic activity in a temperature range of 175-550° C. and a good resistance to hydrothermal aging.

A method for enhancing degradation of ester volatile organic compounds with a cerium oxide supported palladium single atom catalyst under low-temperature microwave comprises the steps of firstly preparing a single atom catalyst Pd/CeO.sub.2, adding the catalyst Pd/CeO.sub.2 into a reaction cavity, initiating microwave radiation to enhance the catalysis reaction, and quickly introducing an ester compound with a concentration of 50˜5000 mg/m.sup.3 and a space velocity of 2000˜100000 h.sup.−1 into the reaction cavity from a vapor phase sampling port to react when the reaction temperature is 10˜80° C. A catalyst packed column is provided in the reaction cavity, the vapor phase sampling port is defined at the bottom of the reaction cavity, and an exhaust port is defined at the top of the cavity. The microwave method can enhance and activate active sites, prevent the aging of active sites, and enable the chemical reaction rate to be increased by more than 17.9%.

Methods of making an iron based catalyst using microwave hydrothermal synthesis are provided. The methods include dissolving iron(III) nitrate, Fe(NO.sub.3).sub.3, in an organic solvent to form a solution. Once dissolved, the methods include a step of neutralizing the solution with an alkaline mineralizing agent to obtain a precipitate. The solution with the precipitate is then subjected to microwave radiation to cause a temperature gradient and a hydrothermal crystallization process to form a synthesized product. The synthesized product is subsequently separated from the mineralizing agent. The method includes washing and drying the synthesized product to obtain particles of sodium iron oxide (NaFeO.sub.2) catalyst that can be used as a composition for a passive NO.sub.x adsorber. A two-stage NO.sub.x abatement device for removal of NO.sub.x from an exhaust gas stream during a cold start operation of an internal combustion engine is also provided.

Disclosed is the synthesis of novel supported metal catalytic materials for electromagnetic radiation absorption and chemical catalysis especially in the presence of plasma used in the conversion of nitrogen from air and hydrogen from water to useful products such as nitric acid, hydrogen, ammonia and fertilizers. These materials can also generate plasma when subjected to microwave irradiation thus form the basis of catalytic plasma reactors. They can be used in chemical looping reactions because plasma generation under microwave irradiation in air results in the reduction of catalyst oxides and oxidation of nitrogen.

A method of making a titanium dioxide nanowire array includes contacting a substrate with a solvent comprising a titanium (III) precursor, an acid, and an oxidant while microwave heating the solvent, thereby forming a hydrogen titanate H2Ti2O5.H2O nanowire array. The hydrogen titanate nanowire array is annealed to form a titanium dioxide nanowire array. The substrate is seeded with titanium dioxide before starting the hydrothermal synthesis of the hydrogen titanate nanowire array. The titanium dioxide nanowire array is loaded with a platinum group metal to form an exhaust gas catalyst. The titanium dioxide nanowire array can be used to catalyze oxidation of combustion exhaust.

A method for preparing a silicate/carbon composite from attapulgite, and use of the silicate/carbon composite are disclosed. The preparation method includes: (1) with attapulgite as a raw material, preparing SiO.sub.2 with a special structure; (2) dispersing the prepared SiO.sub.2 in water to obtain a suspension, and subjecting the suspension to ultrasonic dispersion; dissolving a metal nitrate in the suspension, adding NH.sub.4Cl, and adding ammonia water dropwise to the suspension; and adding sucrose to obtain a suspension; (3) subjecting the suspension to microwave hydrothermal reaction; after the reaction is completed, centrifuging a resulting system; and separating a resulting solid; and (4) subjecting the solid to high-temperature calcination in a muffle furnace, and grinding a resulting product to obtain the silicate/carbon composite, which can be used in photocatalytic ammonia synthesis.

Disclosed apparatuses, systems, and materials relate to the disassociation of feedstock species (such as those in gaseous form) into constituent components, and may include an energy generator configured to provide a microwave energy. A first chamber defines a first volume and is configured to guide the microwave energy along the first chamber as a sinusoidal wave having an energy maxima at a point along the first chamber. A second chamber contains a plasma plume and is positioned substantially proximal to the first chamber, and is configured to enable propagation of the microwave energy through the first chamber and the second chamber such that the microwave energy demonstrates, at a radial center of the second chamber, a coaxial energy maxima configured to ignite the plasma plume contained in the second chamber. Carbon-containing materials may be formed by controlling flow parameters of the feedstock species into the first or second chamber.

A preparation method and use of a novel pure inorganic solid silicon-based sulfonic acid and/or phosphoric acid catalytic material are disclosed. The surface hydroxyl-rich metasilicic acid is used as the raw material, and by using a sulfonating reagent and/or phosphoric acid, the sulfonic acid group and/or the phosphoric acid group are bonded to the inorganic silicon material by chemical bonding to obtain a pure inorganic solid silicon-based sulfonic acid and/or phosphoric acid catalytic material. The catalytic material can be widely used in many acid-catalyzed organic reactions such as isomerization, esterification, alkylation, hydroamination of olefins, condensation, nitration, etherification, multi-component reactions and oxidation reactions. The inorganic solid silicon-based sulfonic acid and/or phosphoric acid catalytic material of the present invention has the advantages of high acid amount, high activity, good hydrothermal stability, no swelling, simple preparation, low cost, no pollution, no corrosion, easy separation and reusability.

Methods of preparing oligomers of an olefin are provided. The methods can include providing an alkylaluminum compound and irradiating the alkylaluminum compound with microwave radiation to provide an irradiated alkylaluminum compound. The methods can further include mixing the irradiated alkylaluminum compound with a chromium compound, a pyrrole compound, and a zinc compound to provide a catalyst composition. The methods can further include contacting an olefin with the composition to form oligomers of the olefin. The olefin can include ethylene, and the oligomers of the olefin can include 1-hexene.

A system for producing carbonaceous materials is disclosed that includes an energy source configured to emit microwave energy and a plasma reactor coupled to receive the microwave energy and configured to produce plasma in response to exposure of one or more process gases to the microwave energy. In some instances, the plasma reactor includes a first chamber having a rectangular cross-section and configured to receive the microwave energy from the energy source as sinusoidal waveform, a second chamber having a cylindrical cross-section and configured to receive microwave energy from the first chamber as a radial waveform having an energy maxima at a radial center of the cylindrical cross-section, the second chamber including an opening to receive one or more process gases and configured to ignite a plasma plume, and a gas-solid separator configured to separate solid materials from the plasma plume.