The present disclosure relates to a hydrogen gas production method including: a first step of generating a mixed gas containing hydrogen and carbon dioxide from a hydrogen storage agent by dehydrogenation reaction using a catalyst in a reactor; a second step of purifying the generated mixed gas to acquire a gas having a high hydrogen concentration; a third step of separating a solution in the reactor into a solution enriched with the catalyst and a permeate using a separation membrane unit; and a fourth step of supplying the solution enriched with the catalyst to the reactor for reusing in the first step.

The present invention relates to novel fused imidazo pyrazole derivatives of formula (I), and formula (II), and methods for preparation thereof, in the presence of a chitosan-Al.sub.2O.sub.3 nanocomposite film. The invention also relates to pharmaceutical compositions comprising compounds of the invention as active ingredients as well as the use of compounds of the invention for antimicrobial action.

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A method for aromatization of light alkanes, comprising: subjecting the light alkanes to dehydroaromatization reaction in the presence of aromatization catalysts including carriers and metal active components supported on the carriers, the metal active components include platinum, the carriers include zeolites and binders, and at least 80 wt. % of the metal active components are distributed on the zeolites. The method of the present disclosure may increase yield of the target product—aromatic hydrocarbons, and the regenerated catalyst can still maintain high catalytic performance. In addition, the method of the present disclosure can meet the requirements of industrial applications.

The present invention addresses to a process for the production of alkyl-naphthenics for use as diesel and/or aviation kerosene (JET A-1), whose process involves the alkylation of olefins with monoaromatics and subsequent hydrogenation to alkyl-naphthenics. The process and catalysts of the present invention allow the regeneration of the acidic catalyst with a hydrogenating function and full recovery of its activity with hydrogen hot stripping. The catalyst is used for the formation of intermediate alkyl-aromatics and can also be used in the subsequent hydrogenation to alkyl-naphthenics.

The present disclosure is to provide a catalyst for olefin production which is eco-friendly and has excellent conversion rates and selectivity and a preparation method thereof, and the catalyst for olefin production according to the present disclosure is one in which cobalt and zinc are supported with alumina. Particularly, the catalyst according to the present disclosure uses an amount of platinum that is about 400 times smaller than that of the conventional catalysts, and has high conversion rates and selectivity under conditions in which continuous reaction-regeneration process is possible without an additional hydrogen reduction process.

A regeneration device, a device for preparing low-carbon olefins, and a use thereof are provided. The regeneration device includes a first regenerator and a second regenerator; a first activation zone of the first regenerator is connected to the second regenerator through a pipeline, such that a catalyst in the first activation zone is able to be delivered to the second regenerator; and the second regenerator is connected to a gas-solid separation zone of the first regenerator through a pipeline, such that a catalyst in the second regenerator is able to be delivered to the gas-solid separation zone. The regeneration device can adjust the coke content, coke content distribution, and coke species in a dimethyl ether/methanol to olefins (DMTO) catalyst to control an operation window of the DMTO catalyst, which improves the selectivity for low-carbon olefins and the atomic economy of a methanol-to-olefins (MTO) technology.

Realized is a method for restoring the activity of a catalyst for producing a carbonate ester by a simple technique with no use of a complicated step such as calcining or the like to allow the catalyst to be reusable, and a method for producing a carbonate ester at a high yield by use of the catalyst thus regenerated. The above-described problem has been solved by a method for regenerating a catalyst containing CeO.sub.2, the catalyst being usable for a carbonate ester generation reaction of generating a carbonate ester from carbon dioxide and an alcohol, the method comprising (a) a separation step of separating the catalyst as a crude catalyst from a reaction solution of carbon dioxide and the alcohol; and (b) a catalyst processing step of washing the crude catalyst with a washing alcohol to provide a purified catalyst.

The present invention discloses a nickel/titanium oxide-silicon oxide catalyst for synthesizing terpinene-4-ol as well as a preparation method and method of synthesizing terpinene-4-ol using the same. The preparation method includes the steps of catalyst preparation, terpinene-4-ol synthesis and the like are disclosed in the present invention. The preparation method includes the following steps: firstly, preparing a mixed colloid of TiO.sub.2 and SiO.sub.2 by using a sol-gel method, and then centrifuging, washing, drying and roasting is performed to prepare a TiO.sub.2—SiO.sub.2 binary oxide; then, preparing Ni/TiO2-SiO2 by dipping in a nickel nitrate solution, and preparing a supported catalyst by drying and roasting; and finally, adopting a terpinolene-4, 8-epoxide a raw material, carrying out isomerization under the dual catalytic action of TiO2-SiO2 and Ni of the supported catalyst, and carrying out hydrogenation to prepare terpinene-4-ol. The preparation method can combine isomerization and hydrogenation reaction on the same catalyst, has good selectivity on terpinene-4-ol, and is simple to operate and high in product yield.

The present disclosure provides a preparing method for 5-alkoxymethylfurfural, including steps of (a) preparing fructose, (b) mixing the fructose, an organic acid catalyst, and an organic solvent, thereby preparing mixing solution, and (c) heating the mixing solution, thereby preparing 5-alkoxymethylfurfural. Therefore, 5-alkoxymethylfurfural may be effectively prepared without by-products from fructose.

Here disclosed is a composite catalyst for methane cracking and a method of producing the composite catalyst. The composite catalyst includes a substrate formed of metal oxide, and one or more catalytic transition metals solubilized in the metal oxide, wherein the metal oxide includes a metal which differs from the one or more catalytic transition metals, wherein the metal oxide forms a matrix which the one or more catalytic transition metals are solubilized in to render transition metal ions from the one or more catalytic transition metals, wherein the transition metal ions under a reducing atmosphere diffuse to reside as transition metal nanoparticles at a surface of the substrate and the transition metal nanoparticles under an oxidizing atmosphere diffuse away from the surface to reside as transition metal ions in the metal oxide, and wherein the transition metal nanoparticles at the surface induce carbon from the methane cracking to deposit on the transition metal nanoparticles and have the carbon deposited grow away from the substrate.