The devices, systems and techniques disclosed in this patent document include photocatalytic filter devices and can be used to provide a method for manufacturing a photocatalytic filter with improved adhesion. In addition, the present disclosure of this patent document includes technology to provide a method for reactivating a photocatalytic filter. Using the disclosed techniques, even if a photocatalytic filter is contaminated, the contaminated photocatalytic filter is easily reactivated while maintaining improved adhesion.

A method for in-situ generation of nanoflower-like manganese dioxide catalyst on filter material is provided. The method comprises: immersing a filter material in a solution containing sodium lauryl sulfate and nitric acid; first modifying the surface of the filter material by using the sodium lauryl sulfate so that a charge layer is wound around the surface of the filter material and tightly absorbs H.sup.+ in an acid solution; and then adding potassium permanganate as an oxidant to react with H.sup.30 on the surface of the filter material to generate nano flower-like manganese dioxide in situ on the surface of the filter material, so as to obtain a composite filter material having a denitration function.

The present invention relates to a carbon nanotube composition including entangled-type carbon nanotubes and bundle-type carbon nanotubes, wherein the carbon nanotube composition has a specific surface area of 190 m.sup.2/g to 240 m.sup.2/g and a ratio of specific surface area to bulk density of 0.1 to 5.29.

A layered catalyst structure for purifying an exhaust gas stream includes a catalyst support and a palladium catalyst layer including an atomic dispersion of palladium ions electrostatically adsorbed onto an exterior surface of the catalyst support. The catalyst support includes an alumina substrate, a first ceria layer disposed on and extending substantially continuously over the alumina substrate, and a second colloidal ceria layer formed directly on the first ceria layer over the alumina substrate. The palladium catalyst layer is formed on the exterior surface of the catalyst support by applying a palladium-containing precursor solution to the exterior surface of the catalyst support and then heating the catalyst support and the palladium-containing precursor solution. The palladium-containing precursor solution includes a positively charged palladium complex in an aqueous medium and has a pH greater than a point of zero charge of the second colloidal ceria layer.

Provided is a preparation method of a coating material. The method includes: using an aluminum salt and a silicon source as precursors; and performing hydrothermal crystallization and calcination treatments successively under an action of a template agent to obtain the coating material, wherein the template agent is used to cause the coating material to form a porous spherical structure. In the embodiments of the present disclosure, the preparation process of the coating material is simple and the cost is low, and the specific surface area of the prepared coating material is large.

A composite solid base catalyst, a manufacturing method thereof and a manufacturing method of glycidol are provided. The composite solid base catalyst includes an aluminum carrier and a plurality of calcium particles. The plurality of calcium particles are supported by the aluminum carrier. Beta basic sites of the composite solid base catalyst are 0.58 mmol/g-3.89 mmol/g.

The present invention provides a catalyst structure having a core-shell structure comprising a core comprising a metal and a shell formed on the core, wherein the shell comprises a metal hydroxide crystal or a metal oxide crystal formed uniformly in shape and size perpendicular to the surface of the metal, wherein the metal hydroxide crystal or the metal oxide crystal have a 2D structure or a 1D structure, and preparation method thereof.

The present invention relates to a catalyst and a method for preparation of that catalyst for the selective hydrogenation of diolefins present in gasoline streams along with the shifting of lighter sulfur compounds in the feed stock to heavier sulfur compound by the reaction with olefinic compounds.

A non-stoichiometric nanocomposite coating and method of making and using the coating. The non-stoichiometric nanocomposite coating is disposed on a base material, such as a metal or ceramic; and the nanocomposite consists essentially of a matrix of an alloy selected from the group of Cu, Ni, Pd, Pt and Re which are catalytically active for cracking of carbon bonds in oils and greases and a grain structure selected from the group of borides, carbides and nitrides.

Carbon nanofiber doped alumina (Al—CNF) supported MoCo catalysts in hydrodesulfurization (HDS), and/or boron doping, e.g., up to 5 wt % of total catalyst weight, can improve catalytic efficiency. Al—CNF-supported MoCo catalysts, (Al—CNF—MoCo), can reduce the sulfur concentration in fuel, esp. liquid fuel, to below the required limit in a 6 h reaction time. Thus, Al—CNF—MoCo has a higher catalytic activity than Al—MoCo, which may be explained by higher mesoporous surface area and better dispersion of MoCo metals on the AlCNF support relative to alumina support. The BET surface area of Al—MoCo may be 75% less than Al—CNF—MoCo, e.g., 166 vs. 200 m.sup.2/g. SEM images indicate that the catalyst nanoparticles can be evenly distributed on the surface of the CNF. The surface area of the AlMoCoB5% may be 206 m.sup.2/g, which is higher than AlMoCoB0% and AlMoCoB2%, and AlMoCoB5% has the highest HDS activity, removing more than 98% sulfur and below allowed levels.