The invention discloses a visible light responsive tricobalt tetraoxide dodecahedron/carbon nitride nanosheet composite and an application thereof in exhaust gas treatment. The preparation method of the composite comprises the following steps: with urea as a precursor, carrying out twice calcination to obtain carbon nitride nanosheet; dispersing the carbon nitride nanosheet into methanol, sequentially adding cobalt nitrate hexahydrate and 2-methylimidazole, and carrying out a reaction to obtain a carbon nitride nanosheet composite; and calcining the carbon nitride nanosheet composite in an air atmosphere at a low temperature to obtain the tricobalt tetraoxide dodecahedron/carbon nitride nanosheet composite. The in-situ growth synthesis method can ensure that the tricobalt tetraoxide obtained by follow-up calcination is uniformly coated on the carbon nitride nanosheet to improve the catalytic performance; the low temperature calcination ensures that the carbon nitride can maintain its wrinkle state and chemical structure during the calcination process.

The present disclosure relates to the preparation of pyridine derivatives, such as -picoline or -parvoline, and catalysts useful for the selective preparation of such pyridine derivatives. Particularly, the present disclosure relates to the selective preparation of certain pyridine derivative using dealuminated zeolite catalysts.

JMZ-5, an aluminosilicate having an SZR framework type and a sea-urchin type morphology is described. A calcined product, JMZ-5C, formed from JMZ-5 is also described. JMZ-6, an aluminosilicate having an SZR framework type and a needle, aggregate morphology is described. A calcined product, JMZ-6C, formed from JMZ-6 is also described. Methods of preparing these zeolites and their metal-containing calcined counterparts are described along with methods of using these zeolites and their metal containing calcined counterparts in treating exhaust gases.

The invention relates to a catalyst and catalyst layer and process for preparing dimethyl ether from synthesis gas or methanol as well as the use of the catalyst or catalyst layer in this process.

An object of the present invention is to provide means for improving the hydrogen generation properties of a hydrogen-producing catalyst. A hydrogen-producing catalyst according to one aspect of the present invention comprises Rh and a composite containing Al, Ce, and Zr. When a ratio of the number of Al atoms to the number of Ce atoms (Al/Ce) in the composite measured by X-ray fluorescence (XRF) analysis is R.sub.I and a ratio of the number of Al atoms to the number of Ce atoms (Al/Ce,) in the composite measured by an Xray photoelectron spectroscopy (XPS) method is R.sub.2, a value of R.sub.2-R.sub.1 is greater than 2.25 and less than 5.92.

A mesoporous metal doped cerium oxide catalyst is provided. The catalyst can contain nanotextured cerium oxide (CeO.sub.2) which can be utilized for hydrogen production or reformate gas purification in a water gas shift reaction. The catalyst may be advantageously used to remove CO from a gas containing CO. The catalyst may also be incorporated into a fuel processor.

The present invention disclosed preparation method of a visible-light-driven CC@SnS.sub.2/SnO.sub.2 composite catalyst, and application thereof, comprising the following steps: preparing CC@SnS.sub.2 composite material in a solvent by using SnCl.sub.4.5H.sub.2O and C.sub.2H.sub.5NS as raw materials and carbon fiber cloth as a supporting material; calcining said CC@SnS.sub.2 composite material to obtain the visible-light-driven CC@SnS.sub.2/SnO.sub.2 composite catalyst. The present invention overcomes defects of the traditional methods of treating chromium-containing wastewater, including chemical precipitation, adsorption, ion exchange resin and electrolysis, and the photocatalytic technology can make full use of solar light source or artificial light source without adding adsorbent or reducing agent. In this case, the use of semiconductor photocatalyst to convert hexavalent chromium in chromium wastewater into less toxic and easily precipitated trivalent chromium greatly reduces the cost and energy consumption.

Provided is a silica titania composite aerogel particle including a base particle in which an element ratio Si/Ti of silicon to titanium is greater than 0 and equal to or lower than 6. A BET specific surface area of the silica titania composite particle is within a range of 200 m.sup.2/g to 1200 m.sup.2/g, and the silica titania composite particle has absorption at wavelengths of 450 nm and 750 nm.

Provided is catalyst material useful for the selective catalytic reduction of NOx in lean burn exhaust gas, wherein the catalyst material is a hydrothermally stable, low SAR aluminosilicate zeolite loaded with a synergistic combination of one or more transition metals, such as copper, and one or more alkali or alkaline earth metals, such as calcium or potassium.

Catalysts, catalytic systems and related synthetic methods for in situ production of H.sub.2O.sub.2 and use thereof in reaction with oxidizable substrates.