The present disclosure provides an active material comprising a mixed metal oxide in a hydrotalcite derived rocksalt structure, a processes to convert paraffins to corresponding olefins and or heavier hydrocarbons using the active material, and a method of preparing the active material.

The present invention relates to a method for preparing carbon nanotubes, the method including: preparing a support including AlO(OH) by primary heat treatment of Al(OH).sub.3; preparing an active carrier by supporting a mixture including a main catalyst precursor and a cocatalyst precursor on the support; drying the active carrier through multi-stage drying including vacuum drying; preparing a supported catalyst by secondary heat treatment of the dried active support; and preparing carbon nanotubes in the presence of the supported catalyst, and the carbon nanotubes prepared by the method as described above can remarkably improve conductivity.

The present invention relates to a method for preparing carbon nanotubes, the method including: preparing a support including AlO(OH) by primary heat treatment of Al(OH).sub.3; preparing an active carrier by supporting a mixture including a main catalyst precursor and a cocatalyst precursor on the support; drying the active carrier through multi-stage drying including vacuum drying; preparing a supported catalyst by secondary heat treatment of the dried active support; and preparing carbon nanotubes in the presence of the supported catalyst, and the carbon nanotubes prepared by the method as described above can remarkably improve conductivity.

The present invention provides a catalyst comprising a transition metal, an inorganic support, a zeolite, and a layered double hydroxide. Using of the catalyst according to the present invention in an olefin production process exhibits high activity and high selectivity with decreased deactivation rate, therefore longer reaction cycle can be performed and catalyst life is prolonged.

The present invention provides a catalyst comprising a transition metal, an inorganic support, a zeolite, and a layered double hydroxide. Using of the catalyst according to the present invention in an olefin production process exhibits high activity and high selectivity with decreased deactivation rate, therefore longer reaction cycle can be performed and catalyst life is prolonged.

The present invention belongs to the flue gas desulfuration field. Specifically, the present invention relates to a supported solid-phase catalyst for oxidizing the by-product magnesium sulfite in a magnesium desulfuration process, and to preparation method and use thereof. The catalyst uses an activated carbon particle as a support, and cobalt nitrate, manganese nitrate, copper nitrate and ferrous nitrate as catalytically active components. The preparation method is as follows: mixing the pre-treated activated carbon support with the catalytically active components, followed by oscillating, standing under microwave irradiation, filtrating, drying, baking, so as to obtain the supported solid-phase catalyst. Raw materials of the present invention are inexpensive and easily available; the preparation process is simple; the catalyst has prominent catalytic effect and can be widely used in the magnesium desulfuration process in medium-sized and small-sized boilers of 75t or more to improve the recovery rate of the desulfuration by-product and reduce energy consumption of the oxidation system; the catalyst has a low amount of catalytically active components and causes low residue in the solution and hence no secondary pollution problem, and has a high generalization value.

The present invention belongs to the flue gas desulfuration field. Specifically, the present invention relates to a supported solid-phase catalyst for oxidizing the by-product magnesium sulfite in a magnesium desulfuration process, and to preparation method and use thereof. The catalyst uses an activated carbon particle as a support, and cobalt nitrate, manganese nitrate, copper nitrate and ferrous nitrate as catalytically active components. The preparation method is as follows: mixing the pre-treated activated carbon support with the catalytically active components, followed by oscillating, standing under microwave irradiation, filtrating, drying, baking, so as to obtain the supported solid-phase catalyst. Raw materials of the present invention are inexpensive and easily available; the preparation process is simple; the catalyst has prominent catalytic effect and can be widely used in the magnesium desulfuration process in medium-sized and small-sized boilers of 75t or more to improve the recovery rate of the desulfuration by-product and reduce energy consumption of the oxidation system; the catalyst has a low amount of catalytically active components and causes low residue in the solution and hence no secondary pollution problem, and has a high generalization value.

Provided is a production method whereby corresponding carboxylic acid esters can be obtained from a variety of carboxylic acids at a high yield, even under conditions using a simple reaction operation and little catalyst and even if the amount of substrate used is theoretical. A production method for carboxylic acid ester, whereby a prescribed diester dicarbonate, carboxylic acid, and alcohol are reacted in the presence of at least one type of magnesium compound and at least one type of alkali metal compound.

Provided is a production method whereby corresponding carboxylic acid esters can be obtained from a variety of carboxylic acids at a high yield, even under conditions using a simple reaction operation and little catalyst and even if the amount of substrate used is theoretical. A production method for carboxylic acid ester, whereby a prescribed diester dicarbonate, carboxylic acid, and alcohol are reacted in the presence of at least one type of magnesium compound and at least one type of alkali metal compound.

The present invention relates to a catalyst system for olefin metathesis, the catalyst system comprising: a) a first system zone substantially comprising a layered double hydroxide; and b) a second system zone comprising a metathesis catalyst.