The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.

The present invention relates to a ligand compound, an organic chromium compound, a catalyst system for ethylene oligomerization, a preparation method thereof, and an ethylene oligomerization method using the same. The catalyst system for ethylene oligomerization according to the present invention is used to prepare a low-density polyethylene in one reactor by using a small amount of comonomers such as alpha-olefin or by using only ethylene without comonomers, because it maintains high catalytic activity and high alpha-olefin selectivity even though supported on a support.

A catalyst for performing carbon dioxide reforming of methane to produce syngas, that includes cobalt, nickel and magnesium oxides disposed a support.

The present invention relates to a catalyst for the removal of carbon monoxide and hydrocarbon from the exhaust gas of lean-operated internal combustion engines on a supporting body, which bears platinum and/or palladium on one or more refractory carrier materials and also contains cerium oxide and which, after reductive treatment at 250° C. and after CO adsorption, is characterized by certain peaks in Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS), and also relates to the use thereof for removing carbon monoxide and hydrocarbon from the exhaust gas of lean-operated internal combustion engines.

Cu.sub.y/MMgO.sub.x interfacial catalyst for selective alkyne hydrogenation and its preparation method are disclosed. The preparation method of the catalyst includes: the mixture of salt and alkali solution is nucleated momentarily by nucleation/crystallization isolation method, preparing the composite metal hydroxide Cu.sub.yMMg.sub.4-LDHs as precursor, which has typical hexagonal morphology of the double hydroxide; the precursor is topologically transformed by heat treatment to produce unsaturated oxide; the catalyst with Cu.sub.y-MMgO.sub.x interface structure is prepared by separating and electronically modifying Cu particles. By adjusting the ratio of Cu.sup.2+/M.sup.3+ in LDHs, the electronic and geometric structure of Cu.sub.y-MMgO.sub.x interface can be flexibly controlled, thus enhancing the reaction activity, product selectivity and stability. The catalyst can be used in the selective hydrogenation of various alkynes in the fields of petrochemical and fine chemical industry, with the outstanding catalytic activity and C═C double bond selectivity. The catalyst also has good reusability.

A heterogeneous catalyst comprising a support and a noble metal. The catalyst has an average diameter of at least 200 microns and at least 90 wt % of the noble metal is in the outer 50% of catalyst volume.

A nanomaterial catalyst comprising a partially crystalline porous magnesium silicate support and gold nanoparticles, the catalyst being useful for oxidative cracking of hydrocarbons, specifically the production of light olefins from propane. Methods of producing the nanomaterial catalyst as well as a method of oxidative cracking of a hydrocarbon to produce light olefins are provided.

A nanomaterial catalyst comprising a partially crystalline porous magnesium silicate support and gold nanoparticles, the catalyst being useful for oxidative cracking of hydrocarbons, specifically the production of light olefins from propane. Methods of producing the nanomaterial catalyst as well as a method of oxidative cracking of a hydrocarbon to produce light olefins are provided.

It is an object to provide a catalyst that can effectively purify exhaust gas, in particular, carbon monoxide (CO) in exhaust gas, emitted from a diesel engine, a production method therefor, and an exhaust gas purification method using the same. A diesel engine exhaust gas purification catalyst for purifying exhaust gas emitted from a diesel engine of the present invention comprises a precious metal and alumina and/or zeolite supported on a three-dimensional structure, and has peaks for not less than three different pore sizes in a pore size distribution measured by the mercury intrusion method, wherein one of the peaks is a peak 2 at a pore size of not less than 0.3 μm and less than 1.0 μm, and the pore volume of the peak 2 being greater than 3.1% of the total pore volume.

It is an object to provide a catalyst that can effectively purify exhaust gas, in particular, carbon monoxide (CO) in exhaust gas, emitted from a diesel engine, a production method therefor, and an exhaust gas purification method using the same. A diesel engine exhaust gas purification catalyst for purifying exhaust gas emitted from a diesel engine of the present invention comprises a precious metal and alumina and/or zeolite supported on a three-dimensional structure, and has peaks for not less than three different pore sizes in a pore size distribution measured by the mercury intrusion method, wherein one of the peaks is a peak 2 at a pore size of not less than 0.3 μm and less than 1.0 μm, and the pore volume of the peak 2 being greater than 3.1% of the total pore volume.