Described is a catalyst obtained by supporting magnesium and cerium on activated alumina, firing same to immobilize the metals, and then impregnating same with palladium and performing reduction thereon, and is applied, when hydrogen peroxide is prepared by means of an anthraquinone process, to operation solution regeneration or hydrogenation, and thus an efficient regeneration conversion rate or synthesis yield is achieved.

The present invention relates to a catalyst for selective hydrodesulphurization of cracked naphtha streams in the form of an extrudate, which comprises a support based on an inorganic oxide and an outer layer bound to the support, wherein the outer layer comprises desulphurization metals dispersed therein forming a crown, the desulphurization metals being cobalt and molybdenum. The present invention also relates to the preparation of said catalyst by the incipient wetness impregnation method and to the process for selective hydrodesulphurization of cracked naphtha employing same.

The invention relates to a core-shell structured catalyst comprising a core covered with a shell, the core is made of hematite, tourmaline, germanium, maifanite or kaolin. The invention also provides a method for preparing the catalyst including mixing raw materials of the core with water to form seed-balls with a particle size of 2-4 mm; mixing the seed-balls with raw materials of the shell and water, such that the seed-balls are covered with the raw materials of the shell to form pellets with a particle size of 3-5 mm; processing the pellets at 60-90 C. and then calcining to active the pellets at 450-550 C. to obtain a core-shell structured catalyst. The invention further discloses use of the core-shell structured catalyst in the ozone oxidation reaction. In the invention, a core-shell structured catalyst with good morphology and catalytic performance is prepared, and the production cost of the catalyst is reduced.

A method for preparing methyl methacrylate from methacrolein and methanol; said method comprising contacting in a reactor a mixture comprising methacrolein, methanol and oxygen with a heterogeneous catalyst comprising a support and a noble metal, wherein pH at the reactor outlet is from 3 to 6.7.

Disclosed herein is a photocatalytic filter, which includes a plurality of cross-linked polymethyl methacrylate (PMMA)/ionic liquid (IL)/TiO.sub.2 nanocomposite pellets, and a photocatalytic vessel. The plurality of cross-linked PMMA/IL/TiO.sub.2 nanocomposite pellets is placed within the photocatalytic vessel. Each cross-linked PMMA/IL/TiO.sub.2 nanocomposite pellet includes a PMMA polymeric matrix, and a plurality of IL/TiO.sub.2 core-shell microspheres dispersed within the PMMA polymeric matrix. Moreover, each IL/TiO.sub.2 core-shell microsphere includes a core of IL and a shell of TiO.sub.2 nanoparticles.

A method for preparing methyl methacrylate from methacrolein and methanol. The method comprises contacting a mixture comprising methacrolein, methanol and oxygen with a heterogeneous catalyst comprising a support and a noble metal, wherein said 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 method for preparing methyl methacrylate from methacrolein and methanol. The method comprises contacting a mixture comprising methacrolein, methanol and oxygen with a heterogeneous catalyst comprising a support and a noble metal, wherein said catalyst has an average diameter of at least 200 microns and at least 90 wt % of the noble metal is in the outer 70% of catalyst volume, and wherein oxygen concentration at a reactor outlet is from 0.5 to 7.5 mol %.

A method for preparing methyl methacrylate from methacrolein and methanol. The method comprises contacting in a reactor a mixture comprising methacrolein, methanol and oxygen with a heterogeneous catalyst comprising a support and a noble metal, wherein said catalyst has an average diameter of at least 200 microns, wherein oxygen concentration at a reactor outlet is from 0.5 to 7.5 mol % and wherein the reactor comprises a partition with the catalyst bed on a first side of the partition and with flow through the catalyst bed in a first direction and flow on a second side of the partition in an opposite direction.

A method for scaled-up synthesis of PtNi nanoparticles. Synthesizing a Pt nanoparticle catalyst comprises the steps of: synthesizing PtNi nanoparticles, isolating PtNi/substrate nanoparticles, acid leaching the PtNi/substrate, and annealing the leached PtNi/substrate nanoparticles, and forming a Pt-skin on the PtNi/substrate nanoparticles.

The present disclosure is related to a method for preparing a gaseous- or liquid-nitridation treated core-shell catalyst and, more specifically, to a method for preparing a gaseous- or liquid-nitridation treated core-shell catalyst comprising steps of: nitridation-treating a transition metal precursor core and noble metal precursor shell particles in the presence of a gaseous nitrogen source; or forming a transition metal precursor core and noble metal precursor shell particles, by means of a liquid nitrogen source, and at the same time allowing the nitrogen source to bond with the transition metal precursor and thus allowing nitridation treatment. Therefore, the present disclosure allows a high nitrogen content in the core and thus enables a prepared catalyst to have excellent durability, a small average particle size and high degree of dispersion and uniformity, and thus to be suitable for the fuel cell field.