An efficient photocatalyst nanocomposite comprising reduced graphene oxide, noble metal, and a metal oxide prepared by a one-step method that utilizes date seed extract as a reducing and nanoparticle determining size agent. The photocatalyst of the invention is a more effective sunlight photocatalyst than that prepared by traditional method in the photo decomposition of organic compounds in contaminated water.

The present invention concerns a multifunctional catalyst for the conversion of CO.sub.2 into useful products, such as CO via the reverse water gas shift reaction. The catalyst according to the invention efficiently combined a water sorption functionality with at least one catalytic functionality into a single particle, by having a solid water sorbent impregnated with at least one metal capable of converting CO.sub.2 from a gaseous mixture comprising H.sub.2 and CO.sub.2. The catalyst according to the invention allows for higher selectivity in the conversion of CO.sub.2, at more lenient conditions in terms of temperature and pressure, and improved stability of the catalyst itself. The invention also concerns a process for converting CO.sub.2, utilizing the catalyst and the use of the catalyst in the conversion of CO.sub.2.

The present invention relates to a mixed oxide of aluminium, of zirconium, of cerium, of lanthanum and optionally of at least one rare-earth metal other than cerium and lanthanum that makes it possible to repair a catalyst that retains, after severe ageing, a good thermal stability and a good catalytic activity. The invention also relates to the process for preparing this mixed oxide and also to a process for treating exhaust gases from internal combustion engines using a catalyst prepared from this mixed oxide.

Disclosed are a spherelike supermacroporous mesoporous material, a polyolefin catalyst, and a preparation method therefor and an olefin polymerization process. The spherelike supermacroporous mesoporous material has a twodimensional hexagonal ordered pore channel structures. The mesoporous material has an average pore size of 10 nm to 15 nm, a specific surface area of 300 m.sup.2/g to 400 m.sup.2/g, and an average particle size of 1 .Math.m to 3 .Math.m, based on the total mass of the mesoporous material. The mass content of water in the mesoporous material is < 1 ppm. The mass content of oxygen in the mesoporous material is < 1 ppm. When a polyolefin catalyst prepared with the mesoporous material as a carrier is used for an olefin polymerization reaction, the a polyolefin product with a narrow molecular weight distribution and a good melt index can be obtained.

A silica-alumina based composite material for making hydroprocessing catalysts, is disclosed. The silica-alumina composite material generally comprises at least two silica-aluminas, the first being a modified first silica-alumina, and the second being a second silica-alumina that is unmodified or modified. The first silica-alumina is modified to comprise silica and alumina domains and a silica-alumina interphase. The second silica-alumina may also be modified at the same time or separately to comprise silica and alumina domains and a silica-alumina interphase. The first silica-alumina and the second silica-alumina differ in one or more physical and/or chemical characteristics, e.g., the ratio of silica to alumina, surface area, pore size, pore volume, silica domain size, or alumina domain size. The invention can be used for making catalyst base materials and catalysts useful for upgrading hydrocarbon feedstocks to produce fuels, lubricants, chemicals and other hydrocarbonaceous compositions.

A method of fabricating a catalyst material comprises forming or receiving a precursor solution of an iridium precursor compound, adding a 3d orbital transition metal to the precursor solution, adding a surfactant compound to the precursor solution to provide a precursor and surfactant mixture, reacting the iridium precursor compound with a nitrate salt of an alkaline metal cation to provide a reaction product comprising an iridium nitrate, and calcining the iridium nitrate at a specified calcination temperature to convert the iridium nitrate to form catalyst particles comprising an iridium oxide.

Catalysts containing a support and a metal oxide, and reactors and methods of using the catalysts in a carbonylation reaction, such as alcohol carbonylation and ester carbonylation, are described herein. The support is typically chemically inert and has a high surface area. The metal oxide typically contains a transition metal or a mixture of metals, such as rhenium, aluminum, tungsten, molybdenum, or a combination thereof. Typically, the metal oxide is mainly atomically dispersed on the surface of the support, as indicated by STEM. For example, at least 10% of the metal oxide is atomically dispersed on the surface of the support. The method includes (i) exposing a mixture of one or more alcohols or one or more esters and carbon monoxide to the catalyst. Typically, the one or more alcohols or one or more esters and carbon monoxide are in a gas phase.

A tableted catalyst support, characterized by an alpha-alumina content of at least 85 wt.-%, a pore volume of at least 0.40 mL/g, as determined by mercury porosimetry, and a BET surface area of 0.5 to 5.0 m.sup.2/g. The tableted catalyst support is an alpha-alumina catalyst support obtained with high geometrical precision and displaying a high overall pore volume, thus allowing for impregnation with a high amount of silver, while exhibiting a surface area sufficiently large so as to provide optimal dispersion of catalytically active species, in particular metal species. The invention further provides a process for producing a tableted alpha-alumina catalyst support, which comprises i) forming a free-flowing feed mixture comprising, based on inorganic solids content, at least 50 wt.-% of a transition alumina; ii) tableting the free-flowing feed mixture to obtain a compacted body; and iii) heat treating the compacted body at a temperature of at least 1100° C., preferably at least 1300° C., more preferably at least 1400° C., in particular at least 1450° C., to obtain the tableted alpha-alumina catalyst support. The invention moreover relates to a compacted body obtained by tableting a free-flowing feed mixture which comprises, based on inorganic solids content, at least 50 wt.-% of a transition alumina having a loose bulk density of at most 600 g/L, a pore volume of at least 0.6 mL/g, as determined, and a median pore diameter of at least 15 nm. The invention moreover relates to a shaped catalyst body for producing ethylene oxide by gas-phase oxidation of ethylene, comprising at least 15 wt.-% of silver, relative to the total weight of the catalyst, deposited on the tableted alpha-alumina catalyst support. The invention moreover relates to a process for producing ethylene oxide by gas-phase oxidation of ethylene, comprising reacting ethylene and oxygen in the presence of the shaped catalyst body.

The present invention relates to a catalyst composition comprising a gold nanoparticle superlattice embedded in hierarchical porous silica and a method for manufacturing the same. The catalyst composition comprising a gold nanoparticle superlattice embedded in hierarchical porous silica according to the present invention comprises micropores and mesopores in the superlattice, so that these pores are channelized to allow the rapid access of reactants to surfaces of gold nanoparticles, and the catalyst composition is very structurally stable and has excellent catalytic activity, and thus has an effect of exhibiting a CO conversion rate of 100% at room temperature.

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.