This disclosure relates to processes for converting saturated polyethylene to at least an alkene product. The processes comprise contacting the saturated polyethylene with three or more catalyst components in a reactor, the reactor comprising an alkene reactant. The three or more catalyst components comprise a metathesis catalyst component, an isomerization catalyst component, and a dehydrogenation catalyst component. Contacting causes at least a portion of the saturated polyethylene to undergo dehydrogenation reactions to form unsaturated polyethylene and at least a portion of the unsaturated polyethylene, or products derived therefrom, to undergo metathesis reactions and isomerization reactions to produce an effluent comprising at least the alkene product.

Provided is a refining apparatus of a waste plastic pyrolysis oil including a reactor where a waste plastic pyrolysis oil is introduced and hydrotreated, wherein the reactor includes Area 1 including a hydrotreating catalyst having a Mo content of 1 to 15 wt % with respect to the total weight; and Area 2 including a hydrotreating catalyst having a Mo content of 5 to 40 wt % and a Ni or Co content of 4 to 50 wt % with respect to the total weight, and the waste plastic pyrolysis oil is refined by passing through Area 1 and Area 2 sequentially.

Methods for making a supported chromium catalyst are disclosed, and can comprise contacting a silica-coated alumina containing at least 30 wt. % silica with a chromium-containing compound in a liquid, drying, and calcining in an oxidizing atmosphere at a peak temperature of at least 650 C. to form the supported chromium catalyst. The supported chromium catalyst can contain from 0.01 to 20 wt. % chromium, and typically can have a pore volume from 0.5 to 2 mL/g and a BET surface area from 275 to 550 m.sup.2/g. The supported chromium catalyst subsequently can be used to polymerize olefins to produce, for example, ethylene-based homopolymers and copolymers having high molecular weights and broad molecular weight distributions.

The present invention relates to a stoichiometric-combustion spark-ignition engine comprising a specific exhaust gas system for reducing harmful exhaust gases resulting from the combustion process. The exhaust gas system consists in the through-flow direction of a three-way catalytic converter close to the engine, an oxidation catalyst and a gasoline particulate filter.

The invention comprises a method of operating a water gas shift reactor in a transient state such as during reactor start-up, the method comprising: providing a water gas shift catalyst comprising an alkali metal or alkali metal compound; heating the water gas shift catalyst up to the reaction temperature of the water gas shift reaction under steam condensing conditions, by applying steam as a heat transfer medium for the water gas shift catalyst, and where the water gas shift catalyst has a total pore volume larger than the volume of liquid water that forms during the heating.

This disclosure generally relates to an oxide composition basically composed of cerium and zirconium that has exceptional and stable porosity, surface area and lattice oxygen mobility. The oxide composition can contain one or more other rare earth oxides other than cerium oxide. For example, some compositions can contain one or more of lanthanum oxide, yttrium oxide and neodymium oxide. The oxide composition can be useful as a catalyst, catalyst support, sensor applications and combinations thereof.

A method comprising a) contacting a solvent, a carboxylic acid, and a peroxide-containing compound to form an acidic mixture wherein a weight ratio of solvent to carboxylic acid in the acidic mixture is from about 1:1 to about 100:1; b) contacting a titanium-containing compound and the acidic mixture to form a solubilized titanium mixture wherein an equivalent molar ratio of titanium-containing compound to carboxylic acid in the solubilized titanium mixture is from about 1:1 to about 1:4 and an equivalent molar ratio of titanium-containing compound to peroxide-containing compound in the solubilized titanium mixture is from about 1:1 to about 1:20; and c) contacting a chromium-silica support comprising from about 0.1 wt. % to about 20 wt. % water and the solubilized titanium mixture to form an addition product and drying the addition product by heating to a temperature in a range of from about 50 C. to about 150 C. and maintaining the temperature in the range of from about 50 C. to about 150 C. for a time period of from about 30 minutes to about 6 hours to form a pre-catalyst.

Provided is, for example, an exhaust gas-purifying three-way catalyst which is suppressed in particle growth due to sintering of a catalytically active component on a carrier in exposure to a high temperature and thus is enhanced in purification performance, and a method for producing the same, as well as an integral structure type exhaust gas-purifying catalyst using the same.

The exhaust gas-purifying three-way catalyst of the present invention includes a composite particle which contains a base material particle having a pore size of 100 to 650 nm as measured by a mercury intrusion method and a catalytically active particle of a platinum group element supported on the base material particle, in which a content proportion of the catalytically active particle is 0.001 to 30% by mass in total in terms of metal of the platinum group element, based on a total amount of the composite particle.

Porous, extruded titania-based materials further comprising one or more quaternary ammonium compounds and/or prepared using one or more quaternary ammonium compounds, Fischer-Tropsch catalysts comprising them, uses of the foregoing, processes for making and using the same and products obtained from such processes.

Methods for synthesizing a water-soluble titanium-silicon complex are disclosed herein. The titanium-silicon complex can be utilized to produce titanated solid oxide supports and titanated chromium supported catalysts. The titanated chromium supported catalysts subsequently can be used to polymerize olefins to produce, for example, ethylene based homopolymer and copolymers.