Disclosed is a flow bypass device, a reactor system containing the flow bypass device; a method for operating a fixed bed of solid particles in which gas is re-routed to an interior of the fixed bed, for example, the flow bypass device is used to bypass a portion of the solid particles; and a method for loading solid particles and a flow bypass device into a vessel. The methods and systems can use a single flow bypass device or multiple flow bypass devices that are stacked on top of one another.

A system and a process for co-producing dimethyl carbonate and ethylene glycol. The system comprises an interconnected ethylene carbonate preparation unit and an ethylene carbonate alcoholysis unit. The ethylene carbonate preparation unit comprises a fixed bed reactor and a light-component stripping column connected to each other. The fixed bed reactor is filled with a supported ionic liquid catalyst. The process comprises the steps of: reacting carbon dioxide and ethylene oxide as raw materials in the fixed bed reactor to produce ethylene carbonate, purifying the ethylene carbonate and then mixing it with an alcoholysis reaction catalyst, and reacting the mixture with methanol in a reactive distillation tower, producing dimethyl carbonate and ethylene glycol. The process increases the conversion rate of ethylene oxide and avoids the need for a process of separating conventional homogeneous catalysts from ethylene carbonate, thereby reducing process energy consumption and simplifying process procedures.

An upflow reactor (1), comprising a housing (20), a catalyst bed layer (30) and a pressing device (10). The housing (20) is internally provided with a reaction chamber (210), a reaction material inlet (220) and a reaction material outlet (230) which are in communication with the reaction chamber (210) are provided on the housing (20); the catalyst bed layer (30) is provided within the reaction chamber (210), the pressing device (10) is provided within the reaction chamber (210) and located above the catalyst bed layer (30), and at least a part of the pressing device (10) is provided to be movable up and down, so that the at least a part of the pressing device (10) can be pressed against the catalyst bed layer (30).

The invention involves a scale collection device that is located within downflow reactor head for removing solids from feed streams to increase reactor operating cycle time without impact on effective reactor space for catalyst loading. More particularly, a filtering zone is located in an upper portion of a reactor vessel above a rough liquid distribution tray and a distribution tray.

An aspect of the present disclosure relates to a process for preparing a composite hydroalkylation catalyst including: (a) effecting impregnation of a hydrogenation metal on an inorganic oxide to form a metal impregnated inorganic oxide; (b) effecting calcination of the metal impregnated inorganic oxide to obtain a calcined metal impregnated inorganic oxide; (c) preparing a composite mixture comprising a molecular sieve, the calcined metal impregnated inorganic oxide and a binder; (d) preparing an extruded catalyst; and (e) effecting calcination of the extruded catalyst to obtain the composite hydroalkylation catalyst. The composite hydroalkylation catalyst prepared using this process affords dramatic improvement in conversion of mononuclear aromatic hydrocarbon and the yield of the hydroalkyled mononuclear aromatic hydrocarbon (e.g. CHB).

Methods of sulfurizing metal containing particles in the absence of hydrogen are described. One method includes contacting a bed of metal containing particles with a gaseous stream comprising hydrogen sulfide and inert gas under reaction conditions sufficient to produce sulfided metal containing particles. The gaseous stream is introduced into a vertical reactor at an inlet positioned at the bottom portion of the reactor and any unreacted hydrogen sulfide and inert gas is removed at an outlet positioned above the inlet. The sulfided metal containing particles can be removed from the reactor and stored.

A system and a process for co-producing dimethyl carbonate and ethylene glycol. The system comprises an interconnected ethylene carbonate preparation unit and an ethylene carbonate alcoholysis unit. The ethylene carbonate preparation unit comprises a fixed bed reactor and a light-component stripping column connected to each other. The fixed bed reactor is filled with a supported ionic liquid catalyst. The process comprises the steps of: reacting carbon dioxide and ethylene oxide as raw materials in the fixed bed reactor to produce ethylene carbonate, purifying the ethylene carbonate and then mixing it with an alcoholysis reaction catalyst, and reacting the mixture with methanol in a reactive distillation tower, producing dimethyl carbonate and ethylene glycol. The process increases the conversion rate of ethylene oxide and avoids the need for a process of separating conventional homogeneous catalysts from ethylene carbonate, thereby reducing process energy consumption and simplifying process procedures.

In a catalytic reaction, after a reaction product leaves a catalyst bed, an inert substance with a low temperature is sprayed, and through heat absorption and vaporization processes of the inert substance, the temperature of the reaction product drops rapidly when staying in a catalyst cushion layer at a discharge end of a fixed bed reactor, or in a space formed by the catalyst cushion layer at the discharge end of the fixed bed reactor and a reactor head, or in a space formed by a tube plate at the discharge end of the fixed bed reactor and the reactor head. The residence time of the reaction product is shortened due to the entrance of the inert substance in a gaseous state.

A catalyst composition for hydrogenating 4,4′-methylenedianiline derivatives is provided. The catalyst composition includes a carrier including aluminum oxide and magnesium oxide, a rhodium-ruthenium active layer loaded on the surface of the carrier, and a solvent including an organic amine. The weight percentage of magnesium oxide in the carrier is between 12% and 30%. A method for preparing 4,4′-methylene bis(cyclohexylamine) derivatives using the catalyst composition is also provided.

A process for continuous dissolution of a solid in a reaction medium includes: (a) providing a liquid by withdrawal of a portion of the reaction medium from a first reaction vessel; (b) contacting the liquid provided in (a) with the solid in a second reaction vessel to form a solution of the solid; and (c) recycling the solution formed in step b) into the first reaction vessel. The solid in the second reaction vessel is present in the form of a fixed bed which is traversed by the liquid.