A method and an apparatus for preparing an alpha-olefin. The method includes supplying a feed stream including a gaseous ethylene monomer to a monomer dissolution device to dissolve the feed stream in a solvent and form a liquid ethylene monomer, and supplying a feed stream including the liquid ethylene monomer as a discharge stream to a reactor, thereby removing heat of dissolution of the gaseous ethylene monomer outside of the reactor, and decreasing an amount of a refrigerant used in an alpha-olefin production process to improve economic feasibility.

The present invention relates to the field of gas/liquid reactors permitting the oligomerization of olefins to give linear olefins by homogeneous catalysis, comprising a reaction chamber and vertical internal means of compartmentalization.

Processes for producing olefins include integration of steam cracking with a dual catalyst metathesis process. The processes include steam cracking a hydrocarbon feed to form a cracking reaction effluent containing butenes, separating the cracking reaction effluent to produce a cracking C4 effluent including normal butenes, isobutene, and 1,3-butadiene, subjecting the cracking C4 effluent to selective hydrogenation to convert 1,3-butadiene in the cracking C4 effluent to normal butenes, removing isobutene from a hydrogenation effluent to produce a metathesis feed containing normal butenes, and contacting the metathesis feed with a metathesis catalyst and a cracking catalyst directly downstream of the metathesis catalyst to produce a metathesis reaction effluent. Contacting with the metathesis catalyst causes metathesis of normal butenes to produce ethylene, propene, and C5+ olefins, and contacting with the cracking catalyst causes C5+ olefins produced through metathesis to undergo cracking reactions to produce additional propene, ethylene, or both.

A chemical vessel utilizing induction heating elements and useful for preparing polyamides, such as nylon. The vessel can utilize an array of induction heating elements located inside a process chamber. Also described are a vessel, a heat exchanger, a process, and an apparatus useful for polyamide preparation.

A system and a method for producing silicon from a SiO.sub.2-containing material that includes solid SiO.sub.2. The method uses a reaction vessel including a first section and a second section in fluid communication with said first section. The method includes: heating the SiO.sub.2-containing material that includes the solid SiO.sub.2 to a SiO.sub.2-containing material that includes liquid SiO.sub.2, at a sufficient temperature to convert the solid SiO.sub.2 into the liquid SiO.sub.2; converting, in the first section, the liquid SiO.sub.2 into gaseous SiO.sub.2 that flows to the second section by reducing the pressure in the reaction vessel to a subatmospheric pressure; and reducing, in the second section, the gaseous SiO.sub.2 into liquid silicon using a reducing gas. The reducing of the pressure is performed over a continuous range of interim pressure(s) sufficient to evaporate contaminants from the SiO.sub.2-containing material, and removing by vacuum, the one or more evaporated gaseous contaminants.

The present disclosure provides a device for continuously preparing 2,6-dihydroxybenzaldehyde and use thereof. The device includes a first continuous reaction unit for hydroxy protection reaction, a second continuous reaction unit for lithiation and hydroformylation, and a third continuous reaction unit for deprotection reaction that are connected in series. The third continuous reaction unit includes: a first columnar continuous reactor, connected to the second continuous reaction unit and used for deprotection of the lithiated hydroformylated product while performing liquid separation to obtain an organic phase containing 2,6-dihydroxybenzaldehyde and an aqueous phase. When the device is applied in the preparation of 2,6-dihydroxybenzaldehyde, reaction time is shortened and the intermediate purification treatment is no longer required. Therefore, compared with batch process, the present disclosure can greatly save equipment cost and post-processing cost, and greatly improve the production efficiency, more beneficial to the industrial scale-up production of 2,6-dihydroxybenzaldehyde.

Provided herein are systems, and methods of using such systems, for producing acrylic acid from ethylene oxide and carbon monoxide on an industrial scale. The composition includes: polypropiolactone having a concentration of greater than at least 90 wt %; a residual cobalt or ions thereof from a carbonylation catalyst in an amount of 10 ppm or less; acetic acid in an amount of 10 ppm or less; and tetrahydrofuran in amount of 10 ppm or less.

Multi-reactor systems for the production of low-density polyethylene (LDPE) polymers and copolymers, wherein a first reactor product stream has a total mass flow of from about 10% to about 80% of the total mass flow of the second reactor product stream, methods of using the same, and processes of monitoring the same.

An agitator or mixer installed in a solid-liquid-gas/slurry reactor in which gas removal from the slurry and foam destruction is promoted. The reaction mixer includes a vessel and an agitator assembly. The vessel is for containing the solid-liquid-gas mixture and defines two mixing zones within a given volume; a first mixing zone and a second mixing zone located above the first mixing zone. The agitator assembly is positionable within the vessel and comprises a rotatable shaft and a first and second impeller coupled to the shaft. The first axial impeller is locatable within the first mixing zone and is configured to pump the liquid in a downward direction along a vertical axis of rotation. The second impeller is locatable within the second fluxing zone and is configured to pump the liquid in an upward direction along the vertical axis of rotation.

The present invention relates to a continuous olefin polymerization process comprising polymerization of at least one olefin monomer in at least two serial vapor phase polymerization reactors containing an agitated bed of forming polymer particles, comprising a polymer particles transfer step wherein forming polymer particles are transferred from an upstream reactor to a downstream reactor comprising in a repeating sequence the steps of discharging at least one charge of polymer powder and reactive gases from the upstream reactor into a gas-solid separator; collecting the polymer powder separated in the gas-solid separator in a pressure transfer chamber; increasing the pressure in the pressure transfer chamber with a pressurizing gas to a pressure that is higher than the operating pressure of the downstream reactor; and discharging the polymer powder from the pressure transfer chamber into the downstream reactor, wherein said process reduces the carry-over of reactive gases from the upstream reactor to the downstream reactor. The present invention further relates to a system suitable for the present continuous vapor phase olefin polymerization process. The present invention further relates to the use of the present process and system for producing heterophasic polypropylene copolymers.