A bi-modal radial flow reactor comprising a cylindrical outer housing surrounding at least five cylindrical, concentric zones, including at least three annulus vapor zones and at least two catalyst zones. The at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone. The at least three annulus vapor zones comprise an outer annulus vapor zone, a middle annulus vapor zone, and a central annulus vapor zone, wherein the central annulus vapor zone extends along a centerline of the bi-modal radial flow reactor. The outer catalyst zone is intercalated with the outer annulus vapor zone and the middle annulus vapor zone, and the inner catalyst zone is intercalated with the middle annulus vapor zone and the central annulus vapor zone. A removable head cover can be fixably coupled to a top of the cylindrical outer housing to seal a top of the bi-modal radial flow reactor.

Provided is a propylene oxide production apparatus including a switching mechanism that is capable of switching a state of each reactor between an operating state where reaction raw materials are supplied and an epoxidation reaction is performed and a non-operating state where the supply of the reaction raw materials is shut off. The propylene oxide production apparatus is capable of changing a reactor in the non-operating state one by one, and performs switching in such a way that only reactors in the operating state are connected fluidically in series or in parallel, thereby enabling supplying the reaction raw materials to the reactors in the operating state. A sampling mechanism is also provided that samples part of the reaction mixture from each discharge line that is connected to each reactor.

The selective dimerization of isoolefins, such as isobutene or isopentane, or mixtures thereof, may be conducted in a system including a series of fixed bed reactors and a catalytic distillation reactor. The system may provide for conveyance of the fixed bed reactor effluents, without componential separation, to a downstream reactor. It has been found that a high selectivity to the dimer may be achieved even though intermediate separation of the desired product from unreacted components between reactors is not performed. Further, embodiments provide for use of a divided wall column for recovery of a high purity dimer product, reducing unit piece count and plot size.

A method for preparing polybutene includes the steps of: supplying a C4 mixture to an isomerization reactor in which (i) 1-butene is isomerized into 2-butene by a hydrogen isomerization reaction using an isomerization catalyst in an isomerization zone of the isomerization reactor and (ii) iso-butene and 2-butene are separated by fractional distillation in a fractional distillation zone; supplying a C4 mixture containing 2-butene which is separated in the isomerization reactor to a skeletal isomerization reactor, in which a part of normal-butene is skeletal isomerized into iso-butene by a skeletal isomerization reaction using a skeletal isomerization catalyst, and the obtained skeletal isomerization mixture is supplied and recycled to the isomerization reactor; and supplying (i) a raw material containing the iso-butene of high concentration and which is separated from the isomerization reactor and (ii) a polymerization catalyst to a polybutene polymerization reactor and thereby producing polybutene by a polymerization reaction.

The selective dimerization of isoolefins, such as isobutene or isopentane, or mixtures thereof, may be conducted in a system including a series of fixed bed reactors and a catalytic distillation reactor. The system may provide for conveyance of the fixed bed reactor effluents, without componential separation, to a downstream reactor. It has been found that a high selectivity to the dimer may be achieved even though intermediate separation of the desired product from unreacted components between reactors is not performed. Further, embodiments provide for use of a divided wall column for recovery of a high purity dimer product, reducing unit piece count and plot size.

A bi-modal radial flow reactor comprising a cylindrical outer housing surrounding at least five cylindrical, concentric zones, including at least three annulus vapor zones and at least two catalyst zones. The at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone. The at least three annulus vapor zones comprise an outer annulus vapor zone, a middle annulus vapor zone, and a central annulus vapor zone, wherein the central annulus vapor zone extends along a centerline of the bi-modal radial flow reactor. The outer catalyst zone is intercalated with the outer annulus vapor zone and the middle annulus vapor zone, and the inner catalyst zone is intercalated with the middle annulus vapor zone and the central annulus vapor zone. A removable head cover can be fixably coupled to a top of the cylindrical outer housing to seal a top of the bi-modal radial flow reactor.

The selective dimerization of isoolefins, such as isobutene or isopentane, or mixtures thereof, may be conducted in a system including a series of fixed bed reactors and a catalytic distillation reactor. The system may provide for conveyance of the fixed bed reactor effluents, without componential separation, to a downstream reactor. It has been found that a high selectivity to the dimer may be achieved even though intermediate separation of the desired product from unreacted components between reactors is not performed. Further, embodiments provide for use of a divided wall column for recovery of a high purity dimer product, reducing unit piece count and plot size.

Methods for utilizing carbon dioxide to produce multi-carbon products are disclosed. The systems and methods of the present disclosure involve: reducing CO.sub.2 to produce a first product mixture comprising an alcohol product mixture comprising one or more alcohols and a paraffin product mixture comprising one or more paraffins; dehydrating the alcohol product mixture to form an olefin product mixture comprising one or more olefins; oligomerizing the olefin product mixture to form a higher olefin product mixture comprising unsaturated paraffins and optionally aromatics; and reducing the higher olefin product mixture to form a higher hydrocarbon product mixture comprising unsaturated paraffins and optionally aromatics. Catalyst materials and reaction conditions for individual steps are disclosed to optimize yield for ethanol or jet fuel range hydrocarbons.

The invention provides a reaction system for the production of ethylene carbonate and/or ethylene glycol. The system having a guard bed system upstream of a catalytic EO reactor. The guard bed system having a feed line supplying a gaseous feed to be treated and an effluent line configured to remove the treated gaseous feed. The guard bed system has two or more guard bed vessels arranged in series in sequential order, each having an inlet, a bed of guard bed material and an outlet. The inlet of each guard bed vessel is attached by means of valves to both the feed line and the outlet of the guard bed vessel preceding it in sequential order. The outlet of each guard bed vessel is attached by means of valves to both the effluent line and to the inlet of the guard bed vessel following it in sequential order.

A bi-modal radial flow reactor comprising a cylindrical outer housing surrounding at least five cylindrical, concentric zones, including at least three annulus vapor zones and at least two catalyst zones. The at least two catalyst zones comprise an outer catalyst zone and an inner catalyst zone. The at least three annulus vapor zones comprise an outer annulus vapor zone, a middle annulus vapor zone, and a central annulus vapor zone, wherein the central annulus vapor zone extends along a centerline of the bi-modal radial flow reactor. The outer catalyst zone is intercalated with the outer annulus vapor zone and the middle annulus vapor zone, and the inner catalyst zone is intercalated with the middle annulus vapor zone and the central annulus vapor zone. A removable head cover can be fixably coupled to a top of the cylindrical outer housing to seal a top of the bi-modal radial flow reactor.