A process and system for converting bio ethanol to high purity isobutene is provided. The system includes a dehydration unit configured to receive a bio ethanol containing stream, convert the bio ethanol to bio ethylene, and produce a bio ethylene containing stream, a dimerization unit configured to receive the bio ethylene stream, dimerize ethylene, and produce an n-butenes containing stream, a skeletal isomerization unit configured to receive the n-butenes containing stream, convert n-butenes to produce a skeletal isomerization stream comprising an isobutene, isobutane, n-butenes, and n-butane, and a catalytic separation unit configured to receive the skeletal isomerization stream, convert olefins and/or isoolefins contained therein to produce a converted skeletal isomerization reaction product, and to fractionate the skeletal isomerization reaction product and produce bio isobutene.

A process and system for converting bio ethanol to high purity isobutene is provided. The system includes a dehydration unit configured to receive a bio ethanol containing stream, convert the bio ethanol to bio ethylene, and produce a bio ethylene containing stream, a dimerization unit configured to receive the bio ethylene stream, dimerize ethylene, and produce an n-butenes containing stream, a skeletal isomerization unit configured to receive the n-butenes containing stream, convert n-butenes to produce a skeletal isomerization stream comprising an isobutene, isobutane, n-butenes, and n-butane, and a catalytic separation unit configured to receive the skeletal isomerization stream, convert olefins and/or isoolefins contained therein to produce a converted skeletal isomerization reaction product, and to fractionate the skeletal isomerization reaction product and produce bio isobutene.

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.

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.

Provided is a method of producing a porous molded body, the method including: the step of obtaining a molded body by molding a raw material that contains from 1 part by mass to 100 parts by mass of a bicarbonate compound (A) represented by AHCO.sub.3 (wherein, A represents Na or K) and from 0 parts by mass to 99 parts by mass of a compound (B) represented by B.sub.nX (wherein, B represents Na or K; X represents CO.sub.3, SO.sub.4, SiO.sub.3, F, Cl, or Br; and n represents an integer of 1 or 2 as determined by the valence of X) (provided that a total amount of (A) and (B) is 100 parts by mass); and the step of obtaining a porous molded body by performing a heat treatment of the molded body in a temperature range of from 100° C. to 500° C. and an atmosphere that contains water vapor in an amount of from 1.0 g/m.sup.3 to 750,000 g/m.sup.3 and thereby thermally decomposing not less than 90% by mass of the bicarbonate compound (A).

An oligomerization catalyst, oligomer products, methods for making and using same. The catalyst can include a supported nickel phosphate compound. The catalyst is stable at oligomerization temperatures of 500° C. or higher and particularly useful for making oligomer products containing C4 to C26 olefins having a boiling point in the range of 170° C. to 360° C.

An oligomerization catalyst, oligomer products, methods for making and using same. The catalyst can include a supported nickel phosphate compound. The catalyst is stable at oligomerization temperatures of 500° C. or higher and particularly useful for making oligomer products containing C4 to C26 olefins having a boiling point in the range of 170° C. to 360° C.

Provided is an apparatus for preparing oligomer including: a reactor for carrying out oligomerization reaction by supplying a monomer stream and a solvent stream; and line 1 and line 2 which are separately provided in a lower side of the reactor, wherein line 1 includes a first level control valve and line 2 includes a second level control valve, and the reactor is periodically alternately operated in first operation mode and second operation mode, thereby switching a pipe through which the product is discharged, so that a plugging phenomenon of the pipe through which the product is discharged and the valve can be prevented.

Provided is an apparatus for preparing oligomer including: a reactor for carrying out oligomerization reaction by supplying a monomer stream and a solvent stream; and line 1 and line 2 which are separately provided in a lower side of the reactor, wherein line 1 includes a first level control valve and line 2 includes a second level control valve, and the reactor is periodically alternately operated in first operation mode and second operation mode, thereby switching a pipe through which the product is discharged, so that a plugging phenomenon of the pipe through which the product is discharged and the valve can be prevented.

Methods for recycling ethylene from a reaction zone effluent stream from an oligomerization reaction zone, in which the reaction zone effluent stream contains an oligomer product effluent having at least 20 mass % octene(s), include a step of separating the reaction zone effluent stream into a first stream containing ethylene and less than 5 mass % C.sub.4+ olefins, a second stream containing butene(s) and less than 10 mass % C.sub.6+ olefins, a third stream containing at least 96 mass % hexene(s), and a fourth stream containing at least 96 mass % octene(s). The ethylene-rich first stream is recycled into the oligomerization reaction zone, while the recycle of 1-butene and other butenes is reduced significantly.