Process for making cyclohexylbenzene

A kind of technology of cyclohexylbenzene and dicyclohexylbenzene, applied in the field of preparation of cyclohexylbenzene, can solve problems such as difficult separation

Inactive Publication Date: 2011-09-07
EXXONMOBIL CHEM PAT INC
View PDF23 Cites 29 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the similar boiling points of benzene, cyclohexane, and methylcyclopentane make separation difficult by conventional distillation

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Process for making cyclohexylbenzene
  • Process for making cyclohexylbenzene
  • Process for making cyclohexylbenzene

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0021] U.S. Patent Application No. 61 / 047,821, filed April 25, 2008, the disclosure of which is incorporated by reference in its entirety, discloses a process for the preparation of cyclohexylbenzene in which benzene and hydrogen are reacted with a first catalyst in an atmosphere sufficient to produce ring-containing The first effluent stream of hexylbenzene, cyclohexane and unreacted benzene is contacted under hydroalkylation conditions. Then at least a portion of the first effluent stream containing cyclohexane and unreacted benzene is contacted with a second catalyst under dehydrogenation conditions to convert at least a portion of the cyclohexane to benzene and / or biphenyl, and A second effluent stream containing less cyclohexane than the first effluent stream is produced. At least a portion of the second effluent stream is recycled back to the first contacting (hydroalkylation) step.

[0022] In the process of the present invention, cyclohexylbenzene is produced by conta...

Embodiment 1-9

[0061] Examples 1-9. CHB production under various process conditions

[0062] 8 grams of the catalyst prepared above were charged into a stainless steel fixed bed microreactor. The reactor had a 1 / 2-inch inner diameter with a 1 / 8-inch thermowell in the center of the entire catalyst bed. The catalyst was pretreated with 100 cubic centimeters per minute (cc / min) of hydrogen at 300°C and 1 atmosphere (atm) for 2 hours (hr). After cooling to 155°C in hydrogen, benzene was fed to the reactor via a syringe pump at 60 cc / hour for 1 hr while the reactor pressure was increased to 150 pounds per square inch gauge (psig). The benzene rate was then reduced to 0.52 weight hourly space velocity (WHSV) and the hydrogen / benzene molar ratio was adjusted to 1.28. The liquid product was collected in cold product hydrazine and analyzed off-line. Catalyst performance was evaluated using various test conditions by varying four process variables. Table 1 shows these process variables and their r...

Embodiment 10 and 11

[0066] Examples 10 and 11: Cyclohexane / methylcyclopentane dehydrogenation

[0067] The reactor used in the experiments was stainless steel with dimensions 22 inches (in.) long x 3 / 8 in. outside diameter (o.d.) x 0.035 in. wall thickness. A piece of 8 3 / 4 in. long x 1 / 4 in.o.d stainless steel tubing was used at the bottom of the reactor as a spacer and to support the catalyst in the isothermal zone of the furnace. A 1 / 4 in. glass wool plug was placed on top of the spacer to keep the catalyst in place. A 1 / 8 in. thermowell was placed in the catalyst bed, long enough to accommodate a temperature sweep across the catalyst bed.

[0068] The catalyst was pressed into pellets, then crushed and sieved to 20-40 US mesh. Typically, 2.5 grams (g) of catalyst pre-screened to 20-40 mesh was diluted to a volume of 5.5 cc with quartz chips of the same size. The mixed portion of catalyst is then loaded into the reactor from the top. The catalyst bed is typically 12.5 cm. long. A 1 / 4 in. ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

A process for making cyclohexylbenzene includes (a) contacting benzene and hydrogen in the presence of a first catalyst under hydroalkylation conditions sufficient to form a first effluent stream having cyclohexylbenzene, cyclohexane, methyl cyclopentane, and unreacted benzene, (b) supplying a portion of the first effluent stream to a first separation system to divide the first effluent stream part into (i) a C6-rich stream comppsing benzene, cyclohexane, and methylcyclopentane and (II) a cyclohexylbenzene-rich stream, (c) contacting a portion of the C6-rich stream with a second catalyst that catalyzes dehydrogenation and exhibits low acidity under conditions sufficient to convert a portion of the cyclohexane to benzene and a portion of the methylcyclopentane to linear and / or branched paraffins to form a second effluent stream, and (d); recycling a portion of the second effluent stream to the contacting step (a).

Description

technical field [0001] The present disclosure relates to a process for the preparation of cyclohexylbenzene. Background technique [0002] Cyclohexylbenzene can be prepared from benzene by hydroalkylation or reductive alkylation methods. Benzene is heated with hydrogen in the presence of a catalyst such that the benzene undergoes partial hydrogenation to produce cyclohexene which then alkylates the benzene to form cyclohexylbenzene. [0003] US Patent Nos. 4,094,918 and 4,177,165 disclose the hydroalkylation of aromatic hydrocarbons over nickel and rare earth treated zeolite catalysts and palladium promoters. Similarly, US Patent Nos. 4,122,125 and 4,206,082 disclose the use of ruthenium and nickel compounds supported on rare earth treated zeolites as aromatic hydroalkylation catalysts. The zeolites used were zeolites X and Y. Additionally, US Patent No. 5,053,571 proposes the use of ruthenium and nickel supported on zeolite beta as an aromatic hydroalkylation catalyst. ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C07C2/64C07C2/66
CPCC07C2/74C07C2601/14C07C13/28C07C2/66
Inventor J·M·达卡L·C·德卡乌徐腾
Owner EXXONMOBIL CHEM PAT INC
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products