GB2068938A - Method for the simultaneous preparation of cyclopentene and camphor - Google Patents
Method for the simultaneous preparation of cyclopentene and camphor Download PDFInfo
- Publication number
- GB2068938A GB2068938A GB8004447A GB8004447A GB2068938A GB 2068938 A GB2068938 A GB 2068938A GB 8004447 A GB8004447 A GB 8004447A GB 8004447 A GB8004447 A GB 8004447A GB 2068938 A GB2068938 A GB 2068938A
- Authority
- GB
- United Kingdom
- Prior art keywords
- borneol
- cyclopentadiene
- dehydrogenation
- cyclopentene
- camphor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C5/00—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms
- C07C5/02—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by hydrogenation
- C07C5/03—Preparation of hydrocarbons from hydrocarbons containing the same number of carbon atoms by hydrogenation of non-aromatic carbon-to-carbon double bonds
- C07C5/05—Partial hydrogenation
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J12/00—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor
- B01J12/007—Chemical processes in general for reacting gaseous media with gaseous media; Apparatus specially adapted therefor in the presence of catalytically active bodies, e.g. porous plates
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/72—Copper
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
- B01J23/89—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with noble metals
- B01J23/892—Nickel and noble metals
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C45/00—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds
- C07C45/002—Preparation of compounds having >C = O groups bound only to carbon or hydrogen atoms; Preparation of chelates of such compounds by dehydrogenation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C2601/00—Systems containing only non-condensed rings
- C07C2601/06—Systems containing only non-condensed rings with a five-membered ring
- C07C2601/10—Systems containing only non-condensed rings with a five-membered ring the ring being unsaturated
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Separation Using Semi-Permeable Membranes (AREA)
Abstract
A method for the simultaneous preparation of cyclopentene and camphor, comprises simultaneously dehydrogenating a borneol and hydrogenating cyclopentadiene at a temperature of from 180 to 270 DEG C in a reactor divided into two compartments by a hydrogen- permeable membrane made of an alloy consisting of 90 to 95% by weight of palladium and 10 to 5% by weight of nickel, rhodium or ruthenium, the dehydrogenation of borneol being effected in one compartment and the hydrogenation of cyclopentadiene being effected in the other by means of the hydrogen formed in the dehydrogenation and diffusing through the membrane.
Description
SPECIFICATION
Method for the simultaneous preparation of cyclopentene and camphor
The present invention is concerned with a method for the simultaneous preparation of cyclopentene and camphor, these products being useful, respectively, as a monomer for the production of synthetic rubbers and plastics, and in the manufacture of pharmaceuticals.
The preparation of cyclopentene by hydrogenation of cyclopentadiene in the presence of catalysts comprising skeletal metals or metals supported on carriers is known. Thus, for example,
USSR Inventor's Certificate 418019 describes the use, as catalyst for this process, of palladium supported on alumina and treated with an alkylaromatic compound and USSR Inventor's
Certificate 535099 describes the use, for the same purpose, of nickel supported on alumina with additions of titanium, vanadium and copper.
In order to obtain a high selectivity relative to cyclopentene and a maximum conversion of cyclopentadiene, the active metal in the catalysts used in these prior art methods is treated with ammonia, pyridine, thiophen or other compounds, but these treating compounds are removed from the catalyst during the process which causes contamination of the reaction product and gradual reduction in the process selectivity.
In another prior art process for the preparation of cyclopentene, U.S. Patent 3,949,011, a high selectivity with respect to cyclopentene is achieved with a total conversion of cyclopentadiene, by hydrogenation of cyclopentadiene in the presence of a catalyst which is a membrane selectively permeable to hydrogen. A preferred embodiment of this method comprises hydrogenation with hydrogen diffusing through a membrane catalyst comprising an alloy of palladium (89 to 99% by weight) and ruthenium (1 to 11% by weight), or palladium (95 to 99% by weight) and rhodium (1 to 5% by weight). This embodiment of the method enables cyclopentadiene to be selectively hydrogenated to cyclopentene, while ensuring a fine control of the amount of hydrogen diffusing through the catalyst and required for the necessary partial hydrogenation of the starting material.
A disadvantage of this latter method is, however, the necessity of using pure hydrogen and the difficulty of removing the heat evolved in the exothermic hydrogenation reaction.
It is also known to produce camphor by catalytic dehydrogenation of a borneol (i.e.
borneol or iso-borneol). Suitable catalysts for this dehydrogenation reaction are, for example, nickel, cobalt or copper reduced by hydrogen from a freshly precipitated oxide, mixtures of at least one of nickel, cobalt and copper with their oxides and/or iron oxides, or skeletal nickel and copper catalysts, or copper and nickel carbonates (cf. G.A.
Rudakov "Chemistry and Technology of
Camphor", "Lesnaja Promyshlennost" Publishing
House, Moscow, 1976, p. 106). These prior art methods have the disadvantage of a rapid drop of catalyst activity and decrease in mechanical strength of the catalyst during the process which causes contamination of the product with dustlike particles of the catalyst. Furthermore, the hydrogen evolved in the dehydrogenation is not utilized at all.
We have now developed a method for the simultaneous preparation of cyclopentene and camphor which gives camphor of better purity and uses the hydrogen evolved in the dehydrogenation of the borneol as the hydrogen required for the hydrogenation reaction.
According to the present invention, there is provided a method for the simultaneous preparation of cyclopentene and camphor, which comprises simultaneously dehydrogenating a borneol and hydrogenating cyclopentadiene at a temperature of from 180 to 2700C in a reactor divided into two compartments by a hydrogenpermeable membrane made of an alloy consisting of 90 to 95% by weight of palladium and 10 to 5% by weight of nickel, rhodium or ruthenium, the dehydrogenation of borneol being effected in one compartment and the hydrogenation of cyclopentadiene being effected in the other by means of the hydrogen formed in the dehydrogenation and diffusing through the membrane.
The dehydrogenation of borneol is preferably carried out in the presence of copper or copper oxide.
The method according to the invention is technologically simple, makes use of a simple process equipment and simultaneously produces two valuable products, i.e. cyclopentene and camphor.
In the method of the invention the hydrogen evolved from the dehydrogenation of borneol is continuously removed by diffusion through the membrane and the thermodynamic equilibrium of the dehydrogenation reaction is thus shifted towards the formation of camphor.
It is an advantage of the method according to the present invention in comparison with the prior art methods mentioned above, that the catalyst is solid and has a high mechanical strength, thus eliminating the problem of separating the desired products from catalyst particles. Furthermore, the hydrogen which diffuses through the membrane comes to the surface of the latter in a highly active atomic form which makes the cyclopentadiene hydrogenation reaction much more efficient.
The coupling of the borneol dehydrogenation reaction and the cyclopentadiene hydrogenation reaction by a membrane catalyst which is a good thermal conductor (because it is formed of metal) enables the heat evolved in the exothermic hydrogenation reaction to be transferred to the endothermic dehydrogenation reaction. This reduces the power consumption required and facilities maintaining a constant temperature over the entire surface of the catalyst which is an important factor in the commercial implementation of the two reactions.
The method according to the invention also enables the cost of providing hydrogen for the hydrogenation reaction and of purifying externally provided hydrogen to be eliminated since the hydrogen required for the hydrogenation is obtained from the borneol dehydrogenation reaction and is in an extremely pure form after diffusion through the membrane; the impurity content of this hydrogen is less than 1.10-6% by volume.
As indicated, the method according to the invention is carried out in a reactor divided into two non-communicating (apart from the diffusion of hydrogen) compartments by means of a membrane made of an alloy of palladium and nickel, rhodium or ruthenium which is selectively permeable to hydrogen. A borneol (i.e. borneol or isoborneol) vapour is introduced into one of the reactor compartments (dehydrogenation chamber) and cyclopentadiene vapour is simultaneously introduced into the other compartment (hydrogenation chamber). The starting material vapours, i.e. borneol and cyclopentadiene, may be supplied to the respective chambers of the reactor either in their pure form or in a current of an inert gaseous diluent, such as argon or helium. Borneol is dehydrogenated at the surface of the membrane catalyst with the formation of camphor.The hydrogen evolved on dehydrogenation diffuses through the membrane catalyst and, having reached its opposite surface, hydrogenates cyclopentadiene to cyclopentene. The membrane dividing the reactor into two non-communicating compartments may be in the form of a thin foil or a thin-walled tube made of the specified alloys.
As already indicated, the hydrogen-permeable membrane is made of an alloy consisting of 90 to 95% by weight of palladium and 10 to 5% by weight of nickel, rhodium or ruthenium. A lower content of nickel, rhodium or ruthenium than 5% by weight results in the membrane having poorer mechanical properties which are substantially those of pure palladium which, while being a good hydrogenation and dehydrogenation catalyst, becomes brittle in the presence of hydrogen.
Increasing the content of nickel, rhodium or ruthenium in the alloy above 10% by weight results in an undesirable reduction in the permeability of the membrane to hydrogen.
The method according to the present invention is carried out at a temperature of from 180 to 2700C. Reducing the temperature of the process below 1 800C causes a considerable decrease in the rate of borneol dehydrogenation and in the rate of hydrogen diffusion through the membrane.
Increasing the process temperature above 2700C is undesirable from the point of view of the thermodynamic conditions in, the cyclopentadiene hydrogenation reaction.
In order that the invention may be more fully understood, the following examples are by way of illustration.
EXAMPLE 1
A flow-type reactor was divided into two noncommunicating chambers by means of a membrane in the form of a foil made of an alloy consisting of 95% by weight of palladium and 5% by weight of rhodium with a length of 1,200 mm, thickness of 0.1 mm and width of 60 mm and coiled into a double helix.
Borneol vapour was supplied to the dehydrogenation chamber in a current of argon at a rate of 4.1 mmol/hr and cyclopentadiene vapour was supplied to the hydrogenation chamber at the rate of 0.42 mmol/hr. At a temperature of 1 950C, the conversion of borneol to camphor was 68.2 mol.% and the conversion of cyclopentadiene was 3.5 mol.% at a selectivity relative to cyclopentene of 100%.
EXAMPLE2 A flow-type reactor was divided in two noncommunicating chambers by means of a membrane made of an alloy consisting of 90% by weight of palladium and 10% by weight of rhodium and having dimensions of 114 x 18 x 0.1 mm. The dehydrogenation chamber was filled with powdered copper oxide.
Borneol vapour was supplied to the dehydrogenation chamber in a current of argon at a rate of 0.21 mmol of borneol per hour, while cyclopentadiene vapour was supplied to the hydrogenation chamber in a current of argon at a rate of 0.14 mmol of cyclopentadiene per hour. At a temperature of 2000C, the conversion of borneol to camphor was 100 mol.%, and the conversion of cyclopentadiene was 5 mol.% at a selectivity relative to cyclopentene of 100%.
EXAMPLE 3
A flow-type reactor was divided into two noncommunicating compartments by a foil membrane made of an alloy consisting of 94.1% by weight of palladium and 5.9% by weight of nickel having dimensions of 114 x 18 x 0.1 mm. Iso-borneol vapour was supplied to the dehydrogenation chamber at a rate of 8.7 mmol of iso-borneol per hour, while cyclopentadiene vapour was supplied to the hydrogenation chamber in a current of argon at a rate of 0.14 mmol of cyclopentadiene per hour. At a temperature of 2420C, the conversion of iso-borneol to camphor was 1 8 mol.% and the conversion of cyclopentadiene was 5.6 mol.% at a selectivity to cyclopentene of 100%.
EXAMPLE 4
A flow-type reactor was divided into two noncommunicating compartments by a foil membrane made of an alloy consisting of 94.1% by weight oF palladium and 5.9% by weight of nickel and having dimensions of 114 x 18 x 0.1 mm. The dehydrogenation chamber was filled with pieces of copper wire. Borneol vapour was supplied to the dehydrogenation chamber in a current of argon at a rate of 4.1 mmoles of borneol per hour, while cyclopentadiene vapour was supplied to the hydrogenation chamber at a rate of 0.1 6 mmol per hour. At a temperature of 240"C, the conversion of
borneol to camphor was 49.5 mol.%, while the
conversion of cyclopentadiene was 35.3 mol.% at a selectivity relative to cyclopentene of 100%.
EXAMPLE 5
Into the dehydrogenation chamber of the flowtype reactor described in Example 4, borneol vapour was supplied in a current of argon at a rate of 4.1 mmoles of borneol per hour, and to the hydrogenation chamber, cyclopentadiene vapour was supplied in a current of argon at a rate of 0.05 mmole of cyclopentadiene per hour. At a temperature of 21 00C in the reactor, the conversion of borneol to camphor was 61.9 mol.% and the conversion of cyclopentadiene was 89.7 mol.% at a selectivity relative to cyclopentene of 82%.
EXAMPLE 6
Into the dehydrogenation chamber of the flowtype reactor described in Example 4, borneol vapour was supplied in a current of argon at a rate of 4.2 mmoles of borneol per hour, and to the hydrogenation chamber cyclopentadiene vapour was supplied at a rate of 0.06 mmol of cyclopentadiene per hour in a current of argon. At a temperature of 2090C, the conversion of borneol to camphor was 57.2 mol.% and the conversion of cyclopentadiene was 92.8 mol.% at a selectivity relative to cyclopentene of 92%.
EXAMPLE 7
A flow-type reactor was divided into two noncommunicating chambers by means of a foil membrane made of an alloy consisting of 95% by weight of palladium and 5% by weight of rhodium and having dimensions of 114 x 18 x 0.1 mm.
The dehydrogenation chamber was filled with pieces of copper wire. Borneol vapour was supplied in a current of argon to the dehydrogenation chamber at a rate of 4.1 mmoles of borneol per hour, and cyclopentadiene vapour was supplied in a current of argon to the hydrogenation chamber at a rate of 0.07 mmole of cyclopentadiene per hour. At a temperature of 2700 C, the conversion of borneol to camphor was 46.1 mol.% and the conversion of cyclopentadiene was 3.8 mol.% at a selectivity relative to cyclopentene of 100%.
EXAMPLE 8
To the dehydrogenation compartment of the flow-type reactor described in Example 7, borneol vapour was supplied in a current of argon at a rate of 4.1 mmoles of borneol per hour, and cyclopentadiene vapour was supplied in a current of argon to the hydrogenation chamber at a rate of 0.07 mmole of cyclopentadiene per hour. At a temperature of 1 800C, the conversion of borneol to camphor was 6.4 mol.% and the conversion of cyclopentadiene was 1 mol.% at a selectivity relative to cyclopentene of 100%.
EXAMPLE 9
A flow-type reactor was divided into two noncommunicating compartments by means of a foil membrane made of an alloy consisting of 90.2% by weight of palladium and 9.8% by weight of ruthenium and having dimensions of 114 x 18 x 0.1 mm. The dehydrogenation chamber was filled with pieces of copper wire.
Borneol vapour was supplied in a current of argon to the dehydrogenation chamber at a rate of 4.1 mmoles of borneol per hour, and cyclopentadiene vapour was supplied to the hydrogenation chamber at a rate of 0.07 mmole of cyclopentadiene per hour. At a temperature of 210"C, the conversion of borneol to camphor was 7.5 mol.% and the conversion of cyclopentadiene was 1.2 mol.% at a selectivity relative to cyclopentene of 100%.
EXAMPLE 10
A flow-type reactor was divided into two noncommunicating compartments by means of a foil membrane made of an alloy consisting of 92% by weight of palladium and 8% by weight of ruthenium having dimensions of 114 x 1 8 x 0.1 mm. The dehydrogenation chamber was filled with pieces of copper wire. Borneol vapour was supplied in a current of argon to the dehydrogenation chamber at a rate of 4.1 mmoles per hour, and cyclopentadiene vapour was supplied to the hydrogenation chamber at a rate of 0.07 mmol per hour. At a temperature of 2200C, the conversion of borneol to camphor was 13 mol.% and the conversion of cyclopentadiene was 4.1 mol.% at a selectivity relative to cyclopentene of 100%.
Claims (5)
1. A method for the simultaneous preparation of cyclopentene and camphor, which comprises simultaneously dehydrogenating a borneol and hydrogenating cyclopentadiene at a temperature of from 180 to 2700C in a reactor divided into two compartments by a hydrogen-permeable membrane made of an alloy consisting of 90 to 95% by weight of palladium and 10 to 5% by weight of nickel, rhodium or ruthenium, the dehydrogenation of borneol being effected in one compartment and the hydrogenation of cyclopentadiene being effected in the other by means of the hydrogen formed in the dehydrogenation and diffusing through the membrane.
2. A method according to claim 1, in which the dehydrogenation of borneol is effected in the presence of copper or copper oxide.
3. A method for the simultaneous preparation of cyclopentene and camphor substantially as herein described in any one of Examples 1 to 10.
4. Cyclopentene when produced by the method claimed in any of the preceding claims.
5. Camphor when produced by the method claimed in any of claims 1 to 3.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3003993A DE3003993C2 (en) | 1980-02-04 | 1980-02-04 | Process for the joint production of cyclopentene and camphor |
| GB8004447A GB2068938B (en) | 1980-02-04 | 1980-02-11 | Method for the simultaneous preparation of cyclopentene and camphor |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3003993A DE3003993C2 (en) | 1980-02-04 | 1980-02-04 | Process for the joint production of cyclopentene and camphor |
| GB8004447A GB2068938B (en) | 1980-02-04 | 1980-02-11 | Method for the simultaneous preparation of cyclopentene and camphor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB2068938A true GB2068938A (en) | 1981-08-19 |
| GB2068938B GB2068938B (en) | 1983-11-30 |
Family
ID=25783541
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB8004447A Expired GB2068938B (en) | 1980-02-04 | 1980-02-11 | Method for the simultaneous preparation of cyclopentene and camphor |
Country Status (2)
| Country | Link |
|---|---|
| DE (1) | DE3003993C2 (en) |
| GB (1) | GB2068938B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7211706B2 (en) * | 2001-08-03 | 2007-05-01 | Institut Francais Du Petrole | Process for recovering hydrogen in a gaseous hydrocarbon effluent using a membrane reactor |
| WO2008093898A1 (en) * | 2007-01-31 | 2008-08-07 | Kao Corporation | Reaction device |
| WO2018040666A1 (en) * | 2016-08-27 | 2018-03-08 | 福州大学 | Tubular reactor for dehydrogenation of liquid-phase alcohol and method for dehydrogenation of liquid-phase alcohol |
-
1980
- 1980-02-04 DE DE3003993A patent/DE3003993C2/en not_active Expired
- 1980-02-11 GB GB8004447A patent/GB2068938B/en not_active Expired
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7211706B2 (en) * | 2001-08-03 | 2007-05-01 | Institut Francais Du Petrole | Process for recovering hydrogen in a gaseous hydrocarbon effluent using a membrane reactor |
| WO2008093898A1 (en) * | 2007-01-31 | 2008-08-07 | Kao Corporation | Reaction device |
| US7795475B2 (en) | 2007-01-31 | 2010-09-14 | Kao Corporation | Reaction device |
| WO2018040666A1 (en) * | 2016-08-27 | 2018-03-08 | 福州大学 | Tubular reactor for dehydrogenation of liquid-phase alcohol and method for dehydrogenation of liquid-phase alcohol |
| US20190112249A1 (en) * | 2016-08-27 | 2019-04-18 | Fuzhou University | Multitubular reactor for liquid phase alcohol dehydrogenation and method for liquid phase alcohol dehydrogenation |
| US10526267B2 (en) * | 2016-08-27 | 2020-01-07 | Fuzhou University | Multitubular reactor for liquid phase alcohol dehydrogenation and method for liquid phase alcohol dehydrogenation |
Also Published As
| Publication number | Publication date |
|---|---|
| DE3003993C2 (en) | 1983-07-21 |
| DE3003993A1 (en) | 1981-08-06 |
| GB2068938B (en) | 1983-11-30 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PCNP | Patent ceased through non-payment of renewal fee |