US4008254A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ceria catalyzed conversion of phenols to dibenzofurans in the presence of water vapor
Assignee: Monsanto Co
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Filing: 1975-08-08
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Granted: 1977-02-15
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Expires: 1995-08-08
Abstract
Abstract A method for preparation of heterocyclic fused ring compounds by dehydration and dehydrogenation of certain phenolic compounds in the presence of water vapor and in the presence of a cerium oxide catalyst is disclosed. Preferred phenolic compounds, catalytic materials, and reaction conditions also are described.
Inventors
- 👤 David E. Gross
- 👤 Norman A. Fishel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 22:46
CPC Classifications
C; C07; C07D; C07D307/00; C07D307/77; C07D307/91; B; B01; B01J; B01J23/00; B01J23/10; B01J23/12
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
119 words
Process for the production of a dibenzofuran compound which comprises contacting a phenolic compound feedstock comprising a phenol having an unsubstituted ortho position selected from phenols and polycyclic phenols having no substituents other than alkyl, hydroxy, aryl, aralkyl and alkaryl in the vapor phase in combination with water vapor at a temperature of 300° to 700° C at a gas hourly space velocity of from 1 hr.sup. -1 to 2,000 hr.sup. -1 with a catalyst essentially composed of a member of the class of ceria and combinations of ceria with an oxide of a metal of the group consisting of aluminum, silicon, titanium, zirconium, hafnium, magnesium, calcium, potassium, sodium, lanthanum, neodymium, praseodymium, samarium, thorium, and uranium and mixtures thereof.
Claim 2
Dependent Claim
119 words
Process for the production of a dibenzofuran compound which comprises contacting a phenolic compound feedstock comprising a phenol having an unsubstituted ortho position selected from phenols and polycyclic phenols having no substituents other than alkyl, hydroxy, aryl, aralkyl and alkaryl in the vapor phase in combination with water vapor at a temperature of 300° to 700° C at a gas hourly space velocity of from 1 hr.sup. -1 to 2,000 hr.sup. -1 with a catalyst essentially composed of a member of the class of ceria and combinations of ceria with an oxide of a metal of the group consisting of aluminum, silicon, titanium, zirconium, hafnium, magnesium, calcium, potassium, sodium, lanthanum, neodymium, praseodymium, samarium, thorium, and uranium and mixtures thereof.
Claim 3
Dependent Claim
92 words
Process for the production of dibenzofuran which comprises contacting phenol in the vapor phase in combination with water vapor at a temperature of 300° C to 700° C at a gas hourly space velocity of from 1 hr.sup. -1 to 2,000 hr.sup. -1 over a catalyst essentially composed of a member of the class of ceria per se, and combinations of ceria with an oxide of a metal of the group consisting of aluminum, silicon, magnesium, titanium, zirconium, hafnium, calcium, potassium, sodium, lanthanum, neodymium, praseodymium, samarium, thorium, and uranium and mixtures thereof.
Claim 4
Dependent Claim
92 words
Process for the production of dibenzofuran which comprises contacting phenol in the vapor phase in combination with water vapor at a temperature of 300° C to 700° C at a gas hourly space velocity of from 1 hr.sup. -1 to 2,000 hr.sup. -1 over a catalyst essentially composed of a member of the class of ceria per se, and combinations of ceria with an oxide of a metal of the group consisting of aluminum, silicon, magnesium, titanium, zirconium, hafnium, calcium, potassium, sodium, lanthanum, neodymium, praseodymium, samarium, thorium, and uranium and mixtures thereof.
Claim 5
Dependent Claim
28 words
Process as in claim 1 in which the water vapor is present in the proportion of from 0.01 to equal proportion by weight to the phenolic compound feedstock.
Claim 6
Dependent Claim
26 words
Process as in claim 2 in which the water vapor is present in the proportion of from 0.01 to equal proportion by weight to the phenol.
Claim 7
Dependent Claim
11 words
Process as in claim 2 in which the catalyst is ceria.
Claim 8
Dependent Claim
15 words
Process as in claim 5 in which the ceria is dispersed on an alumina carrier.
Claim 9
Dependent Claim
15 words
Process as in claim 5 in which the ceria is dispersed on a silica-alumina carrier.
Claim 10
Dependent Claim
15 words
Process as in claim 5 in which the ceria is in combination with potassium oxide.
Claim 11
Dependent Claim
15 words
Process as in claim 5 in which the ceria is in combination with thorium oxide.
Claim 12
Dependent Claim
20 words
Process as in claim 1 in which the feedstock is orthophenylphenol, and the product is a diphenyl derivative of dibenzofuran.
Claim 13
Dependent Claim
18 words
Process as in claim 1 in which the feedstock is resorcinol, and the products are 1,7-dihydroxydibenzofuran and 3,7-dihydroxydibenzofuran.
Claim 14
Dependent Claim
16 words
Process as in claim 1 in which the feedstock is 1-naphthol, and the product is dinaphthofuran.
Claim 15
Dependent Claim
16 words
Process as in claim 1 in which the feedstock is paracresol, and the product is 2,8-dimethyldibenzofuran.
Claim 16
Dependent Claim
14 words
Process as in claim 1 in which hydrogen is added to the reaction mixture.
Claim 17
Dependent Claim
31 words
Process as in claim 1 in which the catalyst is periodically regenerated by passing an oxygen containing gas over the catalyst at a temperature of from 300° C to 1000° C.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-02-15 | 1980-08-16 | 1981-02-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-02-15 | 1984-08-16 | 1985-02-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-02-15 | 1988-08-16 | 1989-02-15 | $7700.00 | Window Closed / Lapsed |