US3714216A
Expired / Lapsed
US
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Process for preparing aromatic isocyanates
Assignee: Olin Corp
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Filing: 1967-02-28
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Granted: 1973-01-30
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Expires: 1987-02-28
Abstract
Abstract The process for preparing an organic isocyanate by reacting an organic nitro compound with carbon monoxide in the presence of a catalytic system comprised of a mixture of at least one compound selected from the group consisting of palladium halides, rhodium halides, palladium oxides, and rhodium oxides, with at least one oxide of an element selected from the group consisting of vanadium, molybdenum, tungsten, niobium, chromium, and tantalum.
Inventors
- 👤 W Schnabel
- 👤 E Kober
- 👤 T Kraus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 13:34
CPC Classifications
B; B01; B01J; B01J27/00; B01J27/06; C; C07; C07C; C07C263/00; C07C263/14
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
137 words
A process for preparing an aromatic isocyanate which comprises reacting at an elevated temperature and an elevated pressure, an aromatic nitro compound containing up to 20 carbon atoms with carbon monoxide in the presence of a catalyst system, Which comprises employing as said catalyst system a mixture of a. a compound selected from the group consisting of palladium halides, rhodium halides, palladium oxides, and rhodium oxides, and b. an oxide of an element selected from the group consisting of vanadium, molybdenum, tungsten, niobium, chromium and tantalum, c. wherein the proportion of said catalyst system is between about 0.1 and about 100 percent by weight of said aromatic nitro compound, and d. wherein sufficient carbon monoxide is present to provide at least three moles of carbon monoxide per mole of nitro groups reacted in said aromatic nitro compound.
Claim 2
Dependent Claim
137 words
A process for preparing an aromatic isocyanate which comprises reacting at an elevated temperature and an elevated pressure, an aromatic nitro compound containing up to 20 carbon atoms with carbon monoxide in the presence of a catalyst system, Which comprises employing as said catalyst system a mixture of a. a compound selected from the group consisting of palladium halides, rhodium halides, palladium oxides, and rhodium oxides, and b. an oxide of an element selected from the group consisting of vanadium, molybdenum, tungsten, niobium, chromium and tantalum, c. wherein the proportion of said catalyst system is between about 0.1 and about 100 percent by weight of said aromatic nitro compound, and d. wherein sufficient carbon monoxide is present to provide at least three moles of carbon monoxide per mole of nitro groups reacted in said aromatic nitro compound.
Claim 3
Dependent Claim
27 words
The process of claim 1 wherein the weight ratio of said compoUnd (a) to said oxide (b) is in the range between about 0: 05:1 and 10:1.
Claim 4
Dependent Claim
19 words
The process of claim 2 wherein said elevated pressure is in the range between about 100 and 8,000 psig.
Claim 5
Dependent Claim
33 words
The process of claim 2 wherein said process is carried out in the presence of an inert solvent selected from the group consisting of halogenated aliphatic hydrocarbons, halogenated aromatic hydrocarbons, and mixtures thereof.
Claim 6
Dependent Claim
19 words
The process of claim 2 wherein said elevated temperature is in the range between about 100* and 250* C.
Claim 7
Dependent Claim
16 words
The process of claim 2 wherein said aromatic nitro compound is nitrobenzene, dinitrotoluene or isocyanato nitrotoluene.
Claim 8
Dependent Claim
18 words
The process of claim 6 wherein said catalyst system is a mixture of palladium chloride and vanadium pentoxide.
Claim 9
Dependent Claim
18 words
The process of claim 6 wherein said catalyst system is a mixture of palladium chloride and molybdenum oxide.
Claim 10
Dependent Claim
18 words
The process of claim 6 wherein said catalyst system is a mixture of rhodium trichloride and vanadium pentoxide.
Claim 11
Dependent Claim
18 words
The process of claim 6 wherein said catalyst system is a mixture of rhodium trichloride and molybdenum oxide.
Claim 12
Dependent Claim
20 words
The process of claim 6 wherein said catalyst system is a mixture of rhodium trichloride, palladium chloride and vanadium pentoxide.
References Cited (Backward Citations)
BE672405A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-01-30 | 1976-07-31 | 1977-01-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-01-30 | 1980-07-31 | 1981-01-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-01-30 | 1984-07-31 | 1985-01-30 | $7700.00 | Window Closed / Lapsed |