USRE30430E - Catalyst treatment - Google Patents
Catalyst treatment Download PDFInfo
- Publication number
- USRE30430E USRE30430E US06/014,833 US1483379A USRE30430E US RE30430 E USRE30430 E US RE30430E US 1483379 A US1483379 A US 1483379A US RE30430 E USRE30430 E US RE30430E
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- US
- United States
- Prior art keywords
- molybdenum
- compound
- catalyst
- process according
- iaddend
- Prior art date
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Classifications
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- 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
- B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
- B01J37/28—Phosphorising
-
- 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
- B01J23/90—Regeneration or reactivation
- B01J23/92—Regeneration or reactivation of catalysts comprising metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/16—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation
- C07C51/31—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation of cyclic compounds with ring-splitting
- C07C51/313—Preparation of carboxylic acids or their salts, halides or anhydrides by oxidation of cyclic compounds with ring-splitting with molecular oxygen
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/584—Recycling of catalysts
Definitions
- This invention relates to improvements in the preparation of dicarboxylic acid anhydrides by the vapor phase oxidation of hydrocarbons and more particularly relates to improvements in the process for the catalytic oxidation of hydrocarbons to dicarboxylic anhydrides in the presence of a vanadium-molybdenum-oxygen catalyst.
- the present invention is the discovery that vanadium-molybdenum-oxygen catalysts may be reactivated and stabilized by adding to the catalyst, compounds of molybdenum, nickel, cobalt, manganese, or uranium and mixtures thereof. More particularly, volatile or volatizable compounds of molybdenum, nickel, cobalt, manganese, uranium or mixtures, are preferably employed.
- organometallic compounds and inorganic compounds of Mo, Ni, Co, Mn and U may be used according to the present invention.
- Suitable organometallic compounds include molybdenum acetylacetonate, mesitylenemolybdenum tricarbonyl, nickel dimethyl glyoxime, dicyclopentadienyl nickel, cobalt (II) formate, (tert-butylcyclopentadienyl) manganese tricarbonyl, (ditert-butylcyclopentadienyl) manganese tricarbonyl, uranium (V) ethoxide, uranium isopropoxide and the like.
- inorganic compounds which are suitable for the present invention including molybdenum dibromide, molybdenum tetrabromide, molybdenum tribromide, molybdenum carbonyl, molybdenum pentachloride, molybdenum tetrachloride, molybdenum trichloride, molybdenum hexafluoride, molybdenum oxytetrachloride, molybdenum oxytrichloride, molybdenum oxytrichloride, molybdenum oxypentachloride, molybdenum oxytetrafluoride, nickel acetate, nickel carbonyl, nickel nitrate hexahydrate, cobalt nitrosyl carbonyl, manganese nitrate, uranium hexafluoride, uranium tribromide, uranyl nitrate and the like.
- Suitable Mo, Ni, Co, Mn and U compounds will generally have a boiling or volatilization temperature of no greater than 250° C. and preferably no greater than 200° C.
- the volatilized Mo, Ni, Co, Mn or U compound is preferably added to the hydrocarbon reaction stream being fed over the vanadium - molybdenum - oxygen catalyst.
- the regeneration process of the present invention may be initiated at any time a decline in the activity of the catalyst is noted, usually by a decline in the yield from the process or an increase in the temperature of the hot spot in the catalyst bed.
- An increase in the temperature of the hot spot may require reduction in the hydrocarbon throughput, thereby also reducing the unit yield.
- vanadium-molybdenum-oxygen catalysts are well known and have been described and used for the preparation of maleic anhydride in numerous patents; for example, U.S. Pat. Nos. 1,636,857; 2,294,130; 2,674,582; 2,885,409; 2,967,185; 3,074,969; 3,163,613; and 3,211,671.
- the vanadium-molybdenum-oxygen catalysts to be reactivated according to the present invention appear to comprise vanadium, molybdenum and oxygen combined in a complex.
- Suitable catalyst may have overall atomic ratios of molybdenum to vanadium in the range of 0.05 to 0.95:1.
- the vanadium-molybdenum-oxygen catalyst may contain various stabilizers and modifiers such as nickel, cobalt, iron, manganese, phosphorus, and alkali and alkaline earth metals, generally in percents of less than 25 weight percent based on the total weight of vanadium and molybdenum.
- the vanadium-molybdenum-oxygen catalyst may be modified with 0.002 to 0.1 atom of nickel, 0.0053 to 1.106 atom of cobalt, 0.0072 to 0.30 atom of iron, 0.0003 to 0.12 atom of phosphorus and/or 0.011 to 0.76 atom of lithium, sodium, potassium, calcium or strontium per atom of vanadium.
- the atomic ratio of oxygen to the remaining components of the catalyst, when the catalyst is in the process of being used to catalyze the oxidation is difficult to determine and is probably not constant due to the competing reactions of oxidation and reduction taking place during the reaction at high temperatures.
- the overall ratio of oxygen to the combined atoms of vanadium and molybdenum at room temperature would be such as about 4 to 10 atoms of oxygen per the combined atoms of vanadium and molybdenum.
- the catalyst is present during the reaction as an oxide of vanadium and molybdenum.
- the vanadium-molybdenum-oxygen catalyst may be prepared in a number of ways, as shown in the art.
- the catalyst may be prepared by precipitating the vanadium and molybdenum compound, either with or without a carrier, from a colloidal dispersion of the ingredients in an inert liquid.
- the catalyst may also be prepared by dissolving vanadium and molybdenum compounds in a common solvent, such as hot oxalic acid and thereafter depositing the solution on a carrier. In some instances, the catalyst may be deposited as molten metal compounds on a carrier; however, care must be taken not to vaporize off any of the ingredients.
- the catalyst may also be prepared by heating and mixing anhydrous forms of molybdenum acids with vanadium compounds.
- the desired amount of molybdenum oxide is introduced by dissolving ammonium molybdate in concentrated hydrochloric acid. Then, the desired amount of ammomium vanadate was dissolved in the solution. The other components, if any, are dissolved in the acid solution, for example, cobalt nitrate, nickel nitrate, sodium chloride, trisodium phosphate and the like.
- the resulting solution of the mixture of compounds is mixed with granules of ceramically bonded, fused porous alumina, and subjected to evaporation, resulting in the deposition of the catalytic materials on the surface in the pores of the support or carrier.
- the catalyst-carrier is then calcined in the presence of air in a kiln held at a constant temperature of 650°-800° F.
- the process of oxidation described herein is applicable generally to processes for the oxidation of hydrocarbons, e.g., having four to eight carbon atoms, to dicarboxylic .[.acids.]. .Iadd.anhydrides .Iaddend.in the presence of vanadium-molybdenum-oxygen catalysts.
- the process is particularly applicable to processes for the preparation of maleic anhydride, from C 4 hydrocarbons and benzene, and especially the preparation of maleic anhydride from benzene, .[.terephthalic.]. .Iadd.phthalic .Iaddend.anhydride from ortho xylene and paraphthalic anhydride from paraxylene.
- the oxidation of the hydrocarbon to aliphatic dicarboxylic anhydrides may be accomplished by contacting low concentrations of hydrocarbon in oxygen in contact with the vanadium-molybdenum-oxygen catalyst.
- Air is the most economical source of oxygen, but mixtures of oxygen and diluent gases, such as nitrogen may also be employed. Air streams enriched with oxygen may also be used.
- the gaseous feed stream to the reactor normally will contain about 1.1 to about 1.6 mol percent hydrocarbons based on the total gaseous stream. About 1.25 to about 1.5 mol percent of the hydrocarbon generally gives optimum output of product, although higher and lower concentrations may be utilized.
- the flow rate of the gaseous stream to the reactor may be varied within fairly wide limits, but a preferred range is at the rate of about 50 to 200 grams of hydrocarbon per liter of catalyst per hour, and generally will be within the range of about 75 to 150 grams of hydrocarbon per liter of catalyst per hour.
- Residence time of the gas stream will normally be less than about 5 seconds, such as from about 0.01 to less than 2 seconds. The best results have been obtained at residence times of less than 1 second.
- the flow rates and residence times are calculated at standard conditions of 760 mm. of mercury and at 25° C. The preferred hydrocarbon feed in benzene.
- the temperature of reaction for the oxidation of the hydrocarbon to dicarboxylic anhydrides may be varied.
- the temperature of reaction will depend to some extent upon the size of the reactor, the hydrocarbon concentration and the particular vanadium-molybdenum-oxygen catalyst being employed.
- a suitable temperature of reaction is from about 340° to about 500° C., as measured at the maximum temperature in the reactor. Better results have been obtained at temperatures from 360° to 475° C.
- the pressure on the reactor is not generally critical, and the reaction may be conducted at atmospheric, superatmospheric, or below atmospheric pressure.
- the oxidation of the hydrocarbons to dicarboxylic anhydrides in the presence of a vanadium-molybdenum-oxygen catalyst may be conducted in a variety of reactors.
- Fixed bed reactors used for the production of maleic anhydride are quite satisfactory.
- Multiple tube heat exchanger type reactors have been successfully used. Because the reaction is exothermic, the heat generated must be conducted away from the reactor. Normally, the reactors contain a preheat zone of an inert material.
- Catalyst support may be used to give the catalyst physical strength and stability.
- the carrier may vary in size but generally is from about 21/2 mesh to about 10 mesh in the Tyler Standard Screen Size.
- Useful carriers are such as the inert alumina carriers or the silicon carbides.
- the amount of the vanadium-molybdenum-oxygen catalysts on the carrier is usually in the range of about 10 to about 35 weight percent of the total weight of complex plus carrier.
- the final particle size of the catalyst particles will also preferably be about 21/2 to about 10 mesh size.
- the final catalyst particles may be of a variety of shapes, with the preferred shape being the shape of cylinders or spheres or irregular spheres.
- Inert diluents such as silica may be present in the catalytic surface, but the combined weight of the vanadium, molybdenum and oxygen will preferably be at least 50 weight percent of the catalytic surface.
- the activating compounds can be added to the vanadium-molybdenum-oxygen catalysts in a number of different ways.
- the vanadium-molybdenum-oxygen catalyst will first be used for the oxidation of hydrocarbons to dicarboxylic anhydride for a period of time until the yield of dicarboxylic anhydride diminishes.
- the molybdenum compound may then be added to reactivate the catalyst.
- the reactivation step may be accomplished either with or without the flows of hydrocarbon and/or oxygen continued.
- a preferred method for the reactivation of the vanadium-molybdenum-oxygen catalyst is by the continuous or intermittent addition of volatile inorganic molybdenum compound to the gaseous stream of hydrocarbons and oxygen-containing gases entering the reactor.
- the activity of the vanadium-molybdenum-oxygen catalyst is maintained through continuous reactivation or stabilization.
- Still another method for the addition of the molybdenum compound to the vanadium-molybdenum-oxygen catalyst is by the addition of the molybdenum compound in liquid phase by pouring the molybdenum compound over the catalyst to be reactivated. Reactivation by this technique may suitably be performed at about room temperature if desired.
- the molybdenum compound may be added to the vanadium-molybdenum-oxygen catalyst by a variety of methods such as adding the molybdenum compound as a liquid or gas. Other techniques such as the use of an aerosol to convey the molybdenum compound are also satisfactory. Suspensions or colloidal solutions of the molybdenum compounds may be employed. Solvents for the molybdenum compound may be included.
- the molybdenum compound may be added such as to the hydrocarbon, the oxygen containing gas or via a diluent gas such as nitrogen.
- the overall temperature range for the addition of the molybdenum compound suitably will be from about 0° to 600° C., depending upon the particular compound selected.
- the preferred temperature of the vanadium-molybdenum-oxygen catalyst at the time of addition of the molybdenum compound will be at least 325° C. with still better results being obtained at a catalyst temperature of at least 375° C.
- the upper limits of the temperature of the catalyst during reactivation will suitably be about 450° or 500° C., or perhaps higher for momentary periods of time.
- the pressure during the addition may be atmospheric, sub-atmospheric or super-atmospheric. The conditions of concentration, temperature and pressure should be adjusted to permit optimum contact of the molybdenum compound with the vanadium-molybdenum-oxygen catalyst.
- the amount of molybdenum compound added may be varied depending upon such factors as the age of the catalyst, the temperature at which the catalyst has been operated, the composition of the vanadium-molybdenum-oxygen catalyst and so forth.
- the quantity is generally relatively small such as at least about 0.000005 mol of molybdenum compound added per gram atom of vanadium in the catalyst per day, such as at an average rate of 0.00002 gram mol per day per gram atom of vanadium, or based on the hydrocarbon entering the reactor about 0.0000001 to 0.00001 mol of the molybdenum compound per mol of hydrocarbon.
- Preferred amounts are about 0.000001 to 0.000008 mol of the molybdenum compound per mol of the hydrocarbon such as benzene.
- the addition may be either intermittent or continuous. Of course, even if the molybdenum compound is added continuously, it is not necessary that it be added at a constant rate.
- the deactivated catalyst particles are selectively activated.
- Another advantage of the invention is that a fixed catalyst bed containing a preheat zone of inert particles may be activated without removing the preheat zone or the catalyst particles from the reactor. The reactivation procedure does not cause the catalyst bed to be plugged.
- the activating compound is added to the hydrocarbon flow intermittently in the amount of 0.000002 to 0.0002 gram mole of molybdenum, nickel, cobalt, manganese or uranium compound (or mixtures) per gram mole of vanadium in the catalyst and more preferably in the amount of 0.00001 to 0.0001 gram mole per gram mole of vanadium.
- the present invention may be employed with a vanadium-molybdenum-oxygen catalyst which has been pretreated with a phosphorus compound prior to the Mo, Ni, Co, Mn or U activator-regenerator treatment. It is believed that the phosphorus compound selectively deactivates some portions of the catalyst to a very slight extent, in a manner, beneficial to the subsequent reactivation with inorganic molybdenum, nickel, cobalt, manganese or uranium compounds.
- Suitable phosphorus compounds are phosphorus halides of the structure PX n ' wherein X' is Cl, Br, I or F and n is 3-5 or an organophosphorus compound selected from the group consisting of ##STR1## wherein R is phenyl or an alkyl radical of one to 6 carbon atoms and X is H or R. Sulphur may be substituted for oxygen in any of these formulas.
- Suitable compounds are such as the primary, RPH 2 , secondary, R 2 PH, and tertiary, R 3 P, phosphines such as ethyl phosphine; the tertiary phosphine oxides, R 3 PO, such as tripropyl phosphine oxide; and primary, RP(O) (OX) 2 , and secondary, R 2 P(O)OX, phosphonic acids such as benzene phosphonic acid; the esters of the phosphonic acids such as diethyl methane-phosphonate; the phosphonous acids, RPO 2 X 2 , such as benzene-phosphonous acid and the esters thereof such as the monoethyl ester; the phosphonous acids, R 2 POX, such as diethyl phosphonous acid and the esters thereof such as the monoethyl ester; the primary, ROP(OX) 2 , secondary, (RO) 2 POX, and tertiary, (RO
- Suitable phosphorous compounds are such as phosphorus trichloride, phosphorus trifluoride, phosphorus dichloride monofluoride, phosphorus tribromide, phosphorus dibromide trichloride, phosphorus dibromide trifluoride, phosphorus triiodide, phosphorus pentachloride, the diphosphorus halides, e.g., phosphorus dichloride (P 2 Cl 4 ), phosphorus diiodide (P 2 I 4 ), the primary, RPH 2 , secondary, R 2 PH, and tertiary, R 3 P, phosphines such as ethyl phosphine; the tertiary phosphine oxides, R 3 PO, such as tripropyl phosphine oxide; the primary, RP(O)(OX) 2 , and secondary, R 2 P(O)OX, phosphonic acids such as benzene phosphonic acid; the esters of the
- Preferred phosphorus compounds are those wherein the phosphorus has a valence of less plus five.
- the phosphorus compounds will suitably have a boiling point of no greater than 250° C. and preferably will have a boiling point of no greater than 200° C. and may be added to the vanadium-molybdenum-oxygen catalyst by the same means as the Mo, Ni, Co, Mn or U compounds as described above.
- the phosphorus compound may be added up to 0.0012 gram mole per gram mole of vanadium in the vanadium-molybdenum-oxygen catalyst and generally in the range of 0.00004 to 0.0008 gram mole per gram mole of vanadium.
- the phosphorus compound used is preferably one which is volatile or will volatilize under the conditions of addition to the hydrocarbon flow, such as, trimethyl phosphite, phosphorus trichloride, triethyl thiophosphate, phosphorus pentafluoride and phosphorus dichloride monofluoride.
- Benzene was oxidized to maleic anhydride in a 1.06 inch carbon steel, twelve foot long reactor.
- the reactor was cooled by a salt bath.
- a mixture of 1.35 mol percent benzene in air was fed to the reactor.
- the flow rate was 92.4 grams of benzene per liter of catalyst per hour.
- the catalyst comprised an oxide of vanadium and molybdenum.
- the actives were supported on an inert carrier.
- the catalyst gave a maximum yield of 88.2 weight percent maleic anhydride after 1400 hours at a throughput of 9.06 pounds of benzene per tube per day.
- the reactor temperature at this time was maintained in the range of 360° to 410° C.
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- Organic Chemistry (AREA)
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Abstract
Description
Claims (13)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/014,833 USRE30430E (en) | 1979-02-26 | 1979-02-26 | Catalyst treatment |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/014,833 USRE30430E (en) | 1979-02-26 | 1979-02-26 | Catalyst treatment |
Related Parent Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US05/563,740 Reissue US4006168A (en) | 1975-03-31 | 1975-03-31 | Catalyst treatment |
Publications (1)
Publication Number | Publication Date |
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USRE30430E true USRE30430E (en) | 1980-11-04 |
Family
ID=21768008
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/014,833 Expired - Lifetime USRE30430E (en) | 1979-02-26 | 1979-02-26 | Catalyst treatment |
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Country | Link |
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US (1) | USRE30430E (en) |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4515899A (en) | 1983-12-14 | 1985-05-07 | Denka Chemical Corporation | Steam regeneration of phosphorus treated vanadium-phosphorus-oxygen catalysts |
US4536483A (en) | 1982-10-26 | 1985-08-20 | Nitto Chemical Industry Co., Ltd. | Process for regeneration of iron-antimony metallic oxide catalysts |
US4701433A (en) | 1985-05-22 | 1987-10-20 | Amoco Corporation | Process for improving phosphorus-vanadium oxide and phosphorus-vanadium-co-metal oxide catalysts |
US4757038A (en) | 1982-10-26 | 1988-07-12 | Nitto Chemical Industry Co., Ltd. | Regeneration of iron-antimony metallic oxide catalysts |
US5521134A (en) * | 1994-02-22 | 1996-05-28 | Scientific Design Company, Inc. | Method for regenerating vanadium/phosphorus oxidation catalysts |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2885409A (en) * | 1957-05-27 | 1959-05-05 | American Cyanamid Co | Maleic anhydride production and catalyst therefor |
US3074969A (en) * | 1959-05-12 | 1963-01-22 | Pittsburgh Plate Glass Co | Method of preparing maleic anhydride |
US3236782A (en) * | 1962-09-26 | 1966-02-22 | Du Pont | Process regeneration of mixed metallic oxide catalysts by contacting with metal compound vapor |
US3882159A (en) * | 1973-08-20 | 1975-05-06 | Standard Oil Co | Reactivation of molybdenum containing oxidation catalysts in fluid bed reactors |
-
1979
- 1979-02-26 US US06/014,833 patent/USRE30430E/en not_active Expired - Lifetime
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2885409A (en) * | 1957-05-27 | 1959-05-05 | American Cyanamid Co | Maleic anhydride production and catalyst therefor |
US3074969A (en) * | 1959-05-12 | 1963-01-22 | Pittsburgh Plate Glass Co | Method of preparing maleic anhydride |
US3236782A (en) * | 1962-09-26 | 1966-02-22 | Du Pont | Process regeneration of mixed metallic oxide catalysts by contacting with metal compound vapor |
US3882159A (en) * | 1973-08-20 | 1975-05-06 | Standard Oil Co | Reactivation of molybdenum containing oxidation catalysts in fluid bed reactors |
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4536483A (en) | 1982-10-26 | 1985-08-20 | Nitto Chemical Industry Co., Ltd. | Process for regeneration of iron-antimony metallic oxide catalysts |
US4757038A (en) | 1982-10-26 | 1988-07-12 | Nitto Chemical Industry Co., Ltd. | Regeneration of iron-antimony metallic oxide catalysts |
US4515899A (en) | 1983-12-14 | 1985-05-07 | Denka Chemical Corporation | Steam regeneration of phosphorus treated vanadium-phosphorus-oxygen catalysts |
US4701433A (en) | 1985-05-22 | 1987-10-20 | Amoco Corporation | Process for improving phosphorus-vanadium oxide and phosphorus-vanadium-co-metal oxide catalysts |
US5521134A (en) * | 1994-02-22 | 1996-05-28 | Scientific Design Company, Inc. | Method for regenerating vanadium/phosphorus oxidation catalysts |
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