US3662017A - Fouling reduction in oxidative dehydrogenation process - Google Patents
Fouling reduction in oxidative dehydrogenation process Download PDFInfo
- Publication number
- US3662017A US3662017A US60895A US3662017DA US3662017A US 3662017 A US3662017 A US 3662017A US 60895 A US60895 A US 60895A US 3662017D A US3662017D A US 3662017DA US 3662017 A US3662017 A US 3662017A
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- Prior art keywords
- gases
- compressor
- compounds
- gaseous
- dehydrogenation
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- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F15/00—Other methods of preventing corrosion or incrustation
- C23F15/005—Inhibiting incrustation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C11/00—Aliphatic unsaturated hydrocarbons
- C07C11/12—Alkadienes
- C07C11/16—Alkadienes with four carbon atoms
- C07C11/167—1, 3-Butadiene
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/11—Purification; Separation; Use of additives by absorption, i.e. purification or separation of gaseous hydrocarbons with the aid of liquids
Definitions
- Field of the invention relates to the mechanical compression of gaseous compositions comprising unsaturated organic compounds and carbonyl compounds.
- the process is particularly applicable to process for the purification of gases obtained by the oxidative dehydrogenation of organic compounds such as hydrocarbons.
- the dehydrogenation zone effluent from these oxidative dehydrogenation processes may be puried by a process including cooling such as by quench, waste heat boilers and the like and generally the next step is to remove a major portion of the water by condensation. Thereafter the gases are compressed in a compressor.
- cooling such as by quench, waste heat boilers and the like
- the gases are compressed in a compressor.
- considerable diiiiculty has been encountered due to fouling of the compressor cylinders, pistons and valves.
- the operation of the compressor is less efficient during build-up of the fouling because, for example, the valves will not properly open and close. Scoring of the piston and cylinder is also possible.
- FIG. l of the drawing A preferred embodiment is illustrated in FIG. l of the drawing.
- a gaseous mixture of the compound to be dehydrogenated, air and steam are fed by line 1 to the dehydrogenation zone A.
- the dehydrogenation reaction may be conducted in the absence of contact catalysts, but
- the reaction is conducted in the presence of metal or metal compound catalysts, such as disclosed in the patents cited herein.
- the dehydrogenation reactor may be a fixed or fluid bed reactor.
- the conditions of reaction may be as disclosed in any of the cited patents such as U.S. 3,334,152.
- the invention will be illustrated for the dehydrogenation of hydrocarbons but it is understood that other dehydrogenatable organic compounds may be substituted in the example.
- the effluent 2 from the dehydrogenation zone will contain the impure unsaturated hydrocarbon products, Various impurities including oxygenated hydrocarbons, noncondensable gases 1 and perhaps some unconverted hydrocarbon, oxygen and steam. When air is used as the source of oxygen, nitrogen will be present in relatively large quantities as a noncondensable gas. Steam may optionally be present in an amount up to 95 mol percent of the total effluent, such as from about 5 to 96 mole percent.
- the organic phase including dehydrogenated product, any unreacted feed, oxygenated hydrocarbons, polymer and tar and precursors thereof and any organic decomposition products usually range from about 1 to 50 mole percent of the effluent and generally will be Within the range of or about 3 to 30 or 35 mol percent of the eluent.
- the noncondensable gases, such as nitrogen or CO2 Will usually be present in an amount of vfrom about 20 to 93 mol percent of the total eluent, but more often will be Within the range of about 40 to 80 mol percent.
- the efuent gases 2 leaving the dehydrogenation zone will generally be at a temperature of about or greater than 600 F. or 700 F. to 1600 F. depending upon the particular dehydrogenation process.
- the reactor eluent may be cooled by any means or combination of means in cooling and condensation zone B as by quenching, waste heat boilers, condensers, vapor separators, and the like in any sequence.
- the major portion of any water present in the effluent will be removed as condensed steam from the gaseous effluent during this cooling and condensation operation.
- This cooled gaseous stream 3 may preferably then be compressed.
- the invention is not restricted to the particular processes prior to compression. For example, an oil quench or other step may be included.
- the gaseous composition 3 to be fed to compression will usually comprise, exclusive of any water present, about or from 3.5 to mol percent of unsaturated organic compounds such as hydrocarbon, about or from 0.0005 to 2.5 mol percent of carbonyl compounds,2 and optionally about or from 20 to 93 mol percent of noncondensable gases (i.e., noncondensable under the condition at point 3), all based on the total mols of gaseous composition 3 being fed to the compressor, exclusive of any water.
- noncondensable ygases will be any nitrogen, oxygen, CO or CO2, and the like.
- the oxygen content may vary, but suitably will be less than 10 mol percent of stream 3.
- Steam may also be present in stream 3 in an amount from 0 to 20 or up to such as 50 mol percent or more of the gaseous composition 3.
- Also present in the gaseous mixture 3 may be unconverted hydrocarbons such as oleiins or saturated hydrocarbons and hydrocarbon by-products.
- noncondensable or inert noncondensable gases refers to those gases, other than hydrocarbons such as nitrogen, CO2 land C0, which do not condense under the conditions encountered.
- a preferred composition 3 to be fed to the first stage compressor will comprise, exclusive of any water present, about or from to 65 mol precent of unsaturated hydrocarbons, about or from 0.005 to 1.2 mol percent of carbonyl compounds and about or from 45 to 89 mol percent of the noncondensable gases.
- a particularly preferred composition 3 contains about or from 8 to 65 mol percent butadiene-1,3, about or from 0.1 to 40 mol percent butene, and about or from 40 to 75 mol percent nitrogen.
- the composition of the compressed gases at 4 may be within the same ranges as given for point 3.
- Compression may be by any suitable multistage mechanical compressors such as reciprocating or centifugal compressors, with the invention being particularly suitable for reciprocating compressors.
- the invention is particularly suitable for use with double acting pistons.
- the invention is illustrated in the drawing utilizing a two stage compressor it is understood that more than two stages may be employed if desired. If more than two stages are used preferably a direct contact zone will be between the rst and second stages but may be incorporated between any stages and more than one direct contact Zone may be employed.
- Indirect cooling means may also be employed in conjunction with the direct cooling of this invention.
- Compressors conventionally employed in the recovery of butadiene-1,3 are suitable such as Clark reciprocating compressors. Preferred are compressors which have the cylinders cooled with a water jacket.
- the pressure and temperature of the gases discharging from each stage of compression will depend upon the particular compressor employed, the pressure and type of equipment downstream from the compressor, the temperature of cooling water available and the like, but typically the compressed gasses from the last stage will be at a temperature of at least 125 F. and a pressure of at least 75 p.s.i.g. but generally lthe temperature will be at least 175 F. and the pressure at least 100 p.s.1.g.
- the gases are scrub-bed in a direct contact zone.
- the scrubbing liquid will be water or an aqueous composition but other liquids which will dissolve carbonyl compounds may be used.
- the contacting zone may be any device for intimately contacting the gases with the scrubbing liquid such as packed towers, open spray towers, tray type columns and other devices for liquid-gas contact known to those skilled in the art.
- a portion of the discharge liquid is recycled to the contacting zone. It has been found that recycling of this liquid increases carbonyl removal and reduces the amount of liquid 5 which must be fed to the tower. It has been found also that recycling of the liquid increases carbonyl removal to a greater extent than would increasing the number of actual or theoretical trays in a scrubbing tower particularly when there is a limited quantity of scrubbing liquid 5.
- the recycled liquid should be cooled by at least 5 C. but normally will be cooled by at least C.
- at least l0 percent by weight and preferably atleast percent of the discharge water 6 is recycled to the direct contact zone eg. as stream 7. In terms of the water not recycled preferably the stream S will amount to at least or 50 percent by weight of the stream 6.
- the scrubbed gasses 9 are then passed to the next stage of compression and the compressed gases may be further processed as desired.
- the process of this invention may be applied to the l recovery of products produced by the dehydrogenation of a wide variety of organic compounds.
- Such compounds normally Will contain from 2 to 20 carbon atoms, at least one H H l l 4 grouping, a boiling point below about 350 C., and such compounds may contain other elements, in addition to carbon and hydrogen such as halogens, nitrogen and sulphur.
- Preferred are compounds having from 2 to 12 carbon atoms, and especially preferred are compounds of 3 to 6 or 8 carbon atoms.
- dehydrogenations include propionitrile to acrylonitrile, ethyl chloride to vinyl chloride, methyl isobutyrate to methyl methacrylate, 2-chlorobutene-l, or 2,3 dichlorobutane to chloroprene, ethyl pyridine to vinyl pyridine, ethylbenzene to styrene, isopropylbenzene to ot-methyl styrene, ethylclohexane to styrene, cyclohexane to benzene, methane to ethylene and acetylene, ethane to ethylene to acetylene, propane to propylene or methyl acetylene, allene, or benzene, isobutane to isobutylene, n-butane to butene and butadiene- 1,3, butene to butadiene-1,3 and vinyl acetylene, methyl buty
- Representative materials which are dehydrogenated by the novel process of this invention include ethyl toluene, alkyl chlorobenzenes, ethyl naphthalene, isobutyronitrile, propyl chloride, isobutyl chloride, ethyl fluoride, ethyl bromide, n-pentyl iodide, ethyl dichloride, 1,3-dichlorobutane, 1,4- dichlorobutane, the chlorotiuoroethanes, methyl pentane, and the like.
- Suitable dehydrogenation reactions are the following: acyclic compounds having 4 to 5 non-quaternary contiguous carbon atoms to the corresponding olens, diolens or acetylenes having the same number of carbon atoms; aliphatic hydrocarbons having 6 to 16 carbon atoms and at least one quaternary carbon atom to aromatic cornpounds, such as 2,4,4-trimethylpentene-1 to a mixture of xylenes; acyclic compounds having 6 to 16 carbons atoms and no quaternary carbon atoms to aromatic compounds such as n-hexane or the n-hexenes to benzene; cycloparairins and cycloolens having 5 to 8 carbon atoms to the corresponding olefin, diolein or aromatic compound, e.g., cyclohexane to cyclohexene or cyclohexadiene or benzene; aromatic compounds having 8 to l2
- the preferred compounds to be dehydrogenated are hydrocarbons with a particularly preferred class being acyclic non-quaternary hydrocarbons having 3 or 4 to 5 contiguous carbon atoms or ethyl benzene and the preferred products are n-butene-l or 2, butadiene-1,3, vinyl acetylene, Z-methyl-l-butene, 3methyllbutene, 3-methyl-Z-butene, isoprene, styrene or mixtures thereof.
- Especially preferred as feed are n-butene-l or 2 and the methyl butenes and mixtures thereof such as hydrocarbon mixtures containing these compounds in at least 50 mol percent.
- the organic compound to be dehydrogenated is contacted with oxygen in order for the oxygen to oxidatively dehydrogenate the compound.
- the oxygen may be supplied to the organic compound from any suitable source as by feeding oxygen to a dehydrogenation zone for example as disclosed in U.S. 3,207,810 issued Sept. 2l, 1965.
- Oxygen may be fed to the reactor as pure oxygen, as air, as oxygen-enriched air, oxygen mixed with diluents, and so forth.
- Oxygen may also be supplied by means of a transport or moving oxidant type of process such as disclosed in U.S. 3,050,572 issued Aug. 21, 1962 or U.S. 3,118,007 issued Jan. 14, 1964.
- oxidative dehydrogenation process when used herein means a process wherein the predominant mechanism of dehydrogenation is by the reaction of oxygen with hydrogen.
- the amount of oxygen employed may vary depending upon the desired result such as conversion, selectivity and the number of hydrogen atoms being removed. Thus, to dehydrogenate butane to butene requires less oxygen than if the reaction proceeds to produce butadiene. Normally oxygen will be supplied (including all sources, e.g. air to the reactor or solid oxidant to the reactor) in the dehydrogenation zone in an amount from about 0.2 to 1.5, preferably 0.3 to 1.2, mols per mol of H2 being liberated from the organic compound.
- the mols of oxygen supplied will be in the range of from .2 to 2.0 mols per mol of organic compound to be dehydrogenated and for most dehydrogenations this will be within the range of .25 to 1.5 mols of oxygen per mol of organic compound.
- Halogen or other additives may be present in the dehydrogenation step such as disclosed in the above cited patents, e.g., U.S. 3,334,152 issued Aug. 1, 1967. Means for separating halogen may also be incorporated in the dehydrogenation reactor or downstream.
- the reaction mixture contains a quantity of steam or diluent such as nitrogen with the range generally being between about 1 or 2 and 40 mols per mol of organic compound to be dehydrogenated.
- the temperature for the dehydrogenation reaction generally will be at least about 250 C., such as greater than about 300 C. or 375 C., and the maximum temperature in the reactor may be about 700 C. or 800 C. or perhaps higher such as 900 C. under certain circumstances. However, excellent results are obtained within the range of or about 350 C. to 700 C., such as from or about 400 C. to or about 675 C. These temperatures are measured at the maximum temperature in the dehydrogenation zone.
- FIG. 1 a hydrocarbon stream comprising butene-2 as the major component s dehydrogenated to butadiene-1,3 in reactor A.
- the feed 1 to the reactor includes air and steam.
- the effluent 2 from the reactor comprises butadiene-1,3, unreacted butene, carbonyl compounds, steam, noncondensable gaseous components such as nitrogen and various dehydrogenation byproducts such as CO2.
- the elluent is cooled and most of the water is removed in the steam condensation zone B. The gaseous stream is then compressed.
- the gaseous composition fed to the -rst stage compressor comprises by mol percent approximately a total of 67 percent noncondensable gases (mostly nitrogen, but also includes the other residual gases of air, as well as CO land CO2) and 28 percent hydrocarbons.
- the hydrocarbon portion is primarily C4s with butadiene-1,3 being the major component.
- the composition also contains 5 percent water and 815 p.p.m. acetaldehyde, 440 p.p.m. acrolein and 2 mol percent furan.
- the discharge from the rst stage compressor is at a temperature of 120 C. and a pressure of 2.62 meters of mercury.
- the discharge from the rst stage compressor is fed to the direct contact zone which is shown in FIG. 1 and for this example in more detail in FIG. 2.
- the direct contact zone in this example is a tray type scrubber having l2 plates.
- the compressor rst stage discharge 4 is fed below the trays and passes up the tower.
- Scrubbing water 5 at a temperature of 40 C. is fed to the top of the tower at a rate of 63 gallons per minute (g.p.m.).
- the scrubbing water contains approximately 38 p.p.m. of acetaldehyde and 21 p.p.m. acrolein.
- aqueous composition 6 is at a temperature of 52 C. and a portion of this is recycled to the tower.
- the composition to be recycled 7 is cooled by indirect heat exchange in the cooler and fed to the tower on the tenth tray from the top at a temperature of 42 C.
- the recycle 7 is fed at approximately 33 g.p.m. and the remainder 8 amounts to 63 g.p.m.
- the stream 8 contains minor amounts of carbon dioxide and hydrocarbons as well as 362 p.p.m. acetaldehyde and 196 p.p.m. acrolein.
- the scrubbed gases 9, taken off overhead, comprise 198 p.p.m. acetaldehyde, 103 p.p.m. acrolein and 0.02 mole percent furan and are at a temperature of 40 C. and a pressure of 2.52 meters of mercury.
- the scrubbed gases 9 amount to 448 mols per hour and are fed to the second stage of a reciprocating compressor where the gases are compressed to a pressure of 8.72 meters of mercury at a temperature of 121 C.
- the compressed gases 10 may be treated to further separate and purify the gases such as by extractive distillation, CAA extraction, fractional distillation and the like.
- gaseous compositions comprising unsaturated organic compounds and carbonyl compounds wherein the said gaseous composition is compressed with a compressor
- improvement comprising compressing the gaseous composition with a multistage compressor with direct contact scrubbing of compressed gases after at least one stage of compression with a liquid wash in a direct contacting zone with at least a portion of the discharge from the contacting zone being recycled to the contacting zone and at least a portion of the discharge from the contacting zone not being recycled to the contacting zone.
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Abstract
Description
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US6089570A | 1970-08-04 | 1970-08-04 |
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US3662017A true US3662017A (en) | 1972-05-09 |
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US60895A Expired - Lifetime US3662017A (en) | 1970-08-04 | 1970-08-04 | Fouling reduction in oxidative dehydrogenation process |
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Cited By (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20080221374A1 (en) * | 2005-01-05 | 2008-09-11 | Basf Aktiengesellschaft | Method for the Production of Propene from Propane |
US20080269536A1 (en) * | 2005-03-08 | 2008-10-30 | Basf Aktiengesellschaft | Method for Producing Propene From Propane |
US20090240094A1 (en) * | 2004-12-09 | 2009-09-24 | Basf Aktiengesellschaft Patents, Trademarks And Licenses | Method for the Production of Propene from Propane |
US20100037772A1 (en) * | 2008-08-13 | 2010-02-18 | Roe Kevin L | Apparatus and Method for Biogas Purification |
US9291409B1 (en) * | 2013-03-15 | 2016-03-22 | Rodney T. Heath | Compressor inter-stage temperature control |
WO2016046009A1 (en) * | 2014-09-26 | 2016-03-31 | Basf Se | Process for preparing 1,3-butadiene from n-butenes by oxidative dehydrogenation |
US9353315B2 (en) | 2004-09-22 | 2016-05-31 | Rodney T. Heath | Vapor process system |
US9527786B1 (en) | 2013-03-15 | 2016-12-27 | Rodney T. Heath | Compressor equipped emissions free dehydrator |
US9932989B1 (en) | 2013-10-24 | 2018-04-03 | Rodney T. Heath | Produced liquids compressor cooler |
US10052565B2 (en) | 2012-05-10 | 2018-08-21 | Rodney T. Heath | Treater combination unit |
-
1970
- 1970-08-04 US US60895A patent/US3662017A/en not_active Expired - Lifetime
Cited By (13)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US9353315B2 (en) | 2004-09-22 | 2016-05-31 | Rodney T. Heath | Vapor process system |
US20090240094A1 (en) * | 2004-12-09 | 2009-09-24 | Basf Aktiengesellschaft Patents, Trademarks And Licenses | Method for the Production of Propene from Propane |
US20080221374A1 (en) * | 2005-01-05 | 2008-09-11 | Basf Aktiengesellschaft | Method for the Production of Propene from Propane |
US20080269536A1 (en) * | 2005-03-08 | 2008-10-30 | Basf Aktiengesellschaft | Method for Producing Propene From Propane |
US20100037772A1 (en) * | 2008-08-13 | 2010-02-18 | Roe Kevin L | Apparatus and Method for Biogas Purification |
US8007567B2 (en) * | 2008-08-13 | 2011-08-30 | A & B Process Systems Corporation | Apparatus and method for biogas purification |
US8182576B2 (en) * | 2008-08-13 | 2012-05-22 | A&B Process Systems Corporation | Apparatus and method for biogas purification |
US10052565B2 (en) | 2012-05-10 | 2018-08-21 | Rodney T. Heath | Treater combination unit |
US9291409B1 (en) * | 2013-03-15 | 2016-03-22 | Rodney T. Heath | Compressor inter-stage temperature control |
US9527786B1 (en) | 2013-03-15 | 2016-12-27 | Rodney T. Heath | Compressor equipped emissions free dehydrator |
US9932989B1 (en) | 2013-10-24 | 2018-04-03 | Rodney T. Heath | Produced liquids compressor cooler |
WO2016046009A1 (en) * | 2014-09-26 | 2016-03-31 | Basf Se | Process for preparing 1,3-butadiene from n-butenes by oxidative dehydrogenation |
US10308569B2 (en) | 2014-09-26 | 2019-06-04 | Basf Se | Process for preparing 1,3-butadiene from n-butenes by oxidative dehydrogenation |
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AS | Assignment |
Owner name: PETRO-TEX CHEMICAL CORPORATION, C/O TENNECO OIL CO Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:TEXAS PETROCHEMICAL CORPORATION;REEL/FRAME:004634/0711 |
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AS | Assignment |
Owner name: TEXAS PETROCHEMICALS CORPORATION, A CORP. OF TX Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:PETRO-TEX CHEMICAL CORPORATION, A CORP. OF DE;REEL/FRAME:004748/0270 Effective date: 19870518 |
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AS | Assignment |
Owner name: TEXAS PETROCHEMICALS CORPORATION, 8707 KATY FREEWA Free format text: TERMINATION OF SECURITY AGREEMENT RECORDED JULY 25, 1986. REEL 4634 FRAME 711-723, DEBT HAS BEEN PAID;ASSIGNOR:PETRO-TEK CHEMICAL CORPORATION;REEL/FRAME:005060/0478 Effective date: 19860725 |