Classifications

• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2/00—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms
  • C07C2/02—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition between unsaturated hydrocarbons
  • C07C2/04—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition between unsaturated hydrocarbons by oligomerisation of well-defined unsaturated hydrocarbons without ring formation
  • C07C2/06—Preparation of hydrocarbons from hydrocarbons containing a smaller number of carbon atoms by addition between unsaturated hydrocarbons by oligomerisation of well-defined unsaturated hydrocarbons without ring formation of alkenes, i.e. acyclic hydrocarbons having only one carbon-to-carbon double bond
  • C07C2/08—Catalytic processes
  • C07C2/14—Catalytic processes with inorganic acids; with salts or anhydrides of acids
  • C07C2/20—Acids of halogen; Salts thereof ; Complexes thereof with organic compounds
• • 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
  • B01J27/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
  • B01J27/28—Regeneration or reactivation
  • B01J27/32—Regeneration or reactivation of catalysts comprising compounds of halogens
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2521/00—Catalysts comprising the elements, oxides or hydroxides of magnesium, boron, aluminium, carbon, silicon, titanium, zirconium or hafnium
  • C07C2521/06—Silicon, titanium, zirconium or hafnium; Oxides or hydroxides thereof
  • C07C2521/08—Silica
• • C—CHEMISTRY; METALLURGY
  • C07—ORGANIC CHEMISTRY
  • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
  • C07C2527/00—Catalysts comprising the elements or compounds of halogens, sulfur, selenium, tellurium, phosphorus or nitrogen; Catalysts comprising carbon compounds
  • C07C2527/06—Halogens; Compounds thereof
  • C07C2527/08—Halides
  • C07C2527/12—Fluorides
  • C07C2527/1213—Boron fluoride
• • 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

• An alpha-olefin is oligomerized in the presence of a threes-component catalyst comprising boron trifluoride, a minute amount of water and a particulate adsorbent material such as silica to a product predominating in those oligomer fractions having viscosities within the lubricating oil range such as the trimer and tetramer of " 1-decene.
• a threes-component catalyst comprising boron trifluoride, a minute amount of water and a particulate adsorbent material such as silica to a product predominating in those oligomer fractions having viscosities within the lubricating oil range such as the trimer and tetramer of " 1-decene.
• the oligomer mixtures produced from certain 1-olefins, that have been polymerized using boron tri ⁇ fluoride as the catalyst/ have been useful as base fluids for preparing lubricants, hydraulic fluids, transmission fluids, transformer fluids and the like, generically designated by the term functional fluids.
• the oligomer products of 1-olefins having from four to 12 carbon atoms or mixtures of these have been described as useful for preparing these functional fluids with the oligomer product of 1-decene being particularly preferred in current usage.
• the functional fluids that have been prepared from 1-decene for use in motor oils contain various proportions of the trimer, tetramer and pentamer fractions, the diraer having been removed because it possesses significant volatility and low viscosity.
• this 20-carbon oligomer can be useful as a functional fluid in specific applications.
• the use of a promoter or co-catalyst with the boron trifluoride has been conventional in order to obtain useful catalytic activity for the boron trifluoride.
• the co-catalyst complexes with the boron trifluoride to form a coordina ⁇ tion compound which is catalytically active for the oligomerization reaction.
• aliphatic ethers such as dimethyl ether and diethyl ether
• aliphatic alcohols such as methanol, ethanol, n-butanol and decanol
• polyols such as ethylene glycol and glycerol
• water aliphatic carboxylic acids, such as acetic acid, propanoic acid and butyric acid
• esters such as ethyl acetate and methyl propionate
• ketones such as acetone
• aldehydes such as acetaldehyde and benzaldehyde and acid anhydrides, such as acetic acid anhydride and succinic anhydride.
• a particulate solid adsorbent is utilized in the oligomerization reactor as one of the components comprising our three-component catalyst system.
• This solid adsorbent can be positioned in the reactor as a bed for flow-through contact with the reaction liquid or it can be maintained as a slurry in the reaction liquid by suitable agitation in a batch or continuous reaction.
• the reaction vessel is pressured with boron tri- fluoride, the second component of our catalyst system, a substantial quantity of the boron trifluoride is adsorbed by the solid adsorbent to form an active oligomerization catalyst.
• boron trifluoride readily desorbs from the solid adsorbent, a suitable boron trifluoride pressure and a suitable concentration of boron trifluoride in the reaction liquid is maintained during the oligomerization reaction to insure that the catalytically active solid adsorbent-boron trifluoride combination is maintained throughout the course of the oligomerization reaction.
• this two- component catalyst comprising the solid adsorbent and the boron trifluoride gradually loses activity after a period of continued use, which aging cannot be conveniently corrected by increasing the boron tri ⁇ fluoride pressure.
• this catalyst aging is the result of gradual physical and chemical changes in the solid adsorbent-boron trifluoride catalyst as it is being used. Unexpectedly, we have discovered that this aging can .essentially be prevented if a minute amount of water is fed to the reactor in. the 1-olefin feed. This water is also adsorbed by the solid adsorbent to form the three-component catalyst system of our invention.
• the process can be operated at a greater throughput of the 1-olefin feed as determined by the liquid hourly space velocity.
• Another benefit in this greater catalyst activity is that the process can be operated with less boron trifluoride in the catalyst and therefore less boron trifluoride fed to the reactor.
• the beneficial results that are obtained in our process by the use of water in association with the solid adsorbent and boron tri ⁇ fluoride catalyst components are obtained within the solubility limits of the water in the 1-olefin.
• the upper solubility limit of water in 1-decene is from 100 to 130 ppm. (parts by weight of water per million parts by weight of 1-decene) at 25°C.
• an upper limit of 40 or 50 ppm. water in the olefin feed is all that is generally necessary to obtain the full benefits of the three-component catalyst systeir. in the oligomerization reaction.
• a minimum amount of water is necessary in order for its use to be advantageous.
• the 1-olefin feed contains about five ppm. water it is preferred that the feed olefin contain at least about ten ppm. water for significant improvement and at least 20 or 25 ppm. water is desired .for substantial improve ⁇ ment in conversion and maintenance of catalyst activity.
• 1-decene is the most preferred alpha-olefin for preparing synthetic lubricants and related functional fluids by our novel process.
• 1-olefins having from three to 12 carbon atoms and preferably eight to 12 carbon atoms or various combinations of these alpha- olefins can also be used.
• the straight chain olefins are preferred, however branched chain 1-olefins can comprise a portion or all of the 1-olefin feed.
• a potentially significant result in varying the molecular structure of the 1-olefin is an effect on the properties of the resulting oligomer, including the viscosity, pour point and volatility, and it is for this reason that the straight chain 1-olefins are preferred.
• this lower olefin be co-oligomerized with at least about 20 mol percent of one or more of the higher .olefins in order to obtain the desired oligomer mixture.
• the lubricating oil range to which our process is directed varies between about 20 and about 50 carbon atoms, and more particularly between about 24 and 42 carbon atoms, and most preferably about 30 to about 40 carbon atoms.
• Our process is therefore preferably carried out under appropriate con ⁇ ditions to obtain the maximum oligomer selectivity within the desired range of carbon numbers.
• One of the particular benefits of our three-component catalyst system is that high product selectivity within the lubricating oil range is readily obtained and under appropriate conditions the selectivity is even enhanced.
• oligomer fractions having about 50 carbon atoms and higher Since it is difficult to separate or even.determine by analysis the different oligomer fractions having about 50 carbon atoms and higher, reference herein to an oligomer fraction having about 50 carbon atoms is intended to include the possible presence of minor amounts of one or more oligomer fractions having a higher number of carbon atoms.
• any solid adsorbent material, inorganic or organic which has a surface area of at least about 0.1 m 2 /g. and which is insoluble in the reaction liquid can be used as the solid adsorbent in our process.
• the class of inorganic adsorbents include silica, the silica-aluminas, silica- zirconia, silica-magnesia, silica-thoria, alumina, magnesia, zirconia, activated carbon, the zeolites, silicon carbide, silicon nitride, titania, aluminum-aluminum phosphate, zirconium phosphate, thoria, the magnesia-aluminas such as magnesium aluminate, zinc aluminate, pumice, naturally occurring clays, such as diatomaceous earth, and the like.
• the class of organic adsorbents includes porous polyvinyl alcohol beads, porous polyethylene glycol beads, the macroreticular acid cation exchange resins, such as the sulfonated styrene-divinylbenzene copolymer exchange resins (for example, Amberlyst-15 and Amberlite-XN1040 supplied by Rohm and Haas Company, Philadelphia, Pa.), and the like.
• the macroreticular acid cation exchange resins such as the sulfonated styrene-divinylbenzene copolymer exchange resins (for example, Amberlyst-15 and Amberlite-XN1040 supplied by Rohm and Haas Company, Philadelphia, Pa.), and the like.
• silica or a composition compris ⁇ ing at least about 50 percent silica as the solid adsorbent.
• the three-component catalyst is preferably used as a fixed bed of relatively uniformly sized particles in * a flow-through reactor.
• the exter ⁇ nal surface area of the catalyst is a more significant factor with regard to catalyst activity than its pore volume.
• the particle size can be of particular significance.
• the particle size of the catalyst is preferably at least about 100 mesh (0.15 mm.) in particle size, and most preferably at least about 50 mesh (0.3 mm.).
• the maximum particle size is preferably about 3 mesh (6.-7 mm.) and most preferably about 10 mesh (2.0 mm.).
• useful oligomer products can be prepared with solid adsorbent outside these limits of particle size.
• the reaction temperature also exerts a significant effect on the reaction. As the temperature increases at constant contact time, both the conversion and the selectivity to oligomers higher than the dimer decreases while the amount of the dimer increases. For this reason it is desirable that the maximum reaction temperature be about 150° C. , preferably no higher than about 100° C. and most preferably no higher than about 50° C. On the other hand although the reaction can be carried out at a temperature as low as about -50° C, it is preferred that the minimum operating, temperature be at least about -10° C.
• reaction temperature affects the solubility of the boron trifluoride in the reaction liquid and also affects the adsorption of both the water and the boron trifluoride on the solid adsorbent and that these cumulative effects help to cause the inverse relationship of temperature with conversion.
• reaction temperature therefore refers to the highest temperature or "hot spot" temperature in the catalyst bed.
• a uniform temperature will be present in a slurry reactor.
• the boron trifluoride gas and the 1-olefin are either jointly introduced into the inlet end
• the boron trifluoride can be injected into the 1-olefin feed stream immediately prior to its introduction into the reactor.
• This procedure is followed i ⁇ essentially eliminate any direct reaction in the olefin feed line of the boron trifluoride with the water dissolved in the olefin and/or avoid undesired and uncontrolled oligomerization in the olefin feed line prior to the reactor itself.
• this procedure permits the boron trifluoride and the water to be adsorbed by the solid particulate material within the reactor to form the three-component catalyst system in the desired manner.
• boron trifluoride continuously desorbs from the solid adsorbent during the course of the reaction, it is necessary to feed boron trifluoride to the reaction inlet to insure that sufficient boron trifluoride is present in the catalyst for the oligomerization reaction.
• the adsorption and desorption of the boron trifluoride is ' affected by many operating variables including temperature, pressure, moisture content, nature and particle size of the solid adsorbent, the composition of the feed and the reaction mixture, and the like.
• the minimum feed rate of the boron trifluoride will therefore depend on the par ⁇ ticular operating conditions in any .specific situation.
• the boron trifluoride feed rate is at least equal to its solubility in the reaction liquid at the particular conditions of operation, and preferably is in excess of its solubility in the reaction liquid.
• the solubility of the boron trifluoride in the reaction liquid is significantly affected by the partial pressure of boron trifluoride in the gas phase.
• Pure boron trifluoride gas can be utilized or it can be used in admixture with an inert gas such as nitrogen, argon, helium, and the like. When used as a mixture, it is preferred that it.comprise. at least about 10 mol percent of the gas mixture. Because of the many variables involved, as indicated, it is difficult to specify a feed rate for the boron trifluoride for any particular set of operating variables, although it can be stated that, in general, it will be at least about 0.1 weight percent of the 1-olefin. It is more meaningful to indirectly indicate the amount of boron trifluoride fed to the reactor by specifying the partial pressure of boron trifluoride in the reactor.
• oligomerization reaction can be carried out at atmospheric pressure when using pure boron tri- fluoride, we find it desirable to maintain a partial pressure of boron trifluoride in the reactor of at least about 10 psig. (0.17 MPa) for suitable catalyst activity and preferably at least about 50 psig. (0.44 MPa) for superior catalyst activity. Partial pressures of boron • trifluoride as high as about .500 psig. (3.55 MPa) and higher, such as about 1,000 psig. (7.03 MPa), can be utilized but it is preferred that an operating partial pressure of about 250 psig. (1.83 MPa) not be exceeded.
• the elevated pressures are, in general, avoided where their possible benefits in improved catalyst activity are outweighed by the added boron trifluoride and process costs. Lower operating pressures also appear to result in an improved product quality, possibly resulting from reduced isomerization.
• suitable results can be obtained with a relatively high throughput of the liquid reactant olefin. In fact, we find that conversion of the 1-olefin is only moderately decreased as the space velocity of the reactant liquid is increased. In the case of a 1-decene feed an increase in space velocity results in an increase in the dimer and a corresponding decrease in the higher oligomer fractions.
• the oligomerization reaction in a fixed bed can
• OMPI conveniently be carried out within the broad range of liquid hourly space velocities, that is, the volume of the liquid feed per.volume of catalyst per hour, of between about 0.1 and about 50 hr.” 1 , but preferably the reaction is carried out within the range of about 0.5 and about 10 hr. ⁇ . These ranges for space velocity are also applicable with a flow-through slurried catalyst system.
• the particular reaction conditions utilized will depend on the 1-olefin feed that is used and the product oligomer, fraction or fractions, that is desired. Although it is preferred that the reaction be carried out at maximum conversion and optimum selectivity to desired products, such may not be possible. However, the overall selectivity may be substantially improved if those oligomer fractions lower than the desired oligomer fractions are recovered from the product stream and recycled to the feed stream for further reaction. Since the oligomer fractions which are heavier than the desired fractions represent a process loss, it may be desirable to operate the oligomerization reaction under conditions which minimize the undesired heavier fractions even though this may increase the amount of product recycle.
• reaction liquid refers to the alpha-olefin monomer or mixture of monomers, any inert solvent, if present, and the oligomer products which will be present once reaction has started. It is possible to carry out the reaction in the presence of up to about 80 percent, preferably up to about 60 percent, of a suitable inert solvent. Suitable solvents can be used for temperature control and for product control.
• Suitable solvents can be selected from aliphatic hydrocarbons such as pentane, hexane, heptane, and the like;- and aromatic hydrocarbons, such as benzene, toluene, chlorobenzene, and the like.
• the solvent if utilized, should be liquid at reaction conditions and should be substantially lower in boiling point than any other component to simplify separation upon completion of the reaction.
• the three- component catalyst is maintained as a slurry in the reac ⁇ tion liquid by suitable agitation.
• a suitable porous plate is positioned between the reaction liquid and the reactor outlet.
• a continuous stream of reaction product is removed at a rate to provide a predetermined desirable average residence time in the reactor. Since the filter plate prevents the egress of the powdered adsorbent, the product stream is free of solids.
• make-up alpha-olefin is injected into the reactor inlet to provide a constant liquid volume in the reactor.
• the particle size of the adsorbent, the openings in the filter plate and the vigor of the agitation are appropriately intercorrelated to insure that the adsorbent particles neither block the filter openings nor cake up on the filter plate.
• the batch method can be carried out in the same equipment with the catalyst remaining in the reactor between batches or if a filter plate is not used, the slurry can be removed from the reactor at the termination of a batch, filtered and the catalyst returned for the next batch.
• the reaction product which is removed from the reactor contains unreacted feed olefin, the various product oligomer fractions, any impurities which were originally present in the feed olefin, inert solvent when used, and dissolved boron trifluoride gas.
• the amount of boron trifluoride in the product liquid will. in general, fall within the range of between about 0.1 and about 20 weight percent depending upon the amount of boron trifluoride that is fed to the reactor and usually in the lower end of this range.
• This boron trifluoride can be readily separated from the liquid product in nearly quantitative yield by subjecting the " product solution to. a vacuum at about 100° C, by heating the product liquid to 100° C. and bubbling nitrogen through the liquid, or by any other appropriate procedure.
• This separated boron trifluoride is reusable in the process without any change in the activity of the three-component catalyst system. Traces of the boron trifluoride can be removed from the reaction product with a water wash. The liquid reaction product can then be hydrogenated to eliminate double bond unsaturation either before or after its separation into the desired fractions.
• 1-decene feed line immediately before it entered into the reactor.
• the product stream was collected in a 500 cc. receiver.
• the 1-decene typically contained 1.5 percent saturates and other olefins.
• the solid adsorbent was Davison Grade 59 silica having a B.E.T. area of about 250 m 2 /g, which was calcined at 1,000° F. (538° C.) and sized to the desired mesh size.
• the reactor was packed with 60 cc. of the silica and boron trifluoride gas was injected into the reactor and maintained under pressure for 30 minutes before each series of experiments. Product analysis was carried out with a liquid or gas chromatograph as appropriate. The flow rate of the boron trifluoride gas in the following examples has been standardized to one atmosphere pressure and a temperature of 60° F. (15.6° C.) .
• the reactor contained 60 cc. of 40/50 mesh (0.3 to 0.42 mm.) silica.
• the reactor was operated at an outlet pressure of 250 psig. (1.83 MPa). After operating for three hours to insure stable operation, analyses of the reaction products were begun. The temperature in the catalyst bed began to rise moderately in the 49th hour, which was believed to be the cause of a shift in the product selectivity. The results are set out in Table I.
• Example 2 The experiment of the preceding example was continued in all details except that the feed of boron trifluoride was cut in half to 5.70 cc. per minute. However, after about four hours, the dry 1-decene was replaced with 1-decene which contained 28 ppm. water (the average of two analyzed samples) . After conditions in the reactor stabilized, the conversion increased to its original value and stayed there for about 20 additional hours as set out in Table II.
• the reactor contained 60 cc. of a fresh batch of 40/50 mesh (0.3 to 0.42 mm.) silica which had been pretreated with boron trifluoride under pressure.
• the 1-decene contained 42 ppm. water and was fed to the reactor at a rate of 300 cc. per hour which is a liquid hourly space velocity of 5.0 hr"" 1 .
• Boron trifluoride gas was fed to the 1-decene* immediately prior to the reactor at a rate of 38.8 cc. per minute, which was 3.14 weight percent boron trifluoride based on the 1-decene.
• the reactor outlet was operated at 150 psig. (1.14 MPa).
• the hot spot temperature in the reactor rose for the first several hours dropping after about eight hours to steady state operation.
• the results of 43 hours of operation are set out in Table III.
• Example 4 A series of experiments were conducted to determine the effect of reactor pressure on catalyst activity as determined by the-conversion of 1-decene and on product selectivity.
• a fresh 30 cc. batch of the 40/50 mesh silica was placed in the reactor and was treated with boron trifluoride gas at 240 psig. (1.76 MPa) for 30 minutes.
• the results are set out in Table IV in which the pressure is the outlet pressure and the temperature is the hot spot temperature in the catalyst bed. Table IV
• Example 5 The effect of variations in the moisture con- tent of the feed 1-decene was studied in a series of experiments.
• the catalyst used in Example 5 was also used in these experiments and all other reaction condi ⁇ tions were the same except as shown in Table VI which sets out the results of these experiments.
• Example 8 This example demonstrated the high activity of a catalyst after 257 hours of reaction time.
• the catalyst was used over a large number of experiments at many > different reaction conditions including a cycle of experiments using pure 1-decene feed followed by a cycle of experiments using a feed stream comprising 1-decene with a dimer fraction.
• the amount of water in the feed varied from a low of 12 ppm. to a high of 80 ppm. over the series of experiments.
• the solid adsorbent was 30 cc. of a 20/30 mesh (0.59 to 0.84 mm.) silica.
• the reactor was operated at an outlet pressure of 125 psig. (0.965 MPa). After seven hours of this experiment, which was a total of 148 hours use of the catalyst, at which time the hot spot temperature was 27° C. , analysis of the product showed a conversion of 82.4 percent at a selectivity of 31.6 percent to the dimer, 60.1 percent to the trimer and 7.3 percent to the tetramer.
• OMPI - the monomer-dimer product was added to the pure 1-decene to provide a feed stream containing 17 percent dimer.
• this feed stream which also contained 32 ppm. water was introduced into the reactor at a rate of 30 cc. per hour and the boron trifluoride was fed at the rate of 12.0 cc. per minute. " The reactor was operated, at an outlet pressure of 125 psig. (0.965 MPa).
• Example 9 In a further series of runs a 30 cc. sample of a 10/20 mesh (0.84 to 2.0 mm.) silica was used as the solid adsorbent.
• 70 cc. of a feed comprising 1-decene a sufficient amount of the monomer- dimer fraction described in Example 8 to provide 15 percent dimer and 26 ppm. water was introduced into the reactor at a rate of 70 cc. per hour.
• the boron trifluoride was fed at a rate of 3.10 cc. per minute, which was one percent boron trifluoride in the feed mixture.
• the hot spot temperature was 11° C. and the outlet pressure was 100 psig. (0.793 MPa). Analysis of the product after four hours at these operating conditions showed a conversion of 85.4 percent at a selectivity of 23.3 percent to dimer, 61.4 percent to trimer and 14.7 percent to tetramer.
• Example 10 Example 9 was repeated at the same conditions except that the 1-olefin feed rate was 73 cc. per hour and the water content of the feed was 37 ppm.
• the signifi ⁇ cant difference was a reduction in the feed rate of the boron trifluoride down to a rate of 1.50 cc. per minute, which was 0.49 percent of the 1-olefin mixture fed to the reactor.
• analysis of the product showed a drop in the conversion down to 67.6 percent at a selectivity of 18.7 percent to the dimer, 67.1 percent to the trimer and 11.7 to the tetramer. Further analysis after operating an additional hour showed that the conversion had further dropped to 50.5 percent without much change in the selectivity.

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• 1981
  • 1981-05-22 JP JP50243881A patent/JPS58500758A/ja active Pending
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