US3849297A - Process for removing metals from petroleum residua - Google Patents

Abstract

A process is provided for removing metal contaminants such as vanadium, nickel and iron, particularly vanadium and nickel, from hydrocarbon fractions. The process comprises contacting the hydrocarbon with an extractant comprising molten sulfur and a Group VB metal salt.

Description

United States Patent [1 91 Long [ Nov. 19, 1974 PROCESS FOR REMOVING METALS FROM PETROLEUM RESIDUA [75] Inventor: Robert Byron Long, Atlantic Highlands, NJ.

[7 3] Assignee: Exxon Research and Engineering Company, Linden, NJ.

22 Filed: June 8,1972

21 Appl. No.: 260,757 I [52] US. Cl. 208/251 R, 208/253 [51] Int. Cl Cl0g 17/00 [58] Field of Search 208/253, 251 I [56] References Cited UNITED STATES PATENTS 9/1958 Weller et al, 208/251 H 3,180,820 4/1965 Gleim et al. 208/251 H 3,622,495 l/1970 Gatsis 208/251 H 3,622,498 11/1970 Stolfa 208/251 H Primary Examiner-Delbert E. Gantz Assistant Examiner-Juanita M. Nelson Attorney, Agent, or Firm-Jay Simon [5 7 ABSTRACT 20 Claims, No Drawings PROCESS FOR REMOVING METALS FROM PETROLEUM RESIDUA The present invention relates to the removal of metal contaminants from hydrocarbon fractions. More particularly, the present invention relates to a process for removing heavy metals such as vanadium, nickel or iron, particularly vanadium and nickel, from petroleum fractions such as crude oil or residual fractions.

Many hydrocarbon feedstocks contain appreciable amounts of heavy metals such as vanadium, nickel and iron or compounds thereof. These metallic contaminants may exist within the hydrocarbonaceous material in a variety of forms, generally being present as complexed organometallic compounds of relatively high molecular weight, for example as metal porphyrins and various derivatives thereof. These heavy metals or metal compounds can deteriorate the activity of and poison certain types of catalysts, when present in feedstocks subjected to catalytic treatment. Cracking catalysts, such as silica-alumina catalysts, alone or in admixture with other metal oxides suitable for cracking, are particularly susceptible to deterioration and poisoning by heavy metals such as vanadium, iron and nickel and the like.

The problems surrounding the presence of these heavy metal contaminants have long troubled those working in the art; however, efforts heretofore made to reduce the levels of such contaminants have not been entirely satisfactory. U.S. Pat. No. 2,854,399 states that petroleum fractions derived from crude oils, and containing heavy metal components deleterious to the cracking of such oils, can be catalytically cracked after contacting such fractions with sulfur and removing any resulting heavy metal sulfides and excess elemental sulfur. While this method does aid in reducing the levels of heavy metal contaminants, certain of the contamimants, especially vanadium, remain in sufficient amounts to rapidly poison the cracking catalysts. U.S. Pat. No. 3,474,029 relates to a process for hydrorefining a metal contaminated, asphaltene-containing hydrocarbon charge stock. According to this patent, the

. charge stock is contacted with a catalyst and hydrogen I in the presence of a thioester of a metal selected from the group consisting of metals of Group VB and Group VlB to maintain the activity of the catalyst. U.S. Pat.

9 No. 3,619,410 states that metallic contaminants can be removed during the conversion of hydrocarbonaceous black oils with hydrogen and hydrogen sulfide by the addition of an aqueous solution of the double salt vanadyl sulfite-ammonium sulfite. The approaches suggested by the latter two patents require the use of costly materials and are restricted to highly inflexible processing schemes.

It is an object of the present invention to provide a highly flexible and efficient method for removing metal contaminants such as vanadium, nickel and iron from hydrocarbon fractions.

This and other objects are accomplished by the presentinvention which provides a process for reducing the level of metal contaminants in a hydrocarbon material which comprises contacting the hydrocarbon with an extractant comprising elemental sulfur and a Group VB metal salt, and thereafter separating at least a portion of the extractant and metal contaminants from said hydrocarbon material.

While any hydrocarbon feedstock containing metal contaminants can be treated according to the process of the present invention, this process is particularly suitable for removing metal contaminants from petroleum materials such as crude oil or residual fractions,

' especially from long residua (a major portion of the fraction boils in excess of 460F at atmospheric pressure) and short residua (a major portion of the fraction boils in excess of l,000F at atmospheric pressure). The hydrocarbon materials may typicially contain from about 100 to 3,000 wppm vanadium, 10 to 1,500 wppm ides, and selenides of vanadium, niobium and tantalum.

Vanadium sulfides, especially vanadium sesquesulfide (V 8 and vanadium pentasulfide (V 8 or mixtures thereof, are particularly preferred. The Group VB metal salt can be-either supported or unsupported. When unsupported it can be added before or after admixture of the hydrocarbon with the sulfur. When supported, the Group VB metal salt is typically dispersed on a support material such as silica, alumina, silicaalumina, titania, zirconia, thoria, and the like, and the hydrocarbon and molten sulfur are mixed and passed thereover. Whether the Group VB metal salt is supported or unsupported, the sulfur is used in an amount of from about 0.001 to 10 wt. percent based on the weight of the hydrocarbon, preferably 0.5 to 5.0 wt. percent, and most preferably 0.9 to 1.5 wt. percent. The Group VB metal salt functions as a promoter, and, whether supported or unsupported, it must be used in an effective promoting amount. When unsupported, the Group VB metal salt is preferably present in amounts ranging from 0.l to 10 wt. percent, most preferably 0.5 to 2.0 wt. percent, based on the weight of the hydrocarbon feed. When supported, the hydrocarbon/- sulfur mixture is passed over the supported Group VB metal salt at a space velocity within the range of from about 0.01 to 100, preferably 1 to 5, volumes of oil and sulfur per volume of supported Group VB metal salt per hour (v/v/hr.).

The treatment temperature employed according to the present invention must be sufficiently high in order to provide liquid phase contact; however, the treatment temperature should be below about 400C. Above this temperature substantial reaction of the sulfur with the hydrocarbon is experienced and undesirable sulfur compounds are produced. Typically, the treatment temperature ranges from about to 350C, and preferably from about 200 to 300C. The reaction zone pressure is not critical. The contacting period may range from about 0.1 to 10 hours, preferably from about 0.2 to 2 hours.

The sulfur/Group VB metal salt extractant and the hydrocarbon feed are preferably contacted in amixing zone provided with a mixing apparatus capable of causing intimate contact between the phases. Centrifugal pumps, mixing orifices. paddle wheels, and other high shear devices, or combinations thereof, are suitable means for assuring intimate contact between the sulfur/Group VB metal salt extractant and the hydrocarbon being treated.

Following Contact of the hydrocarbon with the sul- The following examples are presented for the purpose of more clearly illustrating the present invention and are not to be taken as limiting the invention to the particular reactants or conditions employed.

fur/Group VB metal salt extractant, the extractant con- 5 taining the metal contaminants (i.e., contaminant metals that are complexed and/or compounded with the EXAMPLES l9 ig the Group Salts g q g unreactefl In each of the following examples, the designated Ur) g removed E i mater" amount of 460F+ residual cut from Venezuelan crude 5 may 6 remove Jmme late y Y t e contact' 10 was contacted with the specified extractant in a pyrex mg step or after Subsequent Processing steps where tube that was positioned within an oil bath maintained P sqbsequem steps not result adversfi reac' at the indicated temperature. This residua contained tlons with, or be retarded by, the presence of these ma- 290 Wppm Vanadium 37 wppm nickel, 223 wt percent 'f i Theise mfuenals r pmferably removed from sulfur, and exhibited a gravity of 16.9 API and 21 Conthe oil by dlssolvmg the oil therefrom w1th a hydrocarl radson Carbon number of percent In each cxam bon solveom at a temperature w'thm the ra nge of from ple, the extractant and the residua were continuously about to 100 F and r a Pressure wrthm o range agitated by bubbling nitrogen through the tube. After of r about armospherro Pr o 500 psrg' The allowing the residua and extractant to react for one partrcuraraolverrt ernployed not crmcal but can be hour at atmospheric pressure, the tube was removed y effectrye materral from P P o p to a refinery 20 from the bath and the contents cooled. Thereafter, the naphtha Stream Preferred Solvents include paraffitllc treated 011 was contacted and stirred with 200 millili hydrocarbons or mrXturoS thereof, wrth heptane bemg ters of normal heptane at room temperature for about Particularly Preferrodyp yr 2 t0 P 1 hour. The total mixture was then centrifuged to rey 3 to 5, Volumes of Solvent are p y P Volume move the solids. The resulting solids were thereafter of 25 washed with additional heptane to remove residual oil Alternatively, separatlon can be acoompllshed y and then dried in air at room temperature. Both the re- P y P g the oil/Sulfur mlXturo to Stand for a covered oil and the solid materials were analyzed using period of time sufficient for the unreacted sulfur, the emission spectroscopy techniques. The vanadium Group VB meta Salt, an the eac ed a CO sesquesulfide (V 8 used in these examples was preplexed contaminant metals, to settle out from the hypared by treating vanadium pentoxide (V 0 with h drocarbon material. Substantially complete separation drogen sulfide (H 5); about 50 percent of unreacted by settling will occur within about 8 hours. The settling vanadium pentoxide still remained in the samples used. period can be markedly reduced by centrifuging the Unless otherwise stated, all parts and percentages are total mixture. by weight. Table 1 summarizes the results obtained.

TABLE I Example l Example 2 Example 3 Example 4 (control) (comparative) Extractant V 8 (1%) V 8 (1%) S (1%) (wt.% on feed) None S(l%) S(l0%) Temperature, C 25 200 X00 150 200 I00 200 I00 l 200 Treated Oil v, ppm 140 110 125 30 110 26 100 79 Ni. m 20 12 5 5 5 22 3 13 10 10 s. wt.% 2.23 1.9 2.7 3.1 1.8 10.2 6.7 3.1 6.0 2.0 Solids v. ppm 2050 2225 5000 5000 5000 2.3%) (1.4%) 2250 1800 2000 N1. pp 270 265 275 240 195 216 122 260 190 235 5, WI.% 3.62 4.21 3.19 3.76 3.44 15.3 9.5 3.79 36.0 4.23 Solids. wt.% on-fced 8.1 8.4 11.0 10.4 16.1 10.4 22.8 8.3 13.5 10.11

Example 5 Example 6 Example 7 (comparative) (comparative) (comparative) Extractant Na s (l%) Na s (5%) V20, l /r) V20, (5%) (wt.% onfced) s 10% s(1%) s(5% s(1%) s(5% Temperature, C 200 200 200 200 200 Treated on v. ppm 87 47 100 95 70 43 Ni. ppm 11 6 11 11 9 4 s, 911.96 7.4 6.3 1.1 1.9 1.7 2.0 Solids v. m 1625 1375 1825 1925 (0.99% 2.1%) Ni. m 190 238 213 285 224 5. wt.% 25.6 15.9 2.86 5.02 4.57 6.87 sd1ids.wu1t on feed 10.5 15.8 9.0 10.0 12.7 27.0

TABLE I Continued Example 8 Example 9 (comparative) (comparative) Extractant V25; (2%) (wt.% on feed) S (2%) 7 Temperature, C 200 200 Treated Oil V, ppm 63 88 Ni, ppm 7 l l 5, wt.% [.8 1.6 Solids V. ppm Not Available Not Available Ni, ppm Not Available Not Available S, wt.% Not Available Not Available Solids, wt.% on feed Not Determined Not Determined J l5 Example 1 1s a control experiment and indicates the from 0.1 to wt. percent based on the weight of the degree of metals removal which can be achieved achydrocarbon. cording to the processing scheme employed without 6. A process according to claim 1 wherein the prothe addition of an extractant. Examples 2 and 3 illusmoter is dispersed on a support material and the hydrotrate the highly efficient metals removal which can be carbon is contacted with the extractant by admixing the achieved by using the extractant according to the presy a n and e e emental Sulfur and passing the ent invention. As noted above, the vanadium sulfide l'fisllltaht miXtUfe Over the pported Group B metal used was, in fact, a mixture of V 8 and V 0 as added Salt at a Space velocity from 001 to 100 /h to the reaction zone. A comparison of Examples 2 and P flccordlng t0 Glam 6 Wherem the Space 3 with Example 7 shows, however, that a substantial veloclty 15 with! the "h of 1 t 5 difference in performance is secured when one starts A Process aeeordmg to ela'm 1 Wherem the e with a mixture containing at least some vanadium sultraetaht Separated from the hydrocarbon by allowmg fide as opposed to starting with vanadium pentoxide. the extraetaht to semehom the .hydreearheh- Additionally, a comparison of the results of Examples A phoeess aceordmg to Clam 1 wherem the e 2 and 3 to the results of Examples 4 and 5 indicates a traePaht separated m the hydfoearbeh by clear Superiority of the use of the extractam of the pres solving the oil therefrom with a paraffmic hydrocarbon. ent invention as opposed to the use of sulfur alone. 0 And, comparative Example 6 illustrates that other ma- 1 A prochss accordlgg to 12} 1 wherelh e proterials such as sodium sulfide do not function in the i f a "*3? 1 h h 7 same manner as the vanadium material. accor. mg to i. am i h Comparison of Examples 2, 8 and 9 shows a definite motegcompriges a mlxture 0 a Vana mm l e synergism in the use of mixtures of V 5 with sulfur i 2 t l 10 h th rather than the use of either component alone. .process.accor mg 0 c.alm w .erem e pmmoter lS vanadium sesquesulfrde, vanadium pentasul- What is claimed 18. 40

fide or a mixture thereof. 1. A process for reducing the level of metal contaml- 13. A process for reducing the level of metal contamnants m a hydrocarbon material selected from the mants m a hydrocarbon material selected from the group consisting of crude oil or a residual petroleum f d I I fraction which comprises contacting the hydrocarbon group Consisting- 0 cm e a reel petro cum l t t b 400C fraction containing the same which comprises contactmatena at a f g g i 3 w] b ing the hydrocarbon material at a temperature varying g h g g g s percenlt 1 3 from 150 to 350C. with an extractantcomprising 0.05 t e to e f g 0 e emenia an to 5.0 wt. percent, based on the weight of the hydrocara Promoter Se ecte mm 6 group. Conslstmg o bon, of elemental sulfur and from 0.1 to 10 wt. percent, ported and unsupported oxides, sulfides, and selemdes based on the weight of the hydrocarbon, of an unsuph of h tantalum m'xthres thereof ported sulfide of vanadium and thereafter separating at and themse where the Promoter unsupported the least a portion of the extractant and metal contamipromoter is present in an amount of from 0.] to 10 wt. ants f Said hydrocarbon Percent, based h the Welght of e hydrocarbon, and 14. A process of claim 13 wherein said extractant thereafter separating at leastaportron of the extractant comprises from 0.9 to 15 wt percent, based on the h meta] cohtammams from l hydrocarbon mate weight of the hydrocarbon, of elemental sulfur and 0.5 Hal. to 2.0 wt. percent of an unsupported sulfide of vana- 2. A process according to claim 1 wherein the hydrodi carbon iS COl'ltfiCtfid with the extractant at a tempera- 15, The process of claim 13 wherein the extractant ture of from about 150 to 350C- is separated from the hydrocarbon material by dis- A Pmcess accol'dlng to Clalm 1 wherein the Sulfur solving the hydrocarbon material with a paraffinic hyis present in an amount of 0.5 to 5.0 wt. percent based drocarbon on the weight of the hydrocarbon. 16. The process of claim 14 wherein the extractant 4. A process according to claim 3 wherein the sulfur is separated from the hydrocarbon material by disis present in an amount of from 0.9 to 1.5 Wtp rcen solving the hydrocarbon material with a paraffinic hybased on the weight of the hydrocarbon.

5. A process according to claim 1 wherein the prorngter isunsupported and is present in an amount of drocarbon.

17. A process for reducing the level of metal contaminants in a hydrocarbon material selected from the group consisting of crude oil or a residual petroleum fraction which comprises contacting the hydrocarbon material at a temperature below 400C. with an extractant comprising 0.001 to 10 wt. percent, based on the weight of the hydrocarbon, of elemental sulfur and an effective promoting amount of a promoter selected from the group consisting of the oxides, sulfides, and selenides of vanadium, tantalum, niobium or mixtures thereof, and thereafter separating at least a portion of the extractant and metal contaminants from said hydrocarbon material, the promoter being present in an based on the weight of the hydrocarbon.

V i =l

Claims (20)

1. A PROCESS FOR REDUCING THE LEVEL OF METAL CONTAMINANTS IN A HYDROCARBON MATERIAL SELECTED FROM THE GROUP CONSISTING OF CRUDE OIL OR A RESIDUAL PETROLEUM FRACTION WHICH COMPRISES CONTACTING THE HYDROCARBON MATERIAL AT A TEMPERATURE BELOW 400*C. WITH AN EXTRACTANT COMPRISING 0.001 TO 10WT. PERCENT, BASED ON THE WEIGHT OF THE HYDROCARBON, OF ELEMENTAL SULFUR AND A PROMOTER SELECTED FROM THE GROUP CONSISTING OF SUPPORTED AND UNSUPPORTED OXIDES, SULFIDES, AND SELENIDES OF VANADIUM, TANTALUM, NIOBIUM OR MIXTURES THEREOF, AND IN THE CASE WHERE THE PROMOTE IS UNSUPPORTED THE PROMOTER IS PRESENT IN AN AMOUNT OF FROM 0.1 TO 10WT. PERCENT, BASED ON THE WEIGHT OF THE HYDROCARBON, AND THEREAFTER SEPARATING AT LEAST A PORTION OF THE ETRACTANT AND METAL CONTAMINANTS FROM SAID HYDROCARBON MATERIAL.

2. A process accOrding to claim 1 wherein the hydrocarbon is contacted with the extractant at a temperature of from about 150* to 350*C.

3. A process according to claim 1 wherein the sulfur is present in an amount of 0.5 to 5.0 wt. percent based on the weight of the hydrocarbon.

4. A process according to claim 3 wherein the sulfur is present in an amount of from 0.9 to 1.5 wt. percent based on the weight of the hydrocarbon.

5. A process according to claim 1 wherein the promoter is unsupported and is present in an amount of from 0.1 to 10 wt. percent based on the weight of the hydrocarbon.

6. A process according to claim 1 wherein the promoter is dispersed on a support material and the hydrocarbon is contacted with the extractant by admixing the hydrocarbon and the elemental sulfur and passing the resultant mixture over the supported Group VB metal salt at a space velocity of from 0.01 to 100 v/v/hr.

7. A process according to claim 6 wherein the space velocity is within the range of 1 to 5 v/v/hr.

8. A process according to claim 1 wherein the extractant is separated from the hydrocarbon by allowing the extractant to settle from the hydrocarbon.

9. A process according to claim 1 wherein the extractant is separated from the hydrocarbon by dissolving the oil therefrom with a paraffinic hydrocarbon.

10. A process according to claim 1 wherein the promoter comprises a vanadium sulfide.

11. A process according to claim 10 wherein the promoter comprises a mixture of a vanadium sulfide and vanadium oxide.

12. A process according to claim 10 wherein the promoter is vanadium sesquesulfide, vanadium pentasulfide or a mixture thereof.

13. A process for reducing the level of metal contaminants in a hydrocarbon material selected from the group consisting of crude oil or a residual petroleum fraction containing the same which comprises contacting the hydrocarbon material at a temperature varying from 150* to 350*C. with an extractant comprising 0.05 to 5.0 wt. percent, based on the weight of the hydrocarbon, of elemental sulfur and from 0.1 to 10 wt. percent, based on the weight of the hydrocarbon, of an unsupported sulfide of vanadium and thereafter separating at least a portion of the extractant and metal contaminants from said hydrocarbon.

14. A process of claim 13 wherein said extractant comprises from 0.9 to 1.5 wt. percent, based on the weight of the hydrocarbon, of elemental sulfur and 0.5 to 2.0 wt. percent of an unsupported sulfide of vanadium.

15. The process of claim 13 wherein the extractant is separated from the hydrocarbon material by dissolving the hydrocarbon material with a paraffinic hydrocarbon.

16. The process of claim 14 wherein the extractant is separated from the hydrocarbon material by dissolving the hydrocarbon material with a paraffinic hydrocarbon.

17. A process for reducing the level of metal contaminants in a hydrocarbon material selected from the group consisting of crude oil or a residual petroleum fraction which comprises contacting the hydrocarbon material at a temperature below 400*C. with an extractant comprising 0.001 to 10 wt. percent, based on the weight of the hydrocarbon, of elemental sulfur and an effective promoting amount of a promoter selected from the group consisting of the oxides, sulfides, and selenides of vanadium, tantalum, niobium or mixtures thereof, and thereafter separating at least a portion of the extractant and metal contaminants from said hydrocarbon material, the promoter being present in an amount of from about 0.1 to 10 wt. percent, based on the weight of the hydrocarbon.

18. The process of claim 17 wherein the promoter is selected from the group consisting of vanadium sulfide, vanadium sesquesulfide, vanadium pentasulfide and mixtures thereof.

19. The process of claim 18 wherein the temperature ranges frOm about 150* to 350*C.

20. The process of claim 19 wherein the sulfur is present in an amount of from 0.5 to 5.0 wt. percent, based on the weight of the hydrocarbon.