US007862708B2 (12) United States Patent (10) Patent No.: US 7,862,708 B2 Siskin et al. (45) Date of Patent: Jan. 4, 2011 (54) PROCESS FOR THE DESULFURIZATION OF 2005/0133405 A1 6/2005 Wellington et al. HEAVY OLS AND BITUMENS 2005/0145536 A1 7/2005 Wellington et al. 2005/O155906 A1 7/2005 Wellington et al. (75) Inventors: Michael Siskin, Westfield, NJ (US); 2007/0102323 A1 5/2007 Lee et al. Rustom M. Billimoria, Hellertown, PA FOREIGN PATENT DOCUMENTS (US); David W. Savage, Zionsville, IN (US); Roby Bearden, Jr., Baton Rouge, BE 888.421 10, 1981 LA (US) WO WO99/15605 4f1999 WO WO 2005/061665 A2 7/2005 Assignee: ExxonMobil Research and WO WO 2005/061670 A2 7/2005 (73) WO WO 2005/061671 A2 7/2005 Engineering Company, Annandale, NJ WO WO 2005/063936 A2 7/2005 (US) WO WO 2005/066304 A2 7/2005 WO WO 2005/066305 A2 7/2005 (*) Notice: Subject to any disclaimer, the term of this WO WO 2005/066309 A2 7/2005 patent is extended or adjusted under 35 U.S.C. 154(b) by 113 days. OTHER PUBLICATIONS Claudio Bianchini, Andrea Meli; “Hydrogenation, hydrogenolysis, (21) Appl. No.: 12/287,744 and hydrodesulfurization of thiophenes.” Multiphase Homogeneous Catalysis (2005), vol. 1, 196-202. Abstract. (22) Filed: Oct. 14, 2008 Atsushi Kishita, Satoru Takahashi, Hirotaka Kamimura, Masami Miki, Takehiko Morita, Heiji Enomoto; “Upgrading of Bitumen by (65) Prior Publication Data Hydrothermal Visbreaking in Supercritical Water with Alkali.” Regu US 2009/O152168A1 Jun. 18, 2009 lar Paper, Graduate School of Environmental Studies, Tohoku Uni versity, Sendai, Japan. Atsushi Kishita, Satoru Takahashi, Hirotaka Kamimura, Masami Related U.S. Application Data Miki, Takehiko Moriya, Heiji Enomoto, “Hydrothermal Visbreaking (60) Provisional application No. 61/007,593, filed on Dec. of Bitumen in Supercritical Water with Alkali.” Regular Paper, Dept. 13, 2007. of Geoscence and Technology, Graduate School of Engineering, Tohoku University, Sendai, Japan. (51) Int. C. Atsushi Kishita, Satoru Takahashi, Yuki Yamasaki, Fangmin Jin, Takehiko Moriya, Heiji Enomoto; “Desulfurization of Bitumen by CIOG 45/04 (2006.01) Hydrothermal Upgrading Process in Supercritical Water with (52) U.S. Cl. ....................... 208/229; 208/213; 208/230; Alkali.” Regular Paper, Graduate School of Environmental Studies, 208/235; 208/250; 208/208 M Tohoku University, Sendai, Japan. (58) Field of Classification Search ................. 208/177, Atsushi Kishita, Satoru Takahashi, Fangmin Jin, Yuki Yamasaki, 208/208 R, 209, 213, 226, 229, 230, 235, Takehiko Moriya, Heiji Enomoto; "Decomposition of 208/250, 208 M Benzothiophene, Dibenzothiophene, and Their Derivatives in See application file for complete search history. Subcritical and Supercritical Water with Alkali.” Regular Paper, Granduate School of Environmental Studies, Tohoku University, (56) References Cited Sendai, Japan. U.S. PATENT DOCUMENTS * cited by examiner 2.379,654 A 7/1945 Royer Primary Examiner Glenn Caldarola 2,864,761 A 12/1958 D’Ouville et al. Assistant Examiner—Randy Boyer 3,401, 101 A 9, 1968 Keller, Jr. ................... 205,696 (74) Attorney, Agent, or Firm—Bruce M. Bordelon 3,948,754 A 4, 1976 McCollum et al. 3,960,708 A 6, 1976 McCollum et al. ... 208/121 (57) ABSTRACT 4,003,823. A * 1/1977 Baird, Jr. et al. ............ 208/108 4,005,005 A 1/1977 McCollum et al. 4,127,470 A * 1 1/1978 Baird et al. ................... 208,58 The present invention relates to a process for desulfurizing 4,248.693. A 2f1981 Swanson bitumen and other heavy oils such as low API gravity, high 4,437,980 A * 3/1984 Heredy et al. ............... 208,235 Viscosity crudes, tar sands bitumen, or shale oils with alkali 4,468.316 A 8, 1984 Swanson metal compounds under conditions to promote in-situ regen 4473.462 A 9, 1984 Swanson eration of the alkali metal compounds. The present invention 4,564,439 A 1, 1986 Kuehler et al. ................ 208.59 employs the use of Superheated water and hydrogen under 5,338.442 A 8, 1994 Siskin et al. 5,611,915 A 3, 1997 Siskin et al. conditions to improve the desulfurization and alkali metal 5,935,421 A * 8/1999 Brons et al. ................. 208,226 hydroxide regeneration kinetics at Sub-critical temperatures. 6,294,093 B1 9/2001 Selvarajan et al. 6,887,369 B2 * 5/2005 Moulton et al. ............. 208/107 9 Claims, 3 Drawing Sheets U.S. Patent Jan. 4, 2011 Sheet 1 of 3 US 7,862,708 B2 60 65 FIGURE 1 U.S. Patent Jan. 4, 2011 Sheet 2 of 3 US 7,862,708 B2 20 45 15 35 40 5 10 30 55 60 50 65 <- 105 (8100 115 110 125 FIGURE 2 U.S. Patent Jan. 4, 2011 Sheet 3 of 3 US 7,862,708 B2 225 FIGURE 3 US 7,862,708 B2 1. 2 PROCESS FOR THE DESULFURIZATION OF tions for use in processes such petroleum refining processes. HEAVY OLS AND BITUMENS If a significant amount of the sulfur is not removed from these feedstocks prior to refining, significant costs in capital equip This Application claims the benefit of U.S. Provisional ment may be required to process these corrosive crudes and Application No. 61/007,593 filed Dec. 13, 2007. the sulfur is generally still required to be removed by subse quent processes in order to meet intermediate and final prod FIELD OF THE INVENTION uct Sulfur specifications. Additionally, most conventional catalytic refining and petrochemical processes cannot be used The present invention relates to a process for desulfurizing on these heavy feedstocks and intermediates due to their use bitumen and other heavy oils such as low API gravity, high 10 offixed bed catalyst systems and the tendency of these heavy Viscosity crudes, tar sands bitumen, or shale oils with alkali hydrocarbons to produce excessive coking and deactivation metal compounds under conditions to promote in-situ regen of the catalyst systems when in contact with Such feed eration of the alkali metal compounds. The present invention streams. Also, due to the excessive hydrocarbon unsaturation employs the use of Superheated water and hydrogen under and cracking of carbon-to-carbon bonds experienced in these conditions to improve the desulfurization and alkali metal 15 processes, significant amounts of hydrogen are required to hydroxide regeneration kinetics at Sub-critical temperatures. treat asphaltene containing feeds. The high consumption of hydrogen, which is a very costly treating agent, in these DESCRIPTION OF RELATED ART processes results in significant costs associated with the con ventional catalytic hydrotreating of heavy oils for sulfur As the demand for hydrocarbon-based fuels has increased, removal. the need for improved processes for desulfurizing hydrocar Due to their high Sulfur content, high viscosities, and low bon feedstocks of heavier molecular weight has increased as API gravities, these heavy hydrocarbon feedstreams cannot well as the need for increasing the conversion of the heavy be readily transported over existing pipeline systems and are portions of these feedstocks into more valuable, lighter fuel often severely discounted for use as a feedstock for producing products. These heavier, “challenged’ feedstocks include, but 25 higher value products. Another alternative utilized is to make are not limited to, low API gravity, high Sulfur, high viscosity these heavy oils Suitable for pipeline transportation or petro crudes from such areas of the world as Canada, the Middle chemical feed only after significant dilution of the heavy oil East, Mexico, Venezuela, and Russia, as well as less conven with expensive, lower sulfur hydrocarbon diluents. tional refinery and petrochemical feedstocks derived from Therefore, there exists in the industry a need for an Such sources as tar sands bitumen, coal, and oil shale. These 30 improved process for removing Sulfur from bitumens, heavy heavier crudes and derived crude feedstocks contain a signifi crudes, derived crudes and refinery residual streams without cant amount of heavy, high molecular weight hydrocarbons. requiring the use of structured catalysts or significant hydro A considerable amount of the hydrocarbon of these heavy oil gen consumption. streams are often in the form of large multi-ring hydrocarbon molecules and/or a conglomerated association of large mol 35 SUMMARY OF THE INVENTION ecules containing a large portion of the Sulfur, nitrogen and metals in the hydrocarbon stream. A significant portion of the The current invention is a process for desulfurizing a Sul sulfur contained in these heavy oils is in the form of heteroa fur-containing heavy oil feedstream to produce a product toms in polycyclic aromatic molecules, comprised of Sulfur stream with a reduced sulfur content. In preferred embodi compounds Such as dibenzothiophenes, from which the Sul 40 ments, the Viscosity of the produced product stream is fur is difficult to remove. reduced and the API gravity of the produced product stream is The high molecular weight, large multi-ring aromatic increased thereby resulting in a heavy oil product stream with hydrocarbon molecules or associated heteroatom-containing improved properties for use in Such applications as pipeline (e.g., S.N.O) multi-ring hydrocarbon molecules in the heavy transportation or petroleum refining. oils are generally found in a solubility class of molecules 45 An embodiment of the present invention is a process for termed as asphaltenes. A significant portion of the Sulfur is removing Sulfur from a sulfur-containing heavy oil feed contained within the structure of these asphaltenes or lower stream, comprising: molecular weight polar molecules termed as “polars' or “res a) contacting a Sulfur-containing heavy oil feedstream with ins'. Due to the large aromatic structures of the asphaltenes, a hydrogen-containing gas and potassium hydroxide in a the contained Sulfur can be refractory in nature and is not very 50 susceptible to removal by conventional alkali salt solution Superheated water Solution in a reaction Zone to produce a complexes such as potassium hydroxide or sodium hydroxide reaction effluent stream; Solution treatments under conventional operating conditions.