MXPA06001864A - Treatment of crude oil fractions, fossil fuels, and products thereof - Google Patents

Abstract

In crude oil fractions, fossil fuels, and organic liquids in general in which it is desirable to reduce the levels of sulfur-containing and nitrogen-containing components, the process reduces the level of these compounds via the application of heat, an oxidizing agent and, preferably, sonic energy. The invention is performed either as a continuous process or a batch process, and may further include optional steps of centrifugation or hydrodesulfurization.

Description

TREATMENT OF FRACTIONS OF RAW OIL, FOSSIL FUELS AND PRODUCTS THEREOF Field of the Invention The present invention relates to the field of chemical processes for the treatment of fractions of crude oil and various types of products derived from and obtained from these sources. In particular, the present invention is directed to reforming processes such as ring opening reactions and the saturation of double bonds, to improve fossil fuels and convert organic products to forms that will improve their performance and expand their usefulness. The present invention also relates to the removal of sulfur-containing compounds, nitrogen-containing compounds, and other undesirable components of petroleum and petroleum-based fuels. Background of the Invention Fossil fuels are the largest and most widely used energy source in the world, offering high efficiency, proven performance, and relatively low prices. There are many different types of fossil fuels, ranging from fractions of petroleum to mineral coal, tar sands, oil shale, with uses ranging from consumer uses such as automotive engines and home heating to commercial uses Ref.169939 such as kettles, furnaces, foundry units, and power plants. Fossil fuels and other fractions of crude oil derived from natural sources contain a vast array of hydrocarbons that differ widely in molecular weight, boiling and melting points, reactivity, and ease of processing. Many industrial processes have been developed to improve these materials by removing, diluting, or converting their heavier components or those that tend to polymerize or otherwise solidify, notably the defines, aromatics, and fused ring compounds such as naphthalenes, indanos and indenos, anthracenos, fenantracenos. A common means of effecting the conversion of these compounds is saturation by hydrogenation through double bonds. For fossil fuels in particular, a growing concern is the need to remove sulfur compounds. Sulfur from sulfur compounds causes corrosion in pipes, pumping and refining equipment, the poisoning of catalysts used in the refining and combustion of fossil fuels, and the premature failure of combustion engines. "Sulfur poisons catalytic converters used in trucks and buses driven by diesel to control emissions of nitrogen oxides (NOx)." Sulfur also causes an increase in particulate (soot) emissions from trucks and buses due to the degradation of traps from Soot used in these vehicles Burning sulfur-containing fuel produces sulfur dioxide which enters the atmosphere as acid rain, inflicting damage to agriculture and wildlife, and causing risk to human health The Clean Air Act of 1964 and its various amendments have imposed sulfur emission standards that are difficult to meet.According to the Law, the United States Environmental Protection Agency has established an upper limit of 15 parts per million by weight (ppm by weight ) in the sulfur content of diesel fuel, effective for mid-2006. This is a severe reduction of the 500 ppm standard by weight that came into force in the year 2000. For reformulated gasoline, the standard of 300 ppm by weight in the year 2000 has been reduced to 30 ppm in weight, effective the lo. January 2004. Similar changes have been decreed in the European Union, which has imposed a limit of 50 ppm by weight of sulfur for both gasoline and diesel fuel in 2005. Fuel treatment to achieve sulfur emissions sufficiently low to meet these requirements is difficult and expensive, and the increase in fuel prices that this causes will have a greater influence on the world economy. The main method of desulfurization of fossil fuels in prior techniques is hydrodesulphurisation, that is, the reaction between fossil fuel and hydrogen gas at elevated temperature and pressure in the presence of a catalyst. This causes the reduction of organic sulfur to H? S gas, which is then oxidized to elemental sulfur by the Claus process. However, a considerable amount of unreacted HSS is maintained, with its concomitant health risks. An additional limitation of hydrodesulfurization is that it is not equally effective in the removal of all sulfur-containing compounds. Mercaptans, thioethers, and disulfides, for example, are easy to break down and remove by the process, while aromatic sulfur compounds, cyclic sulfur compounds, and multiclick sulfur compounds have less response to the process. Thiophene, benzothiophene, dibenzothiophene, other thiophenes of condensed rings, and substituted versions of these compounds, which account for as much as 40% of the total sulfur content of crude oils in the Middle East and 70% of the sulfur content of crude oil of the West Texas, are particularly refractory to hydrodesulfurization. In view of the deficiencies associated with hydrodesulfurization, new processes have emerged, the most notable being oxidative desulfurization, which seeks to effect the removal of sulfur with greater efficiency. Essentially, said process involves the oxidation of sulfur species that may be present, typically by the use of an oxidizing agent, such as a hydroperoxide or peracid, to thereby convert the sulfur compounds to sulfones. To facilitate such an oxidative reaction, ultrasound may be applied according to the teachings of U.S. Patent No. 6,402,939 issued to Yen et al. Entitled "Oxidative Desulfurization of Fossil Fuels with Ultrasound".; and United States Patent Number 6,500,219 issued to Gunnerman, entitled Continuous Process for the Oxidative Desulfurization of Fossil Fuels with Ultrasound and Products thereof, the teachings of which are hereby expressly incorporated by reference. Advantageously, oxidative desulphurization can be carried out under moderate temperatures, and typically it does not require hydrogen. Additionally, it is advantageous that oxidative desulphurization requires much less in terms of capital expenditures for its implementation. In this regard, oxidative desulphurization can be selectively deployed to treat only a single fraction or refined petroleum, such as diesel, and can be easily integrated as a termination process in existing refinery facilities. It may be more advantageous that the oxidative desulphurization can substantially eliminate all the sulfur species present in a given amount of crude oil in such a way that ultra-low sulfur levels can be achieved, and in particular the lower standards set forth in Several legislative requirements with respect to sulfur content levels. Despite such advantages, however, oxidative desulfurization is currently without effect for use in large-scale refining operations insofar as the currently deployed oxidative desulfurization techniques only partially oxidize sulfur species present to sulphoxides, as opposed to to the sulfones. In relation to this, current oxidative desulfurization techniques are largely ineffective and can not achieve the sufficient oxidation needed to be implemented on a large scale. Furthermore, to the extent that the sulfur species are only partially oxidized (ie to sulphoxides), the final removal of the sulfur species, which is typically achieved either by solvent extraction or by absorption based on the polarity differential of the sulfones that is supposed to be present throughout this process, fails to facilitate the removal of the sulphoxide components based on their lower degree of polarity (that is, in comparison with sulfones). Consequently, substantial refinements to oxidative desulfurization must be made before such technology can be practically implemented. In addition to the sulfur compounds, it is also sought that the nitrogen-containing compounds are removed from fossil fuels since these compounds tend to poison the acidic compounds of the hydrodisintegration catalysts used in the refinery. The removal of nitrogen-containing compounds is achieved by hydrodesnitrogenation, which is a treatment with hydrogen carried out in the presence of metal sulfide catalysts. Both hydrodesulfurization and hydrodesitrogenation require expensive catalysts as well as high temperatures (typically 204 ° C to 254 °, which is equivalent to 400 ° F to 850 ° F) and pressures (typically from 344.7 kPa to 24,131.6 kPa (50 psi to 3,500 psi)). These processes also require a source of hydrogen or a hydrogen-producing unit in place, which requires high capital expenditures and operating costs. In both processes, there is also a risk of leakage of hydrogen from the reactor. As such, there is a substantial need in the art for systems and methods that are operative to effect the removal of sulfur from refined fossil oils that is substantially effective in removing virtually all sulfur species present in fossil fuel that is also extremely economical and can be easily integrated into conventional oil refining processes. There is similarly a need in the art for a method of this type that is effective in removing nitrogen-containing compounds that is also economical and substantially effective in removing virtually all of the nitrogen species present in that fossil fuel. Even more, there is a need for such a process that is capable of improving the quality of refined fossil fuel treated in this manner and that can be easily used in large scale or small scale refining operations. Brief Description of the Invention It has now been discovered that fossil fuels, crude oil fractions, and many components derived from these sources can undergo a variety of beneficial conversions and can be improved in a variety of ways by a process that applies heat and an oxidizing agent, preferably together with sonic energy to such materials in a reaction medium. The crude oil fraction of fossil fuels is preferably combined with an aqueous phase to form an emulsion to facilitate the reactions that effect the purification and improvement of the desired fossil fuel. Hydrogen gas is not required, but can be used as part of a conventional hydrotreating process to facilitate the removal of contaminants, particularly sulfur and nitrogen. In certain embodiments of the invention, the treatment with sonic energy is carried out in the presence of a hydroperoxide. In some other embodiments, a transition metal catalyst is employed.

However, one of the surprising findings associated with certain embodiments of the present invention is that in some applications the conversions achieved by this invention can be achieved without the inclusion of a hydroperoxide in the reaction mixture. Among the conversions achieved included by the present invention is the removal of organic sulfur compounds, the removal of organic nitrogen compounds, the saturation of double bonds and aromatic rings, and the opening of rings in fused ring structures. The invention additionally lies in processes for converting aromatics to cycloparaffins, and the opening of one or more rings in a fused ring structure, which converts for example naphthalenes to monocyclic aromatics, anthracenes to naphthalenes, fused heterocyclic rings such as benzothiophenes, dibenzothiophenes, benzofuranes, quinolines, indoles, and similar to substituted benzenes, acenaphthalenes and acenaphthalenes to indanes and indenes, and monocyclic aromatics to non-cyclic structures. Still further, the invention lies in processes for converting defines to paraffins, and in processes for breaking carbon-carbon bonds, carbon-sulfur bonds, carbon-metal bonds, and carbon-nitrogen bonds. In addition to the above, API gravities of fossil fuels and crude oil fractions are raised (ie, densities are lowered) as a result of treatments according to the invention. Along with these lines, fossil fuels and fractions thereof treated by means of the processes of the present invention can be easily separated into multiple layers via the application of a conventional centrifugation process by which a light layer low in sulfur can be generated. and to separate from a heavier layer high in sulfur. With this respect, because the processes of the present invention facilitate the oxidation of sulfur, among other compounds, it is caused that such oxidized sulfur compounds, i.e., sulfones, precipitate and therefore remain separated in a layer of crude oil. more heavy. Alternatively, insofar as the sulfur compounds are not oxidized and / or if an oxidizing agent is not used in the process of the present invention, it can still cause the sulfur to be retained in the crude oil layer more. heavy following the application of centrifugal force, particularly when it causes it to generate a heavier layer of asphaltene resin. In addition, the invention raises the cetane number of petroleum fractions and cracking products whose boiling points or ranges are in the range of diesel. The term "diesel range" is used here in the industry sense to denote the portion of the crude oil that distills after naphtha, and generally in the temperature range of about 200 ° C (392 ° F) to 370 ° C (698 ° F). Fractions and cracking products whose boiling ranges are contained within this range are included, as well as those that overlap with this range to a greater degree. Examples of fractions and refinery streams within the diesel range are fluid catalytic cracking (FCC) cyclic oil fractions, coker distillate fractions, primary distillation diesel fractions, and mixtures. The invention also imparts other beneficial changes such as a decrease in boiling points and a removal of components that are detrimental to fuel performance and those that affect the refinery processes and increase the cost of producing the fuel. Therefore, for example, FCC cyclic oils can be treated in accordance with the invention to markedly reduce their aromatics content. An additional group of fractions of crude oil for which the invention is particularly useful is that of gas oils, whose term is used here as in the oil industry, to denote liquid petroleum distillates that have higher boiling points than naphtha. The initial boiling point can be as low as 200 ° C (400 ° F), but the preferred boiling range is from about 260 ° C (500 ° F) to about 595 ° C (1100 ° F). Examples of fractions that boil within this range are oil with suspended FCC particles, light and heavy gas oils, so called in view of their different boiling points, and coke oil gas oils. All terms in this paragraph and in the preceding paragraph are used here as it is done in petroleum technology. By virtue of the conversions that take place as a result of the process of this invention, the hydrocarbon streams undergo changes in their cold flow properties, including their runoff points, cloud points, and freezing points. Sulfur compounds, nitrogen compounds, and metal-containing compounds are also reduced, and the use of a process in accordance with the present invention significantly reduces the load on commercial processes such as hydrodesulfurization, hydrodesnitrogenation, and hydrodemetalization, which therefore they can perform more effectively and efficiently. These and other advantages, features, applications and embodiments of the invention are made more apparent by the following description. Detailed Description of the Invention The term "liquid fossil fuel" is used herein to denote any carbonaceous liquid that is derived from petroleum, coal, or any other material present in nature, as well as processed fuels such as gas oils and products from fluid catalytic cracking, hydrodisintegration units, thermal cracking units, and cokers, and which are used to generate energy for any type of use, including industrial uses, commercial uses, governmental uses, and consumer uses. These fuels include automotive fuels such as gasoline, diesel fuel, turbojet fuel, and rocket fuels, as well as fuel oils based on petroleum residues including ship fuels and residual fuels. Fuel oil No. 6, for example, which is also known as fuel oil for "Vessels C", is used in power plants that burn oil as the main fuel and which is also used as main propulsion fuel in draft vessels deep in the navigation industry. Fuel oil No. 4 and fuel oil No. 5 are used to heat large buildings such as schools, apartment buildings, and office buildings, and large stationary marine engines. The heaviest fuel oil is the vacuum residue of fractional distillation, commonly referred to as "vacuum residue", with a boiling point of 565 ° C and above, which is used as asphalt and fed to the coker. The present invention is useful in the treatment of any of these fuels and fuel oils for purposes of reducing sulfur content, nitrogen content, and aromatics content, and for general improvement of quality to improve performance and utility. enhanced Certain embodiments of the invention include the treatment of fractions or products in the diesel range which includes, but is not limited to, primary distillation diesel fuel, commercial diesel fuel (commercially available to consumers in gas stations), light cyclic oil , and mixtures of primary distillation diesel and light cyclic oil varying in proportions from 10:90 to 90:10 (primary distillation diesel: light cyclic oil). The term "crude oil fraction" is used here to denote any of several refinery products produced from crude oil, either by atmospheric distillation or vacuum distillation, including fractions that have been treated by hydrodisintegration, catalytic cracking, thermal cracking, or coking, and those that have been desulfurized. Examples are light primary distillate naphtha, heavy primary distillate naphtha, light steam cracked naphtha, light thermal cracking naphtha, light catalytic cracking naphtha, heavy thermal cracked naphtha, reformed naphtha, alkylated naphtha, kerosene, hydrotreated kerosene, gasoline and light gasoline from primary distillation, primary distillation diesel, atmospheric gas oil, light vacuum gas oil, vacuum heavy gas oil, residue, vacuum residue, light coke gasoline, coking distillate, FCC cyclic oil (fluid catalytic cracking) , and oil with FCC suspended particles. The term "fused ring aromatic compounds" is used herein to denote compounds containing two or more fused rings wherein at least one of them is a phenyl ring, with or without substituents, and including compounds in which all fused rings are phenyl or hydrocarbyl rings as well as compounds in which one or more of the fused rings are heterocyclic rings. Examples are substituted and unsubstituted naphthalenes, anthracenes, benzothiophenes, dibenzothiophenes, benzofurans, quinolines, and indoles. The term "olefins" is used herein to denote hydrocarbons, especially those containing two or more carbon atoms and one or more double bonds. Fossil fuels and fractions of crude oil treated in accordance with the present invention have significantly improved properties in relation to the same materials before treatment, these improvements make the products unique and improve their usefulness as fuels. Specifically, the present invention is operative to open aromatic compounds of fused rings by converting them to saturated compounds. Such a process is similarly operative to convert olefins to saturated compounds in such a way that at least one or more of the double bonds present are replaced by single bonds. Another of these improved properties by means of the present invention is API gravity. The term "API" gravity is used here as it is used among those with experience in petroleum and petroleum-derived fuels. In general, the term represents a scale of measurement adopted by the American Petroleum Institute, the values in the scale are increased by decreasing the values of specific gravity. Therefore a relatively high API gravity means a relatively low density. The API severity scale extends from -20.0 (equivalent to a specific gravity of 1.2691) to 100.0 (equivalent to a specific gravity of 0.6112). The process of the present invention is applicable to any liquid fossil fuel, preferably those with API gravities in the range of -10 to 50, and more preferably in the range of 0 to 45. For materials boiling in the range of diesel, the The process of the invention is preferably carried out in such a way that the starting materials are converted to products with API gravities in the range of 37.5 to 45. FCC cyclic oils are preferably converted to products with API gravities in the range of 30 to 50. For liquid fossil fuels in general, the process of the invention is preferably carried out to achieve an increase in API gravity in an amount ranging from 2 to 30 API gravity units, and more preferably in an amount ranging from 7 to 25 units. . Alternatively expressed, the invention preferably increases API gravity from less than 20 to more than 35. As stated above, fossil fuels boiling in the range of diesel that are treated in accordance with the present invention experience an improvement in its cetane number (also referred to in the art as "cetane number") when treated in accordance with the present invention. The diesel fuels for which the invention is of particular interest in this regard are those which have a cetane number greater than 40., preferably in the range of 45 to 75, and more preferably in the range of 50 to 65. The improvement in the cetane number can also be expressed in terms of an increase with respect to the material before treatment by the process described in the present. In certain preferred embodiments, the increase is in an amount ranging from 1 to 40 units of cetane number, and more preferably in an amount ranging from 4 to 20 units. Still as a further means of expression, the invention preferably increases the cetane number from less than 47 to about 50. The present invention can be used to produce diesel fuels having a cetane number greater than 50.0, or preferably greater than 60.0. In terms of ranges, the invention is capable of producing diesel fuels having a cetane number from about 50.0 to about 80.0, and preferably from about 60.0 to about 70. The cetane number or number has the same meaning in this specification and in the appended claims that he has among those with experience in the automotive fuel technique. As indicated above, certain embodiments of the invention involve the inclusion of hydroperoxide in the reaction mixture. The term "hydroperoxide" is used herein to denote a compound of the molecular structure: R-O-O-H in which R represents either a hydrogen atom or an organic or inorganic group. Examples of hydroperoxides in which R is an organic group are water-soluble hydroperoxides such as methyl hydroperoxide, ethyl hydroperoxide, isopropyl hydroperoxide, n-butyl hydroperoxide, sec-butyl hydroperoxide, tert-butyl hydroperoxide, hydroperoxide 2-methoxy-2-propyl, ter-amyl hydroperoxide, and cyclohexyl hydroperoxide. Examples of hydroperoxides in which R is an inorganic group are peroxonitrous acids, peroxyphosphoric acid, and peroxosulfuric acid. Preferred hydroperoxides are hydrogen peroxide (in which R is a hydrogen atom) and tertiary alkyl peroxides, mainly tert-butyl peroxide.

The aqueous fluid that can be optionally combined with the fossil fuel or other liquid organic starting material in the processes of the present invention can be water or any aqueous solution. The relative amounts of the organic and aqueous phases may vary, and although they may affect the efficiency of the process or the ease of handling of the fluids, the relative amounts are not critical to the present invention. In this respect, it is contemplated that the aqueous fluid may be present in any amount from about 0% to 99% by weight of the combined organic and aqueous phases. However, in most cases, better results will be achieved when the volume ratio of the organic phase to the aqueous phase is from about 8: 1 to about 1: 5, preferably from about 5: 1 to about 1: 1, and more preferably from about 4: 1 to about 2: 1. Although it is optional, when a hydroperoxide is present, the amount of hydroperoxide relative to the organic and aqueous phases may vary, and although the conversion rate and yield may vary to some extent with the proportion of hydroperoxide, the actual proportion is not critical to the invention, and any excess amount will be eliminated by the application of sonic energy. For example, when the amount of H202 is calculated as a component of the combined organic and aqueous phases, generally favorable results will be achieved in most systems with H202 being present in the range of about 0.0003% to about 70% by volume ( as H202), and preferably from about 1.0% to about 20% of the combined phases. For hydroperoxides other than H202, the preferred concentrations will be those of the equivalent amounts. In certain embodiments of the present invention, a surface active agent or other emulsion stabilizer is included to stabilize the emulsion. Certain fractions of the oil contain surface active agents as components of the naturally occurring fractions, and these agents can serve themselves to stabilize the emulsion. In other cases, synthetic surface active agents or those that are not naturally present can be added. Any of the wide variety of known materials that are effective as emulsion stabilizers can be used. A listing of these materials is available in McCutcheon Volume 1: Emulsifiers and Detergents - 1999 North American Edition, McCutcheon Division, MC Publishing Co. , Glen Rock, New Jersey, USA, and other published literature. Cationic, anionic surfactants and non-ionic surfactants can be used. Preferred cationic species are quaternary ammonium salts, quaternary phosphonium salts and crown ethers. Examples of quaternary ammonium salts are tertrabutil ammonium bromide, tetrabutyl ammonium hydrogen sulfate, tributylmethyl ammonium chloride, benzyltrimethylammonium chloride, benzyltriethylammonium chloride, methyltricaphenyl ammonium chloride, dodecyltrimethyl ammonium bromide, tetraoctyl ammonium bromide, cetyltrimethyl ammonium chloride , and trimethyloctadecyl ammonium hydroxide. Quaternary ammonium halides are useful in various systems, and most preferred are dodecyltrimethyl ammonium bromide and tetraoctyl ammonium bromide. Preferred surface active agents are those which will promote the formation of an emulsion between the organic and aqueous phases by passing the liquids through a common mixing pump, but which will spontaneously separate the product mixture into aqueous and organic phases for immediate separation by decantation or other simple phase separation procedures. One class of surface active agents that will achieve this are C 5 5-C20 liquid aliphatic hydrocarbons and mixtures of such hydrocarbons, preferably those having a specific gravity of at least about 0.82 and more preferably at least about 0.85. Examples of hydrocarbon mixtures that meet this description and are particularly suitable for use and are readily available are mineral oils, preferably heavy or extra heavy mineral oil. The terms "mineral oil", "heavy mineral oil" and "extra heavy mineral oil" are well known in the art and are used herein in the same manner as are commonly used in the art. Such oils are readily available from suppliers of commercial chemicals throughout the world. When an added emulsifying agent is used in the practice of the present invention, the appropriate amount of agent to use is any amount that will perform as described above. Otherwise the quantity is not critical and may vary depending on the choice of agent, and in the case of mineral oil, the grade of the mineral oil. The amount may also vary with the composition of the fuel, the relative amounts of the aqueous and organic phases, and the operating conditions. The appropriate selection will be a matter of choice and routine adjustment for the experienced engineer. In the case of mineral oil, generally better and more efficient results will be obtained by using a volume ratio of mineral oil to organic phase 1 of about 0.00003 to about 0.003.

In certain embodiments of the invention, a metal catalyst may be included in the reaction system to regulate the activity of the hydroxyl radical produced by the hydroperoxide. Examples of such catalysts are transition metal catalysts, and preferably metals having atomic numbers from 21 to 29, 39 to 47, and 57 to 79. Particularly preferred metals of this group are nickel, sulfur, tungsten (and tungstates), cobalt, molybdenum, and combinations thereof. In certain systems within the scope of the present invention, Fenton catalysts (ferrous salts) and metal ion catalysts in general such as iron (II), iron (III), copper (I), copper (II) ions are useful. ), chromium (III), chromium (VI), molybdenum, tungsten, cobalt, and vanadium. Of these, catalysts are iron (II), iron (III), copper (II), and tungsten. For some systems, such as crude oil, Fenton type catalysts are preferred, while in others, such as in systems containing diesel, tungsten or tungstates are preferred. Tungstates include tungstic acid, substituted tungstic acids such as phosphotungstic acid, and metal tungstates. In certain embodiments of the invention, nickel, silver, or tungsten, or combinations of these three metals are particularly useful. The metal catalyst when present will be used in a catalytically effective amount, which means any amount that will improve the progress of the reaction (i.e., increase the reaction rate) towards the desired objective, particularly the oxidation of the sulfides to sulfones. The catalyst may be present as metal particles, granules, flakes, chips, or other similar forms, retained in the sonic energy supply chamber by means of physical barriers such as meshes or other restraining means by passing through them the reaction medium. Of the aforementioned catalysts, phosphotungstic acid or a mixture of sodium tungstate is included among the most preferred and phenylphosphonic acid can be used based on a lower price and easy availability in bulk. It should be understood, however, that the use of such catalysts is optional and required for someone skilled in the art to practice the present invention. The temperature of the combined aqueous and organic phases can vary widely, although in most cases it is contemplated that the temperature will rise to about 500 ° C, preferably up to about 200 ° C, and most preferably up to not more than 125 ° C. C. The optimum degree of heating will vary with the particular organic liquid to be treated and the ratio of the organic aqueous phases, provided that the temperature is not high enough to volatilize the organic liquid. With diesel fuel, for example, better results will often be obtained by preheating the fuel to a temperature of at least about 70 ° C, and preferably from about 70 ° C to about 100 ° C. The aqueous phase can be heated to any temperature up to its boiling point. Although optional, the sonic energy used in accordance with the present invention consists of waves similar to those of sound whose frequency is within the range of about 2 kHz to about 100 kHz, and preferably within the range of about 10 kHz to about 19 kHz . In a much preferred mode, the sonic energy used has a frequency in the range of approximately 17 kHz to 19 kHz. As will be appreciated by those skilled in the art, such sonic waves can be generated from known mechanical, electrical, electromagnetic, or other sources of energy. With this regard, the various methods of production and application of sonic energy, and of commercial suppliers of sonic energy production equipment, they are well known among those with experience in the art. Example of such systems capable of being used in the practice of the present invention to impart the necessary degree of sonic energy described herein include ultrasonic systems produced by Hielscher Systems of Teltow, Germany and distributed domestically through Hielscher USA, Inc. of Ringwood, New Jersey. The intensity of the applied sonic energy will preferably have a sufficient magnitude to facilitate the oxidation of at least a portion of the sulfur and nitrogen species present in the fossil fuel being treated, as well as to open the fused ring compounds and saturate the compounds olefins that may be present. Currently, it is believed that the applied sonic energy should have an amplitude of displacement in the range of about 10 to 300 micrometers, and can be adjusted according to how the process of the present invention is conducted either at temperatures and / or at high pressures. To the extent that the processes of the present invention are carried out at room temperature and pressure, an amplitude of displacement ranging from about 30 to 120 microns may be appropriate, with a range of about 36 to 60 microns being preferred. The preferred range of energy to be delivered per unit volume (i.e., energy density) should preferably be in the range of about 0.01 watts per cubic centimeter to about 100.00 watts per cubic centimeter of treated liquid, and preferably about 1 watt per cubic centimeter at approximately 20 watts per cubic centimeter of treated liquid. It should be understood, however, that higher energy densities could be achieved, given the ability of the existing equipment to produce an output of energy as high as 15 kilowatts, and that higher output of energy can be used to facilitate the reactions of the present invention. The exposure time of the reaction medium to the sonic energy is not critical to the practice or to the success of the invention, and the maximum exposure time will vary according to the type of fuel being treated. However, an advantage of the invention is that effective and useful results can be achieved with a relatively short exposure time. A preferred range of exposure times is from about 1 second to about 30 minutes, and a more preferred range is from about 1 second to 1 minute, with excellent results being obtained with exposure times of approximately 5 seconds and possibly less. For the desired degree, improvements in the efficiency and effectiveness of the process can also be achieved through recycling or secondary treatments with sonic energy. A fresh supply of water may for example be added to the organic phase treated and separated to form a fresh emulsion which is then exposed to an additional treatment of sonic energy, either batchwise or continuously. The re-exposure to sonic energy can be repeated several times for even better results, and can be easily achieved in a continuous process by means of a recycle stream or by the use of a second stage of sonic energy treatment, and possibly a third stage of sonic energy treatment, with a fresh supply of water in each stage.

In systems in which the reaction induced by the application of sonic energy produces undesirable byproducts in the organic phase, these by-products can be removed by conventional methods of extraction, absorption, or filtration. When the by-products are polar compounds, for example, the extraction process can be any process that extracts polar compounds from a non-polar liquid medium. Such processes include solid-liquid extraction, using absorbers such as silica gel, activated alumina, polymer resins, and zeolites. Liquid-liquid extraction can also be used, with polar solvents such as dimethyl formamide, N-methylpyrrolidone, or acetonitrile. A variety of organic solvents can be used that are either miscible or marginally miscible with fossil fuel. Examples are toluene and similar solvents. Alternatively, to the extent that any desirable byproduct is produced in the organic phase which consists of oxidized nitrogen and sulfur containing species, such as sulfoxides and sulfones, these may be treated in accordance with conventional hydrodesulfurization processes. In this respect, the oxidative processes of the present invention can be incorporated into those processes described in U.S. Patent Application Serial Number 10 / 411,796, filed on April 11, 2003, entitled Sulfone Removal Process, and U.S. Patent Application Serial Number 10 / 429,369 filed May 5, 2003, entitled Process for Generating and Removing Fossil Fuel Sulphides, the teachings of each of which are hereby expressly incorporated by reference. To facilitate the removal of the sulfur-containing compounds, the processes of the present invention can additionally incorporate the use of the centrifuge application, which advantageo causes the fossil fuels treated in accordance with the present invention to be sorted or stratified in layers of variable density. Specifically, following the process discussed above whereby it is suspected that fossil fuels contain sulfur they are subjected to the application of ultrasound and an oxidizing agent, the resulting fossil fuel can then be subjected to a centrifugation stage which will produce a light layer (ie, of lower density) that has a low sulfur content and a heavy (ie, denser) layer that has a higher concentration of sulfur. In this regard, to the extent that any of the sulfur-containing compounds present in the fossil fuel are oxidized to become sulfones, such sulfones will precipitate in the heavy layer. Alternatively, to the extent that an oxidizing agent is not used and / or the sulfur is not oxidized, it is nevertheless believed that the sulfur will still precipitate in the heavier and denser layer, particularly if a fraction of crude oil is centrifuged. which results in the production of a heavy asphaltenic resin layer. In this regard, it is contemplated that the application of a centrifugal type force is operative to not only facilitate the stratification of such layers, but also possibly operative to chemically break up any resin present in order to allow such separation to take place, and also decrease possibly the amount of asphaltenes present in that fossil fuel. The results of such a crude oil fraction, and in particular several components thereof treated by centrifugation, which have been previo subjected to ultrasound at approximately 19 kHz for approximately eight minutes at 15.5 ° C (60 minutes), are presented in Table 1 below. ° F) in the presence of 2.5% hydrogen peroxide. Following the application of such an oxidant process and the application of centrifugation, a light layer was generated which was extracted and compared with the previo centrifuged composition.

TABLE 1 Reactions resulting from the processes of the present invention can generate heat, and with certain starting materials it may be preferable to remove some of the heat generated to maintain control over the reaction. When treating gasoline in accordance with the present invention, for example, it is preferable to cool the reaction medium when it is subjected to sonic energy. Cooling can be easily achieved by conventional means, such as the use of a cooling jacket with liquid or a refrigerant circulating through a cooling coil inside the chamber where the sonic energy is deployed. Water at atmospheric pressure is an effective refrigerant for these purposes. Suitable cooling methods or devices will be readily apparent to those skilled in the art. Cooling is usually unnecessary with diesel fuel, gas oils and waste. The operating conditions in general for the practice of the present invention can vary widely, depending on the organic material being treated and the manner in which the treatment is made. The pH of the emulsion, for example, can vary from very low as 1 to very high as 10, although it is currently believed that the best results can be achieved in a pH range of 2 to 7. The pressure of the emulsion as is subjected to sonic energy can vary in the same way, varying from subatmospheric pressure (as low as 0.34 atmospheres or 5 psia) to as high as 214 atmospheres (3,000 psia), although it is preferred to be less than approximately 27 atmospheres (400 psia) , and more preferably less than about 3.4 atmospheres (50 psia), and more preferably from about atmospheric pressure to about 3.4 atmospheres (50 psia). The operating conditions described in the preceding paragraphs that relate to the application of sonic energy, the inclusion of emulsion stabilizers and catalysts, and the general conditions of temperature and pressure apply to the process of the invention regardless of whether or not peroxide is present of hydrogen or any other hydroperoxide in the reaction mixture. One of the unique and surprising discoveries of the present invention is that when sonic energy is used in the aforementioned process, the levels of sulfur-containing compounds and of nitrogen-containing compounds are substantially reduced regardless of whether a hydroperoxide is present. In addition, the process as described herein can be carried out either batchwise or in a continuous flow operation. Similarly, it has unexpectedly been discovered that even to the extent that sonic energy is not used in the practice of the present invention, and that the process described herein simply uses the combination of heat, heat in combination with an oxidizing agent, and / or With the additional application of centrifugation and / or hydrodesulfurization, numerous objectives (eg, removal of sulfur and nitrogen, and improvement of the fuel properties) of the present invention can be easily achieved in an extremely economical and efficient manner. Further modifications and improvements of the present invention may also be apparent to those skilled in the art. Therefore, the particular combination of parts and steps described and illustrated herein are intended to represent only certain embodiments of the present invention, and are not intended to serve as limitations of alternative devices and methods in the spirit and scope of the invention. It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims (3)

2. Having described the invention as above, the content of the following claims is claimed as property. A process for treating a crude oil fraction to reduce the levels therein of both sulfur-containing compounds and nitrogen-containing compounds, characterized in that the process comprises the steps of: (a) mixing a hydroperoxide with the fraction of Crude oil to form a first mixture and heat that mixture, the mixture is heated sufficiently to oxidize most of the sulfur-containing compounds and a majority of those nitrogen-containing compounds present in the crude oil fraction; and (b) separating the oxidized sulfur containing compounds produced in step (a) and separating the oxidized nitrogen containing compounds produced in step (a) of the crude oil fraction. 2. The process according to claim 1, characterized in that in step (b), the oxidized sulfur containing compounds and the oxidized nitrogen containing compounds are separated via hydrodesulfurization. 3. The process according to claim 1, characterized in that in step (b), the compounds containing oxidized sulfur are separated via centrifugation. 4. The process according to claim 1, characterized in that step (a) further comprises exposing said mixture to sonic energy. The process according to claim 3, characterized in that the separation of the oxidized sulfur compounds using centrifugation is operative to produce at least a first layer having a first sulfur content and a first density and at least a second layer having a second sulfur content and a second density, the first concentration of sulfur being lower than the second concentration of sulfur and the first density being less than the second density. 6. The process according to claim 1, characterized in that the crude oil fraction is a fraction boiling within the range of diesel. The process according to claim 4, characterized in that the crude oil fraction is a member selected from the group consisting of fluid catalytic cracking cyclic oil fractions, coking distillate fractions, primary distillation diesel fractions, and mixtures thereof. 8. The process according to claim 1, characterized in that the crude oil fraction is a boiling fraction within the range of gas oils. The process according to claim 6, characterized in that the crude oil fraction is a member selected from the group consisting of cyclic oil from fluid catalytic cracking, oil with suspended particles from fluid catalytic cracking, light gas oil, heavy gas oil, and Coke oil gas. The process according to claim 1, characterized in that the crude oil fraction is a member selected from the group consisting of gasoline, turbojet fuel, primary distillation diesel, primary distillation diesel blends and light cracking cyclic oil fluid catalytic, and fuel oil based on oil residues. 11. The process according to claim 4, characterized in that in step (a) the fraction of the crude oil is exposed to sonic energy from about 1 second to about 1 minute. The process according to claim 1, characterized in that it additionally comprises contacting the emulsion with a transition metal catalyst during step (a). The process according to claim 12, characterized in that the transition metal catalyst is a member selected from the group consisting of metals having atomic numbers from 21 to 29, 39 to 47, 57 to 79. 14. The process in accordance with claim 12, characterized in that the transition metal catalyst is a member selected from the group consisting of nickel, silver, tungsten, cobalt, molybdenum, and combinations thereof. 15. The process according to claim 12, characterized in that the transition metal catalyst is a member selected from the group consisting of nickel, silver, tungsten, and combinations thereof. 16. The process according to claim 1, characterized in that in step (a), the mixture is heated to a temperature not higher than 500 ° C. 17. The process according to claim 1, characterized in that in step (a), the mixture is heated to a temperature not higher than 200 ° C. 18. The process according to claim 1, characterized in that in step (a), the mixture is heated to a temperature not higher than 125 ° C. 19. The process according to claim 1, characterized in that step (a) is carried out at a pressure of less than 27.2 atmospheres (400 psia). The process according to claim 1, characterized in that step (a) is carried out at a pressure of less than 3.4 atmospheres (50 psia). 21. The process according to claim 1, characterized in that step (a) is carried out at a pressure within the range of about atmospheric pressure to about
3. 3.4 atmospheres (50 psia).