MXPA00001429A - Process for reducing total acid number of crude oil - Google Patents

Abstract

The invention comprises a method for reducing the amount of carboxylic acids in petroleum feeds comprising the steps of (a) adding to said petroleum feed a catalytic agent comprising an oil soluble or oil dispersible compound of a metal selected from the group consisting of Group VB, VIB, VIIB and VIII metals, wherein the amount of metal in said petroleum feed is at least about 5 wppm, (b) heating said petroleum feed with said catalytic agent in a reactor at a temperature of about 400 to about 800°F (about 204.44 to about 426.67°C), under a hydrogen pressure of 15 psig to 1000 psig (204.75 to 6996.33 kPa), and (c) sweeping the reactor containing said petroleum feed and said catalytic agent with hydrogen-containing gas at a rate sufficient to maintain the combined water and carbon dioxide partial pressure below about 50 psia (about 344.75 kPa).

Description

PROCESS TO REDUCE THE TOTAL ACID NUMBER OF THE CRUDE OIL FIELD OF THE INVENTION The present invention is directed to a method for reducing the Total Acid Number (TAN) of crude oils, a number which is based on the amount of carboxylic acids, especially naphthenic acids, which are present in the petroleum.

BACKGROUND OF THE INVENTION The presence of relatively high levels of petroleum acids, e.g. , naphthonic acids, in crude oils or fractions thereof is a problem for oil refiners and more recently also for producers. Essentially, these acids, which are found to a greater or lesser degree in virtually all crude oils, are corrosive, tend to cause equipment failure, and lead to high maintenance costs, more frequent turns than would otherwise be necessary. , reduce the quality of the product, and cause problems of environmental waste. A very significant amount of literature, both patents cpmo publications, exists, which deals with the removal of naphthenic acid by conversion or absorption. For example, many aqueous materials can be added to crude or crude fractions to convert naphthonic acids into some other material, eg, salts, which can be removed or are less corrosive. Other methods for removal of naphthenic acid are also well known, including absorption, in zeolites, for example. Additionally, a common practice for overcoming the problems of naphthenic acid is the use of alloys resistant to. corrosion, costly, in refinery equipment or producer, who will find relatively high concentrations of naphthonic acid. Another common practice involves mixing the crude with high TAN with crude oil of 'TAN inferior, the latter, however, being significantly more expensive than the former. A reference. Lazar, et al (US 1,953,353) teaches the decomposition of naphthenic acid from primary distillate crudes or distillates, carried out at atmospheric pressure between 315.6 a- 398.9.SC. However, it only recognizes COz as the only decomposition product of naphthenic, non-hydrocarbon, gaseous acid and makes no provision to prevent the accumulation of reaction inhibitors. Additionally, the Patent of E.U.A. No. 2,921,023 describes the removal of naphthenic acids a - j - from heavy oil fractions _ by hydrogenation with a catabolization of molybdenum oxide on silica / alumina. More specifically, the preference process hydrogenates oxo compounds and / or olifin compounds, for example, naphthonic acids, in the presence of sulfur compounds contained in organic mixtures without affecting the sulfur compounds. This is achieved by subjecting the organic mixture to the action of hydrogen at temperatures between about 232.2 to 315.6aC, - in the presence of a catalyst containing molybdenum oxide having a reversible water content - of less than about 1.05 by weight. The life of the catalyst is extended by regeneration. WQ 96/06899 describes a process "-to remove essentially naphthonic acids from a hydrocarbon oil.The process includes hydrogenation at 1 to 50 bar (100 to 5000 kPa) and 100 to 300SC of a crude oil that has not been distilled previously. or from which a naphtha fraction has been distilled using a catalyst consisting of Ni-Mo or Co-Mo on an alumina carrier. The specification describes the pumping of hydrogen into the reaction zone. There is no mention of controlling the water or the partial pressure of carbon dioxide. The Patent of E.U.A. 3,617,501 describes an integrated process for refining whole crude, but does not discuss the reduction of TAN. The first step of the process includes hydrotreating a feed, which can be a complete crude oil fraction, using a catalyst comprising one or more metals supported on a carrier material. Preferably, the metals are metal oxides or sulphides, such as molybdenum, tungsten, cobalt, nickel and iron supported on a suitable carrier material such as alumina or alumina which contains a small amount of silica. The catalyst can be used in the form of a fixed bed, a suspension or a fluidized bed reactor. With respect to the suspension operation, no mention is made of catalyst particle size, catalyst concentration in the feed or the use of unsupported catalysts (ie, no carrier). British Patent 1,236,230 describes a process for the removal of naphthenic acids from petroleum distillate fractions by processing on hydrotreating catalysts supported without the addition of gaseous hydrogen. No mention is made of "control of water or partial pressure of carbon dioxide." U.S. Patent Nos. 4,134,825; 4,740,295; 5,039,392; and 5,620,591, all of which are incorporated herein by reference, teach the preparation of unsupported, highly dispersed catalysts of nominal particle size from an icometer, from oil-soluble or oil-dispersible compounds of selected metals to from groups IVB, VB, VIB, VIIB and VIII of the periodic table of elements and application of said catalysts for the improvement of hydroconversion of heavy feeds, including whole oil crudes or primary distillation. Hydroconversion is defined in these patents as a catalytic process conducted in the presence of hydrogen, wherein at least a portion of the heavy constituents and coke precursors (ie, "Gonradson carbon") are converted to lower boiling compounds. The broader scales cited in these references with respect to process conditions include temperatures in the range of 339.9 to 480SC, partial pressures of hydrogen ranging from 446.08 to 34516.33 kPa, and 10-2000 ppm by weight of catalyst-based metal. the weight of the feeding material. These references are directed to the conversion of heavy feed improvements and do not recognize that the catalysts can be used to selectively destroy carboxylic acids, e.g., naphthonic acids. Another method for the removal of these acids includes treatment at temperatures of at least about 204.44aC, preferably at least about 315.56eC while the reaction zone is swept up by an inert gas to remove the indigenous inhibitors a or formed during the However, this approach has the disadvantage of the volatilization of some of the naphthonic acids, which are found in distilled or light petroleum fractions that evaporate instantaneously during the heat treatment. It is important for this method to be used in downstream applications "where it is desirable to destroy acids before fixed pipe ovens, ie, at temperatures of approximately 287.78SC or lower. In this way, the need remains to eliminate or at least substantially reduce the concentration of petroleum acid in crude or fractions thereof which is low cost and friendly to the refinery. This technology would be particularly suitable for crude or fractions where the TAN is approximately 2 mg KOH / gm of petroleum or higher as determined by the D-664 method of ASTM.

COMPENDIUM OF THE INVENTION The present invention is directed to a method for destroying carboxylic acids in whole crudes or crude fractions. The invention comprises a method for reducing the amount of carboxylic acids in petroleum feeds comprising the steps of "(a) adding to the petroleum feed a catalytic agent which comprises a petroleum-soluble or oil-dispersible compound of a metal selected from the group consisting of Group VB metals, -VIB, VIIB and VIII, where the amount of metal in the oil feed is at least 5 ppm by weight, (b) heating the oil feed with the catalytic agent in a reactor at a temperature of about = 204.44 to about 426.67aC, under a hydrogen pressure of 204.75 to 6996.33 kPa, and (c) sweep the reactor containing the oil feed in the catalytic agent with gas containing hydrogen at a rate sufficient to maintain a partial pressure of water and combined carbon dioxide less than about 344.75 kPa. TAN is defined as the weight in milligrams of potassium hydroxide required to neutralize all acidic conditions in one gram of oil. (See method ASTM D-664).

Vacuum waste conversion is defined as the conversion of boiling material greater than 551.67aC to boiling material less than 551.67SC.

BRIEF DESCRIPTION OF THE FIGURE Figure 1 is the partial pressure calculated for water as a function of reactor pressure and gas scavenging rate containing hydrogen for the process of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The present invention eliminates or destroys "carboxylic acids (e.g., naphthenic acids) 'contained in petroleum feeds such as whole crude oils (including heavy crudes) and fractions thereof such as petroleum fractions. Vacuum gas, raw distillates, vacuum residues, atmospheric residues, raw distillates and vacuum gas oils The present method reduces the TAN by at least approximately 405 in the oil feed. at temperatures from about 204.44 to about 426.67aC, more preferably around 232.22 to about 398.892C), and most preferably from about 260.00 to about 343.33aC.) The hydrogen pressures vary from about atmospheric to about 13891.33. kPa, preferably from about 204.75 to about 6996.33 kPa, and more preferably ible of around 446.08 to about 3548.83 kPa. The amount of catalyst, calculated as metal or catalyst metals, used in the process varies from at least about 5, preferably from about 10 to about 1000 parts per million by weight. { ppm by weight) and more preferably from about 25 to 50 ppm by weight of the oil feed being treated. Preferably, during the process of the present invention, less than about 40% of the vacuum residue component of the feed, i.e., the boiling fraction greater than about 55i.67aC, becomes boiling material less than about 551.67sc. , and "more preferably less than about 305 of vacuum residue conversion occurs.The catalyst particle size ranges from about 0.5 to about 10 microns, preferably about 0.5 to 5 microns, and more preferably from about 0.5 to 2.0 microns The catalysts are prepared from precursors, also referred to herein as catalytic agents, such as petroleum-soluble or oil-dispersible compounds of metal compounds of Group VB, VIB, VIIB or VIII and mixtures Of these, suitable catalyst metals and metal compounds are described in the US Patent. No. 4, 134,825 incorporated herein by reference. An example of a petroleum-soluble compound is the metal salt of a naphthonic acid such as co-naphthenate of molybdenum. Examples of petroleum dispersible compounds are phosphomolybdic acid and ammonium heptamolybdate, materials that first dissolve in water. and then dispersed in the oil as a water-in-oil mixture, wherein the droplet size of the water phase is less than about 10 microns. Ideally, a catalyst precursor concentrate is prepared first, wherein the petroleum-soluble or oil-dispersible metal compound (s) is mixed with a portion of the process feed to form a concentrate containing at least about 0, 2% by weight of catalyst metal, preferably about 0.2 to 2.0% by weight of catalyst metal. See, for example, the Patents of E.U.A. Nos. 5,039,392 or 4,740,295 incorporated herein by reference. The resulting precursor concentrate can be used directly in the process or first converted to a metal sulphide concentrate or an activated catalyst concentrate before use. The catalyst precursor concentrate can be converted to a metal sulphide concentrate by treating with elemental sulfur (added to the feed portion used to prepare the concentrate) or with hydrogen sulphide at 148.89 to 204.44-C for 10 - ^. 5 minutes (e.g., see U.S. Patent Nos. 5,039,392; 4,479,295; and 5,620,591 incorporated herein by reference). The metal sulphide concentrate can be converted to catalyst concentrate by heating from 315.56 to 398.89SC for a sufficient time to form the catalyst (e.g., see U.S. Patent Nos. 5,039,392, 4,740,295, and 5,620,591). The concentrate catalyst consists of nano-scale metal sulfide sites distributed in a hydrocarbonaceous matrix that is derived from the petroleum component of the concentrate. The total particle size can be varied, but falls within the range of 0.5 to 10 micrometers, preferably in the range of about 0.5 to 5.0 micrometers and, more preferably, 0.5 to 2.0 micrometers. For the present process, the precursor concentrate, the metal sulfide concentrate, or the catalyst concentrate can be used. In each case, the oil feed is mixed with the concentrate to obtain the desired concentration of metal in the feed, ie, at least about 5 ppm by weight, preferably about 10 to 1000 ppm by weight. When the metal sulphide precursor or concentrates are used, the catalyst having a particle size of about 0.5 to 10 microns, preferably 0.5 to 5 microns and more preferably 0.5 to 2.0 microns is formed in the step of process heating in the TAN conversion reactor. Preferred metals include molybdenum, tungsten, vanadium, iron, nickel, cobalt and chromium. For example, heteropolyacids of metals can be used. Molybdenum is particularly well suited to the process of the present invention. Preferred molybdenum compounds are molybdenum naphthenates, molybdenum dithiocarbamate complexes (e.g., see U.S. Patent No. 4,561,964 incorporated herein by reference) , phosphomolybdic acid and molybdenum phosphorodithioate complexes (e.g., MOLYVANÍR) -L, molybdenum di (2-ethylhexyl) phosphorodithioate), supplied by RT Vanderbilt Company Other small particle catalysts that are useful for the practice of the present procinclude metal-rich ash from the controlled combustion of petroleum coke (e.g., see U.S. Patent Nos. 4,169,038; 4,178,227; and 4,204,943 incorporated herein by reference). Finely divided iron-based materials, which satisfy the particle size restrictions noted herein, such as the red-mud from the alumina procng, can also be used. The water vapor and carbon dioxide that result from the decomposition of carboxylic acids act as inhibitors for the decomposition of remaining carboxylic acids. Water is a particularly strong inhibitor. In this way, yes. the feed to the proccontains water, a previous flash evaporation step can be used to remove substantially all the water. Additionally, the trace amounts of the water entering the procwith the feed as well as the water and carbon dioxide formed in the course of the destruction of carboxylic acids must be purged so that the partial prre of water and carbon dioxide in the area of reaction is maintained below about 344.75 kPa, preferably lthan about 206.85 kPa, more preferably, lthan about 137.9 kPa, and, more preferably, lthan about 68.95 kPa. Substantially all the water as used herein means as much water as can be removed by methods known to those skilled in the art. Even if one does not wish to be limited by theory, it seems that the source of water and the formation of carbon dioxide in this TAN destruction proccan be described by the equations that follow. The reduction of garboxylic acids with hydrogen has the potential to provide up to two moles of water per mole of reduced acid (Equation A) or one mole of water per mole of reduced acid (Equation B). The thermal reactions, which can compete with the reduction, yield half a mole of water per mole of acid destroyed (Equation C).

Equation A RCHOOH + 2 H2 > RCH3 + 2H20 Equation B RCHOQH + H2 > RCH2 (OH) 2 > H20 + RCHO RCHO > RH • + CG Equation C RCO. 2RC00H - > H2G + RCO RCO RCO- > R- + CO RCQO- > R- + COa As will be illustrated in the examples that follow, water can have a strong inhibitory effect on the carboxylic acid destruction rate. Carbon dioxide is also an inhibitor but to a much lr degree. To illustrate the water prre build-up potential resulting from the destruction of carboxylic acids under the conditions claimed for the procof the present invention, a hypothetical case was assumed where the TAN of an entire crude oil was reduced from 5.3 to 0.3 by heat treatment within the temperature scale set forth in this invention, and that 1.25 moles of water were produced for each mole of acid that was destroyed. The partial prres calculated for water are shown in Figure 1 as a function of reactor prre and sweep gas regime (i.e., gas containing hydrogen). Note that partial water prres as high as 496.44 kPa or greater can be obtained from the decomposition of acid alone, thus emphasizing the preference to start the procwith a dry feed and to maintain a sweep gas regime to maintain the prre of water within the specified levels. From a procpoint of view, the catalyst can be left in the treated crude (depending on the type of metal and concentration) or removed by conventional means, such as filtration. Another aspect of the present invention relates to the carbon content of "Gonradson's product, that is, the components of the product that provide coke under pyrolysis conditions., such as Visrotura, the Conradson Carbon in the product is increased in relation to that content in the feed. This effect is illustrated in Comparison Example 5 of Table 2. Within the scale of conditions for the process of the present invention, the growth or increase of Conradson Carbon can be totally inhibited and the Conradson Carbon components can be converted with components Conradson's non-carbon. Preferably, the conversion of Conradson Carbon will vary from about 0 to 5%, more preferably, from about 5 to 20%, and more preferably, from 10 to 40%. The following examples illustrate the -invention, but are not intended to be limiting in any way. Two feeding materials were used - in this study (Table 1). One was a mixture of Kome and Bolobo crudes from CHAD. The other was an extra heavy Campo-1-Bare oil from Venezuela. Both were heated to 110 ° C with nitrogen purge to remove water by volume before use.

TABLE 1 Kome / BolojDo Campo-1-Bare TAN (Mg KOH / g of RAW 5.3 3.0 Sulfur,% by weight 0.2 3.7 Conradson Carbon,% by weight 7.6 16.3 Vacuum Residue,% by weight 49 50.5 API Gravity 18 8.7 Viscosity, cSt @ 40SC 1100 28,000 Example # 1: This example was carried out in a 300 cc stirred autoclave reactor. The reactor was operated in a batch mode with respect to the crude that was charged. Hydrogen was flowed through the autoclave to maintain the constant hydrogen partial pressure and to control the pressure of water and carbon dioxide in the reaction zone. The reactor was charged with 100 g of mixture - from Kome / Bolobo and 0.61 g. of MOLYVAN (R) -L * (8.1% • in molar weight), was flooded with hydrogen and then subjected to pressure at 2514.58 kPa with hydrogen at room temperature. The hydrogen flow was then initiated through the autoclave at a rate of 0.1 liter / minute, while maintaining a pressure of 2514.58 kPa) by the use of a counter pressure regulator at the outlet of the reactor. Then the reactor was heated to 329.44aC with stirring and maintained at 329.44eC for 60 minutes at 2514.58 kPa. The calculated partial pressures of hydrogen and water ** were, respectively, 2268.46 kPa and 89.64 kPa. Upon cooling to 121.112C, the reactor was vented and flooded with hydrogen to recover light hydrocarbon products including hydrocarbons that are normally gaseous at room temperature. The reactor oil was then discharged, combined with liquid hydrocarbon removed when the reactor was vented and the mixture was tested for a total acid number (TAN) using ASTM Method M-664, where TAN = mg KOH per gram of crude oil (or product oil). The TAN measured was 0.43. * MOLYVAN (R) -L, supplied by the R. T. Vanderbilt Company, is di (2-ethylhexyl) phosphorodithioate molybdenum. ** A maximum of 1.25 moles of water formed per mole of destroyed acid is assumed.

Example # 2 (Comparative) This example illustrates the degree of conversion of TAN obtained when Kome / Bolobó crude mixture was heated at 329.44aC for one hour in the absence of catalyst and hydrogen. The procedure of Example # 1 was repeated, except that the MOLYVAN (B, -L) was omitted and that the test was carried out with an inert gas sweep at a reactor pressure of 308.18 kPa. reactor was 3.40.

Compendium of Examples with Kome / Bolobo Crude Blend Example # 1 illustrates the destruction of TAN in the Kome / Bolobo crude (Table 2) using a small amount of highly dispersed catalyst under relatively mild conditions and with a partial pressure of water in the lower reactor, at 137.9 kPa, This treatment provides a reduction in TAN substantially greater than that which can be obtained by the heat treatment only in comparable time and temperature (Example # 2).

TABLE 2 EXAMPLE 1 2 Gas Scan Hydrogen Inert Gas (He) Mo, ppm weight 491 0 Temperature, aC 329.44 329.44 / Reactor Pressure, kPa 2413.2 206.85 Hydrogen pressure, calculated kPa 2323.6 0 Water, kPa, Calculated 89.6 < 6 '.9 TAN of Product 0.43 3.40 Example # 3 The feedstock used in this example was dry Campo-1-Bare crude. Mo was supplied as a catalyst precursor concentrate which was prepared in the following manner. A solution of 8 g. of phosphomolytic acid of Fisher reagent grade were dissolved in 92 g of deionized water. Next, 10 g of solution were injected into 90 g of Campo-1-Bare crude oil while stirring at 80 aC in an autoclave - at ¬ of Autoclave Engineer's Magnedrive. After stirring for 10 minutes at 80 aC, the autoclave was flushed with nitrogen and the temperature was increased to 148.89eC - to remove the water. The resulting precursor concentrate contained 0.45% by weight of Mo. The autoclave was charged with 99.43 g. of dry Campo-1-Bare crude and 0.57 g of precursor concentrate to provide a reactor charge containing 25 ppm by weight of Mo. The reactor was flooded with hydrogen and then pressurized to 446.08 kPa with hydrogen sulfide. . During heating with stirring for 10 minutes at 176.67 to 204.44aC, the reactor pressure was increased to 2169.83 kPa with hydrogen and a hydrogen flow of 0.2 liters / minute (380 SCF B) was initiated through the autoclave. The pressure was maintained by the use of a counter pressure regulator in the gas outlet line of the reactor. The temperature was increased to 385aC during a stirred reaction period of 120 minutes. The partial pressure of water in the reactor was calculated to be 37.92 kPa (assumes 1.25 moles of water per mole of acid destroyed). The reactor was vented at atmospheric pressure while it is at 121.IlaC, and the remaining oil in the reactor was filtered at 82.22 to 93.33aC to remove 0.03 g. of residue containing catalyst. The filtered reactor oil was combined with light liquids that were removed from the reactor during the course of the test and subsequent ventilation steps. The combined liquid products, which weighed 96.9 g, had a TAN of 0.10 (mg KOH / g mixture) and contained 15.9% by weight of Conradson Carbon.

Example # 4 The procedures of Example - # 3 were repeated, except that the test was carried out at a pressure of 2859.33 kPa and that the water was fed to the reactor at a rate of 0.033 g / ml. The partial pressure of water in the reactor during the test was approximately 634.34 kPa. 0.05 g was recovered. of residue - which contains catalyst, and 96.4 g. of product liquid mixture that had a TAN of 0.43 and contained 15.4% by weight of Conradson Carbon.

Example # 5 (Comparative) The procedures of Example # 4 were repeated, except that the catalyst was not added and that the experiment was carried out at 2169.83 kPa with argon as the scavenging gas. 97.4 g of product liquid mixture were recovered and had a TAN of 0.63 and contained 17.9% by weight of Conradson Carbon. The partial pressure of water in the reactor was approximately 634.34 kPa.

Example # 6 The procedures were repeated in Example # 3, with the following changes. The reactor was charged with 98.86 g. of crude oil and 1.14 g. of precursor concentrate that provided a reactor charge containing 50 ppm by weight of Mo. The test was carried out at 398.89aC for 2 minutes at 2169.83 kPa with a hydrogen sweep of 0.12 liters / minute (380 SCF / B) . The water was fed to the reactor at a rate of 0.017 g / minute 'to provide a partial pressure of water in the reactor of 379.22 kPa. 0.05 g of catalyst residue and 97.3 g of product liquid mixture were recovered. a TAN of 0.31, and contained 15.2% by weight of Conradson Carbon.

Example # 7 The procedures of Example # 6 were repeated, except that the hydrogen scavenging rate was 0.24 liters / minute (780 SCF / B), which resulted in a partial pressure of water in the reactor of 179.27 kPa, 0 were recovered. , 04 g of catalyst residue and 96.8 g of product liquid mixture having a TAN of 0.12, contained 15.4% by weight of Conradson Carbon and a kinematic viscosity of 918 centistokes at 40 aC.

Compendium of Examples with Field Crude-1-Bare (Table 3) The comparison of Example # 3 with Example # 4 illustrates the effect of water inhibition on the conversion of TAN as well as the comparison of Example # 6 with the Example # 7, where a decrease in partial pressure of water from 379.22 to 179.27 kPa reduced the TAN from 0.31 to 0.12, The comparison of Example # 4 with Example # 5 illustrates that the use of "more hydrogen catalyst, in accordance with the process of this invention provides TAN conversion greater than a particular partial pressure of water that can be obtained by heat treatment in the absence of hydrogen and catalyst, TABLE 3 Example No. 3 4 5 6 7 Sweeping Regimen, SCR / B 380 380 380 380 • 380 Water pressure, kPa 37.94 634.34 634.34 379.22 179.27 Hydrogen pressure kPa 1751.3 1827.18 0 1785.80 1792.7 Liquid Product Mix TAN 0.1 0.43 0.61 0.31 0-, 12 Conradson carbon% by weight 15.9 15.4 (17.9) 15.2 15.4 Vacuum Residues,% Conversion 26.3 21.2 26.8 25.7 25.6 The Conradson Carbon values were determined by the Micro Method, which is ASTM D 4530. This test determines the amount of carbon residue formed after the evaporation and pyrolysis of petroleum materials under specified conditions, the test results are equivalent to those obtained using the Conradson Carbon Residue Test (Test Method D 189).

Claims (7)

1. A method for reducing the amount of carboxylic acids in petroleum feeds comprising the steps of: (a) adding to the petroleum feed a catalytic agent comprising a petroleum-soluble or oil-dispersible compound of a metal selected from the group consisting of Group VB, VIB, V IB and VIII metals, wherein the amount of metal in the petroleum feed is at least about 5 ppm by weight; (b) heating the oil feed with the catalytic agent in a reactor at a temperature of about 204444 to about 426.67a, under a hydrogen pressure of about 204.75 to 6996.33 kPa; and (c) sweep the reactor containing the oil feed and the catalytic agent with hydrogen-containing gas to maintain the partial pressure of water and combined carbon dioxide less than about 344.75 kPa

2. The method according to claim 1, wherein the catalytic agent comprises a catalyst precursor concentrate of a petroleum-soluble or oil-dispersible metal compound prepared in a petroleum feed selected from the group consisting of whole, raw, first distillate crudes. atmospheric residue, vacuum residue, vacuum gas oil, and mixtures thereof

3. The method according to claim 1, wherein the catalytic agent comprises a metal sulphide concentrate of a metal compound soluble in water. oil or dispersible in oil, prepared in a petroleum feed selected from the group consisting of whole crudes , crude of first distillation, atmospheric residue, vacuum residue, vacuum gas oil, and mixtures thereof,

4. - The method of compliance with. claim 3, wherein the metal sulphide concentrate is heated at a temperature and for a time sufficient to form a dispersion of 0.5 to 10 micrometer catalyst particles comprising a metal sulfide component in association with a solid carbonaceous derived from the oil feed in which the metal sulfide is dispersed.

5. The method according to claim 1, wherein the catalytic agent is a dispersion of 0.5 to 10 micrometer catalyst particles comprising a metal sulfide component in association with a carbonaceous solid derived from the feed. of oil.

6. The method of compliance, with claim 1, wherein the metal is selected from the group consisting of molybdenum, tungsten, vanadium, iron, cobalt nickel, chromium and mixtures thereof.

7. The method according to claim 1, wherein the petroleum-soluble or oil-dispersible metal compound is a heteropoly acid of tungsten or molybdenum. § The method according to claim 1, wherein the petroleum-soluble or oil-dispersible metal compound is selected from the group consisting of phosphomolybdic acid, molybdenum naphthenate, and molybdenum dialkylphosphorodithioate. 9. The method of compliance with claim 1, wherein the combined partial pressure of water and carbon oxides is less than about 206.85 kPa. 10. The method according to claim 1, wherein the water is substantially removed from the oil feed before the heating step.