Use of polymers as heterogeneous hydrogen donors in the upgrading of heavy and extra-heavy crudes

Abstract

The present invention is related to the application of solid polymers or copolymers prepared from monomers having in their structure a polycyclic aromatic ring, an aromatic ring of the type of naphthalene, or polyesters, polyethers, polyamides or polyvynil derivatives having naphthalene units in their structure, in the hydrotreatment or hydrocracking of heavy hydrocarbons, such as heavy or extra-heavy crude oils or residues from the distillation of petroleum; these polymers or copolymers may be supported, anchored or in a physical mixture with metallic oxides such as alumina, silica, titania or kaolin, and they have an application as heterogeneous hydrogen donors in reactions of hydrotreatment or hydrocracking of heavy or extra-heavy crude oils, residues from the distillation of petroleum and cuts and streams deived from this distillation. These solid polymers or copolymers operate in the presence of hydrogen or methane-rich gas. These hydrogen donor polymers, being solid, may be recovered from the reaction mixture to be reused and have a thermal stability that allows for their use in reactions at temperatures above 450 C. These heterogeneous hydrogen donors improve the physical properties of crude oils, such as API gravity, viscosity, and distillates yield, inhibiting the formation of coke.

Claims

1. A method for hydrotreatment or hydrocracking of heavy hydrocarbon feedstocks, comprising: hydrogenating a heavy hydrocarbon in the presence of at least one hydrogen donor; wherein the hydrogen donor comprises at least one solid polymer or at least one solid copolymer containing units with two or more fused aromatic, alicyclic, or heterocyclic rings, or any combination thereof.

2. The method of claim 1, wherein the polymer or copolymer has a melting and decomposition temperature above 450 C.

3. The method of claim 1, wherein the polymer or copolymer is chemically stable in reducing atmospheres at temperatures up to 450 C.

4. The method of claim 1, wherein the hydrotreatment or hydrocracking of heavy hydrocarbons is carried out in the presence of a gas rich in hydrogen or methane.

5. The method of claim 1, wherein the hydrotreatment or hydrocracking of heavy hydrocarbons is carried out in a fixed bed, ebullating bed, or slurry reactor, in a continuous or batch operation.

6. The method of claim 1, wherein the polymer or copolymer contains polyaromatic structures, polyester structures, polyether structures, polyamide structures or polyvinyl derivative structures.

7. The method of claim 1, wherein the polymer or copolymer is supported, anchored, or in a physical mixture with solid materials.

8. The method of claim 1, wherein the polymer or copolymer is supported, anchored, or in a physical mixture with metallic oxides.

9. The method of claim 8, wherein the metallic oxides are selected from alumina, silica, titania, and kaolin.

10. The method of claim 1, wherein the polymer or copolymer is used alone or in combination with a catalyst.

11. A method for hydrotreatment or hydrocracking of heavy hydrocarbon feedstocks, comprising: hydrogenating a heavy hydrocarbon in the presence of at least one hydrogen donor; wherein the hydrogen donor comprises at least one solid polymer or at least one solid copolymer containing units with two or more fused aromatic, alicyclic, or heterocyclic rings, or any combination thereof; and wherein the polymer or copolymer has a melting and decomposition temperature above 450 C.

Description

BRIEF DESCRIPTION OF THE DRAWINGS OF THE INVENTION

(1) FIG. 1. Structures of hydrogen donor polymers with a system of polycyclic saturated and unsaturated hydrocarbons and as examples naphthalene 1, tetralin 2 or decalin 3 connected by different functional groups GF, such as esters 1a or ethers 1b.

(2) FIG. 2. Representation of the process cycle of the heterogeneous hydrogen donor polymer with a tetralin unit II that transfers hydrogen to the low-quality crude oil III obtaining a crude oil with improved properties IV and a polymer with a naphthalene unit I which by reaction with hydrogen regenerates the hydrogen donor polymer with a tetralin unit II and starts a new cycle.

(3) FIG. 3. C.sup.13 solid NMR spectra of the hydrogen donor polymer 1a in which the structural changes brought about by the hydrogenation of the naphthalene unit and its conversion to a tetralin unit may be observed as a function of hydrogen pressure.

(4) FIG. 4. Scheme of the process flow diagram for the treatment of heavy crude oil with the heterogeneous hydrogen donor polymer in a continuous flow reactor. Number 1 marks the crude oil feed which is heated in section 2 and number 3 identifies the hydrogen or methane feed to the reactor 4 from where the light fractions and gases are sent to section 6 and the upgraded heavy fractions to section 5. In section 6 the gases 7 are separated from the light fractions 9 which are mixed with the upgraded heavy fractions 10 to generate the upgraded crude oil 8.

(5) FIG. 5. Results of API gravity of upgraded crude oils obtained in a pilot plant with and without a packed bed of heterogeneous hydrogen donor polymer in the reactor, using a 14.66 API crude oil known as Altamira and hydrogen as reducing agent.

(6) FIG. 6. Results of kinematic viscosity cSt of upgraded crude oils obtained in a pilot plant with and without a packed bed of heterogeneous hydrogen donor polymer in the reactor, using a 14.66 API crude oil known as Altamira and hydrogen as reducing agent.

(7) FIG. 7. Results of sediments formation determined by the ASTM-D-4807 method of upgraded crude oils obtained in a pilot plant with and without a packed bed of heterogeneous hydrogen donor polymer in the reactor, using a 14.66 API crude oil known as Altamira and hydrogen as reducing agent.

(8) FIG. 8. Results of increase in the distillates yield with respect to the feedstock determined by gas chromatography with SimDis software of upgraded crude oils obtained in a pilot plant with and without a packed bed of heterogeneous hydrogen donor polymer in the reactor, using a 14.66 API crude oil known as Altamira and hydrogen as reducing agent.

DETAILED DESCRIPTION OF THE INVENTION

(9) This invention refers to an alternative for the upgrading of heavy and extra-heavy crude oils by reducing their viscosity, increasing their API gravity and yield of distillates, while inhibiting coke formation in the hydrotreatment or hydrocracking of heavy hydrocarbons, such as heavy or extra-heavy crude oils or residues from the distillation of petroleum, by means of the application of heterogeneous hydrogen donor polymers (usually naphthenic-aromatic polycyclic hydrocarbons or naphthalene-based compounds that may be reversibly hydrogenated-dehydrogenated in the reaction mixture). The hydroprocessing of heavy crude oils is limited by the availability of hydrogen, which must be transferred to the liquid phase before the hydrogenation reaction can start; usually the availability of hydrogen is increased by increasing the hydrogen partial pressure in the gas phase. Hydrogen donors provide an additional amount of hydrogen for the reaction, via dehydrogenation of the hydrogen donor molecules and transfer of hydrogen atoms to the heavy hydrocarbons, thus improving the quality of the cracking products and inhibiting the polymerization of the heavier hydrocarbons that proceeds through a free radicals mechanism. In this way coke formation is reduced and the yield of light and middle distillates can be increased.

(10) ##STR00003##

(11) R,RO-Aromatic-, COO-Aromatic-, CH.sub.2CH.sub.2

(12) Some properties of the heterogeneous hydrogen donor polymers applied to the upgrading of heavy and extra-heavy crude oils in this invention are: Melting and decomposition temperatures above 450 C. Chemical stability of the polymer structure (functional groups). Possibility of improving textural properties. Possibility of supporting on clay-type materials. Preparation from commercial raw materials. Preparation can be scaled up to industrial production.

(13) It is important to point out that the technologies described in the state of the art present serious drawbacks, in that the recovery and recycle of conventional hydrogen donors is difficult and usually they remain in a mixture with the reaction products or they are separated by means of conventional separation technologies such as distillation, resulting in a loss of yield of products and an additional cost that reduces the value of these alternatives.

(14) Therefore, the present invention refers to the application of heterogeneous hydrogen donor polymers in the hydrotreatment or hydrocracking of heavy hydrocarbons, such as heavy or extra-heavy crude oils or residues from the distillation of petroleum, said polymers being based on polycyclic saturated or unsaturated hydrocarbons, having as a specific example polymers containing naphthalene, anthracene or phenantrene units and more specifically polyester-type polymers containing naphthalene such as the one described in FIG. 1, that present activity as hydrogen donors for unsaturated compounds reduction reactions and for the hydrocracking of high-molecular-weight molecules into lower molecular weight molecules in a fixed-bed, ebullated-bed or slurry reactor in batch or continuous operation that provides a suitable environment for the reduction and hydroprocessing reactions and in which the properties that are required from the hydrogen donor polymers are: melting and decomposition temperatures above 450 C., chemical stability of the polymer structure (functional groups), satisfactory textural properties via supporting or physical mixing on metallic oxides such as alumina, silica, titania or kaolin, preparation from commercial raw materials and possibility of scale-up for industrial production. Furthermore, in the present invention we describe the application of polymers and co-polymers of polycyclic hydrocarbons, such as polyaromatics, and more specifically polymers containing naphthalene, anthracene or phenantrene units, as heterogeneous hydrogen donors in the hydrotreatment or hydrocracking of heavy hydrocarbons, such as heavy or extra-heavy crude oils and residues from the distillation of petroleum, in the presence of hydrogen or a methane-rich gas.

(15) The application of these heterogeneous hydrogen donor polymers enhances the improvement of some physicochemical properties of heavy and extra-heavy crude oils such as viscosity, coking tendency, yield of distillates and API gravity by hydrotreatment, thermal hydrocracking and reduction of unsaturated compounds in the presence of reducing agents such as hydrogen or methane.

(16) The heavy and extra-heavy crude oil feedstocks that may be upgraded by means of the application of heterogeneous hydrogen donor polymers are those in the 7 to 20 API range, and preferably in the 10 to 18 API range, and fractions derived from them having H/C ratios of 0.5 to 1.8, such as heavy gasoils, bottom-of-the-barrel residues and light cycle oils.

(17) FIG. 2 shows how hydrogen donor polymer I, in a reducing atmosphere such as hydrogen, methane, mixtures of these or a gas phase hydrocarbon mixture like natural gas, undergoes the conversion of the naphthalene unit to a tetralin unit II at suitable pressures and temperatures. The tetralin unit performs as a hydrogen donor and in the presence of unsaturated, high-molecular weight compounds typical of heavy and extra-heavy crude oils III transfers hydrogen atoms for reduction, hydrocracking and hydrogenation reactions, promoting the conversion of feedstock III to product IV, which is an upgraded, higher-hydrogen-content crude oil with improved properties such as viscosity, coking tendency, yield of distillates and API gravity.

(18) To this end we present the following examples of heterogeneous hydrogen donor polymers that have melting and decomposition temperatures above 450 C., a chemically stable structure (functional groups), the possibility of improving their textural properties by mixing or supporting on clay-type materials or metallic oxides such as alumina, silica, titania or kaolin, are prepared from commercial raw materials and their synthesis process may be scaled-up. These polymers are polyesters derived from 1,5-dihydroxinaphthalene and from different carboxylic acids. These polymers have been described by Asrar, J.; Toriumi, H.; Watanabe, J.; Krigbaum, W. R.; Ciferri, A. J. Polym. Sci. Polym. Physics Ed., 21, 1119-1131, 1983; by Acierno, D.; La Manita, F. P.; Polizzotti, G.; Ciferri, A.; Krigbaum, W. R.; Kotek, R. J. Polym. Sci. Polym. Physics Ed., 21, 2027-2036, 1983; by Cai R.; Samulski, E. T. Macromolecules, 27, 135-140, 1994; and more recently by Somogyi, A.; Bojkova, N.; Padias, A. B.; Hall, H. K. Jr. Macromolecules, 38, 4067-4071, 2005. In these works different preparation procedures are described and some physical properties are presented. In particular, in our invention the polyester-type hydrogen donor polymers were prepared in two stages: the first stage is the acetylation of 1,5-dihydroxinaphthalene and the second stage is the polimerization of 1,5-diacetoxynaphthalene with different dicarboxylic acids. With the purpose of disclosing some examples of heterogeneous hydrogen donor polymers, we present the polymers prepared with terephthalic acid, diphenic acid, 4,4diphenyldicarboxylic acid and 1,4-naphthalenedicarboxylic acid, which are identified in the examples as polyesters: Pester 1, Pester 2, Pester 3 and Pester 4, respectively.

Example 1

(19) Preparation and Characterization of the Hydrogen Donor Polymer Identified as Pester 1.

(20) 158.8 g of 1,5 diacetoxynaphthalene, 108 g of terephthalic acid and 0.533 g of sodium acetate are mixed in a 1000 mL Parr reactor, the reactor is closed and agitation is started while introducing nitrogen with a flow of 100 cm.sup.3/min. Once we have an inert atmosphere in the reactor the temperature is increased to 275-300 C. and the reactor is kept at this temperature for 2 hours. During this time the acetic acid generated inside the reactor is removed with a nitrogen flow and the molten reacting mixture starts to become solid. After this time the temperature is increased to 300-345 C. and kept at this temperature for 1-5 hours. Then, the temperature is increased to 350-395 C. and the pressure inside the reactor is reduced to 0.2-5 mm Hg, and these conditions are maintained for 2 to 5 hours. Finally, the reactor is allowed to cool to room temperature without agitation keeping a nitrogen atmosphere. The polymer obtained is washed with 200 mL of acetone, then with 200 mL of chloroform, with 200 mL of toluene and finally with 200 mL of acetone. The washed polymer is dried at 100 C. for 1 h in a vacuum oven. Yield: 149.3 g of the hydrogen donor polymer identified as Pester 1.

(21) The hydrogen donor polymers identified as Pester 2, Pester 3 and Pester 4 are prepared in a similar manner. The following diagram shows these polyesters. Table 1 shows the values of melting points in C. determined by differential scanning calorimetry.

(22) ##STR00004##

(23) TABLE-US-00002 TABLE 1 Characteristics of polyester-type hydrogen donor polymers Polymer M.p. C. Pester 1 443 Pester 2 487 Pester 3 480 Pester 4 481

(24) The polyester-type polymers with naphthalene units in their structure derived from 1,5-diacetoxynaphthalene and from different aromatic dicarboxylic acids that exemplify the heterogeneous hydrogen donor polymers used in the upgrading of heavy and extra-heavy crude oils object of the present invention can be supported in clay-type materials or metal oxides which can be alumina, silica, titania or kaolin, in order to obtain a material with a higher surface area that may be extruded in suitable forms to improve contact between the feedstock, the hydrogen donor and the reducing gas such as hydrogen or methane. Example 2 describes the preparation of a polyester supported on alumina or kaolin.

Example 2

(25) Preparation and Characterization of the Polyester-Type Hydrogen Donor Polymer Identified as Pester 1 Supported on Alumina or Kaolin

(26) (a) Alumina Support.

(27) 70 g of boehmite and 44.2 mL of doubly-distilled water are thoroughly mixed. 20.2 mL of a 1 M formic acid solution are added and mixed to form a smooth paste. Then 21.6 g of the polymer identified as Pester 1 ground to a particle size less than 100 micrometers and water in the amount required for the preparation of a paste suitable for extrusion. The paste is introduced into a stainless steel extruder with a nozzle 2 mm in diameter and the extrusion is carried out. The extrudates are dried at 100 C. in a static air atmosphere throughout the night and then calcined in a nitrogen atmosphere at 500 C. for 2 hours. The yield is 70%.

(28) (b) Kaolin-Silica Support.

(29) 33.9 g of kaolin and 20.7 mL of water are mixed. 14.5 g of Pester 1 polymer ground to a particle size less than 100 micrometers, 20.8 g of colloidal silica and 0.1 mL of formic acid are added and mixed to form a smooth paste. The extrudates are prepared, dried and calcined in the same way described above. The yield is 86%.

(30) TABLE-US-00003 TABLE 2 Surface area of extruded polyester-type polymer identified as Pester 1 Material BET surface area m.sup.2/g Polymer Pester 1 on alumina 300.56 Polymer Pester 1 on kaolin-silica 135.23

(31) The polyester-type polymer identified as Pester 1 is in a dynamic hydrogenation equilibrium in the reaction mixture as shown in FIG. 2. In the following paragraphs the process of reduction of the naphthalene unit in the polymer to a tetralin unit is described and the physical and chemical changes during the hydrogenation-dehydrogenation cycle are discussed. Example 3 shows the evaluation of the process of hydrogenation of polymers with naphthalene units. In particular the chemical and physical stability of the polymer identified as Pester 1 during the hydrogenation cycle is verified in the presence and absence of solvent.

Example 3

(32) Thermal Hydrotreatment of the Polymer Identified as Pester 1 to Measure the Hydrogen Donating Capacity.

(33) The evaluations were performed in a 300 mL Parr autoclave-type reactor. The reactor is of the Robinson-Mahoney type, checked to be leakage-free at a pressure of 100 atm, and the heterogeneous hydrogen donor polymer to be tested is placed in the internal basket.

(34) In a first stage the polymer is purified under an atmosphere of nitrogen at 19 atm by heating to 430 C. for 2 hours. The yield of polymer after this purification step is 87 weight %.

(35) The hydrogenation tests of the heterogeneous hydrogen donor polymer were carried out in the following way: 2.5 g of previously purified polymer are placed into the basket and the weight of the reactor and sample is recorded. The reactor is purged with a nitrogen gas stream at a pressure of 20 lb/in.sup.2 for one minute. Afterwards, the reactor is purged and pressurized with hydrogen and the weight is recorded again. Finally the devices for heating, cooling and agitation (750 rpm) are placed into the reactor.

(36) The test starts by heating the reactor to the required temperature and maintaining it during the hydrogenation time programmed. Once the reaction time is completed, the agitation is suspended, the heating resistance is quickly withdrawn and the reactor is cooled in a bath of water and ice. When the reactor reaches room temperature the cooling hoses are disconnected and the reactor is drained, dried and weighed. Then the reactor is opened, the gas is withdrawn and its weight is recorded to quantify the amount of gas formed in the test. Finally the reactor is opened to recover and quantify the hydrogenated polymer.

(37) The experiments were conducted at 400-450 C., typically at 415-435 C., for 10-18 hours at different pressures, in order to evaluate the degree of reduction of the naphthalene and generation of the hydrogenated ring with hydrogen donor capacity. The values of pressure in the experiments were 5, 10, 20, 30, 40 and 80 atm.

(38) The heterogeneous hydrogen donor identified as Pester 1 subjected to the hydrogenation tests at different pressures, after washing and drying, was submitted to solid state C.sup.13 NMR to monitor the structural changes in the molecule of the polyester-type polymer, and in particular to register the conversion of the naphthalene ring to hydrogenated rings with hydrogen donating capacity. In the NMR spectrum, the set of signals corresponding to the aromatic naphthalene ring unit is in the range of 150-100 ppm and the set of signals corresponding to the saturated unit is in the range of 40-15 ppm, as shown in FIG. 3.

(39) In this Figure we can observe that as the pressure of the hydrogenation process increases, the naphthalene unit in the polymer is gradually hydrogenated to the corresponding structure with hydrogen donating capacity, and that in the polymer obtained in the range of 10 to 80 atm the naphthalene ring has been successfully hydrogenated and can perform as a hydrogen donor.

(40) The physical aspect of the hydrogen donor polymer identified as Pester 1 before the process of hydrogenation is an amorphous solid, dark gray to black, dense and with high hardness, whereas the appearance of the polymer after hydrogenation is an amorphous solid, shiny black, light and brittle.

(41) In the previous section the results that support the viability of the hydrogenation of the polymers with naphthalene units and in particular of the polymer identified as Pester 1 at a temperature of 415-450 C. were presented. In the following examples we show the evidences of the hydrogen donor capacity of these polymers and their ability to maintain this capacity for extended periods of time, in a cyclical process of reduction with hydrogen gas and donation of hydrogen for the hydrotreatment and cracking reactions of high-molecular-weight compounds as shown in FIG. 2, more specifically in the evaluation of these polymers as heterogeneous hydrogen donors in the upgrading of heavy and extra-heavy crude oils.

(42) In the following examples the reference or blank test was the thermal hydrotreatment of a sample of heavy crude oil without using a heterogeneous hydrogen donor polymer.

Example 4

(43) Thermal Hydrotreatment of Crude Oil Without Polymer

(44) The crude oil used for hydrotreatment was a 12 API Mexican crude from the Ku Maloob Zaap fields, known as Ku crude oil, with the physicochemical properties shown in Table 3:

(45) TABLE-US-00004 TABLE 3 Properties of the 12 API crude oil from Ku Maloob Zaap Specific gravity 20/4 C. 0.986 Total sulphur, wt % 5.17 Total nitrogen, ppm 4824 Basic nitrogen, ppm 1155 Nickel, ppm 85 Vanadium, ppm 444 Salt content, ptb 2 nC7 insolubles, wt % 19 Kinematic viscosity at 60 C., cst 1639 Water by distillation, vol % 0.05

Example 5

(46) Thermal Hydrotreatment of the 12 API Ku Crude Oil in a Pilot Plant, in a Continuous Flow Reactor (FIG. 4) Packed With the Heterogeneous Hydrogen Donor Polymer Pester 1.

(47) In the reaction system shown in FIG. 4 and described in the figure captions, the reactor was loaded with 500 mL of the heterogeneous hydrogen donor polymer Pester 1, having a density of 0.82 g/mL; the hermeticity of the system was tested with nitrogen and the flow was adjusted to 80-250 SLPH, maintaining a pressure of 0.5 to 4 kg/cm.sup.2 inside the reactor. The reactor was heated with nitrogen at a rate of 3-35 C./min until reaching 120 C. and the temperature was maintained at 120 C. for 2-4 hours. The temperature in the reactor was raised to 400-490 C. and maintained at 450 C. for 2-6 hours, the flow of nitrogen was replaced with industrial-grade hydrogen and the operating pressure was adjusted to 30-75 kg/cm.sup.2. 200 SLPH of hydrogen were fed to the reactor by the crude oil-hydrogen feed line and 100 SLPH were fed by the gas heater line. The feed vessel and crude oil pump suction and discharge lines were heated. The temperature in the reactor wall was stabilized at 400 C., with the feed flow adjusted at 1000 mL/h. The bottoms product was recovered from the separator and the light product from the condensate tank. During the test the gas product was analyzed by chromatography every 8 hours, determining H.sub.2S, H.sub.2 and C.sub.1 to C.sub.6 paraffins and olefins. At the end of the last balance, the reactor temperature was lowered to 200 C. at a rate of 40 C./min, maintaining the flow of crude oil. After reaching 200 C. in the reactor the flow of crude oil was stopped.

Example 6

(48) Thermal Hydrotreatment of the 12 API Ku Crude Oil With the Heterogeneous Hydrogen Donor Polymer Pester 1 Extruded with Silica-Kaolin

(49) The pilot plant continuous flow reactor (FIG. 4) was loaded with 500 mL of the heterogeneous hydrogen donor polymer Pester 1 extruded with silica-kaolin, having a density of 0.82 g/mL; the hermeticity of the system was tested with nitrogen and the flow was adjusted to 80-250 SLPH, maintaining a pressure of 0.5 to 4 kg/cm.sup.2 inside the reactor. The reactor was heated with nitrogen at a rate of 3-35 C./min until reaching 120 C. and the temperature was maintained at 120 C. for 2-4 hours. The temperature in the reactor was raised to 400-490 C. and maintained at 450 C. for 2-6 hours, the flow of nitrogen was replaced with industrial-grade hydrogen and the operating pressure was adjusted to 30-75 kg/cm.sup.2. 200 SLPH of hydrogen were fed to the reactor by the crude oil-hydrogen feed line and 100 SLPH were fed by the gas heater line. The feed vessel and crude oil pump suction and discharge lines were heated. The temperature in the reactor wall was stabilized at 400 C., with the feed flow adjusted at 1000 mL/h. The bottoms product was recovered from the separator and the light product from the condensate tank. During the test the gas product was analyzed by chromatography every 8 hours, determining H.sub.2S, H.sub.2 and C.sub.1 to C.sub.6 paraffins and olefins.

Example 7

(50) In the Following Examples, We Highlight the Hydrogen Donor Capabilities of the Heterogeneous Hydrogen Donor Polymer Pester 1 Extruded With Kaolin-Silica in the Upgrading of a 14.66 API Heavy Crude Oil Known as Altamira.

(51) The evaluation was carried out in the reaction system shown in FIG. 4, using the conditions and the procedures described in Example 6.

(52) TABLE-US-00005 TABLE 4 Properties of Altamira crude (14.6 API) METHOD GENERAL PROPERTIES API GRAVITY ASTM-D-287 14.66 SPECIFIC GRAVITY 20/4 C. ASTM-D-1298 0.9552 TOTAL SULPHUR, WT % ASTM-D-4294 5.422 SPECIFIC PROPERTIES WATER AND SEDIMENTS, VOL % ASTM-D-4007 0.05 WATER BY DISTILLATION, VOL % ASTM-D-4006 SEDIMENTS BY EXTRACTION, ASTM-D-473 0.03 WT % nC5 INSOLUBLES, WT % ASTM-D-4055 17.08 nC7 INSOLUBLES, WT % ASTM-D-3279 10.68 RAMSBOTTOM CARBON, WT % ASTM-D-524 13.05 CONRADSON CARBON, WT % ASTM-D-189 13.48 POUR POINT, C. ASTM-D-97 21 TOTAL NITROGEN, PPM ASTM-D-4629 2756 BASIC NITROGEN, PPM UOP-313 438 SIMULATED DISTILLATION, C. ASTM-D-7169 IBP 31.8 10 VOL % 184.6 20 VOL % 293.8 30 VOL % 372.4 40 VOL % 442 50 VOL % 519.4 FBP 537.6 VISCOSITY, mm2/s @ ASTM-D-445 15.6 C. 4146.81 25 C. 1947.07 37.8 C. 777.57 54.4 C. 228.13 60 C. 188.07 METALS, PPM ASTM-D-5863 NICKEL 67.48 VANADIUM 238.14

(53) An analysis of the results shown in FIGS. 5, 6, 7 and 8, obtained in a test carried out at different temperatures in a pilot plant using Altamira crude oil as feedstock, the heterogeneous hydrogen donor polymer Pester 1 and hydrogen as a reducing agent, shows clearly the effect of heterogeneous hydrogen donors in the upgrading of heavy crude oils. At 445 C. an increase of 4 units in the API gravity, a lowering of the viscosity at 60 C. from 188 to 25 cSt and an increase in the yield of distillates of 13 vol. % were achieved, with a low (0.045 wt %) sediments content.