RU2383581C2 - Method of processing hydrocarbons obtained using fischer-tropsch method - Google Patents

Abstract

FIELD: chemistry. ^ SUBSTANCE: method of processing hydrocarbon paraffins involves hydrothermal processing metal-oxygenate components contained in hydrocarbons obtained using Fischer-Tropsch method at temperature above 100C, where hydrothermal processing is carried out with water at temperature ranging from 100C to 400C, and hydrothermal processing is carried out after passing the first filtration zone at pressure 0.1-10 MPa for 1-60 minutes, where water is added in order to carry out hydrothermal processing, as well as a method of processing hydrocarbon paraffins, which involves chemical processing metal-oxygenate components contained in the hydrocarbon paraffins obtained using the Fischer-Tropsch method with one or more chemical processing reagents selected from organic acids and anhydrides, carried out in a single liquid phase in order to modify metal oxygenates. ^ EFFECT: use of given methods prevents clogging of catalyst layers with metal-containing particles. ^ 20 cl, 13 tbl, 1 dwg

Description

Technical field

The invention relates to hydrothermal treatment of hydrocarbons before further processing. In particular, the invention provides a pretreatment mode for hydrocarbons produced by the Fischer-Tropsch process (FT) before further processing. The invention also relates to the chemical treatment of hydrocarbons before further processing.

Justification of the invention

The inventors have identified an area for optimizing a hydrocarbon processing method. In particular, the inventors have determined in the general case the field of optimization of the method for processing FT synthesis products using hydroconversion.

Product streams obtained by FT method contain oxygen-containing products (oxygenates, oxygenate) and, to some extent, metals and / or metal-containing particles. The main components of the fraction containing oxygenates are ketones, aldehydes, alcohols, esters and carboxylic acids. Under certain conditions, carboxylic acids and alcohols are capable of forming carboxylate and / or alkoxide complexes and / or metaloxanes with the metals and / or metal-containing particles present. These metal carboxylates and / or alkoxides and / or metaloxanes can settle on process equipment and catalyst beds. Ultimately, the mass of precipitation on the catalytic layers can reach a value that makes reactor shutdown inevitable.

The described problem can be defined as clogging of the catalytic layer (catalytic layers) of the equipment for subsequent processing by a certain component of these product streams or by the reaction product of a component of these product streams.

SUMMARY OF THE INVENTION

Without resorting to any theory, the inventors believe that clogging is caused by organometallic material and / or small particles. It is likely that the organometallic material and / or small particles are enriched in aluminum and / or silicon and / or titanium and / or zirconium and / or cobalt and / or iron and / or alkaline earth elements such as calcium, barium, etc. d.

The composition of the Fischer-Tropsch synthesis products was analyzed, and it was found that the condensate fraction contains virtually no metal-containing impurities (1 part per million or less), while paraffin contains about 10-100 parts per million metal-containing impurities. This indicates that the FT method itself and / or the filtration system and / or refractory materials and / or metals or metal-containing particles chemically leached during processing can serve as a source of metal-containing impurities.

There are two possible types of metal oxygenates that contribute to clogging of the catalytic layers, and each of these types or both of them can be important:

a) Small particles: for example, small particles with a diameter of less than 1 micron, which can be stabilized by surface-active compounds (such as oxygenates), which allows them to remain in suspension. However, when the specified surface layer is destroyed, the particles settle and form sediments in the collector areas.

b) Organometallic compounds: for example, if aluminum acts as a metal source, it is possible to form organoaluminum compounds of the AI-O-R type, such as alkoxyaluminium, aluminum carboxylates and aluminoxanes, or compounds of the AI-R type, such as aluminum alkyl, or combinations thereof.

Clogging of the catalytic layer was observed in various catalysts; the clogging may take the form of a localized accumulation or dispersed powdery substance.

There is a hypothesis that the FT synthesis product stream transfers small concentrations of organometallic material and / or small solubilized catalyst particles and / or filter aid and / or refractory material and / or metals or metal-containing particles chemically leached from the reactor system. Paraffin contains oxygenates, such as acids and alcohols, which allow you to maintain small particles in the paraffin in a solubilized state.

It is believed that during hydroconversion, said oxygenates, which help to keep particles in suspension and / or ligands of organometallic components, undergo hydrogenation and / or protonation, as a result of which the modified metal-containing particles are then deposited in the catalytic bed of the hydroconversion reactor, causing a phenomenon called “bed clogging” .

Thus, after conducting research and experiments, the inventors proposed the following solution, which can at least partially solve the problem described above.

In accordance with a first aspect of the present invention, there is provided a method for treating hydrocarbons, comprising hydrothermally treating metal-oxygenate components contained in hydrocarbons produced by the Fischer-Tropsch process at temperatures above 100 ° C, where the hydrothermal treatment is carried out with water at temperatures from 100 ° C to 400 ° C, and hydrothermal treatment is carried out after passing through the first filtration zone at a pressure of 0.1-10 MPa for 1-60 minutes, and in order to carry out hydrothermal treatment, I add water.

The method may further include chemically treating the metal oxygenate components contained in the hydrocarbons obtained by FT method with organic acids and / or anhydrides to modify metal oxygenates.

The specified method may include one or more of the following processing operations:

(i) filtering the modified metal oxygenates at the end of a period of time sufficient for the growth of particles and / or their adsorption on filterable particles;

(ii) adsorption of the modified metal oxygenate on the adsorbent.

The hydrocarbons obtained by FT method contain oxygenates and, to some extent, metals and / or metal-containing particles. The main components of the fraction containing oxygenates are ketones, aldehydes, alcohols, esters and carboxylic acids. Under certain conditions, carboxylic acids are capable of forming metal-carboxylate complexes with metal-containing particles present in the system. Under certain conditions, alcohols can form metal-alkoxide complexes with metal-containing particles present in the system.

The metal oxygenate may be a metal carboxylate, a metal alkoxide, or a combination of these components.

Hydrothermal treatment can be carried out at a temperature of from 120 ° C to 370 ° C, usually at a temperature of from 160 ° C to 250 ° C, and a pressure of preferably from 0.5 to 5 MPa (5 to 50 bar), preferably for 1 up to 30 minutes, and more preferably 5 to 10 minutes.

The water used in the hydrothermal treatment may be a combination of reaction water already present in the hydrocarbons obtained by the Fischer-Tropsch process and water added to carry out the hydrothermal treatment.

Hydrothermal treatment can be carried out essentially in a system consisting of a single liquid phase in which both hydrocarbons and water are present, and water is present in an amount sufficient to form essentially one liquid phase under the conditions of the process.

Hydrothermal treatment can be carried out in the presence of an adsorbent, such as silica. Modified metal oxygenates are adsorbed onto the silica particles, and then these particles can be recovered by filtration.

A possible chemical treatment may include transesterification to exchange longer hydrocarbon chains of carboxylic acids or alcohols into shorter chains of carboxylic acids.

Chemical reagents that can be used in transesterification or ligand replacement operations are selected from the group consisting of oxalic acid, acetic acid, propionic acid, salicylic acid, succinic acid, tartaric acid, lactic acid, malonic acid, glycic acid, citric acid, maleic acid, fumaric acid, phthalic acid and the anhydrides of these acids.

Hydrothermal treatment can lead to hydroxylation and the formation of one or more metal hydroxides and / or metal oxyhydroxides. Hydrothermal treatment can be carried out before, during or after a possible chemical treatment.

In accordance with a second aspect of the present invention, there is provided a method for treating hydrocarbons, comprising chemically treating metal-oxygenate components contained in hydrocarbon paraffins obtained by the Fischer-Tropsch process with one or more chemical processing reagents selected from organic acids and anhydrides carried out in a single liquid phase to modify metal oxygenates.

The specified chemical treatment may be followed by one or more of the following processing operations:

(i) filtering the modified metal oxygenates with a filter material at the end of a period of time sufficient for the growth of particles and / or their adsorption on filterable particles;

(ii) adsorption of the modified metal oxygenate on the adsorbent.

Chemical treatment may include transesterification carried out to exchange longer hydrocarbon chains of carboxylic acids or alcohols for shorter chains of carboxylic acids.

The reagents used for chemical processing, which can be used in the operations of transesterification or substitution of ligands, are selected from the group consisting of oxalic acid, acetic acid, propionic acid, salicylic acid, succinic acid, tartaric acid, lactic acid, malonic acid, glycinic acid, citric acid, maleic acid, fumaric acid, phthalic acid and the anhydrides of these acids. The interaction between these chemicals and metal oxygenates can be accelerated by heat treatment.

Chemical treatment can be carried out in a system consisting of a single liquid phase, in which both hydrocarbon paraffins and one or more chemicals for chemical treatment are present, and the concentration of the chemical reagent (s) present is less than the concentration of its saturated solution in hydrocarbons, for example paraffin.

The amounts of chemical treatment reagents added during the chemical treatment may be such as to ensure the formation of a single liquid phase, i.e. for the complete dissolution of reagents for chemical treatment in hydrocarbons in the conditions of the method.

One or more than one substance from the range of adsorbents, filter material and filterable particles is selected from the group comprising at least clays, silica, aluminosilicates, silicon-containing aluminas, cellulose, activated carbons, sintered metals, titanium oxide and cloth filters such as nylons and polycarbonates. Adsorbents can also be used as filter materials.

Adsorbents can be added during chemical treatment.

The growth of filterable particles is influenced by the conditions of the thermal and / or hydrothermal treatment; possibly, depending on the acid used as a reagent for chemical treatment, as well as on the conditions of the method, reversible or irreversible particle growth can be achieved, which, in turn, affects the extraction of modified metal-containing particles by filtration.

Examples of the application of the method proposed in accordance with the present invention

When analyzing reactor paraffin coming from a Fischer-Tropsch low-temperature plant (NTFT), it was found that it contains metal carboxylates (M _x [O ₂ CR] _y ), carboxy-substituted metaloxanes ([M (O) _x (OH) _y (O ₂ CR) _z ] _n ), alkoxides and combinations thereof, leached from the catalyst and / or the carrier and / or reactor and / or filtering clays and / or refractory materials.

The longer the hydrocarbon chain (-CR) of the carboxylate or alkoxide ligand attached to the metal, the better this component dissolves in paraffin.

It is believed that when carboxylic acids or anhydrides with a shorter carbon chain and / or water are added to paraffin in the presence of water, long-chain oxygenates associated with metal-containing particles and / or powdered substances are replaced by shorter-chain carboxylic acids and / or hydroxides by reaction transesterification and / or substitution of the ligand and / or hydroxylation:

- the modification of metal oxygenates obtained by the reaction of exchanging carboxylic acids with a longer carbon chain for shorter chain carboxylic acids or by hydroxylation under the action of water results in modified metal oxygenates that are more soluble in polar solvents such as water or ethylene glycol, and can be extracted from paraffin with these polar solvents;

- modification of metal oxygenates obtained by the reaction of exchanging carboxylic acids with a longer carbon chain for shorter chain carboxylic acids or by hydroxylation under the action of water, leads to the growth of particles, which can then be filtered;

- modification of metal oxygenates obtained by the reaction of exchanging carboxylic acids with a longer carbon chain for shorter chain carboxylic acids or by the hydroxylation reaction under the influence of water leads to the formation of particles that can be extracted / adsorbed on an adsorbent.

experimental part

A) Demonstration of the extraction of metal particles from paraffin using hydrothermal treatment

The experimental setup used for research is shown in the drawing. It is a continuous apparatus with a downward flow. Perhaps the application of pressure.

Water is pumped through a hot tube at a temperature of 140 ° C from a tank placed on the balance using an HPLC pump. Water (2 wt.% With respect to paraffin) is fed into molten paraffin heated to 140 ° C. The combined streams then seep through a layer of sand heated to a temperature of 350 ° C. An inert material is used to better distribute or mix the aqueous and paraffin phase and to increase the residence time in the apparatus, which allows particles of modified aluminum oxygenate to grow and improves the efficiency of the separation process. To collect agglomerates of modified aluminum oxygenate, the product passed through a layer of sand is passed through a filter with a pore size of 1 micron (or less). The aluminum content in the paraffin obtained after filtration is ≤1 ppm Al, which is determined using ICP (induction-coupled plasma). It is possible to use filters with a pore size of more than 1 micron in combination with filter aid.

C) Examples showing the extraction of metal particles from paraffin by chemical treatment followed by filtration

B.1 - Citric acid as a chemical treatment reagent

For experiments CH1, CH3 and CH5, 250 g of paraffin obtained by FT method and containing oxidized aluminum-containing particles (carboxylates and / or alkoxides) were loaded into a 600 ml autoclave. Paraffin was first heated to the treatment temperature, and then citric acid (time zero) was added to the autoclave and stirring was started. Samples of paraffin were taken as time passed, without stopping the installation, and passed them through a filter with a pore size of 0.85 microns. The filtered paraffin samples were then analyzed for aluminum content using ICP (the results are summarized in Table B1).

Table B1 No. exp wt.% citric acid Temperature ° C Ppm Al in paraffin after x minutes of mixing X = 0 X = 5 X = 10 X = 15 CH1 0.1 165 fifty one CH3 0.05 165 fifty 39 13 one CH5 0.02 165 fifty 43 8

B.2.1 - Maleic anhydride as a chemical treatment reagent for hydrothermal treatment at various water contents

For experiments B2 (a-c), paraffin (200 g) containing 50 parts per million aluminum, which is in the form of aluminum oxygenates, was first melted in a furnace at a temperature of 140 ° C, and then it was placed in a Parr autoclave and heated with stirring (700 rpm) / min) up to 230 ° С. Maleic anhydride (0.1 wt.% With respect to the loaded paraffin) was dissolved in water (4 g in experiment B2 (a), 6 g in experiment B2 (b) and 16 g in experiment B2 (c)) and placed in a metal tube, which was then connected to the Parr reactor. After reaching the desired temperature, the pressure in the vessel was raised through a metal tube to 1 MPa (10 bar). This ensured that the entire aqueous solution entered the Parra autoclave. The first sample was taken 5 minutes after the indicated addition. Samples were also taken after 10 minutes. After taking paraffin samples, the sample bottle was placed in an oven heated to 140 ° C. This paraffin was then filtered hot (140 ° C.) through 0.45 micron filter paper. Then the aluminum content in paraffin was analyzed using ICP. As can be seen from Table B2A, the addition of water (hydrothermal treatment) accelerates particle growth and, therefore, improves the ability to separate modified aluminum oxygenates from paraffin by filtration.

Table B2A No. exp wt.% maleic anhydride wt.% water Al (parts per million) after 5 min Al (ppm) after 10 min B2 (a) 0.1 2 5 one B2 (b) 0.1 3 2 B2 (c) 0.1 8 <1 <1

B.2.2 - Treatment with different concentrations of maleic anhydride and at different temperatures of hydrothermal treatment

For experiments B2 (gf), first paraffin (200 g) containing 45 parts per million aluminum was melted in a furnace at a temperature of 140 ° C, then it was placed in a Parr autoclave and heated with stirring (700 rpm) to 230 ° C in experiments B2 (gf) or 170 ° C in experiment B2 (g). Maleic anhydride (the added amount in wt.% Is indicated in Table B2B) was dissolved in 4 g of water and placed in a metal tube, which was then connected to the Parr reactor. After reaching the desired temperature, the pressure in the vessel was raised through a metal tube to 211 kg / cm ² (300 lb / in ² ). This ensured that the entire aqueous solution entered the Parra autoclave. The first sample was taken 5 minutes after the indicated addition. Samples were also taken after 10 minutes. After taking paraffin samples, the sample bottle was placed in an oven heated to 140 ° C. This paraffin was then filtered hot (140 ° C.) through 0.8 micron filter paper. Then the aluminum content in paraffin was analyzed using ICP. As can be seen from the results shown in Table B2B, maleic acid concentrations up to 0.01 wt.% At 230 ° C are sufficient to accelerate particle growth and, therefore, to improve the separation of modified aluminum oxygenates from paraffin by filtration, but at 170 ° C for sufficient growth takes more time. Since these temperatures lie above the decomposition temperature of maleic acid, it is assumed that the active chemical reagent in this case is the decomposition product of maleic acid, i.e. fumaric acid.

Table B2B No. exp wt.% maleic anhydride Temperature Al (parts per million) after 5 min Al (ppm) after 10 min B2 (g) 0.1 230 ° C one one B2 (d) 0.05 230 ° C one one B2 (e) 0.01 230 ° C one one B2 (W) 0.1 170 ° C 16 one

B.3 - Polyacrylic acid (PAA)

First, paraffin (200 g) containing 50 ppm aluminum was melted in an oven at a temperature of 140 ° C, and then it was placed in a Parr autoclave and heated with stirring (700 rpm) to 165 ° C. To 2 wt.% Water was added 0.1 wt.%. PAA and placed in a metal tube, which was then connected to the Parr reactor. After reaching the desired temperature, the pressure in the vessel was raised through a metal tube to 1 MPa (10 bar). This ensured that the entire aqueous solution entered the Parra autoclave. The first sample was taken 5 minutes after the indicated addition. Samples were also taken after 10 minutes. After taking paraffin samples, the sample bottle was placed in an oven heated to 140 ° C. This paraffin was then filtered hot (140 ° C) through filter paper with a pore size of 0.45 μm. Then the aluminum content in paraffin was analyzed using ICP. As can be seen from the results, PAA is effective in the extraction of modified aluminum oxygenates at 165 ° C.

Table B3 wt.% PAK wt.% water Al (parts per million) after 5 min Al (ppm) after 10 min 0.1 2 <1 <1

B.4: Application of hydrothermal conditions and filterable particles / adsorbent for the modification and adsorption of modified aluminum oxygenates

First, paraffin (200 g) containing soluble metal oxygenates was melted in a furnace at a temperature of 140 ° C. 0.1-0.01 wt.% Aerosil 380 (Degussa) was added to the molten paraffin. Then the molten paraffin was heated with stirring (200 rpm) to 170 ° C. Water (4 ml) was placed in a metal tube, which was connected to the Parr reactor. After reaching the desired temperature, a sample was taken. Then water was added to the reaction mixture, and after 5 and 10 minutes samples were taken (Table B4) and passed through a filter with a pore size of 2.5 microns. Water modified the metal complex so that it could be adsorbed on a particle that could be filtered.

Table B4 Parts per million Al in the initial paraffin wt.% added silica Time min Al (parts per million) % recovered Al 45 0.1 5 one 98 10 <1 > 98 27 0.05 5 3 91 10 <1 > 98 66 0.01 5 25 62 10 22 67

B.5: Effect of used acid on the stability of the grown particles

For experiments B5 (a-d), paraffin (250 g) containing soluble metal complexes was first melted in a furnace at a temperature of 165 ° C. 0.1 wt.% Citric acid was added to the molten paraffin. After reaching the desired temperature, after 5 minutes, a sample was taken, which was processed as described in Table B5.

In experiment B5 (e), paraffin (200 g) containing 45 parts per million aluminum was first melted in an oven at a temperature of 140 ° C, then it was placed in a Parr autoclave and heated with stirring (700 rpm) to 170 ° C. Maleic anhydride (0.1 wt.%) Was dissolved in water (2 wt.%) And placed in a metal tube, which was then connected to the Parr reactor. After reaching the desired temperature, the pressure in the vessel was raised through a metal tube to 211 kg / cm ² (300 lb / in ² ). This ensured that the entire aqueous solution entered the Parra autoclave. 15 minutes after the indicated addition, two samples were taken. After taking paraffin samples, one of the samples was placed in an oven heated to 140 ° C. This paraffin was then filtered hot (140 ° C.) through 0.8 micron filter paper. Sample 2 was first cooled and then reheated to 140 ° C and filtered. The aluminum content in paraffin was analyzed using ICP. Unlike paraffin treated with citric acid, the filterability of paraffin treated with maleic acid remained the same, while the filterability of paraffin treated with citric acid was determined by the reaction conditions.

Table B5B Experiment B5 (e) wt.% maleic anhydride Temperature Sample 1 (parts per million Al) Sample 2 (parts per million Al) 0.1 170 ° C <1 <1

C.1: Adsorption of modified metal oxygenate on an adsorbent

In these experiments, contaminated paraffin was pumped at a certain temperature through a 10 mm diameter tube containing adsorbent or filter material. The indicated pressure was determined by the flow rate of paraffin and the characteristics of the adsorbent. In experiment C1, contaminated paraffin containing 14 ppm aluminum and other metals such as cobalt was pumped through Arbocel BVB40 pulp, used as a filter / adsorbent, in the absence of water and without acid addition (see Table C1). Extraction of aluminum was not observed.

In experiment C2, experiment C1 was repeated, but 2 wt.% Water was added to paraffin (see Table C2). The addition of water led to a complete recovery with continuous filtration for 2.5 hours.

In experiment C3, experiment C2 was repeated, but Vitacel L00 was used as the filter / adsorbent material.

In experiment C4, experiment C2 was repeated, but Celpure S1000 was used as the filter / adsorbent material.

In experiment C5, experiment C2 was repeated, but Degussa silica dried (Aerosil 380) was used as a spray-dried filter material / adsorbent.

In experiments C6 (a-k), a mixture of paraffin and water was pumped through the nozzle layer for a residence time of 19 minutes, and then the mixture was passed through Filtracel 9001 filter material. In experiments C6 (a-e), only water was added. This addition was carried out at various temperatures. In experiments C6 (e-k), a 0.1 M solution of maleic acid in water was also added to paraffin at various temperatures.

No. sample Temperature ° C Pressure drop across the filter, MPa (bar) The addition of water, wt.% Filter / adsorbent Stay time before filtering Al, ppm D65 230 1.2 (12) 2 Filtracel EFC 9001 19 2 D66 230 2.1 (21) 2 Filtracel EFC 9001 19 2 D67 230 2.5 (25) 2 Filtracel EFC 9001 19 one D68 200 3.0 (30) 2 Filtracel EFC 9001 19 <1 D69 200 3.2 (32) 2 Filtracel EFC 9001 19 one D70 200 3.6 (36) 2 + 0.1 M maleic acid Filtracel EFC 9001 19 one D71 170 4.1 (41) 2 + 0.1 M maleic acid Filtracel EFC 9001 19 2 D72 150 0.8 (8) 2 + 0.1 M maleic acid Filtracel EFC 9001 19 four D73 160 0.8 (8) 2 + 0.1 M maleic acid Filtracel EFC 9001 19 3 D74 170 1.2 (12) 2 + 0.1 M maleic acid Filtracel EFC 9001 19 2

Claims (20)

1. A method of treating hydrocarbon paraffins, including carrying out hydrothermal treatment of metal-oxygenate components contained in hydrocarbons obtained by the Fischer-Tropsch method at temperatures above 100 ° C, where hydrothermal treatment is carried out with water at a temperature of from 100 to 400 ° C, and hydrothermal treatment produced after passing through the first filtration zone at a pressure of 0.1-10 MPa for 1-60 minutes, and, in order to carry out hydrothermal treatment, water is added. 2. The method according to claim 1, further comprising chemically treating the metal oxygenate components contained in the Fischer-Tropsch hydrocarbons with organic acids and / or anhydrides to modify metal oxygenates. 3. The method according to claim 1, in which the specified processing is followed by one or more of the following processing operations:
(i) filtering the modified metal oxygenates at the end of a period of time sufficient for the growth of particles and / or their adsorption on a filterable particle;
(ii) adsorption of the modified metal oxygenate on the adsorbent. 4. The method according to claim 1, in which the metal oxygenate is a metal carboxylate, a metal alkoxide, or a combination of these components. 5. The method according to claim 1, in which the hydrothermal treatment is carried out at a temperature of from 120 to 370 ° C. 6. The method according to claim 1, in which the water used for hydrothermal treatment is a combination of reaction water already present in the hydrocarbons obtained by the Fischer-Tropsch process and water added to carry out hydrothermal treatment. 7. The method according to claim 1, in which the hydrothermal treatment is carried out essentially in a system consisting of a single liquid phase in which both hydrocarbons and water are present, and water is present in an amount sufficient to form essentially one liquid phase under conditions carrying out the method. 8. The method according to claim 1, in which the hydrothermal treatment is carried out in the presence of an adsorbent. 9. The method of claim 8, in which the adsorbent comprises silicon oxide. 10. The method according to claim 9, in which the adsorption of the modified metal oxygenates occurs on particles of silicon oxide, and then these particles are recovered by filtration. 11. The method according to claim 2, in which the possible chemical treatment includes a trans-esterification carried out to exchange longer hydrocarbon chains of carboxylic acids or alcohols for shorter chains of carboxylic acids. 12. The method according to claim 11, in which the chemicals used in the operations of transesterification or substitution of ligands are selected from the group consisting of oxalic acid, acetic acid, propionic acid, salicylic acid, succinic acid, tartaric acid, lactic acid, malonic acid, glycic acid, citric acid, maleic acid, fumaric acid, phthalic acid and the anhydrides of these acids. 13. The method according to claim 1, in which hydrothermal treatment leads to hydroxylation and the formation of one or more metal hydroxides and metal oxyhydroxides. 14. The method according to claim 2, in which the hydrothermal treatment is carried out before, during or after a possible chemical treatment. 15. A method of treating hydrocarbon paraffins, including the chemical treatment of metal-oxygenate components contained in hydrocarbon paraffins obtained by the Fischer-Tropsch process, with one or more chemical processing reagents selected from organic acids and anhydrides, carried out in a single liquid phase to modify oxygenates metals. 16. The method according to clause 15, in which the specified chemical treatment is followed by one or more of the following processing operations:
(i) filtering the modified metal oxygenates with filter material at the end of a period of time sufficient for the growth of particles and / or their adsorption on filterable particles;
(ii) adsorption of the modified metal oxygenate on the adsorbent. 17. The method according to clause 15, in which the reagents for chemical processing used in the operations of transesterification or substitution of ligands, are selected from the group comprising oxalic acid, acetic acid, propionic acid, salicylic acid, succinic acid, tartaric acid, lactic acid , malonic acid, glycic acid, citric acid, maleic acid, fumaric acid, phthalic acid and the anhydrides of these acids. 18. The method according to clause 15, in which the chemical treatment is carried out in a system consisting of a single liquid phase, in which there are both hydrocarbon paraffins and one or more chemicals for chemical treatment, the concentration of the specified chemical reagent (s) present is less than the concentration of its (their) saturated solution in hydrocarbons. 19. The method according to clause 16, in which one or more substances from the series including adsorbents, filter material and filterable particles, are selected from the group comprising at least clays, silica, aluminosilicates, silicon-containing aluminas, cellulose, activated carbons sintered metals, titanium oxide and cloth filters such as nylons and polycarbonates. 20. The method according to clause 16, in which the adsorbents are added during chemical treatment.