Way catalytic partial oxidation of natural gas, the method of synthesis of methanol, fischer-tropsch synthesis

 

(57) Abstract:

Way catalytic partial oxidation of natural gas to produce synthesis gas and formaldehyde, combined with the processes of hydrogenation of the resulting CO, such as the synthesis of Fischer-Tropsch and methanol. This oxidation is carried out using a catalyst formed by one or more compound of the platinum group metals, which has the form of a wire mesh or supported on a carrier made of inorganic compounds, so that the content of the metal or metals of the platinum group in the weight percentage is in the range of 0.1 - 20% of the total weight of catalyst and carrier, by carrying out the process at temperatures in the range 300 - 950oC, at pressures in the range of 0.05 -5 MPa, at space velocities in the range of 20000 -150000 h-1. 3 S. and 4 C.p. f-crystals, 3 ill., 8 table.

The present invention relates to a method of catalytic partial oxidation (which in this patent application will be briefly referred to as "CCO") of natural gas to produce synthesis gas and formaldehyde; more specifically it relates to the production of synthesis gas for the Fischer-Tropsch process (f-T), to methods for the synthesis of methanol and mixtures of meta the ez-gas produced by the methods of conversion with steam, Autoterminal reforming, non-catalytic partial oxidation of hydrocarbons. The processes of conversion of steam to catalytically convert a mixture of hydrocarbons and water vapor (H2O/C = 2.5 - 3.5 (volume/volume) mixture of CO and H2with respect to H2/CO usually around 3 in the case when the starting material is natural gas. The main reactions that describe this process are the following:

CnHm+ nH2O ---> nCO + (m+n/2)H2[1]

H2O + CO ---> CO2+ H2[2]

The relation of H2O/C in the reaction mixture is determined by the conditions of temperature and pressure at which carry out the reaction, as well as the need of inhibition of the reaction of formation of coal [3] and [4]:

CnHm---> Cn+ m/2 H2[3]

2CO ---> C + CO2[4]

Usually used in this process, the catalysts based on Ni deposited on the media - oxides of Al, Mg and Si. Applied media exhibit high thermal stability and mechanical strength characteristics. Reactions take place inside the tubular reactors in the combustion chamber. Pressure in the pipes in typical cases lie in the range from 1 to 5 MPa, and the temperature at the outlet of the pipe is usually higher than 850oC (see, for example, "Catalysis Sci is lo 5 seconds. Along pipes for reforming (approximately 15-meter length), which are completely filled with the catalyst, there are large gradients in the composition of the gas mixture.

How non-catalytic partial oxidation of the less widely used and applied for the conversion of mixtures of hydrocarbons, oxygen, water vapor and air in the synthesis gas with the relationship H2/CO is typically about 2, if the starting material is natural gas. The chemistry of this process can be represented by equations [5] and [2].

CnHm+ n/2O2---> nCO + m/2H2[5]

The equipment installed at the present time companies Texaco and Shell (see Hydrocarbon Processing; April 1990, p. 99), equipped with adiabatic reactors, in which the starting reaction with the use of nozzles, where most reactions are complete combustion of hydrocarbons [6]:

CnHm+ (n+m/2)O2---> nCO2+ m/2 H2O [6]

As a result of these reactions are allocated large amounts of heat, water vapor and CO2. The heat causes the reactions of cracking mesogenic hydrocarbons and promotes the reaction of conversion of water vapor and CO2[1], [7].

nCO2+ CnHm---> 2nCO + m/2 H2[7]

Temperature is up to 12 MPa. The process requires a very small residence time of the mixture of the reactant/product inside the reactor (about 0.5 seconds). Since in the reaction mixture used relations O2: CH4usually more than 0.6 (volume/volume), we obtain the synthesis gas contains a large amount of CO2.

Processes Autoterminal reforming carried out inside an adiabatic reactor, introducing a mixture of hydrocarbons, oxygen and water vapor; in addition, in this case, the relation O2:CH4exceed the stoichiometric value of 0.5. In the first reaction zone through nozzles begin the reaction of complete combustion of hydrocarbons [6], in the second reaction zone within the layer of catalyst happen reactions conversion of water vapor [1] and CO2[7]. In the catalytic layer are used catalysts exhibiting the same characteristics as the catalysts described above for the conversion of water vapor. In Autoterminal reforming obtained a mixture of synthesis gas with the relationship H2: CO, intermediate between the relations found for the synthesis gas produced during the conversion of water vapor, and non-catalytic partial oxidation, respectively. The temperature at the reactor outlet in tipis what about the above. The pressure inside the reactor is in the range from 2 to 4 MPa. Stay inside the catalytic layer is about 0.7 seconds.

The synthesis gas is mainly used in the synthesis of f-T to produce a hydrocarbon mixtures, methanol synthesis and in the synthesis of ammonia.

Processes f-T mainly implemented by Sasol in South Africa and use the synthesis gas obtained from coal by gasification or in the process of methane conversion. The investment costs for equipment Sasol is divided up as follows (see M. E. Dry, The Fischer-Tropsch synthesis - Commercial aspects" Catal. Today, 1990, 6, 183):

- coal mining, the production of water vapor and O2- 47%

- production of synthesis gas - 23%

- synthesis f-T - 30%

As you can see, the cost of coal production and conversion and the cost of producing synthesis gas make up about 70% of the total cost of the process, and the production of fuel from coal is economically profitable, if available coal at the price of much lower oil prices. The mixture of synthesis gas, obtained by the process Sasol contain relations H2:CO in the range from 1.7 to 2.

Synthesis f-T leads mainly to the preparation of hydrocarbons by the equation [8]:

2nH2+ nCO ---> CnH2n+ nH2O [8]

In dei is unsaturated, linear and branched hydrocarbons.

Basically, in currently available technologies flow hydrogenation of carbon monoxide generated in the process of conversion of water vapor, Autoterminal reforming and partial oxidation requires a methane content of less than 5%.

The reaction of hydrogenation of carbon monoxide in mixtures of pure CO and H2find performance conversion less than 70%. Low content of methane in the synthesis gas required to increase the partial pressures of CO and H2and prevent reduction of the capacity of the conversion due to the kinetic and thermodynamic constraints, as is the case in the CO hydrogenation reactions. Performance decreases conversion rates leads to increased quantities of reagents that need to be returned for reprocessing, and CH4accumulated during recyclo.

In accordance with the above arguments, the goal is the achievement of the performance values of methane conversion over 95%. Since 1985 developed methods for the synthesis of diesel fuels from natural gas, which are based on the intermediate production of synthesis gas, the synthesis of f-T hydrocarbon long chain is RNO 60% of the total cost of production.

The cost of producing synthesis gas contributes the same percentage contribution in the overall cost of the conventional process for production of methanol at temperatures of from 220 to 300oC.

Therefore, in the synthesis of f-T and the synthesis of methanol is carried out by conventional methods, using a mixture of synthesis gas with negligible methane content in order to prevent reduction of reaction rates and, consequently, the output of the conversion on the passage and accumulation of methane in the recycled gas to the stage of synthesis, which may be caused by the reduction of partial pressures of H2and CO.

In contrast, in the synthesis of methanol with high performance conversion pass conducted at low temperatures, it is possible to convert approximately 90% of the synthesis gas to methanol even in the presence of large quantities of inert gases. However, in this case, in the reaction mixtures invalid impurities CO2and H2O.

This method is mainly investigated in Shell (EP-285 228; EP-287 151; EP-289 067; EP-306 113; EP-306 114; EP-309 047; EP-317 035), Brookhaven National Laboratories (US-4935395; US-4614749; US-4 623 634; US-4 613 623), Mitsui (JP-81/169 934; JP -82/I28 642), Sintef (WO-86/3190), Snamprogetti (IT 20,028 A/88; IT 23,101 A/88; IT 23,102 A/88; IT 22,352 A/89; EP 357 071, EP-504 981(CuCl/NeONa, chromite copper/MeONa), and the synthesis is carried out in slurry reactors. Reactions take place in the temperature range from 90 to 120oC and in the pressure range from 5 to 50 ATM. In these conditions, the achieved performance of conversion of about 90% and a selectivity of more than 95% when using mixtures of CO and H2(relationship of H2:CO = 2 (volume/volume) with a high content of inert molecules such as nitrogen and methane (in typical cases were investigated reactions with the content of inert substances about 40%).

In addition, the synthesis of mixtures of methanol-dimethyl ether can be carried out with high performance values conversion on a pass, because the formation of dimethyl ether with subsequent conversion of methanol conducive to achieving complete conversion of the mixture of CO/H2[J. Bogild Hansen, F. Joensen - Stud. Surf. Sk. Catal., 61 (1991), 457]. Therefore, in this case, the reaction can also be carried out in the presence of inert gas such as unconverted methanol.

In this paper we found a way catalytic partial oxidation (CCO) of natural gas to produce synthesis gas, which is used a catalyst containing a noble metal, and which is carried out at high flow rate (SWOC)of low molar relationship O2: C and H2O:CH4; however, this method can effectively be combined with the processes of hydrogenation of carbon monoxide, such as the synthesis of f-T synthesis of methanol or mixtures of methanol-dimethyl ether.

A byproduct of this method is formaldehyde, which is separated before using synthesis gas, if it is formed in relatively large amounts, for example in excess of about 3% by weight.

The possibility of conducting the process at space velocities (1500000 > SCSPS > 20000 h-1, SSPG - hourly average gas flow rate) higher than currently used (SCSP < 10000 h-1) allows the use of small reactors, which allows to achieve savings in investment cost. The ability to work with streams of reagents with a molar relationship O2: CH4<0,5 (volume/volume) can reduce energy consumption and investment cost of the device for producing oxygen.

Way catalytic partial oxidation of methane [12] carried out at space velocities of less than 15000 h-1can be described as the sum of the reactions of complete combustion of hydrocarbons [9] and the conversion of water vapor and CO2[10]-[11] .

O + CH4---> CO + 3H2O [11]

CH4+ 1/2O2---> CO +2H2[12]

At temperatures below 600oWith a strongly exothermic reaction of complete oxidation of [9] is greatly beneficial, in that time, as the flow is strongly endothermic reactions conversion of water vapor and CO2[10]-[11] unprofitable. Conversely, at temperatures above 750oC both of these latter reactions can lead to the conversion of CO2and H2O in the synthesis gas.

The catalysts used in stage CCO according to this invention, allows for reactions with relations O2:CH4less than 0.5 in the absence of water vapor, in conditions that cannot be implemented in real time using the known prototypes of the catalysts due to the reaction of formation of coal [3] and [4]. The synthesis gas obtained in these conditions, it may even contain large quantities (up to 50%) of unreacted methane and can be used in reactions for the synthesis of high value performance conversion pass.

On the influence of high values of flow rate reported in published studies D. A. Hickman and L. D. Schmidt (Science 1993, 259, 343), who conducted experiments at temperatures above 1000ooC catalysts, which was not part of noble metals (Fe, Co, Ni). The experimental tests described in this patent application are different from those described in the published articles. The above authors used the catalysts investigated different from us, and, therefore, could not work with relations O2:CH4< 5 (volume/volume) in order to avoid reaction of formation of coal [3], [4] and avoid getting HCHO; moreover, the way CCO of the present invention allows to obtain a synthesis gas in SWOS even in the presence of large quantities of CO2. The possibility of using CO2in the reaction mixture gives the possibility of obtaining significant advantages in all cases, when you want to obtain a mixture of synthesis gas with a ratio of H2:Less CO 2 (volume/volume). Such a low value of this ratio is advantageous for obtaining hydrocarbons, long-chain and high molecular weight in the synthesis of f, As we have already briefly noticed hydrocarbon products with a long chain can be turned into diesel fuel for motor vehicles.

At high values of bulk velocities used in the proposed method, CCO significantly ISM and values of selectivity even at low temperatures. The catalysts used in experimental studies of CCO by the proposed method are significantly different from those described in the technical articles because they contain very small amounts of noble metal (up 0.1%).

I believe that the reaction of a synthesis gas can be represented in the following form:

< / BR>
According to modern concepts, it is believed that under conditions of high flow rate can be obtained from the primary products of the oxidation reactions of CO and H2who then quickly removed from the catalyst surface before entering into reaction with the formation of secondary products.

The first object of the present invention, a method of catalytic partial oxidation of natural gas to produce synthesis gas and formaldehyde is characterized by the fact that such oxidation is carried out using a catalyst formed by one or more compound of the platinum group metals, which have the form of a wire mesh or supported on a carrier of inorganic compounds so that the percentage by weight of the metal or metals of the platinum group is in the range from 0.1 to 20%, preferably from 0.1 to 5% of the total weight can produce 350 to 850oC, at pressures in the range from 0.5 to 50 atmospheres, preferably from 1 to 40 atmospheres, at space velocities in the range from 20,000 to 1,500,000 h-1preferably from 100000 to 600000 h-1.

Used catalysts are particularly active in relation to the reactions of CCO and especially inert to the reaction of formation of coal [3], [4], and even have the ability to work with relations O2:CH4less than 0.5 (volume/volume) and in the presence of CO2without loss of activity. In those cases, when the ratio of O2: CH4less than 0.5, the flow leaving the reactor CCO will contain large amounts of unreacted methane.

If the reaction of CCO conducted using mixtures of reagents with relations O2/CH4equal to 0.65 (volume/volume), the methane content in the output streams can be reduced to levels even below 5%.

As already briefly indicated, the catalysts of CCO containing platinum group metals, in the form of tablets, which are obtained according to the procedures described in the patent literature (UK Patent No. 2 240 284, UK Publ, No. 2 247 465, IT M192A 001 953, UK Publ. N 2 274 284). In addition, at the stage of CCO can use the grid wires of precious metals, similar to PR the particular for the last case of the proposed method describes the original method of preparing a monolithic catalysts, allowing you to quickly apply noble metals with a high degree of dispersion on the surface of the solid body by immersing the latter in a solution of ORGANOMETALLIC clusters, Rh, Ru and Ir in an organic solvent. The metals are fixed on the surfaces of the solid body by cordovano-liquid-phase reaction between the reactive centers on the surface and ORGANOMETALLIC clusters, which are then decomposed with the formation of monatomic particles in extremely fine condition. This procedure differs significantly from the method of impregnation, since the content of the noble metal attached to the carrier is determined by the number of active sites on its surface.

A further object of the present invention are combined the methods of synthesis of methanol or mixtures of methanol/dimethyl ether, as well as syntheses F.-T.

United way of the synthesis of methanol from synthesis gas mainly consists in carrying out the reaction of the synthesis gas obtained by the above method, after a possible pre-separation images of the Oka conversion on a pass (after an additional branch of the CO2and H2O from the specified synthesis gas) at temperatures above 40oC and below 200oC and at a pressure above 1 MPa, or, in the case of syntheses carried out in the usual way, at temperatures above 200oC and below 350oC and at a pressure of 0.3 MPa.

United way of the synthesis of mixtures of methanol-dimethyl ether is the reaction of a mixture of synthesis gas and methane obtained as described above, after a possible preliminary separation may formed of formaldehyde, in the presence of catalysts capable of producing methanol and transform thus obtained in methanol dimethyl ether by carrying out the process at temperatures above 150oC and below 400oC and at a pressure of above 0.1 MPa to 10 MPa.

United way of synthesis f-T from synthesis gas mainly consists in carrying out the reaction of the synthesis gas obtained in the above way, after a preliminary separation may formed of formaldehyde, if desired, in the presence of a suitable catalyst by carrying out the process at temperatures above 200 and below 400oC and at a pressure above 1 MPa.

The presence of methane in the reaction mixture in the present case, considerable cost reduction which can be achieved in a method of producing synthesis gas, can identify with the benefits of the United ways of converting natural gas into liquid hydrocarbons and/or oxygenated products via synthesis gas containing more than 5% methane by volume.

The above combined methods is shown schematically in Fig. 1 - 3.

In Fig.1 schematically shows a combined method of synthesis f-T from natural gas via synthesis gas obtained by the method according to the present invention.

Natural gas (1) and oxygen (2) is introduced into the reactor (3), where the catalytic partial oxidation of natural gas to form synthesis gas and formaldehyde.

Formaldehyde (4) may be separated from the synthesis gas (5) that enter the reactor (10), which are the syntheses F.-T.

Facing the product (11) is sent to the separating device (12) which leave the thread (13), containing hydrocarbons with two or more carbon atoms and water, and the stream (14) containing methane and hydrocarbons with two or less carbon atoms, the latter stream is sent for re-processing in the reactor (3).

In Fig. 2 schematically shows the combined Natural gas (1) and oxygen (2) are fed into the reactor (3), where is the catalytic partial oxidation of natural gas to form synthesis gas and formaldehyde.

Formaldehyde (4) may be separated from the synthesis gas (5) that enter the reactor (20), which are the syntheses of methanol or mixtures of methanol-dimethyl ether.

The exiting product (21) is sent to the separating device (22), from which come the flow (23) containing methanol and oxygen-containing products, and the stream (24) containing methane and hydrocarbons with two or less carbon atoms, the latter stream is sent for re-processing in the reactor (3).

In Fig. 3 schematically shows the combined method for the synthesis of methanol from natural gas via synthesis gas under conditions of high performance conversion pass.

Natural gas (1) and oxygen (2) are fed into the reactor (3), in which the catalytic partial oxidation of natural gas to form synthesis gas and formaldehyde.

Formaldehyde (4) may be separated from the synthesis gas (5) that after the separation of CO2and H2O (7) in the device (6) are fed into the reactor (30), in which the methanol synthesis.

The exiting product (31) is sent to the methane, which is sent for re-processing in the reactor (3).

The cheapness of these methods is facilitated by the possibility of separation from the final products of the reaction, unreacted light (C1and C2) hydrocarbons and their re-direction in the device for CCO.

In more detail, in United way of obtaining and use of synthesis gas in the device for CCO you can apply a mixture of natural gas and oxygen or enriched air, in which the molar relationship O2/CH4can be even less than 0.5, even in the absence of water vapor. In the way of CCA of the present invention can also be used in conditions of SWOS (high bulk velocities) of a mixture of CH4/O2/CO2that does not contain water vapor. The process conditions are such that the device for producing synthesis gas oxygen will undergo a full conversion, while in coming out of the reactor CCO flow can be a significant amount of methane, in particular with respect to O2:CH4less than 0.5.

The reaction products of CCO consist mainly of mixtures of H2, CO and CH4small quantities of H2O and CO2while, a byproduct of the reaction is HCHO. After separation of formal2used for the synthesis of methanol and/or dimethyl ether (IER) and/or hydrocarbons.

In the case when the flows coming from the unit to produce synthesis gas, remain large amount of unreacted methane, the latter remains as inert substances during a subsequent station for the synthesis of hydrocarbons and/or oxygen-containing products, it is easier to separate from the heavier products of the reaction and return to repeat the processing in the device for CCO.

These results are very difficult to achieve under conditions of high pressure; on the contrary, surprisingly, it was found that by using such methods described above can be achieved reactions and changes in selectivity at pressures above atmospheric. If the production of synthesis gas in SWOS is designed for methanol synthesis with high performance values conversion pass will be used reaction conditions, in which all the oxygen is consumed, and present in the synthesis gas CO2and H2O will be removed before the stage hydrogenation.

The results obtained from the experimental tests described in the following examples, show that in a wide range of conditions ek is wakisi carbon as intermediates in the reaction of [9] . Thus, high performance conversion can be achieved at low temperatures and under conditions of high flow rate because the reaction [12] is very fast and is thermodynamically favorable over a wide temperature range (temperature range from 25 to 800oC its equilibrium constant is about 1016in that time, as the reaction of [10] and [11] slow and thermodynamically unfavorable at temperatures below 750oC. High outputs of the synthesis gas to be achieved even at low temperatures when using mixtures of CH4and O2relations O2:CH4< 0.5 (volume/volume), give special advantages to carrying out reactions for methanol or mixtures of methanol-dimethyl ether using high performance conversion pass.

To better illustrate the invention the following are a few examples, although it is clear that it is not limited to them.

Example 1.

The reaction of CCO and methanol synthesis at high performance conversion on a pass from the obtained mixtures of synthesis gas and methanol was carried out in two reactors at a pressure of 1.5 MPa.

In the reactor "A" was carried out by reaction of CCO EA with temperature 750oC, cooled with the use of the coil from flowing inside the water and sent (after removal of small amounts of water vapor and CO2formed during the synthesis with CCO) in reactor B with temperature 100oC for methanol synthesis.

The mixture of the reaction products were analyzed as the output of the first and second reactors, in both cases using gas chromatography.

The reactor, inside which are the reaction CCO, is an alumina ceramic tube surrounded by a steel cylinder. Alumina tube provides chemical inertness of the walls of the reactor, and steel pipe forms a strong body that allows a pilot test at pressures above atmospheric.

The reaction gas consisting of CH4and O2(O2:CH4= 0.2:0.8 volume/volume) passes through the catalytic layer (A) containing 0.5 g of the catalyst based on Rh and Ru with a contact time of 10-2seconds (SCSP 300000 h-1).

Noble metals supported on a carrier formed of alpha-alumina, grafted silica. The content of the Ph and EN are respectively 0.5% and 1% (by weight) of the material. Media (alumina, grafted DV is mA and tetraethylsilane (TPP), followed by hydrolysis and calcination. Precious metals were applied using hydrocarbon mixtures Rh4(CO)12and Ru3(CO)12in accordance with the procedures described in UK Patent N 2240284, UK Publ. N 2247465, IT M192 A 001 953, UK Publ. N 2274284.

The mixture of products obtained at the stage of CCO, is included in the slurry reactor "B" for methanol synthesis. The catalytic system in the slurry reactor was prepared using as starting substances CuCl and MeONa by conducting the process in accordance with the procedures described in EP-375,071. Salt of copper and the alkali metal alkoxide was placed in a reactor with a covering layer of a nitrogen atmosphere. Then add the solvent (90 ml thoroughly drained of anisole in the presence of methanol (40 mmol). The molar concentration of the alkoxide was maintained at a level of about 2 M salt concentration of copper was 0.06 M During the early stage of the process, the reactor was sealed and filled with 15 ATM with a mixture of CO and H2(H2:CO = 2:1 volume/volume), and the temperature is raised to 100oC before it entered the reaction mixture from the reactor, CCO. Table 1 provides data on the composition of mixtures of products at both stages of the reaction.

The performance of the conversion of synthesis gas to methanol synthesis status and therefore the result is 65 g MeOH /h-l reactor volume.

Example 2.

In this case, the stage of synthesis gas production was carried out in the reactor "And" at 1.5 MPa, at a temperature of 750oC on the monolithic catalyst containing Rh and Ru. The mixture of reagents (SSPG = 300000 h-1) contained methane and oxygen in the relation O2:CH4= 0.29:0.71. Stage hydrogenation of carbon monoxide with the aim of obtaining methanol in the presence of unreacted methane was carried out by passing the reacted slurry flow through the reactor at 1.0 MPa and a temperature of 95oC.

Monolithic catalyst was obtained by lowering a monolithic piece of alumina in a solution of aluminum hydroxide. The hydroxide layer covers a monolithic piece, and after drying and calcination, it turns into a porous hydroxide layer. After this treatment the surface area of the monolithic piece is 12 m2/g (this method is called in the relevant technical literature wach-coating" process - a way to "wash coating"). The solid piece was soaked in hydrocarbon solution of Rh4(CO)12and Ru3(CO)12(hexane, Rh: Ru:Ir = 0.1:0.5:0.5 mol/mol) for 2 hours. In these conditions occur the reactions of dissociative chemisorption of clusters resulting coating is m the final metal content (0.08% Rh, 0.4% Ru, 0.3% Ir).

The catalyst for the reactions of synthesis of methanol was prepared by mixing CuCl (6 mmol), CH3ONa (80 mmol), methylformate (50 mmol) with 90 ml of anisole. The experiments were carried out in accordance with the same operating procedures that have been described in the above example 1; the results are given in table 2.

Conversion of synthesis gas to methanol synthesis was 92% and the selectivity for methanol - 98%.

Example 3.

The reaction of synthesis gas production was carried out in the reactor And above the catalyst layer at a pressure of 3.0 MPa (SSPG = 400000 h-1), the outlet temperature of 750oC, O2:CH4= 0.41 (volume/volume). The resulting synthesis gas, containing more than 10% unreacted methane was used in the second reactor "B" to carry out the reactions of f-T synthesis of hydrocarbons. The pressure in the reactor B was maintained at 3 MPa, and the temperature - 300oC.

In the synthesis of CCA used monolithic catalyst, prepared according to the procedure described in example 2. Catalyst for the synthesis of f-T was prepared by successive impregnate gamma alumina (surface area 150 m2/g) until you see signs of moisture. First Impregilo second impregnation with an aqueous solution of ruthenium nitrate, and then the second procedure of drying. The third stage of impregnation was carried out with an aqueous solution of potassium carbonate. After further drying, the catalyst was progulivali to 350oC. the Final catalyst contained 18% cobalt, 2.5% ruthenium and 1% potassium. Catalytic testing was preceded by a regenerative thermal treatment at 350oC, during which through the reactor "a" and "B" blew a stream of nitrogen containing 25% hydrogen. The compositions of the reaction mixtures and products of both stages of the reaction are shown in table 3.

Example 4.

Repeat the procedure described in example 3, using the same catalyst for the reactions of CCO and accordingly the same catalyst for the synthesis of f-T; however, in this case, a mixture of methane and oxygen supplied to the reactor inlet for CCO, had O2:CH4= 0.55. The results are shown in table 4.

Examples 5-7.

Repeated the experiments described in examples 1, 2 and 4, using in the first reactor CCO as a catalyst mesh platinum-rhodium wire containing 10% rhodium by weight. This grid has the same features as wire mesh used in the oxidation of am is Dios particularly active in reactions of CCO and especially inert in the reaction of formation of coal, grid modified by electrochemical deposition on their surface metal layer of rhodium from aqueous solutions of rhodium nitrate. Found the activity of the material obtained in the reactions of CCO held in SWOS, selectively on CO and H2more than 95% under the reaction conditions described in examples 1-4, but with lower selectivity to formaldehyde. In the following tables 5, 6 and 7 show the results related to the first reaction stage, in which the mixture of synthesis gas.

Example 8.

In this case, during the first passage of the synthesis gas was used catalysts from example 2, but the mixture of reagents was CH4:O2:CO2= 1: 0.5:0.5; at the same time, on the next stage of the synthesis f-T was used the catalyst described in example 3. At the stage of CCA used the following process conditions: SSPG = 400000 h-1P = 3 MPa, at the reactor outlet T = 750oC. For synthesis reactor f-T was used in the following conditions: SSPG = 1500 h-1P = 3 MPa, T = 300oC. the results are shown in table 8.

1. A method for production of synthesis gas by catalytic partial oxidation of natural gas, and the oxidation is carried out using katonai grid or supported on a carrier, made from inorganic compounds in such a way that the content of metal or platinum group metal by weight is 0.1 - 20% of the total weight of catalyst and carrier, at pressures in the range of 0.05 to 5 MPa, wherein the oxidation process is carried out at temperatures in the range 300 - 950oWith space velocities in the range of 20,000 - 1500000 h-1with the release of formaldehyde as a by-product of oxidation.

2. The method according to p. 1, characterized in that the temperature range 500 - 850oWith pressure in the range 0.1 - 4 MPa, and the flow rate is in the range of 100,000 - 600000 h-1.

3. The method according to p. 1, characterized in that the weight percentage of the metal or metals of the platinum group is in the range of 0.1 - 5% by weight of the total weight of catalyst and carrier.

4. The method according to p. 1, characterized in that the platinum group metals selected from among rhodium, ruthenium and iridium.

5. The method according to one of paragraphs.1 to 4, characterized in that the molar ratio of O2: CH4below 0.5.

6. The method of synthesis of methanol from synthesis gas by the reaction of the synthesis gas obtained by the method according to one of paragraphs.1 to 5, after possible pre-separation is nazov with high conversion per pass after an additional branch of the CO2and H2O from the specified synthesis gas is carried out at temperatures above 40oWith and below 200oC and at a pressure above 1 MPa, and in the case of syntheses carried out in the usual way, at temperatures above 200oWith and below 350oC and at pressures above 1 MPa.

7. The method of synthesis of Fischer Tropsch (f-T) synthesis gas by the reaction of the synthesis gas obtained by the method according to one of paragraphs.1 to 5, after a possible preliminary separation of the formed formaldehyde using a suitable catalyst, wherein the process is carried out at temperatures above 200 and below 400oC and at a pressure above 1 MPa.

 

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