Method of producing acetylene from methane
SUBSTANCE: invention relates to a method of producing acetylene through oxidative pyrolysis of methane in the presence of oxygen and a catalyst, characterised by that the catalyst is heated to 700-1200°C by passing electrical current through it. The catalyst used is a fechral alloy which is thermally treated on air at temperature 900-1100°C. The ratio of methane to oxygen is varied in the range of 5:1-15:1.
EFFECT: high output and selectivity of the process.
2 cl, 17 ex, 1 tbl, 1 dwg
The invention relates to the field of oil refining, petrochemical and gas processing, namely the method of producing acetylene from methane.
As you know, still there is no acceptable technology use and associated oil gases that tens of millions of tons per year are burned in flares. There are several directions for the development of technologies for utilization of this hydrocarbon, which conducted the study. This is, for example, the decomposition of C1-C3paraffins to produce hydrogen as the main target of the product. The other way is the transformation of natural gas in chemical products, which is based on a complex energy - and capital-intensive process prior conversion to synthesis gas.
Recently, interest single-stage process for conversion of methane in chemical products, such as high temperature (≥900°C) oxidative pyrolysis of C1-C3gas to acetylene. The fact of formation of acetylene by incomplete combustion of hydrocarbons known for a long time (Evlanov SF, Lavrov NV // Scientific basis for the catalytic conversion of hydrocarbons, 1977, s-232). When optimizing the yield of acetylene emphasis on the construction of the different types of burners and selection of different conditions of combustion of hydrocarbons. The process of oxidizing pyrolysate several features: a very short duration of initial substances in the reactor (a few milliseconds), the high reaction temperature (1200-1400°C), pressure is atmospheric or slightly increased, quenching the reaction products to a temperature below 300°C using as a cooling medium of water or oil quenching prevents the decomposition of the produced acetylene carbon and hydrogen).
In the patent EP No. 0178853 is a technology according to which part of the methane is partially burned, and high temperature gas mixture (T>1000°C) is passed through a fluidized bed or flowing layer of particles of inert material: fireclay, quartz, corundum, Zirconia, silicon carbide, etc. to reduce the temperature gradient in the gas stream. The maximum selectivity and yield With2+-hydrocarbons equal to 30% conversion of methane 62.8% at 1151°C.
The disadvantage of this method is that part of the methane consumed as fuel to heat the entire mass of gas to 1200-1400°C. in Addition, to save less strong than methane molecules With2+hydrocarbons used hardening of the whole mixture of water, i.e. rapid cooling of the mixture to ~300°C, which complicates the technology.
The study of the oxidative condensation of methane, in which the focus was on finding catalysts and study of the reaction mechanism occurring at 650-850°C (Usanational, the.Acrylol. Oxidative conversion of methane. M.: Nauka, 1998). It is at these temperatures (650-850°C) it is possible to obtain significant yields of ethane and ethylene in the oxidation of methane.
Closest to the present invention is a method of producing hydrocarbons From2-C4where was first used the term "catalytic oxidative pyrolysis of methane" (As the USSR №1216937, prototype). This method is carried out at between 800 and 950°C, contact time of 0.1-2.5 sec, the content in the initial mixture 10-20 vol.% oxygen and 90-80% vol. methane in the presence of a catalyst composition, mol.%: Bi2O30,95-to 7.59 and MeO 92,41-99,05, where Me is Mg, Ca, Sr, BA. The catalyst was allowed to increase the yield of hydrocarbons From2+up to 10 mol.% on missed methane selectivity was 78.5%. Nevertheless, the main products are ethane and ethylene. Acetylene in the resulting mixture and the conversion of methane is very small - up to 20%, which gives low outputs by product.
The purpose of this invention is to increase the yield and selectivity of the process for acetylene through the use of the catalyst of a new type and changes in technology oxidative pyrolysis.
The proposed method of producing acetylene, oxidizing pyrolysis of methane in the presence of oxygen comprises using as the catalyst heat-treated in air at 900-1100°C terralavoro alloy in the form of spirals, ribbons, art is Rina and other forms. Heating of the catalyst is carried out by passing through it an electric current to a temperature of 700-1200°C., and the ratio of methane: oxygen change in the range 5:1 to 15:1.
Contact oxygen-containing mixtures on the basis of methane in certain proportions of CH4/About2(air) with wire working fehrle, heated and electric current to temperatures from 750°C to >1200°C gives the catalytic effect of the change in selectivity With2the hydrocarbon compared with the gas, oxidizing pyrolysis of methane. The gas mixture is served cold, and only contact with the heated ferralium alloy leads to the catalytic effect. As the gas mixture is served cold, the overshoot part of the cold gas leads to a dramatic cooling of the reaction products formed upon contact with high temperature wire, i.e. hardening of the products of oxidative pyrolysis and increase the output of C2hydrocarbons (primarily ethane.
As the catalyst used alloy "wire" in the form of various shapes, mostly in the form of a wire diameter of 0.25 mm
Grade: X 23 W T, composition: up to 0.05%; Si - 0.5%; Mn - 0.3%; Ni - 0.6%; S - up to 0.015%; P to 0.03%; Cr - 22-24% CE - 0.1%; Ti - 0,2-0,5%; Al - 5-5,8%; Ca - up to 0.1%; the rest of the iron. Manufacturer - JSC metallurgical plant Electrostal, GOST 12766 1-90.
is the preparing of fehrle included several operations: wire or tape weight of 0.26-0.28 g twisted into a spiral with an outer diameter of 5 mm, was degreased by washing in acetone and progulivali in air in a muffle furnace at 1000°C for 21 h In the result of this oxidative heat treatment on the alloy surface oxide layer consisting mainly of aluminum oxide.
Prepared in this way the coil was placed on a ceramic tube with a diameter of 2 mm and were placed in a flow reactor.
Installation scheme for the oxidative pyrolysis of methane is represented in the drawing: a - front view, b - lateral view. The scheme includes a quartz reactor 1, perlevel spiral 2 on the ceramic tube 3, laboratory autotransformer (Lattre) 4, the window of the optical quartz 5 and the optical pyrometer 6 laser pointing at the spiral.
The reactor operates in the following way. The spiral 1 using LTR and 3 serves voltage, which heats it to the desired temperature from 700 to 1200°C., the Fixing temperature is performed using an optical pyrometer 6 (PD-7, manufacturer JSC "Etalon", Omsk) with laser guidance on the spiral. For this purpose, the reactor is equipped with a window of optical quartz 5. On the hot wire serves the source of the reaction gas. The gas is in contact with the heated spiral in and out. The sample mixture after the reactor is directed to a chromatographic analysis carried out on the chromatograph brand COLOR-500M. Content ostate the aqueous methane, and formed ethane, ethylene and acetylene is fixed with the help of the detector ionization in the flame. Chromatograph conditions were as follows: capillary column with a stationary phase SiO2length 15 m, the pressure of the carrier gas - nitrogen (1 kgf/cm2, air flow 300 ml/min, the flow rate of hydrogen 30 ml/min, column temperature 50°C.
The proposed method is illustrated with examples.
The reaction mixture composition: 15% vol. methane and 85 vol.% nitrogen (without oxygen, the ratio of methane/oxygen 1/0) is passed through the reactor at a temperature of spiral 1100°C with a bulk velocity of 76 ml/min Spiral made of wire with a diameter of 0.25 mm, the methane Conversion and selectivity to products listed in the table.
Similar to example 1, but the reaction mixture passed through the reactor at a temperature of spiral 760°C and 890°C, respectively. The spiral is made of a tape width of 1 mm and thickness of 0.4 mm, the methane Conversion and selectivity to products listed in the table.
Similar to example 1, but the reaction mixture passed through the reactor at a temperature of spiral 970°C. the methane Conversion and selectivity to products listed in the table.
Similar to example 1, but the reaction mixture composition: 15% vol. methane, 1% vol. oxygen (ratio of methane/oxygen 15/1) and 84% vol. nitrogen was passed through the reactor at the temperature of the spiral 1170°C.
Example 6 and 7.
Analogous to example 5, but the reaction mixture passed through the reactor at a temperature of spiral 1000°C and 960°C.
Analogous to example 5, but the reaction mixture passed through the reactor at a temperature of spiral 830°C. the Spiral is made of a tape width of 1 mm and a thickness of 0.2 mm
Analogous to example 5, but the reaction mixture passed through the reactor at a temperature of wire 750°C.
The reaction mixture composition: 15% vol. methane, 1% vol. oxygen (ratio of methane/oxygen 15/1) and 84% vol. nitrogen is passed through the reactor at a temperature of spiral 1160°C and the flow rate through the reactor 80 ml/min
Similar to example 10, but the reaction mixture composition: 20% vol. methane, 1,33% oxygen (ratio of methane/oxygen 15/1) and 78,67% vol. nitrogen is passed through the reactor at a temperature of spiral 1150°C.
The reaction mixture composition: 15% vol. methane, 1,67% vol. oxygen (ratio of methane/oxygen 9/1) and 83,33% vol. nitrogen is passed through the reactor at a temperature of wire 760°C. the flow Rate of 75 ml/min Spiral made of wire with a diameter of 0.25 mm
Example 13 and 14.
Similar to example 12, but the reaction mixture passed through the reactor at a temperature of wire 850°C and 930°C, respectively. The spiral is made of a tape width of 1 mm and thickness of 0.4 mm
Example 15, 16 and 17.
And the illogical example 12, but the reaction mixture passed through the reactor at a temperature of wire 1040°C 1110°C and 1230°C, respectively.
The methane conversion and selectivity to products listed in the table. As can be seen from the table, the invention allows to obtain acetylene with selectivity to 41.8% and an ethylene selectivity of 3.3%, the methane conversion is 56.4%.
Significantly increased total yield for2- hydrocarbons - 25,5% (maximum prototype 9.7%).
1. A method of producing acetylene, oxidizing pyrolysis of methane in the presence of oxygen and a catalyst, wherein the catalyst is heated by passing through it an electric current to a temperature of 700-1200°C as catalyst using heat-treated in air at temperatures of 900-1100°C, fecraly alloy, and the ratio of methane:oxygen change in the range 5:1 to 15:1.
2. The method according to claim 1, characterized in that the heat-treated fecraly alloy used in the form of spirals, ribbons, rods.
SUBSTANCE: invention relates to two versions of a method for synthesis of aromatic compounds, on of which involves: a methanation step involving contact between a hydrogen-containing gas and carbon monoxide and/or carbon dioxide in the presence of a catalyst which causes reaction of hydrogen contained in the gas with carbon monoxide and/or carbon dioxide and conversion of these components to methane and water; and a step for synthesis of an aromatic compound with reaction of lower hydrocarbon with methane obtained at the methanation step in the presence of a catalyst to obtain a gaseous reaction product containing aromatic compounds and hydrogen, where the aromatic compounds are separated from the gaseous reaction products obtained at the aromatic compound synthesis step, and the remaining hydrogen-containing gas is taken to the methanation step. The invention also relates to a method for synthesis of hydrogenated aromatic compounds obtained using methods described above.
EFFECT: possibility of obtaining aromatic compounds through catalytic reaction of lower hydrocarbons.
14 cl, 13 tbl, 3 ex, 2 dwg
SUBSTANCE: aqueous suspension containing earth metal salt, powdered metal chloride and powdered transition metal oxide is made; aqueous suspension is made by dispersing in water the earth metal salt chosen from the group including barium and/or calcium and probably strontium or their combination. Water is added in powdered metal chloride, where powdered metal chloride is chosen from the group including Sn, Mg, Na, Li, Ba. Further powdered transition metal oxide is added being titanium oxide, to water; then plastic binder is added to until paste is formed; paste is dried up paste to powder; powder is heated up at raising temperature following preset temperature profile. Heated powder is baked to produce perovskite catalyst. Suspension contains mixed Ba and/or Ca and/or Sr (0.95mole) + TiO2 + metal chloride chosen from the group Sn, Mg, Na, Li, Ba in amount 0.05 mole.
EFFECT: simplified technology of catalyst producing.
19 cl, 14 ex, 2 tbl, 8 dwg
SUBSTANCE: method of obtaining hydrocarbons C2-C3 by high-temperature catalytic oxidizing conversion of methane lies in supply to reactor, into which catalyst is placed, and whose free volume is filled with inert filling, of initial gas mixture, which contains mixture of methane and molecular oxygen, at rate 50000-70000 m/g/h, catalyst includes into its composition ions of alkali metal, manganese, tungsten and silicon oxide with molar ratio M:W:Mn:Si, where M-Na or K or Rb or Cs, equal 1.8-2.2:1:1.9-2.3:89-92, and is characterised by presence in it of tungsten in oxidation degree W6+, manganese oxidation degrees Mn7+, Mn6+, Mn3+, catalyst being obtained by thermal processing at 200°C and further incineration at temperature 795-799°C of initial solid powder-like mixture, consisting of salts and/or oxides of tungsten, manganese, alkali metal and SiO2, taken in said mole ratio in terms per mole of tungsten, manganese, alkali metal and silicon atoms.
EFFECT: increase of target product output, catalyst productivity, simplification of technology of obtaining target products and reduction of expenditures.
11 cl, 1 tbl, 30 ex
SUBSTANCE: method involves partial burning of a mixture of methane, hydrogen, oxygen and optionally hydrocarbons, which are different from methane in contact with a catalyst, capable of maintaining burning beyond the normal upper flammable limit of fuel, where they react with formation of product, including one or more olefins. In the mixture coming into contact with the above mentioned catalyst, capable of maintaining burning beyond the normal flammable limit of fuel, can be less than 20 molar % (converted to the overall quantity of the hydrocarbons) of those hydrocarbons which are different from methane. In the mixture coming into contact with the catalyst, the volume ratio of hydrogen to oxygen ranges from 5:1 to 1:1 and methane and oxygen are put into the autothermal cracking device in a mixture at hourly average feed rate of more than 70000 h-1.
EFFECT: invention pertains to the method of obtaining olefins from methane.
12 cl, 2 tbl, 2 ex
FIELD: chemical industry; other industries; methods and devices for conversion of the methane by the plasma-catalytic oxidation.
SUBSTANCE: the invention is pertaining to the method for conversion of the methane by the plasma-catalytic oxidation and to the and devices fro the method realization. The method of conversion of methane is conducted by the super high frequency (SHF)radiation plasma-catalytic oxidation with production of ethylene. The method includes activation of the catalyst by the SHF radiation and formation of the non-equilibrium "cold" SHF plasma. Simultaneously exercise activation of the catalyst by the super high frequency radiation and by the SHF plasma and create the non-equilibrium "cold" super high frequency plasma simultaneously in the Е010 type resonator or on Е01 with the symmetry of rotation from the SHF generator and on the total wave Н11° with rotation of the polarization plane of the continuous SHF generator. In the device realizing the indicated process the round waveguide is smoothly transforms into the waveguide with the partial dielectric filling-up and contains the aligner used for reduction of the reflections of the super high frequency energy, the encapsulant for provision of vacuum in the SHF plasma-catalytic reactor and the SHF plasma generation on the butt of the quartz rod, with the located on it quartz plates and the catalyst. The batchers of the uniform feeding of the reactants (СН4 + О2 + Аг) are installed with the capability of rotation and movement with respect to the SHF plasma. The system of the reaction products withdrawal is located in symmetry to the axis of the with respect to the plasmatron. The invention stimulates the increase of efficiency of the conversion process of methane into ethylene.
EFFECT: the invention ensures stimulation of the increased efficiency of the conversion process of methane into ethylene.
9 cl, 2 ex, 4 dwg, 1 tbl
SUBSTANCE: method of processing carbon-carbonate mineral involves burning limestone in a reactor, obtaining calcium oxide, production of calcium carbide by reacting part of calcium oxide obtained from burning limestone with carbon, bringing part of the obtained calcium carbide into contact with water, obtaining acetylene and caustic lime, bringing gaseous wastes from burning limestone into contact with water to obtain carbonic acid. Limestone is burnt using heat obtained from burning part of the volume of acetylene, obtained from part of the volume of calcium carbide. At least part of the obtained acetylene is used in synthesis of ethanol and/or dichloroethane and/or ethyleneglycol and/or acetone. During synthesis of ethanol and/or dichloroethane, acetylene is reacted with hydrogen in the presence of palladium as catalyst, after which at least part of synthesised C2H4 material is reacted with water vapour, obtaining ethanol, and/or reacted with chlorine, obtaining dichloroethane. Also at least part of the obtained acetylene is subjected to hydrolysis, obtaining ethyleneglycol. Also during synthesis of acetone, part of the obtained acetylene is reacted with water vapour, where the hydrogen obtained is used in said synthesis of ethanol and/or dichloroethane and/or burnt in the burning process. Carbon dioxide obtained from synthesis of acetone is used in the process of producing carbonic acid.
EFFECT: wide range of obtained finished products and prevention of formation of industrial wastes.
4 cl, 1 ex, 1 dwg
FIELD: production processes.
SUBSTANCE: there proposed is the method of device cleaning from deposits formed as a result of purified N-methylpyrrolidone regeneration by N-methylpyrrolidone distillation from material flow of contaminated N-methylpyrrolidone. Contaminated N-methylpyrrolidone is formed according to the method of extractive separation of acetylene from reaction mixture of partial hydrocarbon oxidation after distillation of gaseous acetylene. Note that hot water is supplied to the device and mixed.
EFFECT: proposed method permits to exclude manual operation with solid substances, but at the same time regenerating significant part of purified contaminated N-methylpyrrolidone.
9 cl, 1 dwg, 2 ex
FIELD: inorganic compounds technologies.
SUBSTANCE: invention is directed to production of acetylene and lime through hydrolysis of calcium carbide. Hydrolysis solution is prepared from water/ethanol mixture containing at least 68 wt % ethanol. After hydrolysis, ethanol vapors are condensed to give anhydrous ethanol. Acetylene and lime are also obtained in anhydrous form.
EFFECT: enhanced process efficiency due to wastelessness of the process and possibility of using carbide dust and fines, improved safety of process, and improved quality of generated acetylene.
1 dwg, 2 ex
FIELD: chemical industry branches, possibly manufacture of calcium carbide, calcium oxide, acetylene, carbonic acid and slaked lime.
SUBSTANCE: coal-carbonate mineral raw material - lime is fired in reactor 1 with use of acetylene as high-temperature energy carrier. Lime produced in reactor 1 is fed to user and(or) to second reactor 2 and adding coke or coal with fraction size 20 -25 mm and with sulfur content less than 1% into reactor 2. Some part of acetylene further produced is also added to reactor 2. Ready calcium carbide is removed out of reactor 2 and it is fed to user and(or) to fourth reactor 4 where after contact with water acetylene and slaked lime are formed. Acetylene is fed through pipeline 15 to user and(or) to reactors 1 and 2. Ready slaked lime is fed to user. Gaseous products such as carbon dioxide from reactor 1 and carbon oxide from reactor 2 are fed to third reactor 3 where after contact with water carbonic acid is formed and fed to user as "dry ice" or in liquefied state.
EFFECT: possibility for producing wide assortment of commercial products in one waste-free cycle, elimination of environment contamination.
2 cl, 1 dwg
FIELD: oxidation catalysts.
SUBSTANCE: invention relates to carbon monoxide oxidation catalysts suitable to remove it from emission gases. Use of cadmium telluride as carbon monoxide oxidation catalyst is described.
EFFECT: interaction activity and selectivity of catalyst.