A process for the catalytic production of olefins and alcohols from propane

Abstract

The application provides a method for catalyzing propane to produce olefins and alcohols, and relates to the technical field of chemical industry.The method for catalyzing propane to produce olefins and alcohols is used for preparing olefins and alcohols from propane under the conditions of heating and thermal radiation;the heating source can generate thermal radiation while providing temperature;the thermal radiation also has a catalytic effect;thermal radiation catalysis is mainly divided into two parts, i.e., heat energy transmission of thermal radiation and a thermal radiation spectrum which can be used for driving photocatalysis to achieve the effect of photo-thermal synergistic catalysis;and the catalyst which can absorb the spectrum of thermal radiation is added in the method to increase the surface temperature of the catalyst and improve the internal energy of the reaction system, so that the reaction rate is accelerated.The method has the characteristics of simple operation and stable operation, and the existing industrial equipment does not need to be modified too much;the product not only has olefins, but also can produce alcohol substances, and the product value of propane conversion is effectively increased.

Description

TECHNICAL FIELD

[0001] The application relates to the chemical technology field, in particular to a method for catalytically preparing olefins and alcohols from propane. BACKGROUND

[0002] China is rich in propane reserves, and in recent years, the development of shale gas has further increased the production of propane. At present, the utilization of propane in China is mostly in the form of combustion for energy supply, which greatly reduces its utilization value. Converting propane into high-value-added products is one of the key technologies for improving the utilization efficiency of propane and realizing efficient utilization of carbon-based energy, and has broad practical prospects and huge economic benefits.

[0003] Among the downstream products of propane, propylene is a very important chemical raw material, which can be used to produce high-value-added products such as polypropylene, acrylonitrile, propylene oxide, ethylene-propylene rubber, nylon 66 and ABS resin. However, in the existing propane dehydrogenation process to produce propylene, a catalyst regeneration process is required, which is complicated to operate, and in addition to propylene, which is a high-value-added product, no other high-value-added product is produced. SUMMARY

[0004] The purpose of the present application is to provide a method for catalytically preparing olefins and alcohols from propane, to solve the problem that the existing propane dehydrogenation process to produce propylene requires a catalyst regeneration process, which is complicated to operate, and the product is single.

[0005] To achieve the above purpose, the following technical solutions are adopted in the present application:

[0006] The present application provides a method for catalytically preparing olefins and alcohols from propane, in which propane is introduced into a reaction device, and olefins and alcohols are prepared by catalysis under heating and thermal radiation conditions; the thermal radiation includes first thermal radiation generated by the heat source of the heating; a catalyst is also added to the reaction device, which can absorb the spectrum of the thermal radiation to increase the surface temperature of the catalyst and increase the internal energy of the reaction system; the catalyst includes any one or more of gaseous catalysts, solid catalysts and liquid catalysts.

[0007] The heat source for heating not only provides temperature, but also performs thermal radiation, which can generate thermal radiation spectrum and also has a catalytic effect. Thermal radiation catalysis mainly includes two parts: one is the transfer of thermal energy by thermal radiation, and the other is that the thermal radiation spectrum can be used to drive photocatalysis to achieve the effect of photo-thermal synergistic catalysis.

[0008] The thermal radiation refers to the phenomenon that an object radiates electromagnetic waves due to having a temperature, and is one of three ways of heat transfer. An object with a temperature higher than absolute zero can produce thermal radiation. The higher the temperature, the greater the total energy radiated and the more short-wave components. The spectrum of thermal radiation is a continuous spectrum, and the wavelength coverage theoretically ranges from 0 to ∞. Generally, thermal radiation mainly includes visible light and infrared radiation with longer wavelengths. Therefore, the heat source for heating can also produce thermal radiation, i.e., first thermal radiation, which serves as one of the conditions of the method for catalytically producing olefins and alcohols from propane.

[0009] In addition to heating and thermal radiation, the method for catalytically producing olefins and alcohols from propane also requires the addition of a catalyst to improve the catalytic rate. The catalyst has the property of absorbing the spectrum produced by thermal radiation, thereby increasing the surface temperature and vibration of the catalyst, promoting the activation of reaction gas molecules, and thus accelerating the reaction rate.

[0010] The specific form of the catalyst is not limited, and can be a gas (a substance with a gasification temperature lower than the catalytic temperature) or a liquid (a substance with a melting temperature lower than the catalytic temperature) that has the ability to absorb the spectrum of thermal radiation, as well as a solid catalyst.

[0011] The method for catalytically producing olefins and alcohols from propane can generate olefins and alcohols under the action of heating, thermal radiation, and a catalyst. The alcohols can be methanol or ethanol, or a mixture of methanol and ethanol, effectively increasing the product value of propane conversion.

[0012] Preferably, the heating temperature of the propane is 400-700°C, for example, 400-500°C, 500-600°C, or 600-700°C, and more specifically, for example, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C, or 700°C.

[0013] In a preferred embodiment, a radiation source is further arranged in the reaction device, and the thermal radiation further includes second thermal radiation generated by the radiation source. By adding an external radiation source to the heat source, the catalytic reaction efficiency can be improved. The radiation source can be the same as or different from the heat source.

[0014] Preferably, the temperature of the radiation source is 500-1000°C, for example, 500-700°C, 600-800°C, or 800-1000°C, and more specifically, for example, 500°C, 550°C, 600°C, 650°C, 700°C, 750°C, 800°C, 850°C, 900°C, or 1000°C.

[0015] Preferably, when the heating temperature of the propane is 400-450°C, the propane is catalytically prepared to obtain olefins and methanol.

[0016] When the heating temperature of the propane is 450-700℃, the propane is catalytically prepared to obtain olefins and ethanol.

[0017] The reaction temperature of methanol is lower than that of ethanol, ethanol is more stable than methanol, and ethanol can react at a higher temperature.

[0018] Preferably, the catalyst comprises a gas catalyst, which is a gas molecule with strong spectral absorption of thermal radiation; the gas catalyst molecule itself has increased internal energy, which is conducive to the transfer of kinetic energy during molecular collision.

[0019] Preferably, the gas catalyst includes any one or two of methane, carbon dioxide and water vapor, and other gas molecules that can absorb the spectrum of thermal radiation.

[0020] More preferably, the gas catalyst is water vapor, which has strong absorption in the infrared region, and the absorption of propane in the infrared region can promote the activation of propane, and the activated propane is catalyzed by water molecules to produce methanol / ethanol and olefins.

[0021] Preferably, the volume ratio of the propane to the gas catalyst is (1000:1)-(1:1000), for example, it can be (500:1)-(1:1000), or (1000:1)-(1:100), or (100:1)-(1:1);

[0022] More preferably, the volume ratio of the propane to the gas catalyst is (100:1)-(1:1);

[0023] More preferably, the volume ratio of the propane to the gas catalyst is (50:1)-(1:1), for example, it can be 2:1, 3:2, 5:3, 10:1, 50:2.6 or 50:23, etc.

[0024] Preferably, the reaction device is a tubular reactor, and the propane is introduced into the reaction tube of the reaction device, and the reaction tube is made of transparent high-temperature resistant material or high-emissivity material;

[0025] Or the reaction device is a cavity type reactor, and the propane is introduced into the reaction cavity of the reaction device, and the heat source directly heats and radiates the propane.

[0026] Please refer to Figure 1 and Figure 2, the reaction device is a tubular reactor, comprising a shell 40, propane is introduced into the reaction tube 10 of the reaction device through the gas inlet 11, and is communicated with the detection equipment through the gas outlet 12, the reaction tube 10 is prepared from transparent high-temperature-resistant material or high-radiation material. The transparent high-temperature-resistant material for preparing the reaction tube can be transparent quartz, so that a transparent quartz tube is prepared; the high-radiation material for preparing the reaction tube can be corundum, ceramic, sandblasted stainless steel tube or steel tube sprayed with blackbody radiation paint, etc.

[0027] Preferably, please continue to refer to Figure 1 and Figure 2 When the reaction device is a tubular reactor, the reaction device is also provided with a cavity 30, and the reaction tube is arranged in the cavity 30; the heat source 20 and the radiation source are also installed in the structure of the cavity 30, so as to facilitate the release of heat radiation.

[0028] Preferably, the distance between the radiation source and the heat source and the reaction tube is independently 0-100 cm.

[0029] The distance between the heat source 20 and the reaction tube 10 can be 0-100 cm, for example, it can be 0 cm, 5 cm, 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, 35 cm, 40 cm, 45 cm, 50 cm, 55 cm, 60 cm, 65 cm, 70 cm, 75 cm, 80 cm, 85 cm, 90 cm, 95 cm or 100 cm, or any value between 0-100 cm. The installation distance determines the temperature and heat radiation spectrum of the reaction tube 10, so the installation distance can be adjusted according to the required temperature and heat radiation spectrum in actual application. Among them, the closer the heat source 20 and the reaction tube 10, the more conducive to the transmission of heat radiation, which is convenient for the catalyst or propane molecules to absorb the heat radiation spectrum.

[0030] Preferably, the radiation source is a wound heating wire or a heating rod, and the heat source is a wound heating wire (as shown in Figure 1 ) or a heating rod (as shown in Figure 2 ); the material of the radiation source is metal, and the emissivity of the metal is between 0.5 and 0.99. The emissivity, also called the specific radiation, is the ratio of the radiation capacity of an object to the radiation capacity of a black body at the same temperature, which is called the emissivity of the object. Generally, it is in the range of [0, 1], and the higher the emissivity, the higher the heat radiation of the object. Preferably, the material of the radiation source is nickel-chromium alloy.

[0031] Preferably, the outer surface of the heat source is wrapped with corundum and / or ceramic; corundum and ceramic are high-radiation materials, which can improve the emissivity of the heat source, or the heat source also adopts a high-emissivity metal material.

[0032] Preferably, the flow rate of the propane is 1-1000 ml / min, for example, it can be 1-100 ml / min, or 100-300 ml / min, or 300-500 ml / min, or 500-1000 ml / min; the flow rate of the propane is determined according to the reaction amount required by the actual process.

[0033] Preferably, the flow rate of the propane is 1-100 ml / min;

[0034] Preferably, the flow rate of the propane is 1-50 ml / min, for example, it can be (1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30 or 50) ml / min.

[0035] Compared with the prior art, the beneficial effects of the present application include:

[0036] The method for catalytically producing olefins and alcohols from propane provided by the present application catalytically produces olefins and alcohols from propane under heating and thermal radiation conditions. The heating source not only provides temperature, but also generates thermal radiation, which also has a catalytic effect. Thermal radiation catalysis mainly includes two parts: thermal radiation transmits heat energy, and the spectrum of thermal radiation can be used to drive photocatalysis, achieving the effect of synergistic photocatalysis. In addition, a catalyst that can absorb the spectrum of thermal radiation is added in the method to increase the surface temperature of the catalyst and increase the internal energy of the reaction system, thereby accelerating the reaction rate. The method has the characteristics of simple operation and stable operation, and does not require excessive modification of existing industrial equipment. The product not only includes olefins, but also includes alcohol substances, effectively increasing the product value of propane conversion. BRIEF DESCRIPTION OF DRAWINGS

[0037] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope of the present application.

[0038] Figure 1 The structure schematic diagram of an embodiment of the reaction device of the present application;

[0039] Figure 2 The structure schematic diagram of another embodiment of the reaction device of the present application.

[0040] The reference signs are:

[0041] 10 - reaction tube; 11 - gas inlet; 12 - gas outlet; 20 - heat source; 30 - cavity; 40 - shell. DETAILED DESCRIPTION

[0042] The embodiments of the present application will be described in detail below with specific examples, but those skilled in the art will understand that the following examples are only for illustration of the present application, and should not be regarded as limiting the scope of the present application. The specific conditions are not specified in the examples, and the conventional conditions or the conditions recommended by the manufacturer are used. The reagents or instruments used are not specified by the manufacturer, and are conventional products that can be purchased on the market.

[0043] For the convenience of description, the reaction device used in the method for catalytically producing olefins and alcohols from propane in the embodiments of the present application is illustrated by taking a similar tubular reactor as an example. Figure 2 The similar tubular reactor is illustrated by taking a transparent quartz tube as a reaction tube 10, and a high-heat-radiation alumina-based electric heating rod as a heat source 20. There are totally 6 heating rods, and the distance between the heating rods and the reaction tube 10 is about 5 cm. Figure 2 The difference is that the heat source 20 is uniformly installed in parallel around the four walls of the reaction tube 10. The radiation source is a spiral-wound metal wire with a length of 14.5 cm and made of nickel-chromium alloy. The metal wire is installed in parallel between the reaction tube 10 at a distance of about 5 cm.

[0044] Example 1

[0045] A method for catalytically producing olefins and alcohols from propane, the specific steps are as follows:

[0046] After mixing the reaction gas according to the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 400°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 is introduced. After 1 hour of reaction, the initial conversion rate of the reaction is about 4.55%, and the olefin selectivity is 80.50% according to the results of the external gas chromatography.

[0047] Example 2

[0048] A method for catalytically producing olefins and alcohols from propane, the specific steps are as follows:

[0049] After mixing the reaction gas according to the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 450°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 is introduced. After 1 hour of reaction, the initial conversion rate of the reaction is about 4.61%, the olefin selectivity is 83.24%, and the methanol production rate is 0.074 μmol / h according to the results of the external gas chromatography.

[0050] Example 3

[0051] A method for catalytically producing olefins and alcohols from propane, the specific steps are as follows:

[0052] The reaction gas is mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 500°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 is used. After 1 hour of reaction, the initial conversion rate is about 6.24%, and the olefin selectivity is 84.36% according to the external gas chromatography results.

[0053] Example 4

[0054] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0055] The reaction gas is mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 550°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 is used. After 1 hour of reaction, the initial conversion rate is about 10.29%, and the olefin selectivity is 78.66% according to the external gas chromatography results.

[0056] Example 5

[0057] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0058] The reaction gas is mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 600°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 is used. After 1 hour of reaction, the initial conversion rate is about 23.51%, and the olefin selectivity is 79.31% according to the external gas chromatography results.

[0059] Example 6

[0060] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0061] The reaction gas is mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 650°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 is used. After 1 hour of reaction, the initial conversion rate is about 55.44%, the olefin selectivity is 75.30%, and the ethanol production rate is 0.037 μmol / h according to the external gas chromatography results.

[0062] Example 7

[0063] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0064] The reaction gas was mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature was set to 400°C, the thermal radiation temperature was set to 650°C, the total reaction gas flow rate was set to 2 mL / min, and the reaction gas was introduced into the reaction device as shown in Figure 1 After 1 hour of reaction, the initial conversion rate was about 5.99%, the olefin selectivity was 82.37%, and the methanol production rate was 0.086 μmol / h, according to the results of the external gas chromatography.

[0065] Example 8

[0066] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0067] The reaction gas was mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature was set to 450°C, the thermal radiation temperature was set to 650°C, the total reaction gas flow rate was set to 2 mL / min, and the reaction gas was introduced into the reaction device as shown in Figure 1 After 1 hour of reaction, the initial conversion rate was about 6.38%, the olefin selectivity was 82.50%, the methanol production rate was 0.185 μmol / h, and the ethanol production rate was 0.012 μmol / h, according to the results of the external gas chromatography.

[0068] Example 9

[0069] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0070] The reaction gas was mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature was set to 500°C, the thermal radiation temperature was set to 650°C, the total reaction gas flow rate was set to 2 mL / min, and the reaction gas was introduced into the reaction device as shown in Figure 1 After 1 hour of reaction, the initial conversion rate was about 6.52%, the olefin selectivity was 83.39%, and the ethanol production rate was 0.023 μmol / h, according to the results of the external gas chromatography.

[0071] Example 10

[0072] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0073] The reaction gas was mixed in the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature was set to 550°C, the thermal radiation temperature was set to 650°C, the total reaction gas flow rate was set to 2 mL / min, and the reaction gas was introduced into the reaction device as shown in Figure 1 After 1 hour of reaction, the initial conversion rate was about 23.30%, the olefin selectivity was 84.58%, and the ethanol production rate was 0.031 μmol / h, according to the results of the external gas chromatography.

[0074] Example 11

[0075] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0076] After mixing the reaction gas according to the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 600°C, the thermal radiation temperature is set to 650°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 After 1 hour of reaction, the initial conversion rate of the reaction is about 44.35%, the olefin selectivity is 84.98%, and the ethanol production rate is 0.039 μmol / h, according to the external gas chromatography results.

[0077] Example 12

[0078] A method for catalyzing propane to produce olefins and alcohols, the specific steps are as follows:

[0079] After mixing the reaction gas according to the ratio of propane 50%, Ar 47.4%, and water gas 2.6%, the reaction temperature is set to 650°C, the thermal radiation temperature is set to 650°C, the total reaction gas flow rate is set to 2 mL / min, and the reaction device as shown in Figure 1 After 1 hour of reaction, the initial conversion rate of the reaction is about 63.10%, the olefin selectivity is 78.06%, and the ethanol production rate is 0.055 μmol / h, according to the external gas chromatography results.

[0080] Table 1 is the experimental results of the method for catalyzing propane to produce olefins and alcohols in Examples 1 to 12, according to Table 1, the method of the present application can catalyze propane to produce olefins and methanol at 450°C, and can catalyze propane to produce olefins and ethanol at 650°C without an external radiation source; and after the external radiation source, due to the increase in thermal radiation efficiency, propane can be catalyzed to produce olefins and methanol at 400°C and 450°C, and propane can be catalyzed to produce olefins and ethanol at 450°C.

[0081] Table 1 Experimental results of the method for catalyzing propane to produce olefins and alcohols in Examples 1 to 12

[0082]

[0083] Finally, it should be noted that the above-described embodiments are merely intended for describing and illustrating, but not limiting the technical solutions of the present application; even though the present application has been described in detail with reference to the above embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the above embodiments, or equivalently replace some or all of the technical features thereof; and such modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

[0084] Furthermore, those skilled in the art will appreciate that a combination of features from different embodiments can be meant to be within the scope of the present application and form a different embodiment, although some embodiments herein include certain features rather than others included in other embodiments. For example, in the claims above, any of the claimed embodiments can be used in any combination. The information disclosed in this Background section is intended only to enhance an understanding of the general background of the present application, and should not be taken as an acknowledgement or any form of suggestion that this information forms a prior art that is already publicly known.

Claims

1. A method for catalytically producing olefins and alcohols from propane, characterized in that, Propane is introduced into a reaction apparatus, and the propane is catalytically used to prepare olefins and alcohols under heating and thermal radiation conditions; the thermal radiation includes first thermal radiation generated by the heat source; a catalyst is also added to the reaction apparatus, which can absorb the spectrum of the thermal radiation to increase the surface temperature of the catalyst and improve the internal energy of the reaction system; the catalyst is water vapor. The propane is heated at a temperature of 400~700℃; The reaction device is also equipped with a radiation source, and the thermal radiation also includes a second thermal radiation generated by the radiation source; The temperature of the radiation source is 500~1000℃; The radiation source is a wound heating wire or heating rod, and the heat source is a wound heating wire or heating rod; the material of the radiation source is metal, and the emissivity of the metal is between 0.5 and 0.

99. The outer surface of the heat source is coated with corundum and / or ceramic. The radiation source is made of nickel-chromium alloy; The reaction device is a tubular reactor, and the propane is introduced into the reaction tube of the reaction device. The reaction tube is made of transparent high-temperature resistant material. The reaction device is also provided with a cavity, and the reaction tube is disposed in the cavity.

2. The method for catalytic propane production of olefins and alcohols according to claim 1, characterized in that, When the propane is heated to a temperature of 400-450°C, the propane is used to catalytically prepare olefins and methanol. When the propane is heated to a temperature of 450~700℃, the propane is used to catalytically prepare olefins and ethanol.

3. The method for catalytic propane production of olefins and alcohols according to claim 1, characterized in that, The volume ratio of propane to water vapor is (1000:1) to (1:1000).

4. The method for catalytic propane production of olefins and alcohols according to claim 3, characterized in that, The volume ratio of propane to water vapor is (100:1) to (1:1).

5. The method for catalytic propane production of olefins and alcohols according to claim 4, characterized in that, The volume ratio of propane to water vapor is (50:1) to (1:1).

6. The method for catalytic propane production of olefins and alcohols according to claim 1, characterized in that, The distances between the radiation source and the heat source and the reaction tube are independently 0-100cm.

7. The method for catalytic propane production of olefins and alcohols according to claim 1, characterized in that, The propane flow rate is 1-1000 ml / min.

8. The method for catalytic propane production of olefins and alcohols according to claim 7, characterized in that, The flow rate of propane is 1-100 ml / min.

9. The method for catalytic production of olefins and alcohols from propane according to claim 8, characterized in that, The propane flow rate is 1-50 ml / min.

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