JP5986477B2 - Paraffin manufacturing method and manufacturing apparatus - Google Patents

Description

  The present invention relates to a method and apparatus for producing paraffins such as ethane and propane from olefins such as ethylene and propylene.

  Among paraffins (saturated chain hydrocarbons), ethane and propane can be obtained by fractionating petroleum. However, as a demand field, ethane is used as a raw material for ethylene and chloroethylene and as a cryogenic coolant. Propane is often used as a gas fuel as LPG, but recently it has also been used in the field of electronic materials such as semiconductors, and for such applications, particularly high-purity propane is required. . For example, the concentration of each impurity in high-purity propane is required to be less than 1 ppm.

  Producing paraffins such as high-purity ethane and propane can be achieved by cracking crude oil and performing precise distillation at the stage of fractional distillation, but it is necessary to set precise distillation conditions and increase costs. Invite On the other hand, ethane is mainly used as a raw material for petroleum products such as ethylene and chloroethylene, and propane is mainly used as a gas fuel. In such applications, high-purity ethane and propane are not required. Therefore, because of the high-purity paraffin with a low demand, such an unprofitable refining is not performed in refineries as industrial products.

  The raw material gas mainly composed of propane used as a high-purity raw material contains, for example, methane, ethane, propylene, isobutane, normal butane, and the like as impurities. A method for achieving high purity by removing these impurities Has been proposed (see, for example, Patent Documents 1 and 2).

  Patent Document 1 proposes a technique for recovering high-purity propane from low-purity propane by adsorbing and removing ethane, propylene, isobutane, normal butane, etc. preferentially over propane using molecular sieve or activated carbon as an adsorbent. Patent Document 2 proposes a method for purifying paraffin (including propane) from a raw material containing paraffin (including propane) having 2 to 6 carbon atoms and olefin (including propylene) having 2 to 6 carbon atoms, and silver. A technique has been proposed in which olefins are preferentially absorbed in an ion absorbing solution and paraffin that has not been absorbed in the absorbing solution is recovered and purified. In both methods of Patent Documents 1 and 2, impurities other than propane are removed by performing an adsorption operation and an absorption operation, and a part of propane is lost together with the impurities, so propane is recovered at a high recovery rate. I can't do it.

  On the other hand, Patent Document 3 proposes a technique for producing propane by a reaction operation by adding hydrogen to liquid phase propylene, and the recovery rate does not decrease. However, since the temperature rises due to an exothermic reaction, the reaction operation cannot be performed with a high concentration of propylene, and the 25% concentration is the limit. Also, two catalyst tanks filled with nickel catalyst are used, one of which is a catalyst replacement or regeneration spare, and the propylene propanation reaction is substantially carried out in one catalyst tank. Has been.

JP 2012-25729 A Reissue WO2010 / 074019 US3509226A specification

  The present invention has been conceived under such circumstances, and a method and apparatus capable of substantially completely paraffinizing a paraffin by reducing a high concentration olefin with hydrogen. It is an issue to provide.

  The method for producing paraffin provided by the first aspect of the present invention is a method for producing paraffin from an olefin and hydrogen in a gas phase by a reduction reaction that proceeds in the presence of a reduction catalyst, each of which is described above. A plurality of catalyst tanks filled with a reduction catalyst are provided in series along a mainstream line through which hydrogen flows, and the mainstream line is arranged so that the amount of hydrogen in the gas introduced into each catalyst tank is greater than the amount of olefins. On the other hand, the olefin is dividedly added.

When the olefin is reduced with hydrogen, the temperature rises due to the exothermic reaction. For example, in the case of ethylene and propylene, the reaction is exothermic and is as follows.
C ₂ H ₄ + H ₂ = C ₂ H ₆ + ΔH ΔH = −136.27 kJ / mol C ₃ H ₆ + H ₂ = C ₃ H ₈ + ΔH ΔH = −124.7 kJ / mol

Therefore, when this reaction is carried out with liquid phase pure olefin, the olefin molecules are close to each other, so the calorific value per unit volume of the olefin increases, and the exothermic reaction takes place at a high speed and the cooling rate cannot catch up. As a result, in the prior art, 25% concentration was the limit as a liquid phase olefin as a raw material as in Patent Document 3. In order to solve this problem, in the present invention, the intermolecular distance is increased by reacting in the gas phase, the amount of reaction per unit volume of olefin is reduced, and the calorific value is reduced. For example, the mass per mole of propylene is 42.08 g from the molecular weight, and the number of molecules is 6 × 10 ²³ in terms of Avogadro's number. Since the specific gravity of the liquid is 0.6139 g / cm ³ , the space occupied by one molecule in the liquid phase is 11.42 × 10 ⁻²³ cm ³ . On the other hand, in the gas phase, the volume occupied by 1 mol at 1 atm and 0 ° C. is 22.4 L, so the space occupied by one molecule is 3.733 × 10 ⁻²⁰ cm ³ . Therefore, when the liquid phase is changed to the gas phase, the intermolecular distance is about 330 times as large as the space occupied by one molecule, so the intermolecular distance is 6.9 times longer. Accordingly, the reduction reaction of propylene is an exothermic reaction, and the longer the intermolecular distance, the easier the heat removal or heat removal by heat transfer. Therefore, the reduction reaction is preferably performed in the gas phase.

  In this method, the catalyst tank is further divided and installed in series in at least two tanks, and olefin is divided and added to each catalyst tank using hydrogen as the main stream. The reduction reaction of olefin with hydrogen becomes easier to proceed by adding more hydrogen than the theoretical equivalent. Therefore, the catalyst tank is divided into two or more tanks in series, and olefin (ethylene or propylene) is divided and added with hydrogen as the main stream, so that the hydrogen amount / olefin amount (molar ratio) in each catalyst tank is further increased. The reduction reaction can be promoted. Furthermore, since the olefin (ethylene or propylene) is added in two or more parts, the increase in the reaction temperature per catalyst tank can be reduced. Here, the mainstream hydrogen purity is 99 to 99.99999 mol%, preferably 99.999 mol% or more.

  In a preferred embodiment, the ratio of the amount of hydrogen and the amount of olefin in the gas introduced into each catalyst tank is such that the amount of hydrogen / the amount of olefin (molar ratio) is 1.1 or more.

  In a preferred embodiment, the amount of olefin in the gas introduced into each of the plurality of catalyst tanks is equal.

  When the amount of olefin added to hydrogen, which is the mainstream, is made to be a molar ratio so that the hydrogen amount / olefin amount is 1.1 or more and the number of divisions of the catalyst tank is increased, The hydrogen / olefin molar ratio can be made higher and the total mixing molar ratio can be as close to 1.0 as possible. As the hydrogen / olefin molar ratio decreases, the olefin reduction reaction becomes difficult to proceed, so that the hydrogen / olefin molar ratio is 1.1 or more at any point, while the reduction reaction is facilitated. preferable. And how much the amount of residual hydrogen in the paraffin produced after the reduction reaction can be reduced depends on how many catalyst tanks are installed.

  In a preferred embodiment, the reduction reaction is performed at an internal temperature of 100 ° C. or lower.

  If the reaction temperature is too high during the reduction reaction or if the amount of hydrogen to be added is small, the olefin is decomposed and methane and ethane are produced as impurities, so the reaction temperature is 100 ° C. or lower, preferably 50 ° C. or lower. For this purpose, for example, the catalyst tank is forcibly cooled from the outside using chiller water or the like. If the temperature is too low, the olefin liquefies and the reduction reaction is difficult to proceed. Therefore, when the operating pressure is 0.3 MPaG, it is necessary to set the temperature to −76.3 ° C. or higher for ethylene and −12.0 ° C. or higher for propylene. . The pressure during the reduction reaction is usually 0.0 to 0.5 MPaG. When the pressure is increased, the reduction reaction is accelerated, but the reaction temperature rises due to the reaction heat. Also, it is not preferable to increase the pressure during the reduction reaction because the olefin is liquefied to form a liquid phase reaction.

  In a preferred embodiment, the reduction catalyst filled in the catalyst tank includes a product obtained by diluting a catalytically active substance having catalytic activity with a diluent medium having no catalytic activity, and mixing the diluent medium. The ratio is gradually reduced from the upstream side to the downstream side of the catalyst tank.

  According to such a configuration, heat generated by the reduction reaction is transmitted to the dilution medium, and is dispersed and easily removed from the outside. On the other hand, since the mixing ratio of the dilution medium is decreased from the upstream side to the downstream side of the catalyst tank, the number of active points of the catalyst increases toward the downstream side. For this reason, it is prevented that the olefin flowing through the catalyst tank slips through unreacted, and high purity paraffin is obtained.

  In addition, when the reduction reaction is performed, the heat generation amount increases as the amount of the processing gas per unit cross-sectional area increases, and the decomposition reaction to methane and ethane, which are impurities, easily proceeds, and the concentration of impurities increases. . For this reason, the smaller the gas flow rate or space velocity, the better results. For example, the space velocity SV based on the standard condition is 1000 / h or less including the dilution medium, and preferably 500 / h or less. On the other hand, if the space velocity is too large, the olefin does not sufficiently change to paraffin and unreacted olefin remains.

  In a preferred embodiment, the dilution medium includes a carrier that supports the catalytically active substance.

  In a preferred embodiment, the catalytically active substance is made of a metal containing at least one selected from palladium, rhodium, platinum, ruthenium, and nickel.

  In a preferred embodiment, the dilution medium includes an inorganic filler.

  In a preferred embodiment, the olefin has 2 to 4 carbon atoms, and the paraffin has 2 to 4 carbon atoms.

  An apparatus for producing paraffin provided by the second aspect of the present invention is an apparatus for producing paraffin from a olefin and hydrogen in a gas phase by a reduction reaction that proceeds in the presence of a reduction catalyst. A plurality of catalyst tanks that are provided in series along the mainstream line, each having a gas introduction part and a gas outlet part, and containing the reduction catalyst, and hydrogen in the mainstream line. And a plurality of branch lines connected to the mainstream line upstream of the gas introduction part of each catalyst tank, and the olefin is added through the plurality of branch lines. And an olefin addition means.

  In preferable embodiment, the number of installation of the said catalyst tank is the range of 2-5.

  In a preferred embodiment, a temperature adjusting means for adjusting the internal temperature of the catalyst tank is provided.

  In a preferred embodiment, the reduction catalyst filled in the catalyst tank has a plurality of catalytic active substances having catalytic activity diluted with a diluent medium having no catalytic activity, and the mixing ratios of the dilution media are different from each other. The catalyst region is configured to be included, and the mixing ratio of the dilution medium in the plurality of catalyst regions is gradually reduced from the upstream side to the downstream side in the catalyst tank.

  In preferable embodiment, the number of arrangement | positioning of the said catalyst area | region is the range of 2-5.

  In a preferred embodiment, the dilution medium includes a carrier that supports the catalytically active substance.

  In a preferred embodiment, the catalytically active substance is made of a metal containing at least one selected from palladium, rhodium, platinum, ruthenium, and nickel.

  In a preferred embodiment, the dilution medium includes an inorganic filler.

  In a preferred embodiment, a hydrogen removing unit is provided on the downstream side of the plurality of catalyst tanks in the mainstream line in order to remove hydrogen.

  In a preferred embodiment, the hydrogen removal means includes a pressure fluctuation adsorption gas separation device.

  In a preferred embodiment, the hydrogen removing means includes a partial reduction device.

  According to the paraffin manufacturing apparatus having such a configuration, the paraffin manufacturing method of the first aspect of the present invention can be appropriately performed.

  Other features and advantages of the present invention will become more apparent from the detailed description given below with reference to the accompanying drawings.

It is a schematic block diagram which shows the manufacturing apparatus of the paraffin which concerns on 1st Embodiment of this invention. It is a schematic block diagram which shows the manufacturing apparatus of the paraffin which concerns on 2nd Embodiment of this invention. It is a table | surface which shows the manufacture example of the propane when the number of installation of a catalyst tank is varied.

  Hereinafter, as a preferred embodiment of the present invention, a method for producing paraffin from olefin and hydrogen by a reduction reaction will be specifically described with reference to the drawings.

  FIG. 1 is a schematic configuration diagram showing an apparatus for producing paraffin according to a first embodiment of the present invention. The paraffin production apparatus X1 of the present embodiment is configured such that paraffin can be produced from the olefin and hydrogen in a gas phase state by the paraffin production method according to the present invention. The hydrogen cylinder 1, the olefin cylinder 2, Mainstream lines 21, 24, 26, a plurality of catalyst tanks 3, 4, an olefin line 22, and branch lines 23, 25 are provided. In this embodiment, the case where the olefin is propylene and the manufactured paraffin is propane will be described as an example.

  The hydrogen cylinder 1 is for supplying hydrogen to the mainstream line 21 and is filled with high-purity hydrogen gas under high pressure conditions.

  The main flow lines 21, 24, 26 receive hydrogen supplied from the hydrogen cylinder 1, propylene added via branch lines 23, 25 described later, and propane generated by a reduction reaction in the catalyst tanks 3, 4 described later. It is a flow line and is connected in series. The main flow line 21 is provided with a pressure reducing valve 11, a flow meter 12, and a valve 13.

  The catalyst tanks 3 and 4 are for generating paraffin (propane) from an olefin (propylene) and hydrogen by a reduction reaction that proceeds in the presence of a reduction catalyst, and are connected in series along mainstream lines 21, 24, and 26. Is provided.

  The catalyst tanks 3 and 4 have a sealed tubular structure, and gas inlets 3a and 4a are provided at one end and gas outlets 3b and 4b are provided at the other end. The catalyst tanks 3 and 4 are filled with a reduction catalyst. This reduction catalyst is for accelerating the reduction reaction of olefins with hydrogen.

  The reduction catalyst includes a catalytically active substance having catalytic activity diluted with a diluent medium. The catalytically active substance is made of a metal containing at least one selected from palladium, rhodium, platinum, ruthenium, and nickel, for example, palladium. In this embodiment, the catalytically active substance is supported by a carrier and is in the form of particles (catalyst particles), and the catalyst particles are diluted with an inorganic filler such as an alumina ball. The content ratio of palladium (catalytic active substance) in the catalyst particles is, for example, 0.1 to 1.0 wt%. Here, the carrier supporting the catalytically active substance and the inorganic filler correspond to the dilution medium referred to in the present invention.

  The reduction catalyst filled in the catalyst tank 3 includes a plurality (two in the present embodiment) of catalyst regions 301 and 302. In the present embodiment, the mixing ratio of the dilution medium (inorganic filler) in the catalyst regions 301 and 302 is different from each other, and is gradually decreased from the upstream side to the downstream side of the gas flow in the catalyst tank 3. ing. For example, for the catalyst region 301 located on the upstream side, the mixing ratio of the inorganic filler is 90 to 99% by volume, and for the catalyst region 302 located on the downstream side, the mixing ratio of the inorganic filler is 80 to 99%. 90% by volume.

  The reduction catalyst filled in the catalyst tank 4 includes a plurality (three in this embodiment) of catalyst regions 401, 402, and 403. The mixing ratios of the inorganic fillers in the catalyst regions 401, 402, and 403 are different from each other, and are decreased stepwise from the upstream side to the downstream side in the catalyst tank 4. For example, the mixing ratio of the inorganic filler is set to 90 to 99% by volume for the catalyst area 401 located on the most upstream side, and the mixing ratio of the inorganic filler is set to 80 to 99 for the catalyst area 402 positioned in the middle. 90% by volume, and the catalyst region 403 located on the most downstream side does not contain an inorganic filler (that is, the mixing ratio of the inorganic filler is 0% by volume), and consists only of the catalyst particles. .

  Jackets 32 and 42 are provided outside the catalyst tanks 3 and 4. The jackets 32 and 42 are for adjusting the internal temperature of the catalyst tanks 3 and 4, and are configured to surround the outer periphery of the catalyst tanks 3 and 4. Chiller water as a temperature adjusting medium (cooling medium) is supplied to the jackets 32 and 42 through the lines 33 and 43.

  The olefin cylinder 2 is for supplying the raw olefin gas to the olefin line 22, and the raw olefin gas is sealed under high pressure conditions. The olefin line 22 is provided with a pressure reducing valve 14.

  The branch lines 23 and 25 are for adding the raw material olefin gas to the mainstream lines 21 and 24, and one ends of the branch lines 23 and 25 communicate with the olefin line 22. The other end of the branch line 23 is connected to the mainstream line 21, and the other end of the branch line 25 is connected to the mainstream line 24. The branch line 23 is provided with a flow meter 15 and a valve 16. The branch line 25 is provided with a flow meter 17 and a valve 18.

  The main flow line 26 is provided with a pressure fluctuation adsorption gas separation device (PSA gas separation device) Y1 on the downstream side of the catalyst tanks 3 and 4. The PSA gas separation device Y1 is provided in the adsorption tanks 6A and 6B filled with an adsorbent 60 that preferentially adsorbs paraffin (propane), lines 61a to 61f leading to the adsorption tanks 6A and 6B, and these lines. The switching valves 62a to 62f are provided, and the gas separation operation by the pressure fluctuation adsorption gas separation method (PSA method) can be executed by appropriately switching the gas flow using the switching valves 62a to 62f. Is. For the adsorbent 60 filled in the adsorption tanks 6A and 6B, for example, zeolite or activated carbon can be employed.

  In the gas separation in the PSA gas separation device Y1, one cycle including, for example, an adsorption step and a desorption step is repeated in a single adsorption tank 6A (6B). In the adsorption step, the gas that has passed through the catalyst tank 4 is introduced into the adsorption tank 6A (6B) via the line 61a (61b) to adsorb the propane in the gas to the adsorbent 60, and hydrogen is concentrated from the adsorption tank. This is a process for deriving the non-adsorbed gas. The desorption step is a step for depressurizing the inside of the adsorption tank to desorb propane from the adsorbent 60 and lead out a desorption gas enriched with propane to the outside of the tower.

  A line 30 for flowing non-adsorbed gas is connected to the lines 61e and 61f. The line 30 is provided with a compressor 8, a cooler 9, and a buffer tank 10. The line 30 is provided with a valve 31, and the end of the line 30 is connected to the olefin line 22. A line 29 for flowing desorption gas is connected to the lines 61c and 61d, and a product tank 7 is provided at an end of the line 29.

[Propane production example with two catalyst tanks]
Next, a specific example of a method for producing paraffin (propane) from olefin (propylene) and hydrogen using the paraffin production apparatus X1 having the above configuration will be described.

  First, hydrogen gas (EG grade, manufactured by Sumitomo Seika Co., Ltd.) in the hydrogen cylinder 1 is supplied to the mainstream line 21 at a flow rate of 104.3 NL / h, for example, in a standard state quantity. The hydrogen gas in the mainstream line 21 is pressure-reduced to 0.3 MPaG by the pressure reducing valve 11, passes through the valve 13 while being monitored by the flow meter 12, and is introduced into the catalyst tank 3 through the gas inlet 3 a. .

  On the other hand, propylene gas (manufactured by Mitsui Chemicals, Inc.) as raw material olefin gas is supplied from the olefin cylinder 2 to the olefin line 22. The propylene gas contains 99.5 mol% of propylene and 0.5 mol% of propane as an impurity, and is supplied at a flow rate of 99.4 NL / h in a standard state. The propylene gas in the olefin line 22 is decompressed to 0.3 MPaG by the pressure reducing valve 14, and then 49.7 NL / h corresponding to 1/2 of the total flow rate 99.4 NL / h enters the branch line 23. , Passing through the valve 16 while being monitored by the flow meter 15, and added to the mainstream line 21. Propylene gas merged in the mainstream line 21 is introduced into the catalyst tank 3 through the gas inlet 3a.

The catalyst tank 3 has an inner diameter of 30.7 mm, and the total filling height of the catalyst regions 301 and 302 is 800 mm. In the catalyst region 301, catalyst particles having a particle diameter of 3 mm (N1182AZ, manufactured by JGC Catalysts & Chemicals Co., Ltd.) supported on alumina (Al ₂ O ₃ ) as a carrier with 0.5 wt% of palladium are 0.003 L. 0.293 L of alumina balls (manufactured by Sumitomo Chemical Co., Ltd., HD-2) having a diameter of 3 mm are mixed and filled with a total of 0.296 L, and the filling height is 400 mm. Further, in the catalyst region 302, 0.030L of the same catalyst particles as in the catalyst region 301 and 0.266L of alumina balls are mixed, and a total of 0.296L is filled, and the filling height is 400 mm.

  Regarding the gas G1 (hydrogen gas and propylene gas) introduced into the catalyst tank 3, the mixing ratio (molar ratio) of hydrogen and propylene is 104.3 / 49.7 = 2.1 for hydrogen gas / propylene gas, Hydrogen is in excess of propylene. The introduced gas G1 to the catalyst tank 3 passes through the catalyst regions 301 and 302 and is guided to the gas outlet 3b. Here, the space velocity SV of hydrogen gas and propylene gas passing through the catalyst regions 301 and 302 is (104.3 + 49.7) / (0.296 × 2) = 260 / h based on the standard state.

  In the catalyst regions 301 and 302, a reduction reaction that is an exothermic reaction proceeds by the action of the reduction catalyst. That is, propane is produced by a reduction reaction of propylene with hydrogen. In the reduction reaction, as understood from the chemical formula described in paragraph 0010, the number of moles of propylene consumed, the number of moles of hydrogen consumed, and the number of moles of propane produced are equal. Here, chiller water of 10 ° C. is supplied to the jacket 32 through the line 33 to cool the catalyst tank 3 from the outside, and the reaction temperature in the catalyst regions 301 and 302 is a predetermined temperature (about 20 ° C. or less) of 100 ° C. or less. ).

  In the reduction reaction of propylene (olefin) with hydrogen in the catalyst regions 301 and 302, since the catalytically active substance is diluted with the dilution medium, a local excessive temperature rise due to heat generated by the reduction reaction is prevented. Further, the internal temperature of the catalyst tank 3 can be adjusted more accurately by the flow of the cooling medium to the jacket 32. This contributes to preventing the generation of impurities due to the decomposition of the olefin occurring at a high temperature and promoting the reduction reaction. In the catalyst regions 301 and 302, all of the propylene in the introduced gas G1 becomes propane by a reduction reaction.

  As a result of the reduction reaction in the catalyst regions 301 and 302, the gas G2 derived from the gas outlet 3b has a hydrogen gas amount of 54.6 NL / h (104.3-49.7 = 54.6) and a propane gas amount. 49.7 NL / h, which is 104.3 NL / h in total. The gas G2 flows toward the next catalyst tank 4 through the mainstream line 24, and is introduced into the catalyst tank 4 through the gas inlet 4a.

  On the other hand, 49.7 NL / h corresponding to 1/2 of propylene gas (total flow rate 99.4 NL / h) in the olefin line 22 enters the branch line 25 and passes through the valve 18 while being monitored by the flow meter 17. And added to the mainstream line 24. The propylene gas merged in the main flow line 24 is introduced into the catalyst tank 4 through the gas inlet 4a.

  The catalyst tank 4 has an inner diameter of 30.7 mm as in the catalyst tank 3, while the total filling height of the catalyst regions 401, 402, and 403 is 900 mm. In the catalyst region 401, an alumina ball having a particle size of 3 mm and a catalyst particle having a particle size of 3 mm (same as the catalyst region 301 of the catalyst tank 3) on which alumina of 0.5 wt% palladium is supported is the same. The same as the catalyst region 301 of the catalyst tank 3 is mixed with 0.293 L, and a total of 0.296 L is filled, and the filling height is 400 mm. In the catalyst region 402, 0.030L of the same catalyst particles as in the catalyst region 401 and 0.266L of alumina balls having a particle diameter of 3mm are mixed to fill a total of 0.296L, and the filling height is 400mm. In the catalyst region 403, 0.074L is filled only with the same catalyst particles as the catalyst region 401, and the filling height is 100 mm.

  Regarding the gas G3 introduced into the catalyst tank 4, the mixing ratio (molar ratio) of hydrogen and propylene is 54.6 / 49.7 = 1.1 for hydrogen gas / propylene gas, and hydrogen is excessive with respect to propylene. It has become. The introduced gas G3 to the catalyst tank 4 passes through the catalyst regions 401, 402, 403 and is guided to the gas outlet 4b. Here, the space velocity SV of hydrogen gas and propylene gas passing through the catalyst regions 401, 402, 403 is (54.6 + 49.7) / (0.296 × 2 + 0.074) = 157 / h on the basis of the standard state. Become.

  In the catalyst regions 401, 402, and 403, a reduction reaction that is an exothermic reaction proceeds by the action of the reduction catalyst. That is, propane is produced by a reduction reaction of propylene with hydrogen. Here, chiller water of 10 ° C. is supplied to the jacket 42 through the line 43 to cool the catalyst tank 4 from the outside, and the reaction temperature in the catalyst regions 401, 402, 403 is a predetermined temperature (about 20 ° C.). It has been adjusted to be. In the catalyst regions 401, 402, and 403, all of the propylene in the introduced gas G3 becomes propane by the reduction reaction.

  As a result of the reduction reaction in the catalyst regions 401, 402, 403, the gas G4 led out from the gas outlet 4b has a hydrogen gas amount of 4.9 NL / h (54.6-49.7 = 4.9), and propane gas. The amount is 99.4 NL / h (49.7 + 49.7 = 99.4), for a total of 104.3 NL / h. The gas G4 flows toward the PSA gas separation device Y1 through the mainstream line 26.

  When the residual propylene concentration in the gas G4 (hereinafter referred to as “production gas” as appropriate) flowing through the mainstream line 26 was analyzed by gas chromatography, it was less than 1 ppm and less than the detection limit. In the reduction reaction in the entire two tanks of the catalyst tanks 3 and 4, the total mixing molar ratio of hydrogen / propylene is 104.3 / 99.4 = 1.05, and hydrogen is 4.7 mol% in the production gas. Remaining.

  Then, the production gas in the mainstream line 26 is sent to the PSA gas separation device Y1, and by performing the above-described gas separation operation, hydrogen as a non-adsorbed gas is led out from the adsorption tanks 6A and 6B and flows into the line 30. To do. The hydrogen flowing into the line 30 is compressed by the compressor 8, cooled by the cooler 9, and collected in the buffer tank 10. The recovered hydrogen passes from the buffer tank 10 through the valve 31 to the olefin line 22 and is recycled to the raw material system. On the other hand, in the gas separation operation in the PSA gas separation device Y1, propane from which hydrogen has been removed is led out from the adsorption tanks 6A and 6B as desorbed gas, and after passing through the line 29, high purity propane (product Gas).

  In the production of paraffin (propane) according to the present embodiment, by performing a reduction reaction from olefin and hydrogen in a gas phase state, the reaction amount per unit volume of olefin (propylene) is reduced, and the calorific value associated with the reduction reaction is reduced. Can be reduced. If the reaction temperature is too high when the reduction reaction of olefin (propylene) is performed, olefin decomposition occurs and impurities such as methane and ethane are generated. By using olefin gas as a raw material, a high concentration raw material olefin gas is produced. Even if the reaction is performed, an extreme temperature rise is avoided, and the raw olefin gas can be substantially completely paraffinized.

  In this production example, a plurality of catalyst tanks 3 and 4 are separated and installed in series, and olefin (propylene) is dividedly added to each of the catalyst tanks 3 and 4 using hydrogen as a main stream. The reduction reaction of olefin (propylene) with hydrogen becomes easier to proceed by adding more hydrogen than the theoretical equivalent. Therefore, by dividing the two catalyst tanks 3 and 4 in series and adding olefin (propylene) dividedly with hydrogen as the main stream, the hydrogen amount / olefin amount (molar ratio) in each catalyst tank 3 and 4 ) Can be made larger, and the reduction reaction can be promoted. Furthermore, since the olefin (propylene) is added in portions, an increase in the reaction temperature per each of the catalyst tanks 3 and 4 can be suppressed.

  The catalyst tanks 3 and 4 are adjusted so that the internal temperature becomes a predetermined temperature of 100 ° C. or less by chiller water flowing through jackets 32 and 42 provided outside. Thereby, the heat generated by the reduction reaction in the catalyst tanks 3 and 4 can be efficiently released to the outside, and the reduction reaction can be performed under an appropriate reaction temperature.

  The reduction catalysts (catalyst regions 301 and 302 and catalyst regions 401, 402, and 403) filled in the catalyst tanks 3 and 4 include a catalyst active material (catalyst particles) diluted with a diluent medium (inorganic filler). The mixing ratio of the inorganic filler is gradually reduced from the upstream side to the downstream side of the catalyst tanks 3 and 4. According to such a configuration, heat generated by the reduction reaction is transmitted to the inorganic filler, and is easily dispersed and removed from the outside. On the other hand, since the mixing ratio of the inorganic filler is decreased from the upstream side to the downstream side of the catalyst tank, the number of active points of the catalytically active substance increases toward the downstream side. For this reason, the olefin flowing through the catalyst tanks 3 and 4 is prevented from passing through unreacted, and a high purity paraffin is obtained.

  FIG. 2 is a schematic configuration diagram showing an apparatus for producing paraffin according to a second embodiment of the present invention. The paraffin production apparatus X2 of the present embodiment is the same as the paraffin production apparatus X1 shown in FIG. 1 with respect to the basic configuration, but the point that the number of catalyst tanks is three and the downstream side of the catalyst tank. It differs from the paraffin production apparatus X1 of the first embodiment in that a partial reduction apparatus for removing hydrogen is provided. In FIG. 2, the same or similar elements as those in the above embodiment are denoted by the same reference numerals as those in the above embodiment, and description thereof will be omitted as appropriate.

  The paraffin production apparatus X2 of this embodiment includes a hydrogen cylinder 1, an olefin cylinder 2, mainstream lines 21, 24, 26, 28, a plurality of catalyst tanks 3, 4, 5, an olefin line 22, and a branch line 23. , 25, 27. In this embodiment, the case where the olefin is propylene and the manufactured paraffin is propane will be described as an example.

  In this embodiment, the catalyst tank 5 is added compared with the said embodiment, and the branch line 27, the flow meter 19, the valve 20, and the mainstream line 28 are added with the addition of this catalyst tank 5. FIG.

  The catalyst tank 3 has the same configuration as the catalyst tanks 3 and 4, and a jacket 52 for flowing chiller water is provided outside. In the present embodiment, the reduction catalyst filled in the catalyst tank 4 includes two catalyst regions 401 and 402. For the catalyst region 401 located on the upstream side, the mixing ratio of the inorganic filler is 90 to 99% by volume, and for the catalyst region 402 located on the downstream side, the mixing ratio of the inorganic filler is 80 to 90% by volume. %.

  On the other hand, the reduction catalyst filled in the catalyst tank 5 includes three catalyst regions 501, 502, and 503. For the catalyst region 501 located on the most upstream side, the mixing ratio of the inorganic filler is 90 to 99% by volume, and for the catalyst region 502 located in the middle, the mixing ratio of the inorganic filler is 80 to 90% by volume. The catalyst region 503 located on the most downstream side does not contain an inorganic filler (that is, the mixing ratio of the inorganic filler is 0% by volume), and consists of only the catalyst particles.

  The mainstream line 28 is provided with a partial reduction device Y2 on the downstream side of the catalyst tanks 3, 4, and 5. The partial reduction device Y2 includes a condenser 601 through which gas from the mainstream line 28 passes, a line 602 for flowing cooling chiller water outside the condenser 601, and a U-shaped pipe 603 for flowing propane liquefied in the condenser 601. And. A line 30 for collecting residual gas is connected to the capacitor 601. The line 30 is provided with a compressor 8, a cooler 9, and a buffer tank 10. The line 30 is provided with a valve 31, and the end of the line 30 is connected to the olefin line 22. The U-shaped tube 603 is provided with a valve 604, and the end of the U-shaped tube 603 is open in the product tank 7. A line 605 for returning the vaporized propane gas to the mainstream line 28 is provided in the upper part of the product tank 7, and a valve 606 is provided in the line 605. A line 607 is connected to the line 602 in a branched manner, and a valve 608 is provided in the line 607. A jacket 72 is provided outside the product tank 7 so as to surround the outer periphery of the product tank 7. The end of the line 607 is connected to the jacket 72, and cooling water is supplied to the jacket 72 via the line 607.

[Propane production example with 3 catalyst tanks]
Next, a specific example of a method for producing paraffin (propane) from olefin (propylene) and hydrogen using the paraffin production apparatus X2 having the above configuration will be described.

  First, hydrogen gas in the hydrogen cylinder 1 (same as in the first embodiment) is supplied to the mainstream line 21 at a flow rate of 104.3 NL / h, for example, in a standard state quantity. The hydrogen gas in the mainstream line 21 is pressure-reduced to 0.3 MPaG by the pressure reducing valve 11, passes through the valve 13 while being monitored by the flow meter 12, and is introduced into the catalyst tank 3 through the gas inlet 3 a. .

  On the other hand, propylene gas (manufactured by Mitsui Chemicals, Inc.) as raw material olefin gas is supplied from the olefin cylinder 2 to the olefin line 22. The propylene gas contains 99.99 mol% of propylene and 0.01 mol% of propane as an impurity, and is supplied at a flow rate of 100.3 NL / h in a standard state. The propylene gas in the olefin line 22 is decompressed to 0.3 MPaG by the pressure reducing valve 14, and then 33.4 NL / h corresponding to 1/3 of the total flow rate 100.3 NL / h enters the branch line 23. , Passing through the valve 16 while being monitored by the flow meter 15, and added to the mainstream line 21. Propylene gas merged in the mainstream line 21 is introduced into the catalyst tank 3 through the gas inlet 3a.

  The catalyst tank 3 has an inner diameter of 30.7 mm, and the total filling height of the catalyst regions 301 and 302 is 800 mm. In the catalyst region 301, catalyst particles having a particle diameter of 3 mm (same as in the first embodiment) in which 0.5 wt% palladium is supported on alumina serving as a carrier are 0.003 L and alumina balls having a particle diameter of 3 mm (the first 0.293 L is mixed and 0.296 L in total is filled, and the filling height is 400 mm. Further, in the catalyst region 302, 0.030L of the same catalyst particles as in the catalyst region 301 and 0.266L of alumina balls having a particle diameter of 3mm are mixed, and a total of 0.296L is filled, and the filling height is 400mm. is there.

  Regarding the gas G1 (hydrogen gas and propylene gas) introduced into the catalyst tank 3, the mixing ratio (molar ratio) of hydrogen and propylene is 104.3 / 33.4 = 3.1 for hydrogen gas / propylene gas, Hydrogen is in excess of propylene. The introduced gas G1 to the catalyst tank 3 passes through the catalyst regions 301 and 302 and is guided to the gas outlet 3b. Here, the space velocity SV of the hydrogen gas and propylene gas passing through the catalyst regions 301 and 302 is (104.3 + 33.4) / (0.296 × 2) = 233 / h on the basis of the standard state.

  In the catalyst regions 301 and 302, a reduction reaction that is an exothermic reaction proceeds by the action of the reduction catalyst. That is, propane is produced by a reduction reaction of propylene with hydrogen. Here, the hydrogen gas / propylene gas molar ratio of the gas flowing to the catalyst tank 3 is 3.1, and the hydrogen gas / propylene gas molar ratio of the gas flowing to the catalyst tank 3 shown in FIG. Since the hydrogen excess is greater than in 1), the reduction reaction is easier to proceed than in the case of the catalyst tank 3 of FIG. Chiller water at 10 ° C. is supplied to the jacket 32 through the line 33 to cool the catalyst tank 3 from the outside, and the reaction temperature in the catalyst regions 301 and 302 becomes a predetermined temperature (about 20 ° C.) of 100 ° C. or less. Have been adjusted so that. In the catalyst regions 301 and 302, all of the propylene in the introduced gas G1 becomes propane by a reduction reaction.

  As a result of the reduction reaction in the catalyst regions 301 and 302, the gas G2 derived from the gas outlet 3b has a hydrogen gas amount of 70.9 NL / h and a propane gas amount of 33.4 NL / h, for a total of 104.3 NL / h. It becomes. The gas G2 flows toward the next catalyst tank 4 through the mainstream line 24, and is introduced into the catalyst tank 4 through the gas inlet 4a.

  On the other hand, 33.4 NL / h corresponding to 1/3 of the propylene gas (total flow rate 100.3 NL / h) in the olefin line 22 enters the branch line 25 and passes through the valve 18 while being monitored by the flow meter 17. And added to the mainstream line 24. The propylene gas merged in the main flow line 24 is introduced into the catalyst tank 4 through the gas inlet 4a.

  Similarly to the catalyst tank 3, the catalyst tank 4 has an inner diameter of 30.7 mm, and the total filling height of the catalyst regions 401 and 402 is 800 mm. In the catalyst region 401, an alumina ball having a particle size of 3 mm and a catalyst particle having a particle size of 3 mm (same as the catalyst region 301 of the catalyst tank 3) on which alumina of 0.5 wt% palladium is supported is the same. The same as the catalyst region 301 of the catalyst tank 3 is mixed with 0.293 L, and a total of 0.296 L is filled, and the filling height is 400 mm. In the catalyst region 402, 0.030L of the same catalyst particles as in the catalyst region 401 and 0.263L of alumina balls having a particle diameter of 3 mm are mixed and filled with a total of 0.296L, and the filling height is 400 mm.

  Regarding the gas G3 introduced into the catalyst tank 4, the mixing ratio (molar ratio) of hydrogen and propylene is 70.9 / 33.4 = 2.1 for hydrogen gas / propylene gas, and hydrogen is excessive with respect to propylene. It has become. The introduced gas G3 to the catalyst tank 4 passes through the catalyst regions 401 and 402 and is guided to the gas outlet 4b. Here, the space velocity SV of hydrogen gas and propylene gas passing through the catalyst regions 401 and 402 is (70.9 + 33.4) / (0.296 × 2) = 176 / h based on the standard state.

  In the catalyst regions 401 and 402, a reduction reaction that is an exothermic reaction proceeds by the action of the reduction catalyst. That is, propane is produced by a reduction reaction of propylene with hydrogen. Here, chiller water at 10 ° C. is supplied to the jacket 42 through the line 43 to cool the catalyst tank 4 from the outside so that the reaction temperature in the catalyst regions 401 and 402 becomes a predetermined temperature (about 20 ° C.). Has been adjusted. In the catalyst regions 401 and 402, all of the propylene in the introduced gas G3 becomes propane by a reduction reaction.

  As a result of the reduction reaction in the catalyst regions 401 and 402, the gas G4 derived from the gas outlet 4b has a hydrogen gas amount of 37.4 NL / h and a propane gas amount of 66.9 NL / h, for a total of 104.3 NL / h. It becomes. The gas G4 flows toward the next catalyst tank 5 through the main flow line 26, and is introduced into the catalyst tank 5 through the gas introduction port 5a.

  On the other hand, of propylene gas in the olefin line 22 (total flow rate 100.3 NL / h), 33.4 NL / h corresponding to 1/3 enters the branch line 27 and passes through the valve 20 while being monitored by the flow meter 19. And added to the mainstream line 26. The propylene gas merged in the main flow line 26 is introduced into the catalyst tank 5 through the gas introduction port 5a.

  The catalyst tank 5 has an inner diameter of 30.7 mm as in the catalyst tanks 3 and 4, while the total filling height of the catalyst regions 501, 502, and 503 is 900 mm. In the catalyst region 501, an alumina ball having a particle size of 3 mm (0.003 L) and a catalyst particle having a particle size of 3 mm (same as the catalyst region 301 of the catalyst tank 3) supported on alumina having 0.5 wt% of palladium as a carrier ( The same as the catalyst region 301 of the catalyst tank 3 is mixed with 0.293 L, and a total of 0.296 L is filled, and the filling height is 400 mm. In the catalyst region 502, 0.030 L of the same catalyst particles as in the catalyst region 501 and 0.263 L of alumina balls having a particle diameter of 3 mm are mixed to fill a total of 0.296 L, and the filling height is 400 mm. In the catalyst region 503, only 0.074 L of the same catalyst particles as in the catalyst region 501 are filled, and the filling height is 100 mm.

  Regarding the gas G5 introduced into the catalyst tank 5, the mixing ratio (molar ratio) of hydrogen and propylene is 37.4 / 33.4 = 1.1 for hydrogen gas / propylene gas, and hydrogen is excessive with respect to propylene. It has become. The introduced gas G5 to the catalyst tank 5 passes through the catalyst regions 501, 502, and 503 and is guided to the gas outlet 5b. Here, the space velocity SV of the hydrogen gas and propylene gas passing through the catalyst regions 501, 502, and 503 is (37.4 + 33.4) / (0.296 × 2 + 0.074) = 106 / h based on the standard state standard. Become.

  In the catalyst regions 501, 502, and 503, a reduction reaction that is an exothermic reaction proceeds by the action of the reduction catalyst. That is, propane is produced by a reduction reaction of propylene with hydrogen. Here, 10 ° C. chiller water is supplied to the jacket 52 through the line 53 to cool the catalyst tank 5 from the outside, and the reaction temperature in the catalyst regions 501, 502, and 503 is a predetermined temperature (about 20 ° C.). It has been adjusted to be. In the catalyst regions 501, 502, and 503, all of the propylene in the introduced gas G5 becomes propane by the reduction reaction.

  As a result of the reduction reaction in the catalyst regions 501, 502, and 503, the gas G6 derived from the gas outlet 5b has a hydrogen gas amount of 4.0 NL / h and a propane gas amount of 100.3 NL / h, for a total of 104.3 NL. / H. The gas G6 is introduced into the condenser 601 of the partial reduction device Y2 through the mainstream line 28.

  The residual propylene concentration in the gas G6 (production gas) flowing through the mainstream line 28 was analyzed by gas chromatography and found to be less than 1 ppm and below the detection limit. In the reduction reaction in the entire three of the catalyst tanks 3, 4, and 5, the total mixing molar ratio of hydrogen / propylene is 104.3 / 100.3 = 1.04, and hydrogen is 3.8 in the production gas. Mole% remains.

  Then, the production gas in the mainstream line 28 is introduced into the capacitor 601 of the partial reduction device Y2. The condenser 601 is supplied with chiller water of -20 to -10 ° C through the line 602 from the outside, and propane is cooled and condensed under about 0.3 MPaG. The residual hydrogen that has not been condensed is compressed by the compressor 8 through the line 30, cooled by the cooler 9, and collected in the buffer tank 10. The recovered hydrogen passes from the buffer tank 10 through the valve 31 to the olefin line 22 and is recycled to the raw material system. On the other hand, the propane from which hydrogen has been removed and liquefied is stored as high-purity propane in the product tank 7 through the U-shaped tube 603.

  In this production example, a plurality of catalyst tanks 3, 4, and 5 are installed separately in series, and olefin (propylene) is dividedly added to each of the catalyst tanks 3, 4, and 5 using hydrogen as a mainstream. The reduction reaction of olefin (propylene) with hydrogen becomes easier to proceed by adding more hydrogen than the theoretical equivalent. Accordingly, the three catalyst tanks 3, 4 and 5 are divided in series, and the amount of hydrogen / olefin in each catalyst tank 3, 4, and 5 is added by dividing and adding olefin (propylene) mainly using hydrogen. The amount (molar ratio) can be increased, and the reduction reaction can be promoted. Furthermore, since the olefin (propylene) is added in portions, an increase in the reaction temperature per each of the catalyst tanks 3, 4 and 5 can be suppressed.

  The ratio of the amount of hydrogen to the amount of olefin in the gases G1, G3, G5 introduced into the catalyst tanks 3, 4, 5 is such that the hydrogen amount / olefin amount (molar ratio) is 1.1 or more. , 5 has an equal amount of olefin in the introduced gases G1, G3, G5. The mainstream hydrogen passes through the catalyst tanks 3, 4, 5 sequentially and is consumed and reduced in the reduction reaction with the olefin, so that the hydrogen / olefin is 1.1 or more in the most downstream catalyst tank 5. The amount is set. As a result, in the gas G3 introduced into the catalyst tank 4 (one upstream side of the catalyst tank 5), the hydrogen amount is an amount obtained by adding the amount consumed by the reduction reaction in the catalyst tank 4. The amount / olefin amount is 2.1 or more. Similarly, in the gas G1 introduced to the catalyst tank 3 (one upstream side of the catalyst tank 4), the hydrogen amount is an amount obtained by adding the amount consumed in the reduction reaction in the catalyst tank 4, The amount of hydrogen / the amount of olefin is 3.1 or more.

  When three catalyst tanks are connected in series, the total hydrogen / propylene mixing molar ratio is 1.04 as described above, and the amount of propane gas in the production gas (104.3 NL / h) is 100.3 NL. / H, the amount of hydrogen gas is 4.0 NL / h, and the residual hydrogen concentration is 3.8 mol%. Compared to the case of FIG. 1 in which two catalyst tanks are connected in series (the amount of propane gas in the production gas is 99.4 NL / h, the amount of hydrogen gas is 4.9 NL / h, and the residual hydrogen concentration is 4.7 mol%). Even if the same amount of hydrogen (104.3 NL / h) was used, the amount of propane produced increased by 1% and the residual hydrogen concentration decreased by 0.9 mol%, so an additional catalyst tank was provided. There is an effect. In addition, since the amount of heat generated by the reaction heat in each catalyst tank is reduced by 30% or more, it becomes easy to perform external cooling and temperature control.

  The table in FIG. 3 shows a propane production example in which the catalyst tanks are divided in series and the number of installed tanks is sequentially increased to 2 to 5 tanks as compared with the case of only one tank.

In each catalyst tank, a catalyst particle having a particle diameter of 3 mm in which 0.5 wt% palladium was supported on alumina (Al ₂ O ₃ ) and alumina balls having a particle diameter of 3 mm were mixed and packed in a volume of 1:99 on the upstream side. The catalyst area and the catalyst area mixed and filled at 10:90 were laminated at a filling height of 400 mm, respectively, and only the final catalyst tank and only the catalyst particles were filled at a filling height of 100 mm. Each catalyst tank was operated by controlling the reaction temperature at 20 ° C. while cooling with chiller water.

  When the amount of mainstream hydrogen as a raw material gas is 104.3 NL / h and the number of catalyst tanks is two, when the hydrogen gas / propylene gas molar ratio of the introduction gas to each catalyst tank is 1.1 or more, the raw material gas The propylene gas amount of was 99.4 NL / h, and the total mixing molar ratio of hydrogen / propylene was 1.05. As a result, when the unreacted residual propylene concentration in the production gas and the methane concentration and ethane concentration as impurities are measured by gas chromatography (FID), each becomes less than the detection limit of less than 1 ppm, and propylene is substantially completely converted to propane. Reduced. However, the amount of excess hydrogen remaining was 4.9 NL / h, and 4.7 mol% remained in the production gas.

  Next, when the number of catalyst tanks installed was increased to 3 tanks, 4 tanks, and 5 tanks while the hydrogen gas / propylene gas molar ratio of the introduced gas to each catalyst tank was 1.1 or more, the total amount of hydrogen / propylene The mixing molar ratio decreased, the amount of residual hydrogen decreased, the amount of produced propane gas increased, and the calorific value of each catalyst tank decreased. However, when the molar ratio of hydrogen gas / propylene gas in the gas introduced into the catalyst tank was lowered to 1.0, the amount of propane gas as the production gas increased, but the residual hydrogen amount became zero, and the reduction reaction was completely completed. As measured by gas chromatography (FID), a residual propylene concentration of 5 ppm, a methane concentration of 2 ppm as an impurity, and an ethane concentration of 1 ppm were detected in the production gas. From this result, in order to ensure 100% reduction reaction in each catalyst tank, the molar ratio of hydrogen gas / propylene gas in the gas introduced into each catalyst tank needs to be 1.1 or more. .

  When there is only one catalyst tank, the mainstream hydrogen amount as the raw material gas is made to flow 104.3 NL / h, and the propylene gas amount as the raw material gas is adjusted so that the hydrogen gas / propylene gas molar ratio is 1.1 or more. 94.8 NL / h flowed and introduced into the catalyst tank. Although the unreacted residual propylene concentration in the production gas was below the detection limit, the methane concentration as an impurity was detected at 4 ppm, and the ethane concentration was detected at 3 ppm. Propylene was completely reduced to propane, but the amount of excess hydrogen remaining was the largest at 9.5 NL / h. Here, as a cause of detecting methane and ethane, first, when there are two or more catalyst tanks, the reaction heat is dispersed for each catalyst tank and the rise in reaction temperature is suppressed. It is considered that the temperature suppression effect due to the dispersion of reaction heat cannot be obtained. Second, when the catalyst tank has only one tank and the hydrogen / propylene molar ratio of the raw material gas is 1.1, it is relatively smaller than the hydrogen / propylene ratio in the catalyst tank when there are two or more catalyst tanks. (For example, when the number of catalyst tanks is two, the hydrogen / propylene ratio in the first tank is 2.1, and when the number of catalyst tanks is three, the hydrogen / propylene ratio in the first tank is 3.1, The hydrogen / propylene ratio is 2.1). Thus, when the ratio of the amount of hydrogen introduced into the catalyst tank is small, it is considered that propylene is easily decomposed during the reaction process, and methane and ethane are generated.

[Example of ethane production with two catalyst tanks]
Next, when the olefin is ethylene, ethane can be produced from ethylene and hydrogen using, for example, the paraffin production apparatus X1 shown in FIG. Olefin line from olefin cylinder 2 at a flow rate of 99.4 NL / h in a standard state of crude ethylene gas (produced by Nippon Fine Gas Co., Ltd.) containing 99.4 mol% ethylene and 0.6 mol% ethane as impurities. 22, 49.7 NL / h was divided into two equal parts and flowed into the catalyst tanks 3 and 4. The first catalyst tank 3 has an inner diameter of 30.7 mm, and catalyst particles with a particle diameter of 3 mm in which 0.5 wt% rhodium is supported on alumina (Al ₂ O ₃ ) in the upstream catalyst region 301. 0.003 L (made by Aldrich) and 0.293 L of alumina balls having a particle diameter of 3 mm were mixed and filled, and the filling height was 400 mm. The downstream catalyst region 302 was mixed with 0.03 L of the same catalyst particles as the catalyst region 301 and 0.266 L of alumina balls, and a total of 0.296 L was filled, and the filling height was 400 mm. The catalyst tank 4 of the second tank has an inner diameter of 30.7 mm, and catalyst particles 0 having a particle diameter of 3 mm in which 0.5 wt% rhodium is supported on alumina (Al ₂ O ₃ ) in the catalyst region 401 on the most upstream side. 0.003 L and 3 mm alumina balls 0.293 L are mixed and filled, and the middle catalyst area 402 is filled with 0.030 L of the same catalyst particles as the catalyst area 401 and 0.266 L of the same alumina balls as the catalyst area 401. It was done. The catalyst region 403 on the most downstream side was filled with 0.074 L of only the same catalyst particles as the catalyst region 401. The filling height of the catalyst areas 401, 402, and 403 was 400 mm for the catalyst area 401, 400 mm for the catalyst area 402, and 100 mm for the catalyst area 403, and the filling height was 900 mm in total. Ethylene was added to each of the catalyst tanks 3 and 4 while flowing 104.3 NL / h of hydrogen as a main stream in series in the two tanks 3 and 4. In the catalyst tanks 3 and 4 (catalyst regions 301, 302, 401, 402, and 403), the reduction reaction of ethylene with hydrogen proceeds, and inside the catalyst tanks 3 and 4 while chiller water of 10 ° C. is allowed to flow from outside to the jackets 32 and 42. Was controlled to be about 20 ° C. As a result, when the residual ethylene concentration in the production gas derived from the gas outlet 4b of the second catalyst tank 4 was analyzed by gas chromatography (FID), it was less than 1 ppm below the detection limit, and substantially all ethane It was reduced to.

  Although specific embodiments of the present invention have been described above, the scope of the present invention is not limited to the above-described embodiments. The specific configuration of the paraffin manufacturing apparatus according to the present invention and the paraffin manufacturing method according to the present invention can be variously modified without departing from the spirit of the invention.

As an aspect of diluting the catalytically active substance with the dilution medium, in the above embodiment, the catalyst particles supporting the catalytically active substance (palladium or rhodium) on the support are diluted with an inorganic filler (alumina ball), and the inorganic filler Although the case where the mixing ratio is varied stepwise has been described as an example, the present invention is not limited to this. As a method for diluting the catalytically active substance, for example, without using an inorganic filler, the ratio of the catalytically active substance supported on the carrier is gradually increased to 0.1 wt%, 0.2 wt%, 0.5 wt%, etc. In this method, the same effect as the method of diluting with an inorganic filler can be obtained. Further, as the catalytically active substance, a metal containing at least one selected from platinum, ruthenium, and nickel may be used instead of palladium or rhodium. The catalytically active substance is not limited to the mode supported by the support (Al ₂ O ₃ ), and may be used alone. The inorganic filler is not limited to a ceramic material such as an alumina ball, and a metal ball made of iron or stainless steel may be used.

  The olefin as the raw material gas is not limited to the above-mentioned propylene or ethylene, and for example, butene in a gas phase state at normal temperature (around 20 ° C.) may be used.

X1, X2 Paraffin production device Y1 PSA gas separation device Y2 Reduction device 1 Hydrogen cylinder 2 Propylene cylinders 3, 4, 5 Catalyst tank 6A, 6B Adsorption tank 7 Product tank 8 Compressor 9 Cooler 10 Buffer tank 11, 14 Pressure reducing valve 12 15, 17, 19 Flow meter 13, 16, 18, 20, 31 Valve 21, 24, 26, 28 Main line 22 Olefin line 23, 25, 27 Branch line 29, 30, Line 32, 42, 52, 72 Jacket 33, 43, 53 Line 60 Adsorbent 61a, 61b, 61c, 61d, 61e, 61f Line 62a, 62b, 62c, 62d, 62e, 62f Switching valve 301, 302, 401, 402, 403, 501, 502, 503 Catalyst Region 601 Capacitors 602, 605, 607 Line 603 U-tube 604 606, 608 valve

Claims (19)

A method for producing paraffin from a olefin and hydrogen in a gas phase by a reduction reaction that proceeds in the presence of a reduction catalyst,
A plurality of catalyst tanks each filled with the reduction catalyst are provided in series along a mainstream line through which hydrogen flows,
The olefin is divided into the mainstream line so that the amount of hydrogen in the gas introduced into each catalyst tank (molar amount of hydrogen, hereinafter the same) is greater than the amount of olefin (molar amount of olefin, hereinafter the same). A method for producing paraffin, which comprises adding the paraffin.   2. The method for producing paraffin according to claim 1, wherein a ratio of hydrogen amount / olefin amount (molar ratio) in the gas introduced into each catalyst tank is 1.1 or more.   The method for producing paraffin according to claim 1 or 2, wherein the amount of olefin in the gas introduced into each of the plurality of catalyst tanks is equal. The reduction catalyst filled in the catalyst tank includes a product obtained by diluting a catalytically active substance having catalytic activity with a diluent medium having no catalytic activity,
The method for producing paraffin according to any one of claims 1 to 3, wherein the mixing ratio of the dilution medium is lowered stepwise from the upstream side to the downstream side of the catalyst tank.   The method for producing paraffin according to claim 4, wherein the dilution medium includes a carrier supporting the catalytically active substance.   The method for producing paraffin according to claim 4 or 5, wherein the catalytically active substance is made of a metal containing at least one selected from palladium, rhodium, platinum, ruthenium, and nickel.   The method for producing paraffin according to claim 4, wherein the dilution medium includes an inorganic filler.   The method for producing paraffin according to any one of claims 1 to 7, wherein the olefin has 2 to 4 carbon atoms and the paraffin has 2 to 4 carbon atoms. An apparatus for producing paraffin by a reduction reaction that proceeds in the presence of a reduction catalyst from an olefin and hydrogen in a gas phase,
A mainstream line for flowing hydrogen,
A plurality of catalyst tanks provided in series along the mainstream line, each having a gas inlet and a gas outlet, and filled with the reduction catalyst;
Hydrogen supply means for supplying hydrogen to the mainstream line;
An olefin addition unit for adding the olefin through the branch line, the branch line connected to the mainstream line upstream of the gas introduction part of the catalyst tank. Paraffin manufacturing equipment.   The apparatus for producing paraffin according to claim 9, wherein the number of installed catalyst tanks is in the range of 2 to 5.   The apparatus for producing paraffin according to claim 9 or 10, comprising temperature adjusting means for adjusting the internal temperature of the catalyst tank. The reduction catalyst filled in the catalyst tank includes a plurality of catalyst regions in which a catalytically active substance having catalytic activity is diluted with a diluent medium that does not have catalytic activity, and the mixing ratio of the diluent medium is different from each other. And
The paraffin production apparatus according to any one of claims 9 to 11, wherein a mixing ratio of the dilution medium in the plurality of catalyst regions is gradually reduced from an upstream side to a downstream side in the catalyst tank. .   The apparatus for producing paraffin according to claim 12, wherein the number of catalyst regions arranged is in the range of 2 to 5.   The apparatus for producing paraffin according to claim 12 or 13, wherein the dilution medium includes a carrier supporting the catalytically active substance.   15. The apparatus for producing paraffin according to claim 12, wherein the catalytically active substance is made of a metal containing at least one selected from palladium, rhodium, platinum, ruthenium, and nickel.   The apparatus for producing paraffin according to any one of claims 12 to 15, wherein the dilution medium includes an inorganic filler.   The apparatus for producing paraffin according to any one of claims 9 to 16, wherein a hydrogen removing means is provided downstream of the plurality of catalyst tanks in the mainstream line in order to remove hydrogen.   18. The apparatus for producing paraffin according to claim 17, wherein the hydrogen removal means includes a pressure fluctuation adsorption gas separation device.   18. The apparatus for producing paraffin according to claim 17, wherein the hydrogen removing means includes a partial reduction device.

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