JPH0511045B2 - - Google Patents

Description

[Detailed description of the invention]

"Industrial Application Field" This invention relates to a method for producing hydrogen sulfide by reacting sulfur and hydrogen. "Prior art and its problems" The method of producing hydrogen sulfide by reacting sulfur and hydrogen in the gas phase is well known, but when sulfur and hydrogen are reacted, the temperature rises significantly due to the heat of reaction. Therefore, temperature control of the reactor is required. Conventionally, as a countermeasure against this problem, a method is generally known in which a large excess of hydrogen is used and a small amount of sulfur is used to limit the amount of reaction between the two, thereby suppressing the temperature rise. However, with this method, not only is the product hydrogen sulfide concentration around 10% and the hydrogen utilization rate is low, but the size of the equipment per unit of hydrogen sulfide production is large, and a large amount of hydrogen must be circulated. There were problems in that excessive equipment for absorption and regeneration processes was required, the hydrogen sulfide production efficiency was low, and the production equipment became large and expensive. Therefore, as an improvement to the above method, two or more gas phase reaction chambers are installed in series, and hydrogen heated to a temperature sufficient to vaporize sulfur is passed in series at the entrance of each reaction chamber. A method has been proposed in which sulfur is dividedly supplied to a sulfur-introducing vaporization chamber for reaction. (Japanese Patent Publication No. 46-5572) However, even with this method, in order to suppress the temperature rise within 100°C in one stage, only about 1 mol% of S ₈ (sulfur vapor) can be reacted. In order to achieve a high concentration, a large number of stages are required, which is therefore uneconomical. The present invention was made in view of the above circumstances, and efficiently controls the reaction temperature of sulfur and hydrogen.
The purpose of the present invention is to provide a production method that can simultaneously obtain hydrogen sulfide at a high concentration. "Means for Solving the Problems" In order to achieve the above object, the present invention provides a method for producing hydrogen sulfide by reacting sulfur and hydrogen, in which a catalyst accommodates sulfur and hydrogen, at least partially in a liquid phase. The sulfur is supplied into a reactor, and the sulfur and hydrogen are brought into contact with each other to carry out a reaction. "Effect" Hydrogen sulfide is produced by supplying sulfur and hydrogen, at least part of which are in the liquid phase, into a reactor and bringing them into contact.The heat of reaction generated at this time causes part of the sulfur to vaporize. By absorbing the reaction heat, the temperature rise in the reactor is suppressed. "Example" An example will be described with reference to the drawings. 1st
The figure is for explaining one example of the method for producing hydrogen sulfide of the present invention, and the reference numeral 1 in the figure is a reactor, 2
is liquid sulfur. A hydrogenation catalyst is suspended in this liquid sulfur 2 to form a reaction phase. Heated hydrogen is supplied to the liquid sulfur 2 in the reactor 1 through a line 3, and liquid sulfur is supplied through lines 4 and 5. In this liquid sulfur 2, in the presence of a catalyst, liquid sulfur and hydrogen are brought into gas-liquid contact, and a reaction is carried out to produce hydrogen sulfide. As this hydrogen, steam reformed hydrogen such as LPG and naphtha, electrolyzed hydrogen, hydrogen recovered from another plant, etc. are used. Further, sulfur is supplied from line 6 located on the right side in this figure, and is supplied from the above-mentioned lines 4 and 5 together with circulating liquid sulfur, which will be described later. The heater 7 inserted into the reactor 1 is used to heat the reactor 1 at the start of production. Temperature of liquid sulfur 2 in reactor 1 (reaction temperature)
is maintained at a constant temperature in balance by the heat of reaction generated by the reaction with hydrogen and the vaporization of liquid sulfur 2. This reaction temperature is preferably in the range of 250°C to 450°C. If the reaction temperature is lower than this, not only the reaction rate will decrease, but also the viscosity of the liquid sulfur 2 will increase. On the other hand, if the reaction temperature is higher than this, the sulfur vapor pressure will increase, resulting in disadvantages such as an increase in the amount of sulfur vapor entrained in the generated gas, deterioration of the catalyst, and corrosion of the equipment of the reactor 1. Further, it is desirable that the reaction pressure be adjusted to the pressure required for the hydrogen sulfide product. As the catalyst, oxides or sulfides of cobalt-molybdenum or nickel-molybdenum, nickel sulfide, and the like, which are known as hydrogenation catalysts, are preferably used. The gas flowing out from the reactor 1 contains hydrogen sulfide, sulfur vapor, unreacted hydrogen, methane and impure gases supplied together with the hydrogen, and is flowed out from the reactor 1 through the line 8. However, before that, all or part of the liquid sulfur supplied into the reactor 1 may be supplied to the upper part of the reactor 1 from the line 5 to lower the temperature of the gas and reduce the amount of sulfur vapor entrained. It is possible. Furthermore, if the catalyst suspended in the liquid sulfur 2 is entrained in the droplets and adheres to the walls of the reactor or pipes, and a reaction occurs there, there may be an inconvenience that the temperature in that area becomes high. By supplying liquid sulfur from the line 5, the catalyst adhering to the vessel wall etc. is washed off and returned to the liquid sulfur 2, thereby preventing the above-mentioned inconvenience. In addition, in some cases, in order to further react the sulfur vapor entrained in the generated gas, all or part of the gas flowing out from the reactor 1 is supplied to the hydrogenation reactor 9 to combine sulfur vapor and hydrogen. may be subjected to a gas phase catalytic reaction, and the sulfur vapor mixed in the generated gas may be converted into hydrogen sulfide. The product gas produced in reactor 1 is passed through line 8
is sent to the cooler 10 to be cooled and to condense the entrained sulfur vapor. This cooling method is performed by water cooling, heat exchange with raw material hydrogen, air, or other gas, or the like. The cooling temperature is preferably about 150 to 130°C in order to condense as much sulfur vapor in the generated gas as possible and prevent it from solidifying. In addition, during this cooling operation, by supplying a part of the raw material liquid sulfur to the upstream side of the cooler 10 through the line 11 or to the separator 12 connected to the cooler 10, the produced gas can be cooled. It is also possible to reduce the viscosity of liquid sulfur by producing polysulfide (H ₂ Sx) by contacting it with the contained hydrogen sulfide. The cooled product gas is then separated from liquid sulfur by a separator 12, whereby a product gas containing mainly hydrogen sulfide is taken out from a line 13. At this time, if the cooling temperature in the cooler 10 is higher than the temperature of the raw material liquid sulfur, the raw material liquid sulfur is supplied from the line 6 to the gas phase part of the separator 12 and remains in the generated gas. Separation efficiency can be increased by purifying sulfur vapor. The produced gas taken out from the line 13 mainly consists of hydrogen sulfide, saturated sulfur vapor, impurity gases (such as methane) in the raw hydrogen, and the like. The hydrogen sulfide concentration in this generated gas depends on the reaction conditions.
Concentrations can be made as high as 90% or more. In addition, when the amount of mixed sulfur vapor is kept below the saturation amount, the entire amount of generated gas flowing out from the reactor 1 is transferred to the hydrogenation reactor 9.
to convert substantially all of the sulfur vapor into hydrogen sulfide,
A method is used in which raw material liquid sulfur is supplied into the reactor 1 through line 14 without supplying liquid sulfur through line 6 or line 11. In the separator 12, the condensed and separated liquid sulfur is circulated and supplied to the reactor 1 through lines 4 and 5 together with liquid sulfur supplied from line 6. In the method for producing hydrogen sulfide according to this example, even if reaction heat is generated, the increase in reaction temperature is suppressed by heating the supplied liquid sulfur and hydrogen and using it to vaporize the liquid sulfur, and the vaporized sulfur Since hydrogen sulfide can be easily separated by cooling the produced gas, high concentration hydrogen sulfide can be produced in the single-stage reactor 1. Further, in order to control the reaction temperature, it is not necessary to use a large excess of hydrogen as in the conventional method, and the amount of hydrogen used to produce hydrogen sulfide can be reduced. Furthermore, the reactor can be made smaller, the auxiliary equipment can be made smaller, and the manufacturing equipment can be made smaller. 2 to 5 show other examples of the method of the present invention. In FIG. 2, hydrogen and liquid sulfur are supplied from below the honeycomb catalyst 20 through lines 3 and 4 into a reactor 21 in which a honeycomb catalyst 20 is immersed in liquid sulfur 2, and a reaction is carried out in the liquid sulfur 2. This is an example. In this example, in addition to obtaining the same effects as the method shown in FIG. 1, the liquid sulfur 2 can be circulated by bubbling the supplied hydrogen. Furthermore, when the reaction is stopped and the liquid sulfur 2 in the reactor 21 is extracted, unlike the suspended catalyst in the reactor 1 shown in FIG. 1, it is possible to prevent catalyst powder from being mixed into the liquid sulfur. In FIG. 3, a granular catalyst packed bed 22 is placed in a reactor 23 in which the granular catalyst packed bed 22 is immersed in liquid sulfur 2.
This shows an example in which hydrogen and liquid sulfur are supplied from below through lines 3 and 4, respectively, and the reaction is carried out within the liquid sulfur 2. In this example, substantially the same effect as the example shown in FIG. 2 can be obtained. However, since it is in liquid sulfur with a specific gravity of 1.8, care must be taken to prevent the catalyst particles from dancing as the liquid sulfur rises. FIG. 4 shows that liquid sulfur is supplied from above the fixed catalyst bed 24 and hydrogen is supplied from below the fixed catalyst bed 24 into a reactor 25 equipped with a fixed catalyst bed 24 consisting of the honeycomb catalyst 20 or the granular catalyst packed bed 22. An example is shown in which the reaction occurs while sulfur flows down over the surface of a fixed catalyst bed 24. The liquid sulfur 2 accumulated in the lower part of the reactor 25 is circulated to the upper part of the fixed catalyst bed 24 through a line 26. In this example, the amount of liquid sulfur 2 stored in the reactor 25 can be reduced compared to the examples shown in FIGS. 1 to 3 described above, and the temperature of the generated gas flowing out from the reactor 25 can be reduced. Since it is possible to reduce the amount of sulfur vapor entrained in the generated gas, it is possible to reduce the amount of sulfur vapor entrained in the generated gas. However, it is necessary to adjust the temperature inside the reactor 25 and the amount of liquid sulfur or hydrogen supplied so that the flow of liquid sulfur is not delayed and the liquid sulfur does not overflow. FIG. 5 shows a reactor 27 with a fixed catalyst bed 24.
Liquid sulfur and hydrogen are each supplied from above the fixed catalyst bed 24, and the reaction is carried out while the liquid sulfur flows down on the surface of the fixed catalyst bed 24. It was designed so that it could be taken out. According to this example, in addition to obtaining substantially the same effect as shown in FIG. 4, it is possible to prevent the flow of liquid sulfur from being obstructed and from overflowing. (Production Example) Using the apparatus shown in FIG. 6, hydrogen sulfide was produced based on the method of the present invention. The reactor 23 had a structure in which a granular catalyst packed bed 22 filled with a Co-Mo hydrogen sulfide catalyst (particle size 3 to 5 mm) supported on alumina was immersed in the liquid sulfur 2. Hydrogen 5.0Nm ³ /Hr is introduced into this reactor 23 through line 3.
At the same time, 6.9 Kg/Hr of liquid sulfur is supplied from line 6, and 12.6 Kg/Hr of circulating liquid sulfur separated in separator 12 is supplied to reactor 23 through line 4 to react. Vessel 23
The reaction was carried out in liquid sulfur 2. The reaction conditions are a reaction temperature of 380℃ and a reaction pressure of 3Kg/cm ² G.
It was set to The produced gas flowing out from the reactor 23 was cooled to 140° C. in the cooler 10, and the sulfur vapor contained in the produced gas was condensed and separated in the separator 12, while the produced gas was obtained through the line 13. Table 1 shows the composition of the resulting gas. (This is referred to as an example in Table 1.) For comparison with the method of the present invention, hydrogen sulfide was produced using the production apparatus shown in FIG. . In this comparative example, a reactor 30 containing a granular catalyst packed bed 22 similar to that used in the above example was used.
50Nm ³ /Hr of hydrogen from line 3 and 5.8Kg/Hr of liquid sulfur supplied through line 31 are mixed and heated to a temperature of 300°C to form a gas, and the mixed gas is fed to reactor 30 through line 32. supply,
The reaction was carried out. Due to the reaction heat, the outlet of the reactor 30
The temperature had risen to 380℃. Also, the reaction pressure is 3Kg/
It was cm ² G. The generated gas flowing out from the reactor 30 is then sent to the cooler 10 through the line 33 40
It was cooled to ℃ and passed through a separator 12 to obtain a product gas. At this time, all the sulfur in the raw material had become hydrogen sulfide, so no liquid sulfur was found in the separator 12. The composition of the resulting gas was analyzed in the same manner as in the above example, and the results are shown in Table 1. (Table 1
This is referred to as a comparative example. )

[Table] As is clear from Table 1, high concentration hydrogen sulfide can be easily obtained according to the method of the present invention. Also, compared to the conventional method, it is clear that the flow rate of hydrogen as a raw material is 1/10 to produce the same amount of hydrogen sulfide. "Effects of the Invention" As explained above, the method for producing hydrogen sulfide according to the present invention involves supplying hydrogen to sulfur that is at least partially in a liquid phase into a reactor containing a catalyst, and then combining the sulfur and hydrogen. By bringing it into contact and causing a reaction,
The reaction heat generated by the reaction of sulfur and hydrogen is absorbed by the vaporization of liquid sulfur in the reactor, which suppresses the rise in reaction temperature, and the vaporized sulfur cools the produced gas. Therefore, since it can be easily separated, highly concentrated hydrogen sulfide can be produced extremely efficiently using a single-stage reactor. Furthermore, in order to control the reaction temperature, there is no need to use a large excess of hydrogen as in the conventional method, and the flow rate of hydrogen used to produce hydrogen sulfide can be reduced. Furthermore, since the reactor can be made smaller and ancillary equipment such as raw material circulation equipment can be made smaller, the manufacturing apparatus can be made smaller.

[Brief explanation of the drawing]

Figure 1 shows a method for producing hydrogen sulfide according to the present invention.
2 to 5 are diagrams for explaining other examples of the manufacturing method of the present invention, showing the main parts of the manufacturing device. FIG. FIG. 6 is a schematic diagram of a manufacturing apparatus used in a manufacturing example according to the method of the present invention, and FIG. 7 is a schematic diagram of a manufacturing apparatus according to a conventional method used as a comparative example. 1, 21, 23, 25, 27...reactor, 2
0,22,24...Catalyst.

Claims (1)

[Claims] 1. In a method for producing hydrogen sulfide by reacting sulfur and hydrogen, sulfur and hydrogen, at least partially in a liquid phase, are supplied into a reactor containing a catalyst, and the sulfur and hydrogen are brought into contact to cause a reaction. A method for producing hydrogen sulfide, characterized in that: