JP7185993B2 - Sulfur compound adsorbent and method for producing the same - Google Patents

Description

The present invention relates to an adsorbent for removing sulfur compounds contained in hydrocarbons.

Hydrocarbons obtained from crude oil or the like are processed into various chemical products such as fuels and polymeric materials through various processes such as distillation and chemical reactions. Such hydrocarbons sometimes contain sulfur compounds derived from raw materials, and these sulfur compounds are known to be one of the causes of corrosion of pipes and deterioration of catalysts. For example, it is known that propylene, for which demand has increased in recent years, contains carbonyl sulfide, which has a boiling point close to it, as an impurity. When such propylene is polymerized, carbonyl sulfide poisons the propylene polymerization catalyst. (Patent Document 1).

As a method for removing such sulfur compounds from hydrocarbons, a method using an adsorbent is known. For example, Patent Document 2 discloses a method of adsorbing and removing carbonyl sulfide in a fluid using an adsorbent in which a copper component is supported on a carrier. As a carrier for supporting this copper oxide, silica, alumina, silica-alumina, activated carbon, diatomaceous earth, activated clay, magnesia, etc. are used, and it is disclosed that alumina is particularly preferable.

As an adsorbent in which a copper component is supported on alumina, an adsorbent such as that disclosed in Patent Document 3 is also known in addition to Patent Document 2. Also known is an adsorbent in which a copper component and an aluminum component are supported on activated carbon, as disclosed in Patent Document 4.

Adsorbents for removing sulfur compounds contained in such hydrocarbons are not powdered, but have a thickness of about 0.5 to 5 mm, in order to avoid an increase in pressure loss when the hydrocarbons are passed through the adsorbent. is used. However, it is known that such adsorbents have low adsorption performance for sulfur compounds because hydrocarbons permeate the outer surface of the adsorbent, but it is difficult for hydrocarbons to permeate the interior of the adsorbent. there is

As one of the methods for solving such a problem, Patent Document 4 discloses that the shape of the molded body is spherical instead of cylindrical, and the average distance from the outer surface to the center of the adsorbent is shortened. It is disclosed to facilitate the diffusion of compounds into the pores within the adsorbent. However, the adsorbent of Patent Document 4 does not necessarily have sufficient pore diffusibility of sulfur compounds.

JP 2012-206944 A JP-A-3-213115 JP-A-59-160584 Japanese Patent Application Laid-Open No. 2000-42407 (Patent No. 3324746)

The present invention solves the problem of insufficient diffusion of conventional adsorbents into the adsorbent for removing sulfur compounds contained in hydrocarbons. To provide an adsorbent in which hydrocarbons containing sulfur compounds easily diffuse.

The adsorbent of the present invention is an adsorbent for removing sulfur compounds contained in hydrocarbons, and contains copper oxide, an aluminum compound, and activated carbon, and the activated carbon has a diameter of 0.1 μm or more to 10 μm or less. It has pores in the range, the carbon content including the activated carbon is 3% by weight or more and 15% by weight or less, and the pore distribution measured by mercury porosimetry has a diameter of 0.1 μm or more and 10 μm or less. The pore volume is 0.1 mL/g or more and 0.25 mL/g or less, the total pore volume is 0.3 mL/g or more and 0.45 mL/g or less, and the pore volume relative to the total pore volume is The sulfur compound adsorbent is characterized by having a pore volume ratio in the range of 32 to 60%.

In the present invention, in an adsorbent containing copper oxide and an aluminum compound, by increasing the volume of pores having a diameter of 0.1 μm or more to 10 μm or less, hydrocarbons containing sulfur compounds are easily diffused from the outer surface of the adsorbent to the inside. did. In order to increase the pore volume of such pores with a diameter of 0.1 μm or more and 10 μm or less, activated carbon containing a large number of pores with a diameter of 0.1 μm or more and 10 μm or less is added to the adsorbent. Facilitated the diffusion of hydrocarbons containing sulfur compounds into the interior.

The adsorbent of the present invention has a pore volume of 0.1 mL/g or more, preferably 0.1 mL/ Since it is from 0.25 mL/g to 0.25 mL/g, hydrocarbons containing sulfur compounds can easily diffuse into the interior of the adsorbent. FIG. 1 shows the adsorbent of the present invention in which sulfur compounds are adsorbed. As shown in FIG. 1, the adsorbent of the present invention has sulfur adsorbed to the center of the adsorbent. As a result, the adsorption amount of sulfur is high. On the other hand, FIG. 2 shows a state in which a sulfur compound is adsorbed by an adsorbent whose pore size is not adjusted. As shown in FIG. 2, this adsorbent does not adsorb much sulfur in the center.

2 is a micrograph showing the state of sulfur adsorption and a schematic diagram of the state of adsorption of the adsorbent of Example 1. FIG. FIG. 2 is a micrograph showing the state of sulfur adsorption and a schematic diagram of the state of adsorption of the adsorbent of Comparative Example 1. FIG. 1 is a graph showing pore distributions of carbon-containing compounds of Examples 1 to 4 and Comparative Examples 2 and 3 (activated carbon for Examples 1 to 4, graphite for Comparative Example 2, and activated carbon for Comparative Example 3) . Graphs showing pore distributions of adsorbents of Examples 1-4 and Comparative Examples 1-3.

BEST MODE FOR CARRYING OUT THE INVENTION The adsorbent of the present invention will be specifically described below based on embodiments.
[Adsorbent of the present invention]
The adsorbent of the present invention contains copper oxide, an aluminum compound, and activated carbon, the activated carbon has pores with a diameter of 0.1 μm or more and 10 μm or less, and the carbon content containing the activated carbon is 3% by weight. The volume of pores with a diameter of 0.1 μm or more and 10 μm or less is 0.1 mL/g or more and 0.25 mL/g or less in the pore distribution measured by mercury porosimetry. Sulfur, wherein the total pore volume is 0.3 mL / g or more to 0.45 mL / g or less, and the ratio of the pore volume to the total pore volume is in the range of 32 to 60%. It is a compound adsorbent.

The adsorbent of the present invention contains activated carbon having a large number of pores with diameters in the range of 0.1 μm or more to 10 μm or less, and the carbon content of the entire adsorbent containing this activated carbon is 3% by weight or more to 15% by weight or less. , in the pore distribution measured by mercury porosimetry, the pore volume of the pores is in the range of 0.1 mL / g or more to 0.25 mL / g or less, and the total pore volume is 0.3 mL / g 0.45 mL / g or less, and the ratio of the pore volume to the total pore volume is in the range of 32 to 60% in the adsorbents disclosed in conventional Patent Documents 2 to 4 They are clearly different in comparison.

Patent Document 3 discloses an adsorbent obtained by supporting copper nitrate and aluminum nitrate on activated carbon and calcining it at 300° C. in a nitrogen atmosphere (Example: Adsorbent No. 5). . The adsorbent of Patent Document 3 is considered to have an activated carbon content of 99% by weight or more based on the supported amounts of copper and aluminum, and the activated carbon content is significantly different from that of the adsorbent of the present invention. Furthermore, in the adsorbent of Patent Document 3, although activated carbon is used as a carrier, no consideration is given to the pore size of the activated carbon or the pore volume of the adsorbent. The range of pore diameter and pore volume for improving the diffusion of hydrocarbons inside the adsorbent of the present invention is not recognized at all in the adsorbent of Patent Document 3, and this point is not recognized in the present invention. It is essentially different from the inventive adsorbent. Moreover, Patent Documents 2 and 4 do not disclose adsorbents containing copper oxide, aluminum compounds and carbon-containing compounds.

As shown in Examples 1 to 4 in Table 1 , the activated carbon contained in the adsorbent of the present invention has a large number of pores with diameters ranging from 0.1 μm to 10 μm. The fact that the activated carbon has pores with a diameter of 0.1 μm or more and 10 μm or less can be determined by directly observing the pores of the activated carbon using an electron microscope, or by measuring the pore distribution of the activated carbon by a mercury porosimetry method. can be determined by In addition, having a large number of such pores means that the pore volume of the adsorbent of the present invention in the range of the pore diameter is 0.1 mL / g or more, preferably 0.1 mL / g or more to 0.25 mL / g or less, it can be confirmed.

Thus, the adsorbent of the present invention is hydrophobic and contains activated carbon having relatively large pores (pores with a diameter of 0.1 μm or more and 10 μm or less) , so that sulfur inside the adsorbent Hydrocarbon containing compounds are easy to diffuse.

The adsorbent of the present invention has a carbon content, including activated carbon, in the range of 3% by weight or more and 15% by weight or less. This carbon content is primarily based on the activated carbon. In the adsorbent of the present invention, hydrocarbons containing sulfur compounds are diffused inside the adsorbent through a large number of relatively large pores (pores having a diameter of 0.1 μm or more and 10 μm or less) possessed by the activated carbon. easier.

If the carbon content of the adsorbent is more than the above range, the mechanical strength of the adsorbent tends to decrease and the adsorbent tends to be easily damaged, which is not preferable. On the other hand, if the carbon content is too less than the above range, the hydrocarbons containing sulfur compounds will be difficult to diffuse inside the adsorbent, which is not preferable. Further, in the adsorbent of the present invention, if the carbon content is in the range of 4% by weight or more to 10% by weight or less, carbonization containing a sulfur compound inside the adsorbent while maintaining good practical strength of the adsorbent Hydrogen can be made easier to diffuse.

The carbon content of the adsorbent of the present invention can be measured by the combustion infrared absorption method described in the Examples below. Depending on the manufacturing method of the adsorbent of the present invention, molding aids such as binders and lubricants may remain in the adsorbent, and organic compounds may be used as such molding aids. The carbon content of also includes carbon derived from organic compounds contained in such molding aids. It should be noted that organic compounds used as molding aids in the production of adsorbents are generally removed in the firing process, but in a manufacturing method that does not include a firing process, organic substances such as molding aids are removed. If a large amount of these organic substances remain, the active carbon used in the present invention has a small pore size range (diameter of 0.1 μm or more to 10 μm or less). In some cases, it will not be more than g. Therefore, the amount of carbon derived from such organic matter is naturally limited. Specifically, the carbon content including activated carbon contained in the adsorbent of the present invention is such that the pore volume of pores having a diameter of 0.1 μm or more and 10 μm or less is 0.1 mL / g or more to 0.25 mL / The amount is in the range of g or less, and the amount of organic-derived carbon is limited to an amount that does not deviate from the range of the pore volume .

The adsorbent of the present invention has a pore volume of 0.1 mL/g or more in a pore size range of 0.1 μm or more to 10 μm or less in the pore size distribution measured by mercury porosimetry. Such a range of pore diameters and a large pore volume facilitate diffusion of hydrocarbons containing sulfur compounds from the outer surface of the adsorbent into the interior. By increasing the volume of pores having relatively large diameters in this manner, the resistance to diffusion of hydrocarbons from the outer surface of the adsorbent into the interior can be reduced.

In the field of adsorbents for removing sulfur compounds contained in hydrocarbons, the volume of pores with a large diameter (macropores: 0.1 μm or more) should be small in order to increase mechanical strength. (eg, Patent Document 4), in the adsorbent of the present invention, by increasing the pore volume in this range of pore diameters, particularly in the range of 0.1 μm or more to 10 μm or less in diameter, adsorption While maintaining the mechanical strength of the agent, it facilitates the diffusion of hydrocarbons containing sulfur compounds from the outer surface of the adsorbent into the interior. Even if the pore volume in this range increases, the effect on the mechanical strength of the adsorbent is small. However, if the pore volume is too large, the mechanical strength of the adsorbent may decrease, so the pore volume is preferably in the range of 0.1 mL/g to 0.25 mL/g.

The adsorbent of the present invention preferably has a total pore volume in the range of 0.3 mL / g or more in the pore distribution measured by the mercury intrusion method described above, and 0.3 mL / g or more to 0.45 mL. /g or less is more preferable. If the total pore volume is too small, the volume of pores having a diameter of 0.1 μm or more and 10 μm or less may also decrease, which is not preferable. The ratio of the volume of pores having a diameter of 0.1 μm or more to 10 μm or less to the total pore volume is preferably in the range of 32 to 60%. If this ratio is too low, the diffusion of hydrocarbons containing sulfur compounds into the pores will be insufficient, and the removal efficiency of sulfur compounds will decrease. On the other hand, if this ratio is too high, the mechanical strength is lowered, which is not preferable.

The adsorbent of the present invention contains copper oxide. In the adsorbent of the present invention, copper oxide has the function of adsorbing and removing sulfur. For example, copper oxide has the function of adsorbing sulfur contained in carbonyl sulfide (COS), which is a type of sulfur compound and is often contained in hydrocarbons, through the reaction of CuO + COS → CuS + _CO2 . . In addition, copper oxide has a function of adsorbing sulfur contained in hydrogen sulfide ( _H2S ) through a reaction of CuO+ _H2S →CuS+ _H2O . Sulfur compounds are removed from hydrocarbons by such action of copper oxide.

The content of copper oxide contained in the adsorbent of the present invention is preferably in the range of 20% by weight to 60% by weight in terms of CuO, and is in the range of 25% by weight to 50% by weight. is more preferred. As the content of copper oxide contained in the adsorbent of the present invention increases, the amount of sulfur that the adsorbent can adsorb increases, but even if the content of copper oxide exceeds the above range, the amount of sulfur that can be adsorbed increases significantly. do not do. On the other hand, if the content of copper oxide is less than the above range, the amount of sulfur that can be adsorbed by the adsorbent is reduced, shortening the service life of the adsorbent. Moreover, since copper oxide is the most expensive component among the components constituting the adsorbent, an excessively high content of copper oxide leads to an increase in cost. Therefore, the content of copper oxide contained in the adsorbent of the present invention is preferably within the range described above.

The copper oxide contained in the adsorbent of the present invention can be identified from the X-ray diffraction pattern. The copper oxide contained in the adsorbent of the present invention has a diffraction peak attributed to copper oxide that appears in the range of 2θ = 37 to 40 ° in the X-ray diffraction pattern described above, and has a half width of 0.8 to 2 °. is preferably in the range of Copper oxide having a half-value width within the above-mentioned range has a high removal effect of sulfur compounds.

The adsorbent of the present invention contains an aluminum compound. In the present invention, the aluminum compound functions as a carrier. As the aluminum compound contained in the adsorbent of the present invention, a conventionally known aluminum compound can be used as long as it is an aluminum compound capable of fixing copper oxide. For example, it is preferably aluminum hydroxide, aluminum oxide (alumina) or a mixture thereof. When aluminum hydroxide is contained, its crystal structure is more preferably pseudo-boehmite. The crystal structure of aluminum hydroxide can be determined from the X-ray diffraction pattern.

However, since boehmite and pseudo-boehmite have similar crystal structures, it is difficult to clearly distinguish them from the X-ray diffraction pattern, but the X-ray diffraction pattern of pseudo-boehmite is broader than that of boehmite. Therefore, in the present invention, if the half width of the peak attributed to the (020) plane derived from the boehmite crystal structure is 1.0° or more, it has a pseudo-boehmite structure. judge that there is When aluminum oxide is contained, the crystal structure more preferably has one or more crystal structures selected from χ (chi), ρ (rho), and θ (theta). The crystal structure of aluminum oxide can be determined from the X-ray diffraction pattern.

When an aluminum compound having a weak acid is used as the aluminum compound contained in the adsorbent of the present invention, the function of hydrolyzing carbonyl sulfide can be imparted to the aluminum compound. Carbonyl sulfide is removed by the aforementioned reaction with copper oxide, but when carbonyl sulfide is hydrolyzed to hydrogen sulfide by an aluminum compound with a weak acid and then contacted with copper oxide for removal, the removal rate as an adsorbent is reduced. is faster than when carbonyl sulfide reacts directly with copper oxide. Therefore, the aluminum compound contained in the adsorbent of the present invention preferably has a weak acid.

Specifically, it preferably contains an aluminum compound in which the desorption amount of NH ₃ in the temperature range of 25° C. or higher and 200° C. or lower calculated by NH ₃ -TPD measurement is in the range of 0.01 mmol/g or more. . The amount of NH ₃ eliminated may be in the range of 0.01 ≤ NH ₃ eliminated amount ≤ 0.2 mmol/g, and if it is in the range of 0.01 ≤ NH ₃ eliminated amount ≤ 0.05 mmol/g It is enough. In the adsorbent of the present invention, it is expected _that the larger the amount of NH3 desorption _, the higher the hydrolysis activity of carbonyl sulfide. The hydrolytic activity is remarkably increased.

The aluminum compound contained in the adsorbent of the present invention preferably has an alkali metal or alkaline earth metal content of less than 1% by weight, particularly preferably less than 0.1% by weight, for each element. . Alkali metals or alkaline earth metals may adsorb to the acid sites of the aluminum compound contained in the adsorbent of the present invention and deactivate it, so the content thereof is preferably as small as possible.

The aluminum compounds contained in the adsorbents of the invention may each have a transition metal content of less than 1% by weight, in particular less than 0.1% by weight. Various hydrolysis catalysts for carbonyl sulfide in which transition metals such as Cr and Zn are supported on aluminum compounds are known, but the aluminum compound contained in the adsorbent of the present invention contains very little or no transition metals. Even in this case, carbonyl sulfide can be sufficiently hydrolyzed.

The content of the aluminum compound contained in the adsorbent of the present invention may be an amount suitable for supporting copper oxide. When it is below, the content of the aluminum compound contained in the adsorbent may be in the range of approximately 25% by weight or more and 77% by weight or less in terms of Al ₂ O ₃ . When the content of copper oxide contained in the adsorbent is 25% by weight or more and 50% by weight or less, the content of the aluminum compound contained in the adsorbent is approximately 35% by weight or more to 72% by weight in terms of Al ₂ O ₃ . It may be in the range of weight % or less.

The specific surface area of the adsorbent of the present invention is preferably 200 m ² /g or more, more preferably in the range of 250 m ² /g or more and 450 m ² /g or less. If the specific surface area of the adsorbent of the present invention is too low, the adsorption amount of sulfur compounds may decrease, which is not preferable. The specific surface area can be measured by conventionally known methods such as the BET multi-point method and the one-point method.

The crushing strength of the adsorbent of the present invention is preferably 20 N or more per pellet, more preferably 30 N or more. If the crushing strength of the adsorbent of the present invention is too low, the adsorbent is likely to be pulverized or disintegrated, which is not preferable. The crushing strength can be measured, for example, by the method described later in Examples.

The bulk density of the adsorbent of the present invention is preferably in the range of 0.9 kg/L or less, more preferably in the range of 0.8 kg/L or less. If the bulk density of the adsorbent is low, the impact when filling the adsorption tower with the adsorbent is reduced, so even an adsorbent with low crushing strength is less likely to break. Furthermore, since the load received by the adsorbent in the lower part of the packed bed is reduced even after the adsorbent is filled, it is possible to suppress breakage due to the own weight of the adsorbent.

The shape of the adsorbent of the present invention may be a conventionally known shape, such as a spherical shape, a columnar shape, or a similar shape. Also, the size (minimum distance of the adsorbent) should be in the range of 1 to 6 mm. For example, in the case of a cylinder with a diameter of 2 mm and a length of 5 mm, the size is 2 mm. If the size of the adsorbent is too large, the contact area between the adsorbent and the hydrocarbon becomes small, making it difficult for hydrocarbons containing sulfur compounds to diffuse from the outer surface of the adsorbent into the interior. On the other hand, if the size of the adsorbent is too small, the pressure loss increases when the hydrocarbons containing sulfur compounds are circulated, and the handleability may deteriorate.

The adsorbent of the present invention is used as an adsorbent for removing sulfur compounds contained in hydrocarbons. The adsorbent of the present invention is suitable as an adsorbent for removing carbonyl sulfide contained in C2-C6 olefins, and particularly suitable as an adsorbent for removing carbonyl sulfide contained in propylene. In addition, the adsorbent of the present invention can efficiently remove sulfur compounds contained in liquid-phase hydrocarbons that are difficult to diffuse into the adsorbent.

The adsorbent of the present invention can be suitably used in processes where the concentration of sulfur compounds contained in hydrocarbons is in the range of 0.01-30 ppmv. In addition, when the adsorbent of the present invention is used in a process containing carbonyl sulfide, the surface OH groups of the aluminum compounds contained in the adsorbent of the present invention can be used even in a process in which the amount of water is small relative to carbonyl sulfide. As a result, carbonyl sulfide can be efficiently removed. The hydrolysis of carbonyl sulfide and water proceeds by the reaction of COS+H ₂ O→CO ₂ +H ₂ S, and is a process in which the molar ratio of carbonyl sulfide and water (H ₂ O/COS) contained in hydrocarbons is less than 1. can also efficiently remove carbonyl sulfide. Further, when _the aluminum compound contained in the adsorbent of the present invention contains aluminum hydroxide having a pseudo-boehmite structure, water contained between the layers in addition to the surface OH groups can also be used for the reaction. Even when the COS molar ratio is less than 1, carbonyl sulfide can be hydrolyzed more efficiently.

The adsorbent of the present invention can efficiently remove sulfur compounds in a process in which the temperature of hydrocarbons containing sulfur compounds is in the range of -10 to 70°C.

Hereinafter, the method for producing an adsorbent of the present invention (hereinafter also referred to as the production method of the present invention) will be specifically described based on embodiments.

[Manufacturing method of the present invention]
The production method of the present invention is a method for producing an adsorbent for removing sulfur compounds contained in hydrocarbons, comprising activated carbon having pores with a diameter of 0.1 μm or more and 10 μm or less, and copper oxide , and a mixing step of obtaining a raw material mixture by mixing an aluminum compound, a molding step of molding the raw material mixture to obtain an adsorbent , and a drying step of drying the adsorbent obtained in the molding step, The carbon content including the activated carbon is 3% by weight or more and 15% by weight or less, and the volume of pores having a diameter of 0.1 μm or more and 10 μm or less is 0.1 ml/g in the pore size distribution measured by mercury porosimetry. 0.25 mL/g or more, the total pore volume is 0.3 mL/g or more and 0.45 mL/g or less, and the ratio of the pore volume to the total pore volume is 32 to 60% is a method for producing a sulfur compound adsorbent for producing an adsorbent in the range of

The production method of the present invention includes activated carbon having pores in the range of 0.1 μm or more to 10 μm or less in the pore distribution measured by mercury porosimetry and having a pore volume of 1 mL/g or more. , a mixing step of mixing copper oxide and aluminum compounds to obtain a raw material mixture.

The activated carbon used in the mixing step, which has pores ranging from 0.1 μm to 10 μm and has a pore volume of 1 mL/g or more, is equivalent to the pore volume of the adsorbent of the present invention (0.1 μm or more). 1 mL/g to 0.25 mL/g) . The carbon content including activated carbon of the adsorbent of the present invention is 3% by weight or more and 15% by weight or less, and the pore volume of the adsorbent of the present invention is within the above range (0.1 mL / g to 0.25 mL / g). It is used in an amount that is

Thus, by including activated carbon with a large pore volume in the raw material mixture, it is possible to improve the diffusion of hydrocarbons containing sulfur compounds from the outer surface of the adsorbent to the inside.

The copper oxide used in the mixing step may be obtained by firing a copper compound, or may be synthesized in an aqueous solution. When baking a copper compound, it can be obtained by baking a copper compound such as copper acetate, basic copper carbonate, or copper nitrate at 300 to 500°C. When copper oxide is synthesized in an aqueous solution, it can be obtained by heating to 50° C. or higher in a state where copper hydroxide is dispersed in the aqueous solution.

As the aluminum compound used in the mixing step, a conventionally known aluminum compound can be used as long as it is an aluminum compound capable of fixing copper oxide. For example, it is preferably aluminum hydroxide, aluminum oxide (alumina) or a mixture thereof. When aluminum hydroxide is contained, its crystal structure is more preferably pseudo-boehmite. When aluminum oxide is contained, it preferably has one or more crystal structures selected from χ (chi), ρ (rho), and θ (theta), and χ is particularly preferable.

The aluminum compound used in the mixing step is preferably an aluminum compound having a desorption amount of NH ₃ of 0.01 mmol/g or more in a temperature range of 25° C. or higher and 200° C. or lower as calculated by NH ₃ -TPD measurement. By using such an aluminum compound, a function of hydrolyzing carbonyl sulfide can be imparted to the adsorbent of the present invention. This NH ₃ elimination amount may be in the range of 0.01 mmol/g or more and 0.2 mmol/g or less, and may be in the range of 0.01 mmol/g or more and 0.05 mmol/g or less. In the _adsorbent of _the present invention, it is expected that the larger the amount of NH3 desorption, the higher the hydrolysis activity of carbonyl sulfide. , its hydrolytic activity is significantly increased.

It is known that the acidity of aluminum compounds varies depending on their crystal structure, impurities (Si, alkalis, etc.), production methods, etc. The desorption amount of NH ₃ in the temperature range of 25°C or higher to 200°C or lower calculated by NH ₃ -TPD measurement from among aluminum compounds sold as industrial raw materials or surface-treated with a weak acid is 0. Aluminum compounds in the range of 0.01 mmol/g and higher can be used.

In the production method of the present invention, the method for mixing the carbon-containing compound, copper oxide, and aluminum compound may be any method as long as these components can be uniformly mixed, and conventionally known methods can be used. For example, they can be mixed using a kneader, a mixer, or the like.

In the mixing step, each component of the carbon-containing compound, copper oxide, and aluminum compound is mixed in a ratio such that the content of each component in the finally obtained adsorbent is the content of each component in the adsorbent of the present invention. is mixed with For example, the amount of the carbon-containing compound contained in the raw material mixture is such that the carbon content is 3% by weight or more and 15% by weight or less in the produced adsorbent, and the pore distribution measured by the mercury intrusion method is The amount used is such that the volume of pores with diameters in the range of 0.1 μm or more to 10 μm or less is 0.1 mL/g or more. In addition, the amount of copper oxide contained in the raw material mixture is, for example, an amount in the range of 20% by weight to 60% by weight in terms of CuO in the manufactured adsorbent, preferably 25% by weight to 45% by weight. Amounts ranging up to weight percent are used. Furthermore, the amount of the aluminum compound contained in the raw material mixture is, for example, about 25 wt% or more to about 77 wt% when the content of copper oxide contained in the manufactured adsorbent is 20 wt% or more to 60 wt% or less. Wt% or less is used, preferably about 35 wt% or more to about 72 wt% or less when the content of copper oxide in the prepared adsorbent is 25 wt% or more to 50 wt% or less. is used.

The raw material mixture obtained after mixing may be in the form of powder or lumps, or may be made into clay by adding water during mixing. The powdery raw material mixture can be molded into a desired shape by compression molding such as tableting, and the clay-like raw material mixture can be molded into a desired shape by extrusion molding. However, using a mixing method that causes excessive pulverization may destroy the pore structure of the activated carbon , which is not preferable. Further, in the molding process described below, molding aids such as binders and lubricants may be mixed together as necessary in order to improve moldability. Furthermore, water resistance can be imparted to the adsorbent of the present invention by using a cellulose derivative.

The production method of the present invention includes a molding step of molding the raw material mixture into a desired shape. For example, a spherical, columnar or similar shape whose size (minimum distance of adsorbent) is
It is preferred to mold to a shape in the range of 1-6 mm. As a molding method, methods such as tableting molding and extrusion molding can be used. may break. Therefore, in the production method of the present invention, a production method that imposes a small load on the raw material mixture, such as extrusion molding, is preferred.

The production method of the present invention includes a drying step of drying the adsorbent obtained in the molding step. In this step, the solvent (such as moisture) contained in the adsorbent obtained in the molding step is removed. In addition, in the drying process of the present invention, heat treatment at 250° C. or higher in an air atmosphere is not performed. If heat treatment is performed at a temperature of 250° C. or higher in an air atmosphere, the activated carbon contained in the adsorbent may be burned and removed. In addition, when the activated carbon burns, carbon dioxide is generated along with intense heat generation, so the heat generation sinters the copper oxide, reducing the adsorption performance for sulfur compounds, and the generated carbon dioxide may cause the adsorbent to burst. I don't like it because there is

Hereinafter, the adsorbent of the present invention will be described in detail based on examples. Also, a comparative example is shown. In each example, the pore distribution of the carbon-containing compound (activated carbon for Examples 1 to 4, graphite for Comparative Example 2, and activated carbon for Comparative Example 3) was measured by mercury porosimetry. The carbon content and sulfur adsorption amount of the adsorbent were measured by combustion infrared absorption method.
The bulk density of the adsorbent was measured by the method described below. The specific surface area of the adsorbent was measured by the nitrogen absorption method (BET method). The mechanical strength (crushing strength) of the manufactured adsorbent was measured by the method described below.

[Example 1]
A mother liquor was prepared by dissolving 231 g of sodium hydroxide in 5.8 kg of ion-exchanged water. Next, 676 g of copper sulfate pentahydrate was dissolved in 2.6 kg of deionized water to prepare a pouring liquid. The mother liquor and the pouring liquor were each mixed while still warm to form a precipitate of copper oxide. The slurry containing the copper oxide precipitate was filtered to separate the copper oxide precipitate, and then thoroughly washed to obtain a copper oxide precipitate cake. The precipitated cake was dispersed in 4.0 kg of deionized water to obtain a copper oxide slurry. The copper oxide slurry was dried to obtain powdered copper oxide.

240 g of the copper oxide, 560 g of commercially available alumina (manufactured by UOP: VERSAL R-3) as an aluminum compound, 80 g of activated carbon (manufactured by Serachem: Hana F1-W50) as a carbon-containing compound, cellulose derivative (manufactured by Yuken Kogyo Co., Ltd.) : YB-113), 8 g of oleic acid (manufactured by Kanto Kagaku Co., Ltd.) as a lubricant, and 360 g of deionized water were charged into a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours.

Table 1 shows the results of the pore size distribution of the adsorbent obtained in Example 1 and the carbon-containing compound used as measured by mercury porosimetry. Moreover, the measurement of the pore size distribution by the mercury intrusion method was performed under the following conditions.
Measuring device: manufactured by AutoPore IV micromeritics)
Sample weight: 0.8 g (adsorbent), 0.1 g (carbon-containing compound)
Sample pretreatment: 110°C-3hr
Pressure range: 1.5-60000psia

Table 1 shows the carbon content of the adsorbent obtained in Example 1 as measured by a combustion infrared absorption method. Furthermore, Table 1 shows the sulfur adsorption amount measured for the adsorbent of Example 1 in the sulfur compound adsorption test described later. The carbon content and sulfur content were measured by the combustion infrared absorption method under the following conditions.
Measuring device: CS-230 (manufactured by LECO)
Sample shape: powder (pulverized adsorbent)
<Preparation of calibration curve>
Standard steel samples with known carbon content and sulfur content (JSS601-11, JSS243-6, and BUREAU OF ANALYSED SAMPLES LTD. BCS-CRM405/2 manufactured by the Japan Iron and Steel Federation) are used, and these standards are A calibration curve was prepared based on the average value obtained by measuring each steel sample three times and the average value obtained by measuring the blank three times. Using this calibration curve, the carbon content and sulfur content of the adsorbent of Example 1 were determined.

The copper oxide and aluminum compounds used in Example 1 were subjected to X-ray diffraction measurement. Table 1 shows the results. X-ray diffraction measurement was performed under the following conditions. As a result of analyzing the X-ray diffraction pattern obtained by this X-ray diffraction measurement using analysis software attached to the X-ray diffraction measurement apparatus, the crystal structure shown in Table 1 was assigned.
<X-ray diffraction measurement conditions>
Equipment: MiniFlex (manufactured by Rigaku Corporation)
Operation axis: 2θ/θ
Radiation source: CuKα
Measurement method: Continuous type Voltage: 40 kV
Current: 20mA
Start angle: 2θ = 20°
End angle: 2θ=70°
Sampling width: 0.020°
Scan speed: 4.000°/min

The aluminum compound used in Example 1 was subjected to NH ₃ -TPD measurement. Specifically, 0.05 g of the aforementioned aluminum compound was weighed as a sample, and set in a sample tube of an NH ₃ -TPD measuring device (manufactured by Microtrack BELL, device name: BEL-CAT A). Thereafter, heat treatment was performed at 150° C. for 60 minutes while passing an inert gas (He) through the sample tube at a flow rate of 30 ml/min. Thereafter, while maintaining the temperature of the sample tube at 100° C., a gas containing NH ₃ (NH ₃ : 5%, He: balance) was passed for 60 minutes to adsorb NH ₃ onto the sample. Thereafter, an inert gas was kept flowing through the sample tube at a flow rate of 30 ml/min for 60 minutes. Next, while keeping the holding temperature at 100° C. and the flow rate of the inert gas at 30 ml/min, water vapor was introduced into the test tube for 30 minutes to remove the physically adsorbed NH ₃ . The introduction of water vapor was stopped, and the temperature was maintained at 100° C. and the inert gas flow rate was 30 ml/min for 30 minutes. Next, the temperature was raised to 700° C. at a temperature elevation rate of 10° C./min and held for 10 minutes. At this time, NH ₃ desorbed from the sample was measured using a quadrupole gravimetric analyzer (Q-Mass). From the data obtained by this measurement, the amount of _NH3 desorbed when the temperature of the sample tube was between 25°C and 200°C was calculated. The amount of NH ₃ desorption in the following temperature range was calculated. Table 1 shows the results.

Composition analysis was performed on the adsorbent obtained in Example 1. Table 1 shows the results. Moreover, the composition analysis was performed under the following conditions.
<Method for measuring composition>
After pulverizing the adsorbent into powder, the sample was placed in a pressure-molding ring and pressure-molded for 3 minutes at a molding pressure of 30 MPa. This molded sample was set in a fluorescent X-ray analyzer (ZSX100e manufactured by Rigaku Co., Ltd.) and measured by order (semi-quantitative) analysis.

The crushing strength of the adsorbent obtained in Example 1 was measured. Table 1 shows the results. Moreover, the composition analysis was performed under the following conditions.
Measuring device: crushing strength meter (manufactured by Instron, model 3365)
Number of measurements: 10 times (this average value was used as the measured value)
Measurement direction: The thinnest surface (the surface with the lowest crushing strength) was measured in the vertical, horizontal, and height directions.

The bulk density of the adsorbent obtained in Example 1 was measured. Table 1 shows the results. The bulk density was measured under the following conditions.
<Method for measuring bulk density>
The adsorbent was filled into a 1 L cylindrical vessel by gravity using a fixed funnel. The heaped portion of the container (the portion where the adsorbent overflowed from the container) was scraped off with a scraping spatula, and the weight of the adsorbent equivalent to 1 L was accurately weighed for measurement. This operation was repeated three times, and the average value was taken as the bulk density. No tapping or the like was performed when filling the adsorbent.

The specific surface area of the adsorbent obtained in Example 1 was measured. Table 1 shows the results. The specific surface area was measured under the following conditions.
<Method for measuring specific surface area>
Perform pretreatment under nitrogen flow, set in a fully automatic specific surface area measuring device (manufactured by Mountec, model: MacsorbHM model-1220), and use the nitrogen adsorption method (BET method) to determine BET1 from the amount of nitrogen desorption. The specific surface area was calculated by the point method. Specifically, 0.1 g of the sample is filled into a measurement cell, pretreated at 250 ° C.-40 min under nitrogen flow, and a nitrogen mixed gas (30% nitrogen and 70% helium in volume fraction). The temperature of liquid nitrogen was maintained in an air stream of 100 rpm, and nitrogen was allowed to equilibrate to the sample. Next, the temperature of the sample was gradually raised to room temperature while the mixed gas was flowing, and the amount of nitrogen desorbed during this time was detected by TCD. Finally, a pulse of 1 cc of pure nitrogen was passed through, and the specific surface area was calculated from the ratio to the above nitrogen desorption amount.

The adsorbent obtained in Example 1 was subjected to a carbonyl sulfide adsorption test. Specifically, a reaction tube with an inner diameter of 1 cm was filled with a sample so that the layer height of the adsorbent was 8 cm, and then heat-treated at 170° C. for 1 hour while nitrogen was circulated. After standing to cool, a raw material liquid (COS: 10 wtppm, 1-hexene: balance) was supplied at a rate of 5.0 g/min at room temperature. After circulating the raw material liquid for 120 minutes, a sample was taken out and analyzed for sulfur adsorption with a carbon-sulfur analyzer.

Each 5 g of the adsorbent of Example 1 was immersed in 1 L of a COS/1-hexene solution (COS concentration: 200 wtppm) at room temperature for 28 days. After the adsorbent was taken out and dried, the distribution of sulfur inside the adsorbent was observed by EDS analysis. The results are shown in FIG.

[Example 2]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 560 g of commercially available alumina (manufactured by UOP: VERSAL R-3) as an aluminum compound, 40 g of activated carbon (manufactured by Futamura Chemical Co., Ltd.: Taiko M) as a carbon-containing compound, and a cellulose derivative (manufactured by Yuken Industry: YB-113C), 8 g of oleic acid (manufactured by Kanto Kagaku Co., Ltd.) as a lubricant, and 429 g of deionized water were charged in a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.

[Example 3]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 40 g of activated carbon (manufactured by Futamura Chemical Co., Ltd.: Taiko S) as a carbon-containing compound, 560 g of commercially available alumina (manufactured by UOP: VERSAL R-3) as an aluminum compound, and a cellulose derivative (manufactured by Yuken Kogyo Co., Ltd.: YB-113C), 8 g of oleic acid (manufactured by Kanto Kagaku Co., Ltd.) as a lubricant, and 439 g of deionized water were charged in a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.

[Example 4]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 40 g of activated carbon (manufactured by Futamura Chemical Co., Ltd.: Taiko Y) as a carbon-containing compound, 560 g of commercially available alumina (manufactured by UOP: VERSAL R-3) as an aluminum compound, and a cellulose derivative (manufactured by Yuken Kogyo Co., Ltd.: YB-113C), 8 g of oleic acid (manufactured by Kanto Kagaku Co., Ltd.) as a lubricant, and 426 g of deionized water were charged in a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.

[Comparative Example 1]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 560 g of commercially available alumina (manufactured by UOP: VERSAL R-3) as a carrier, 16 g of cellulose derivative (manufactured by Yuken Kogyo: YB-113C), and oleic acid (manufactured by Kanto Kagaku) as a lubricant. and 320 g of ion-exchanged water were charged into a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. The adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.
Each 5 g of the adsorbent of Comparative Example 1 was treated in the same manner as in Example 1, and the distribution of sulfur inside the adsorbent was observed by EDS analysis. The results are shown in FIG.

[Comparative Example 2]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 40 g of graphite (manufactured by East Japan Carbon Co., Ltd.: B-50) as a carbon-containing compound, 560 g of commercially available alumina (manufactured by UOP: VERSAL R-3) as an aluminum compound, a cellulose derivative (manufactured by Yuken Kogyo Co., Ltd. : YB-113C), 8 g of oleic acid (manufactured by Kanto Kagaku Co., Ltd.) as a lubricant, and 320 g of deionized water were charged into a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.

[Comparative Example 3]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 80 g of activated carbon (manufactured by Kuraray Co., Ltd.: Kuraray Coal PK-W5N) as a carbon-containing compound, 560 g of commercially available alumina (manufactured by UOP Co., Ltd.: VERSAL R-3) as an aluminum compound, cellulose derivative (Yuken Kogyo Co., Ltd.) YB-113C (manufactured by YB-113C), 8 g of oleic acid (manufactured by Kanto Kagaku Co., Ltd.) as a lubricant, and 322 g of deionized water were charged in a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.

[Comparative Example 4]
A powdery copper oxide was obtained in the same manner as in Example 1. 240 g of this copper oxide, 560 g of commercially available aluminum hydroxide (manufactured by Showa Denko: H-32) as an aluminum compound, 16 g of cellulose derivative (manufactured by Yuken Kogyo: YB-113C), and oleic acid (Kanto Chemical) as a lubricant Co., Ltd.) and 250 g of deionized water were charged into a mixer and uniformly mixed to obtain a raw material mixture.

This raw material mixture was charged into an extruder, and extruded into a cylindrical shape having a length of 3 to 5 mm using a die having a diameter of 1.65 mmφ and a thickness of 4 mm to obtain an adsorbent. This adsorbent was dried in an electric dryer at a temperature of 120° C. for 16 hours. This adsorbent was evaluated and analyzed in the same manner as in Example 1. Table 1 shows the results.

As shown in Table 1, in any of the adsorbents of Examples 1 to 4, the activated carbon contains pores with a diameter of 0.1 μm or more and 10 μm or less, and the carbon content of the adsorbent is 3% by weight or more. It is 15% by weight or less, and in the pore distribution measured by mercury porosimetry, the volume of pores having a diameter of 0.1 μm or more and 10 μm or less is 0.1 mL/g or more. Therefore, in the carbonyl sulfide adsorption test, the raw material liquid (hydrocarbon containing carbonyl sulfide) easily diffuses into the adsorbent, resulting in a high sulfur adsorption amount. This can also be confirmed from the fact that sulfur is adsorbed up to the center of the adsorbent in FIG. 1, which shows the sulfur distribution inside the adsorbent after the adsorption test for the adsorbent of Example 1.

On the other hand, in the adsorbents of Comparative Examples 1 to 4, the pore volume in the range of 0.1 μm or more to 10 μm or less in diameter is less than 0.1 mL / g in the pore distribution measured by the mercury intrusion method. , In the adsorption test of carbonyl sulfide, the raw material liquid (hydrocarbon containing carbonyl sulfide) is difficult to diffuse inside the adsorbent. This can also be confirmed from the fact that not much sulfur is adsorbed in the central part of the adsorbent in FIG. 2, which shows the sulfur distribution inside the adsorbent after the adsorption test for the adsorbent of Comparative Example 1.

The pore distributions of the activated carbons of Examples 1 to 4, the graphite of Comparative Example 2, and the activated carbon of Comparative Example 3 are shown in the graph of FIG. Also, the pore distributions of the adsorbents of Examples 1 to 4 and Comparative Examples 1 to 3 are shown in the graph of FIG. As shown in FIG. 3, the pores of the activated carbon used for the adsorbents of Examples 1 to 4 have pores with a diameter of 0.1 μm or more and 10 μm or less, and the pore volume is , and the pore volume in the range of 0.1 μm or more to 10 μm or less in diameter of the adsorbent using these is also remarkably large.

Claims (2)

An adsorbent for removing sulfur compounds contained in hydrocarbons,
Contains copper oxide, aluminum compounds, and activated carbon,
The activated carbon has pores with a diameter of 0.1 μm or more and 10 μm or less,
The carbon content including the activated carbon is 3% by weight or more and 15% by weight or less,
In the pore distribution measured by mercury porosimetry,
The volume of pores with a diameter of 0.1 μm or more and 10 μm or less is 0.1 mL/g or more and 0.25 mL/g or less, and the total pore volume is 0.3 mL/g or more and 0.45 mL/g or less. can be,
A sulfur compound adsorbent, wherein the ratio of said pore volume to said total pore volume is in the range of 32 to 60%. A method for producing an adsorbent for removing sulfur compounds contained in hydrocarbons, comprising:
A mixing step of obtaining a raw material mixture by mixing activated carbon having pores with a diameter of 0.1 μm or more to 10 μm or less, copper oxide, and an aluminum compound,
A molding step of molding the raw material mixture to obtain an adsorbent ,
including a drying step of drying the adsorbent obtained in the molding step,
The carbon content including the activated carbon is 3% by weight or more and 15% by weight or less,
According to the pore size distribution measured by mercury porosimetry , the volume of pores with a diameter of 0.1 μm or more and 10 μm or less is 0.1 mL/g or more and 0.25 mL/g or less, and the total pore volume is 0.3 mL. /g or more to 0.45 mL/g or less, and the ratio of the pore volume to the total pore volume is in the range of 32 to 60%.

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