RU2215571C2 - Desulfurizer and a method for preparation thereof - Google Patents

Abstract

FIELD: purification methods. SUBSTANCE: high-efficiency desulfurizer capable of removing hydrogen sulfide from gaseous and liquid products includes Ca₂Fe₂O₅ as active component and is prepared as follows. Powder containing ferric oxide and/or ferric hydroxide, and/or ferric nitrate as principal components is mixed with powder containing calcium oxide and/or calcium hydroxide, and/or calcium bicarbonate, and/or calcium carbonate with iron-to-calcium molar ratio from 1:1 to 1:5. To resultant mixture is added water and mixture is then stirred, molded, dried, baked in oxidative atmosphere at 700 to 1100 C during 0.5 to 24 h. Final product is obtained after pulverizing a small amount of water onto cooled product. EFFECT: increased sulfur absorption capacity. 23 cl, 2 dwg, 5 tbl, 12 ex

Description

Field of Invention
This invention relates to a desulfurizer capable of removing hydrogen sulfide (H ₂ S) from gaseous or liquid products and to a method for its preparation. It relates, in particular, to a highly efficient desulfurizing agent comprising Ca ₂ Fe ₂ O ₅ as an active component, and to a method for preparing it.

Justification of the invention
The presence of hydrogen sulfide (H ₂ S) during the production of chemical products from coal or oil often causes poisoning and thereby deactivation of the catalysts used in the subsequent technological stage. A large amount of industrial wastewater or exhaust gas also contains a significant amount of hydrogen sulfide (H ₂ S), which can lead to environmental pollution or poisoning of people or animals if they are released without treatment. Previously known desulfurizers include activated carbon, zinc oxide or ferric oxide as main components. Zinc oxide, being a desulfurizer at high temperatures, was usually used at a temperature in the range from 200 to 500 ^o C in order to achieve good desulfurization results. Desulfurization at normal temperature, as described in a number of patent documents, cannot give the desired effect if the temperature drops below 80 ^o C. In this case, the sulfur capacity is extremely low (below 9 wt.%). Another known desulfurizer, including ferric oxide as its main component, can only be used in such a case as preliminary (coarse) desulfurization, or can be used in combination with other agents, since it limits the conditions of applicability in terms of temperature and space velocity and has lower reactivity and lower sulfur capacity. Thus, the aforementioned desulfurization agent cannot provide the desired result.

Chinese patent application CN 1067828A describes a new process for fine desulfurization of organic or inorganic sulfides at normal temperature. The method comprises the steps of desulfurizing the process gas by using modified activated carbon or iron oxide at normal temperature and then hydrolyzing and absorbing the sulfide at a temperature of 30-120 ^{° C.} under normal pressure by using a catalyst capable of hydrolyzing the organic sulfide at normal temperature, and optionally re-desulfurizing process gas by using modified activated carbon or ferric oxide at normal rate Rural. In this method, ferric oxide, if used as a desulfurizer, is an industrial product under the trademarks TG-1, SN-1 and ET-1. Details of the composition of the desulfurizer and the method of its preparation are not described in this description. It is said that the desulphurization accuracy of this method is 0.1 ppm, but the method for evaluating the desulphurization accuracy is not disclosed. In addition, the sulfur capacity of the desulfurizer is not described.

Chinese patent application CN 1068356A describes a two-stage process for the desulfurization of coke oven gas at elevated temperature. The specified method includes the first stage of preliminary desulfurization and the second stage of desulfurization at elevated temperature, where the second stage is carried out at 650 ^o C. The desulfurizer used in the first stage is an iron oxide desulfurizer obtained by mixing iron-slurry waste from a steel mill with 4- 15% calcium oxide and 10-40% bentonite and firing the mixture at an elevated temperature of 800-1000 ^o C. the Desulfurization efficiency of the desulfurizer used in the first stage of desulfurization, more less than 90%, while the sulfur capacity of the desulfurizer is 8%. The applicant does not indicate in the description either the temperature in the first stage of desulfurization, nor the firing atmosphere of the desulfurizer. The desulfurizer used in the second stage is a zinc-iron desulfurizer obtained by mixing ferric oxide and zinc oxide with 10-40% bentonite and then firing the resulting mixture at an elevated temperature of 800-1000 ^o C. The desulfurization efficiency of the zinc-iron desulfurizer more than 90%, while the sulfur capacity of the desulfurizer is 8%. The composition of the iron-sludge waste from a steel mill is complex and changes when the raw materials come from different technological operations. In addition, iron-slurry waste contains many impurities, such as aluminum, phosphorus, sulfur, manganese, carbon, etc., or, possibly, iron. Since a detailed description of its composition is not included in the description, it is impossible to estimate the iron content in the iron-sludge waste. However, it is known from the description of said patent application that such an iron oxide desulfurizer can only be used for crude desulfurization. In addition, Chinese patent application CN 1094331A describes a zinc oxide desulfurizer that can be used at normal temperature and a method for preparing it.

 The performance of the desulfurizer depends mainly on factors such as sulfur capacity, accuracy of desulfurization and the temperature at which it can be used. The higher the sulfur capacity and the desulphurization accuracy becomes, the better the desulfurization performance will be. The desulfurizer used in CN 1067828A is unsatisfactory in terms of the accuracy of desulfurization, while the desulfurizers used in CN 1068356A do not have sufficient sulfur capacity and accuracy of desulfurization, which requires two stages to reduce sulfur content to 1ppm. To date, no known document has described a desulfurizer with a sulfur capacity of more than 20%.

DETAILED DESCRIPTION OF THE INVENTION
An object of the present invention is to provide a desulfurizer capable of removing hydrogen sulfide (H ₂ S) from gaseous or liquid products at a relatively low temperature. The specified desulfurizer has a high sulfur capacity, high desulfurization accuracy and a high reaction rate.

Another objective of the present invention is a method of preparing a desulfurizer with a high sulfur capacity and high desulfurization accuracy. The desulfurizer includes Ca ₂ Fe ₂ O ₅ as an active component and can be used at low temperature in gaseous or liquid products.

In accordance with one aspect of the invention, there is provided a desulfurizer for removing hydrogen sulfide from gaseous or liquid materials, comprising Ca ₂ Fe ₂ 0 ₅ as an active component.

According to a preferred embodiment of the invention, the amount of the active component Ca ₂ Fe ₂ O ₅ is more than 40% based on the total weight of said desulfurizer.

According to another preferred embodiment of the invention, the amount of said active component Ca ₂ Fe ₃ 0 ₅ is 70-90% based on the total weight of said desulfurizer.

 According to yet another preferred embodiment, the desulfurizer comprises less than 20% water based on the total weight of the desulfurizer.

 In accordance with another preferred embodiment of the invention, the desulfurizer comprises less than 40% based on the total weight of said calcium oxide and / or calcium hydroxide desulfurizer and / or auxiliary structural agents, such as bentonite.

According to another preferred embodiment of the invention, the desulfurizer has a specific surface area of 1.8 to 3 m ² / g.

 According to another preferred embodiment, the desulfurization porosity is from 50 to 65%.

According to another preferred embodiment, the apparent density of the desulfurizer is 1.0-1.5 g / cm ³ .

According to another preferred embodiment of the invention, a desulfurizer is provided for removing hydrogen sulfide from a gaseous or liquid material, comprising, based on the total weight of the desulfurizer, more than 40% Ca ₂ Fe ₂ 0 ₅ as an active component, less than 20% water and less than 40% calcium oxide and / or calcium hydroxide and / or structural auxiliary agents, such as bentonite.

In accordance with another aspect of the invention, there is provided a method for producing a desulfurizer, comprising the following steps:
a) mixing a powder comprising ferric oxide and / or ferric hydroxide and / or ferric nitrate as a main component with another powder comprising calcium oxide and / or calcium hydroxide and / or calcium bicarbonate and / or calcium carbonate, where the molar ratio of iron to calcium is from 1: 1 to 1: 5;
b) adding water to the resulting mixture and then treating it by stirring, molding and drying;
c) firing the product obtained in stage b) in an oxidizing atmosphere at a temperature of from 700 to 1100 ^o C for from 0.5 to 24 hours;
d) cooling the product obtained in step c), followed by uniformly spraying a small amount of water on it to obtain the final product of a desulfurizer.

 In step a), various structural auxiliary agents and pore-forming materials can be added. Structural auxiliary agents suitable for the present invention include silica, alumina, bentonite, kaolin, etc. The most suitable pore-forming materials include coal powder, starch and cellulose.

In principle, in step a), iron-containing compounds other than ferric oxide or ferric hydroxide, for example ferric nitrate, etc., and calcium-containing compounds other than calcium oxide or calcium hydroxide, for example calcium carbonate and calcium bicarbonate can be used. . However, iron-containing compounds such as ferric oxide or hydroxide, and calcium-containing compounds such as calcium oxide or hydroxide are preferred. In all cases, the molar ratio of iron to calcium should be from 1: 1 to 1: 5 and a specific structure of Ca ₂ Fe ₂ 0 ₅ should be formed.

 In principle, in step d), an aqueous solution containing some substances, such as a solution of hydroxide or chloride of an alkali metal or alkaline earth metal, for example sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium nitrate, potassium nitrate, calcium nitrate, chloride can be used instead of water sodium, potassium chloride and calcium chloride, etc., provided that these substances do not affect the operation of the desulfurizer.

 In step b), the mixture can be molded in various suitable forms, such as a rod, ball, granule or honeycomb.

The final finished desulfurizer of the present invention (in the form of rods) has a tensile strength of more than 110 N / cm, specific surface area of 1.8-3 m ² / g, porosity of 50-65% and an apparent density of 1.0-1.5 g / cm ³ .

In a preferred embodiment of the method according to the invention, the calcination temperature is between 850 and 950 ^{° C.} , and said calcination time is from 2 to 3 hours.

In another preferred embodiment of the method according to the invention, the firing temperature is between 950 and 1050 ^o C, and the specified firing time is from 0.5 to 1.5 hours

In a preferred embodiment of the method according to the invention, said drying is carried out at a temperature between 100 and 200 ^{° C.} for a period of 1-4 hours.

In another preferred embodiment of the method of the invention, the powders used in step a) are Fe ₂ O ₃ and CaO powder, respectively, and the molar ratio of iron to calcium is from 1: 1 to 1: 2, preferably 2: 3.

In another preferred embodiment of the method according to the invention, the powders used in step a) are Fe ₂ O ₃ and Ca (HCO ₃ ) ₂ powder, respectively, and the molar ratio of iron to calcium is from 1: 1 to 1: 2, preferably 2: 3.

In another preferred embodiment of the method of the invention, the powders used in step a) are Fe ₂ 0 ₃ and Ca (OH) ₂ powder, respectively, and the molar ratio of iron to calcium is from 1: 1 to 1: 2, preferably 2: 3.

 In a preferred embodiment of the method of the invention, the powders used in step a) are Fe (OH) s powder and CaO powder, respectively, and the molar ratio of iron to calcium is from 1: 1 to 1: 2, preferably 2: 3.

 In another preferred embodiment of the method according to the invention, in step a), less than 5-30%, based on the total weight of said kaolin and / or bentonite desulfurizer, is added as a structural auxiliary agent.

 In yet another preferred embodiment of the method of the invention, in step a), a small amount of coal powder or starch is added as a pore-forming material.

The final finished desulfurizer of the present invention can be widely used in the desulfurization of gases containing hydrogen sulfide (H ₂ S), such as coke oven gas, hydrogen, synthesis gas, ammonia gas, gaseous hydrocarbons, etc., and also used in the desulfurization liquid masses, such as kerosene, gasoline, cyclohexane, etc. When a desulfurizer is used in a temperature range of 5-90 ^{° C.} with a gas volumetric velocity of less than 10,000 h ⁻¹ or hourly volumetric liquid velocity of less than 10 h ⁻¹ , the sulfur capacity before breakthrough is more than 20% (weight / weight). The desulfurizer can be regenerated for reuse by blowing air through it.

Brief Description of the Drawings
Figure 1 presents the X-ray diffraction pattern for the desulfurizer obtained in Example 1. When compared with standard X-ray diffraction data (JCPDS chip), the data in Figure 1 show that the main component of the desulfurizer is Ca ₂ Fe ₂ 0 ₅ .

Figure 2 presents an X-ray diffraction pattern for the desulfurizer obtained in Example 1, which was used to remove H ₂ S and was brought to a breakthrough. When compared with standard X-ray diffraction data (JCPDS chip), the data in figure 2 show that the main component is a mixture of Fe ₇ S ₈ and FeS.

BEST MODE FOR CARRYING OUT THE INVENTION
EXAMPLE 1
Desulfurizer A was prepared by the following steps:
a) weighed 42 g of Fe ₂ O ₃ powder and 58 g of CaO powder, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 2
Desulfurizer B was prepared by the following steps:
a) weighed 42 g of Fe ₂ O ₃ powder and 58 g of CaO powder, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 1000 ^o C for 2 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 3
Desulfurizer C was prepared by the following steps:
a) weighed 35 g of Fe ₂ O ₃ powder and 65 g of Ca (OH) ₂ powder, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 4
Desulfurizer D was prepared by the following steps:
a) weighed 32.5 g of Fe (OH) ₃ powder and 67.5 g of Ca (OH) ₂ powder, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 5
Desulfurizer E was prepared by the following steps:
a) weighed 49 g of Fe ₂ O ₃ powder and 51 g of CaO powder, respectively, and mixed them;
b) water was added to the resulting mixture, and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 6
The desulfurizer F was prepared by the following steps:
a) weighed 37 g of Fe ₂ O ₃ powder, 43 g of Ca (OH) ₂ powder and 20 g of bentonite, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 7
The desulfurizer G was prepared by the following steps:
a) weighed 35 g of Fe ₂ O ₃ powder, 65 g of Ca (OH) ₂ powder and 1 g of coal powder, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 8
Desulfurizer N was prepared by the following steps:
a) 30.5 g of Fe ₂ 0 ₃ powder, 49.5 g of Ca (OH) powder ₂ , 1 g of coal powder and 20 g of bentonite were weighed, respectively, and mixed;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 900 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 9
Desulfurizer 1 was prepared by the following steps:
a) weighed 29.6 g of Fe ₂ O ₃ powder, 27.5 g of Ca (OH) ₂ powder, 32.9 g of Ca (HCO ₃ ) ₂ powder and 10 g of bentonite, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 150 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 1000 ^o C for 2 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 10
Desulfurizer J was prepared by the following steps:
a) weighed 46.2 g of Fe ₂ O ₃ powder, 21.4 g of Ca (OH) ₂ , 32.4 g of CaO powder and 2 g of coal powder, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 1000 ^o C for 2 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 11
Desulfurizer K was prepared by the following steps:
a) weighed 41.7 g of Fe ₂ O ₃ powder, 50 g of CaO powder, 8.3 g of Ca (HCO ₃ ) ₂ powder and 20 g of bentonite, respectively, and mixed them;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 2 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 950 ^o C for 3 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 10 g of water on it.

EXAMPLE 12
The desulfurizer L was prepared by the following steps:
a) weighed 25.6 g of Fe ₂ O ₃ powder, 11.9 g of Ca (OH) ₂ powder, 9.0 g of CaO powder, 8.3 g of Ca (HCO ₃ ) ₂ powder and 30 g of bentonite, respectively, and mixed them ;
b) water was added to the resulting mixture and then it was stirred, kneaded and extruded in order to obtain a rod-shaped product, dried at a temperature of about 100 ^{° C.} for 3 hours;
c) calcined the product obtained in stage b) in an oxidizing atmosphere at a temperature of 1000 ^o C for 2 hours;
d) the product obtained in step c) was cooled, followed by uniformly spraying about 15 g of water on it.

Evaluation of the desulfurizer was carried out using a gas with a content of 5000 ppm H ₂ S under the following conditions: 5 g of the desulfurizer of examples 1 to 12, respectively, normal temperature and pressure, space velocity of 1000 h ^-1 . H ₂ S content was determined using a WLSP-852 Trace Sulfur Analyzer. The specified device is produced by the South-West Research Institute of Chemical Industry. The lowest detectable H ₂ S content can reach 0.02 ppm.

EXPERIENCE 1
The experiment was carried out under the following conditions: 1) process temperature: 20 ^o C; 2) pressure: atmospheric pressure; 3) H ₂ S concentration: 5000 ppm in H ₂ ; 4) space velocity: 1000 h ^-1 . The results of the experiments are shown in table 1.

H ₂ S content was determined using a WLSP-852 Trace Sulfur Analyzer. The specified device is manufactured by the South-West Research Institute of Chemical Industry of the Ministry of Chemical Industry. The lowest detectable H ₂ S content can reach 0.02 ppm.

 The desulfurizer of the present invention has a better desulfurization effect and a higher sulfur capacity than the commercially available ZnO desulfurizer. Comparison of these two products shows experience 2.

EXPERIENCE 2
This experiment was carried out using the desulfurizer of Example 1 of the present invention and commercially available ZnO (normal temperature), respectively, under conditions of H ₂ S concentration of 2000 ppm in H ₂ and a varying space velocity: 1500 h ^-1 , 3000 h ^-1 , 4500 h ^{- 1} , 6000 h ^-1 . The result of comparing the sulfur capacity before the breakthrough of the two indicated desulfurizers at different space velocities is shown in Table 2.

EXPERIENCE 3
This experiment was carried out using two series-connected reactors to check the sulfur capacity. The operating conditions in each reactor were as follows: 50 g of a desulfurizer, space velocity of 1500 h ^-1 , the starting material was synthesis gas, the content of H ₂ S: 5000 ppm, temperature: 20 ^o C, pressure - atmospheric. The content of H ₂ S in the desulfurized gas is controlled at a concentration lower than 1,0 ppm. When the indicated concentration became higher than 1.0 ppm, it was believed that there was a breakthrough of the desulfurizer, and thus the experiment came to an end. Then, in a conventional manner, the reactor capacity was determined by sulfur. In this experiment, the desulfurizer obtained in Example 1 and ZnO were used to remove H ₂ S. Sulfur capacity data are shown in table 3.

EXPERIENCE 4
This experiment was carried out to remove H ₂ S present in liquid materials with different contents of H ₂ S using the desulfurizer of Example 1 of the present invention, under conditions: 20 ^{° C.} , normal pressure, hourly space velocity of the liquid 1 h ^-1 . The results of the experiment are shown in table 4.

EXPERIENCE 5
Experiment 4 was repeated using the same conditions, except that only hydrogenated dark-colored gasoline was selected as the starting material and the hourly space velocity of the liquid was 5 h ^-1 .

The samples used in experiments 4 and 5 were obtained by passing a fixed amount of standard H ₂ S gas through purified liquid products, as a result of which the composition was adjusted to the requirements of the experiment. Hydrogenated dark-colored gasoline with a content of 531.5 ppm H ₂ S was the real product of a refinery.

Industrial Applicability
The present invention relates to a desulfurizer capable of removing hydrogen sulfide (H ₂ S) from gaseous or liquid materials, which includes Ca ₂ Fe ₂ 0 ₅ as an active component, and to a method for producing it. A desulfurizer is obtained by firing at high temperature a mixture of a powder containing ferric oxide and / or ferric hydroxide and / or ferric nitrate as its main component, with another powder including calcium oxide and / or calcium hydroxide, and / or bicarbonate calcium, and / or calcium carbonate. Such a desulfurizer can be widely used in the desulfurization of hydrogen sulfide (H ₂ S) gases, such as coke oven gas, synthesis gas, ammonia gas, hydrogen, etc., and also in the sulfurization of liquid masses, such as kerosene, gasoline, cyclohexane etc. As a result of industrial applications, it was confirmed that the desulfurizer of the present invention has the following advantages: sulfur capacity before breakthrough — above 20%, wide temperature and pressure range during use, high efficiency, high reaction rate, and high desulfurization accuracy.

The desulfurizer of the present invention has a specific structure of Ca ₂ Fe ₂ O ₅ , the pattern of its x-ray diffraction shows that such a structure is formed due to the specific ratio of calcium to iron (Ca: Fe) and firing temperature. Suitable firing temperature varies depending on the ratio of calcium to iron (Ca: Fe).

Compared with the technology described in Chinese patent application CN 1067828A, the present invention differs from the foregoing in the following aspects: the ratio of calcium to iron (Ca: Fe) is specific; the material does not contain elemental iron; the mixture is subjected to stirring, molding and drying before firing; firing is carried out in an oxidizing atmosphere; the desulfurization temperature used here is relatively low and the sulfur capacity is high; desulfurizer provides high accuracy of desulfurization to breakthrough; only one step is required to completely remove hydrogen sulfide (H ₂ S); a desulfurizer can be used for either gaseous or liquid products.

Claims (23)

1. Desulfurization agent for removing hydrogen sulfide from gaseous or liquid materials, including Ca ₂ Fe ₂ O ₅ as an active component. 2. The desulfurizer according to claim 1, wherein the amount of said active component Ca ₂ Fe ₂ O ₅ is more than 40% based on the total weight of said desulfurizer. 3. The desulfurizer according to claim 2, wherein the amount of said active component Ca ₂ Fe ₂ O ₅ is 70-90%, based on the total weight of said desulfurizer.  4. The desulfurizer according to claim 2, where it includes less than 20% water, based on the total weight of the specified desulfurizer.  5. The desulfurizer according to claim 2, where it comprises less than 40% based on the total weight of said desulfurizer of calcium oxide and / or calcium hydroxide and / or auxiliary structural agents, such as bentonite. 6. The desulfurizer according to claim 2, wherein the specific surface area is 1.8-3 m ² / g.  7. The desulfurizer according to claim 2, in which the porosity is 50-65%. 8. The desulfurizer according to claim 2, in which the apparent density is 1.0-1.5 g / cm ³ . 9. A method of producing a desulfurizer according to any one of paragraphs. 1-8, comprising the following steps: a) mixing a powder comprising ferric oxide and / or ferric hydroxide and / or ferric nitrate as a main component with another powder comprising calcium oxide and / or calcium hydroxide, and / or calcium bicarbonate and / or calcium carbonate, where the molar ratio of iron to calcium is from 1: 1 to 1: 5; b) adding water to the resulting mixture and then treating it by stirring, molding and drying; c) firing the product obtained in stage b) in an oxidizing atmosphere at 700-1100 ^o C for 0.5-24 hours; d) cooling the product obtained in step c), followed by uniformly spraying a small amount of water on it to obtain the final product of a desulfurizer. 10. The method according to p. 9, in which the specified firing temperature is between 850 and 950 ^o C and the specified firing time is 2-3 hours 11. The method according to p. 9, in which the specified firing temperature is between 950 and 1050 ^o C and the specified firing time is 0.5-1.5 hours 12. The method according to p. 9, in which the specified drying is carried out at a temperature between 100 and 200 ^o C for 1-4 hours 13. The method according to p. 9, in which the powders used in stage a) are Fe ₂ O ₃ powder and CaO powder, respectively, and the molar ratio of iron to calcium is 1: 1-1: 2.  14. The method of claim 13, wherein said molar ratio is 2: 3. 15. The method according to p. 9, in which the powders used in stage a) are Fe ₂ O ₃ powder and Ca (HCO ₃ ) ₂ powder, respectively, and the molar ratio of iron to calcium is 1: 1-1: 2.  16. The method of claim 15, wherein said molar ratio is 2: 3. 17. The method according to claim 9, in which the powders used in stage a) are Fe ₂ O ₃ powder and Ca (OH) ₂ powder, respectively, and the molar ratio of iron to calcium is 1: 1-1: 2.  18. The method of claim 17, wherein said molar ratio is 2: 3. 19. The method according to p. 9, in which the powders used in stage a) are Fe (OH) ₃ powder and CaO powder, respectively, and the molar ratio of iron to calcium is 1: 1-1: 2.  20. The method of claim 19, wherein said molar ratio is 2: 3.  21. The method according to p. 9, in which at the stage a) add less than 5-30% based on the total weight of the specified desulfurizer kaolin and / or bentonite as a structural auxiliary agent.  22. The method according to p. 9, in which at the stage a) add a small amount of coal powder or starch as a pore-forming material. 23. A desulfurizer for removing hydrogen sulfide from gaseous or liquid materials, including, based on the total weight of said desulfurizer, more than 40% Ca ₂ Fe ₂ O ₅ as an active component, less than 20% water and less than 40% calcium oxide and / or calcium hydroxide , and / or auxiliary structural agents, such as bentonite.

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