Reforming hydrogen dechlorination agent, its preparation and application

Abstract

The application discloses a preparation method of a reforming hydrogen dechlorination agent, which comprises the following steps: (1) drying petroleum coke, and then mixing the petroleum coke with an alkaline earth metal peroxide to perform pretreatment; (2) mixing the mixture after the pretreatment in step (1) with an alkali, and performing high-temperature treatment under an inert atmosphere condition, and then performing washing and drying; and (3) performing oxidation modification on the dry substance obtained in step (2), and then performing washing and drying to obtain the dechlorination agent. The dechlorination agent can reduce the content of chlorides in reforming hydrogen to below 0.5 mg / L, and has a high breakthrough chlorine capacity.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of petrochemical industry, in particular to a reforming hydrogen dechlorination agent, a preparation method thereof and application thereof in a reforming hydrogen dechlorination process. BACKGROUND

[0002] In order to maintain the acidity of the reforming catalyst and regulate the "water-chlorine" balance, dichloroethane, trichloroethane and carbon tetrachloride are injected, which in turn causes the reforming hydrogen to contain trace amounts of HCl. At present, the refinery requires that the hydrogen chloride content in the reforming hydrogen be less than 1 mg / l. If the chlorine content exceeds the standard, it will have a great impact on the downstream device, especially the hydrogenation device, and will produce serious ammonium chloride crystallization, corrode the device and equipment, and seriously endanger the long-period operation of the production device.

[0003] At present, the reforming device usually uses low-temperature chemical adsorption dechlorination agent, which is not renewable and is replaced about every three to six months. The replacement frequency is related to the operating conditions, but this replacement frequency still cannot avoid the phenomenon of ammonium chloride crystallization in the downstream device. The existing chemical adsorption dechlorination agent is easy to harden and the hydrogen gas flow is short.

[0004] CN100344363C discloses an adsorbent for adsorbing hydrogen chloride impurities in gaseous or liquid hydrocarbons. The adsorbent comprises 25-80 wt% of alumina, 1-60 wt% of a filler selected from white clay or bentonite, and 5-65 wt% of a metal oxide selected from zinc oxide, magnesium oxide or sodium oxide. The adsorbent can further contain 0.3-5.0 wt% of manganese oxide. CN106268832A discloses a dechlorination agent, which uses one or more of Na2CO3, CaCO3, CaO, MgO, CuO, ZnO and derivatives thereof as active components, NH4HCO3 as a porous auxiliary agent, at least one of Al2O3, diaspore, kaolin or white clay as a carrier and auxiliary agent, and part of modified Zn salt and Ca salt as a synergistic auxiliary agent. CN106334516A discloses a high-pressure-resistant dechlorination agent, which comprises an active component, i.e. a composite metal oxide selected from one or more of CaO, MgO, ZnO and CuO, and a carrier of pseudo-boehmite powder. From the above dechlorination agents, it can be seen that the chemical dechlorination agent is mainly used in the industry to remove hydrogen chloride in reforming hydrogen, and its dechlorination performance is questionable. The product after dechlorination will be solid waste, which is difficult to handle.

[0005] CN109499526A discloses a kind of removal inorganic chlorine and active carbon base dechlorination agent of organic chlorine in propylene stream and preparation thereof, comprising the following components: modified active carbon 50~70 parts, dechlorination agent containing Lewis acid center 5~20 parts, zeolite molecular sieve 0~10 parts, alkali metal or alkaline earth metal 1~10 parts, transition metal 5~15 parts, binder 0.5~2 parts and pore expander 1~5 parts;Mix powder first, then be obtained by extrusion molding, drying and calcination activation, the breakthrough chlorine capacity of the active carbon base dechlorination agent is ≥15%, saturated chlorine capacity is ≥18%, lateral pressure strength is ≥85N / cm, specific surface area is ≥600m 2 / g, pore volume is 0.45~0.65cm 3 / g, bulk weight is ≥0.50kg / L, abrasion is ≤3%.Among them, modified active carbon carrier is the active carbon treated by acid, alkali or strong oxidant, and the active carbon uses one of coal quality active carbon, coconut shell active carbon or wood active carbon.This dechlorination agent is used for reforming hydrogen dechlorination, and still belongs to traditional chemical adsorption dechlorination agent. SUMMARY

[0006] In view of the deficiencies in the prior art, the present application provides a kind of reforming hydrogen dechlorination agent and its preparation method and application in reforming hydrogen dechlorination process.The chloride content in reforming hydrogen can be reduced to below 0.5mg / L by using the dechlorination agent of the present application, which has a higher breakthrough chlorine capacity.

[0007] The present application provides a kind of preparation method of reforming hydrogen dechlorination agent, comprising:

[0008] (1) the petroleum coke is dried, then mixed with alkaline earth metal peroxide, pretreated;

[0009] (2) the mixture after pretreatment of step (1) is mixed with alkali, and high temperature treatment is carried out under inert atmosphere conditions, washed, dried;

[0010] (3) the dry material obtained in step (2) is oxidized and modified, washed, dried, to obtain the dechlorination agent.

[0011] Further, in step (1), the petroleum coke is the petroleum coke produced by delayed coking device.

[0012] Further, in step (1), the petroleum coke is dried under the following conditions: drying temperature is 60~150℃, preferably 80~120℃, drying time is 2~8h, preferably 3~5h.

[0013] Further, in step (1), the alkaline earth metal is preferably one and several of magnesium, calcium and strontium.

[0014] Further, in step (1), the mass ratio of the alkaline earth metal peroxide to the dried petroleum coke is 0.01:1 to 0.5:1, preferably 0.03:1 to 0.1:1.

[0015] Further, in step (1), the pretreatment conditions are as follows: the temperature is 200 to 600°C, preferably 300 to 500°C, and the time is 2 to 8 h, preferably 3 to 5 h.

[0016] Further, in step (2), the base is one or both of potassium hydroxide and sodium hydroxide.

[0017] Further, in step (2), the mass ratio of the base to the pretreated mixture of step (1) is 0.1:1 to 5:1, preferably 0.5:1 to 3:1.

[0018] Further, in step (2), the inert atmosphere is at least one of nitrogen, helium, and argon.

[0019] Further, in step (2), the high-temperature treatment conditions are as follows: the temperature is 600 to 1000°C, preferably 700 to 900°C, and the treatment time is 30 to 180 min, preferably 60 to 120 min.

[0020] Further, in step (3), after the high-temperature treatment, cooling is performed in the presence of nitrogen, and after the cooling, the sample is ground into a powder and washed. The washing can be performed using an acidic solution having a pH of not more than 7, the acid source in the acid solution being one or more of hydrochloric acid, sulfuric acid, nitric acid, and acetic acid, preferably acetic acid, and the washing is performed until the filtrate is neutral.

[0021] Further, in step (3), the drying temperature is 60 to 150°C, preferably 80 to 120°C, and the drying time is 2 to 10 h, preferably 4 to 8 h.

[0022] Further, in step (3), the oxidizing modifier used for the modification is at least one of nitric acid and hydrogen peroxide, preferably nitric acid. The concentration of the nitric acid is 0.01 to 15 mol / L, preferably 1 to 10 mol / L. The concentration of the hydrogen peroxide is 0.01 to 9 mol / L, preferably 3 to 8 mol / L. Specifically, a supersaturated impregnation method can be used, the modification time is 0.5 to 72 h, preferably 12 to 48 h, and the mass ratio of the modifier to the dried product of step (2) is 200:1 to 0.1:1, preferably 100:1 to 20:1.

[0023] Further, in step (3), the washing is performed using deionized water until the neutral.

[0024] Further, in step (3), the drying temperature is 60-150℃, preferably 80-120℃, and the drying time is 2-10h, preferably 4-8h.

[0025] The application also provides a reforming hydrogen dechlorination agent prepared by the above method.

[0026] Further, the specific surface area of the reforming hydrogen dechlorination agent is 800-3900m 2 / g, the pore volume is 0.4-2.0cm 3 / g, the most probable pore diameter is 0.6-0.8nm, and the micropore volume accounts for 70%-95% of the total pore volume.

[0027] Further, in the reforming hydrogen dechlorination agent, the loading amount of the alkaline earth metal is 1-15wt.%.

[0028] The application also provides a reforming hydrogen dechlorination method, wherein the dechlorination agent is prepared by the above method.

[0029] Further, the reforming hydrogen dechlorination method comprises: contacting the reforming hydrogen with the above dechlorination agent to obtain purified reforming hydrogen.

[0030] Further, the content of hydrogen chloride in the reforming hydrogen is 0.5-100mg / L, preferably 0.5-30mg / L.

[0031] Further, the reforming hydrogen dechlorination method adopts a fixed bed reactor. The fixed bed dechlorination conditions are as follows: pressure 0.1-5MPa, preferably 1.5-3MPa; temperature 0-80℃, preferably 3-12℃; and volume space velocity 50-5000h -1 , preferably 500-2000h -1 .

[0032] Further, when the content of hydrogen chloride at the outlet of the fixed bed reactor is greater than 0.5mg / L, this is the breakthrough point, which is recorded as the breakthrough chlorine capacity.

[0033] Compared with the prior art, the dechlorination agent has the following advantages:

[0034] 1. The preparation method of the reforming hydrogen dechlorination agent in the application, on the one hand, in-situ synthesis technology is used to introduce double dechlorination active centers, i.e. active metal core and oxygen-containing functional group core, into activated carbon with high specific surface area and taking petroleum coke as a carbon source, so as to construct a reforming hydrogen dechlorination agent mainly based on chemical adsorption and supplemented by physical adsorption. Since the active metal and the oxygen-containing functional group are mainly uniformly distributed in the activated carbon pore channel, hydrogen chloride mainly occurs in the adsorption sites in the pore channel, and less adsorption occurs on the outer surface of the adsorbent, thereby fundamentally changing the problems of easy hardening of the existing chemical adsorption dechlorination agent and short hydrogen flow path, and greatly improving the mass transfer problem. On the other hand, the surface properties of the petroleum coke are oxidized and modified in-situ through pretreatment, so that the interface properties of the oxidized and modified agent used later are more similar, the interface energy is reduced, and the amount of the oxidized and modified agent is correspondingly reduced.

[0035] 2. The method of the application uses petroleum coke as a carbon source and adopts a method combining alkali earth metal oxide pre-oxidation, alkali activation and oxidation modification, which is beneficial to constructing suitable gradient pore channels for the mass transfer and diffusion of hydrogen chloride in hydrogen, and is particularly suitable for reforming hydrogen dechlorination and has a high breakthrough chlorine capacity. DETAILED DESCRIPTION

[0036] The technical content and effects of the application will be further illustrated below in combination with examples, but the application is not limited by the examples.

[0037] In the application, the pore channel structure of the adsorption dechlorination agent used is measured by using an ASAP-2420M full-automatic specific surface area and pore analyzer of Micromeritics Company, USA.

[0038] In the application, a fixed bed adsorber is used to evaluate the adsorption dechlorination effect, and the hydrogen chloride content in hydrogen is measured by using a microcoulomb method.

[0039] Example 1

[0040] The preparation method of the reforming hydrogen dechlorination agent in the example includes:

[0041] (1) Petroleum coke is dried at 100℃ for 4h, and then mixed with calcium peroxide at a mass ratio of 0.1:1, pretreated, and the pretreatment conditions are as follows: the temperature is 450℃, and the time is 4h;

[0042] (2) The pretreated mixture in step (1) is mixed with potassium hydroxide at a mass ratio of 1:2, high-temperature treated under the condition of nitrogen (the temperature is 800℃, and the treatment time is 80min), washed with acetic acid until the pH value of the filtrate is neutral, and dried at 100℃ for 6h;

[0043] (3) The dry product obtained in step (2) is subjected to oxidative modification (supersaturated impregnation method, mass ratio of nitric acid to dry product of step (2) is 70:1, modification time is 24 h) using nitric acid with a concentration of 10 mol / L as the oxidative modifier, washed to neutral with deionized water, and dried at 100°C for 6 h to obtain the dechlorination agent A-1.

[0044] The specific surface area of the dechlorination agent A-1 for reforming hydrogen is 2100 m 2 / g, the pore volume is 1.25 cm 3 / g, the most probable pore diameter is 0.65 nm, and the micropore volume is 1.09 cm 3 / g.

[0045] Evaluation of the dechlorination agent A-1 for reforming hydrogen: A fixed bed reactor is used, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure is 2 MPa, temperature is 8°C, and volume space velocity is 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as Q C -1.

[0046] Example 2

[0047] The preparation method of the dechlorination agent for reforming hydrogen in this example comprises:

[0048] (1) Petroleum coke is dried at 100°C for 4 h, then mixed with strontium peroxide at a mass ratio of 0.05:1, and pretreated, the pretreatment conditions are as follows: temperature is 500°C, and time is 5 h;

[0049] (2) The pretreated mixture of step (1) is mixed with potassium hydroxide at a mass ratio of 1:3, and subjected to high-temperature treatment under the condition of nitrogen (temperature is 900°C, and treatment time is 120 min), washed with hydrochloric acid until the pH value of the filtrate is neutral, and dried at 100°C for 6 h;

[0050] (3) The dry product obtained in step (2) is subjected to oxidative modification (supersaturated impregnation method, mass ratio of nitric acid to dry product of step (2) is 100:1, modification time is 12 h) using nitric acid with a concentration of 8 mol / L as the oxidative modifier, washed to neutral with deionized water, and dried at 100°C for 6 h to obtain the dechlorination agent A-2.

[0051] The specific surface area of the dechlorination agent A-2 for reforming hydrogen is 3100 m 2 / g, the pore volume is 1.55 cm 3 / g, the most probable pore diameter is 0.68 nm, and the micropore volume is 1.41 cm 3 / g.

[0052] Evaluation of reforming hydrogen dechlorination agent A-2: using a fixed bed reactor, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure 2 MPa, temperature 8 ℃, volume space velocity 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as Q C -2.

[0053] Example 3

[0054] The preparation method of the reforming hydrogen dechlorination agent in this example includes:

[0055] (1) The petroleum coke is dried at 100 ℃ for 4 h, and then mixed with magnesium peroxide at a mass ratio of 0.03:1, and pretreated, and the pretreatment conditions are as follows: temperature 400 ℃, time 3 h;

[0056] (2) The pretreated mixture in step (1) is mixed with potassium hydroxide at a mass ratio of 1:1, and high temperature treatment is carried out under nitrogen condition (temperature 700 ℃, treatment time 60 min), and washed with acetic acid until the filtrate pH value is neutral, and dried at 100 ℃ for 6 h;

[0057] (3) The dried material obtained in step (2) is subjected to oxidative modification using hydrogen peroxide with a concentration of 8 mol / L as an oxidative modifier (supersaturated impregnation method, mass ratio of hydrogen peroxide to dried material is 100:1, modification time is 48 h), and washed with deionized water until neutral, and dried at 100 ℃ for 6 h to obtain the dechlorination agent A-3.

[0058] The specific surface area of the reforming hydrogen dechlorination agent A-3 is 1300 m 2 / g, the pore volume is 0.65 cm 3 / g, the most probable pore size is 0.60 nm, and the micropore volume is 0.59 cm 3 / g.

[0059] Evaluation of reforming hydrogen dechlorination agent A-3: using a fixed bed reactor, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure 2 MPa, temperature 8 ℃, volume space velocity 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as Q C -3.

[0060] Example 4

[0061] The preparation method of the reforming hydrogen dechlorination agent in this example includes:

[0062] (1) Petroleum coke was dried at 100°C for 4h, and then mixed with calcium peroxide and magnesium peroxide at a mass ratio of 0.1:1, wherein the mass ratio of calcium peroxide to magnesium peroxide was 1:1, and the mixture was pretreated at a temperature of 500°C for 4h;

[0063] (2) The pretreated mixture of step (1) was mixed with potassium hydroxide at a mass ratio of 1:1, and high-temperature treatment was performed under nitrogen (temperature 900°C, treatment time 120min), and the mixture was washed with acetic acid until the filtrate was neutral, and then dried at 100°C for 6h;

[0064] (3) The dried mixture of step (2) was oxidatively modified using nitric acid with a concentration of 10 mol / L as an oxidative modifier (over-saturation impregnation method, mass ratio of nitric acid to the dried mixture of step (2) was 30:1, modification time was 24h), and then washed with deionized water until neutral, and dried at 100°C for 6h to obtain the dechlorination agent A-4.

[0065] The specific surface area of the reforming hydrogen dechlorination agent A-4 was 1091 m 2 / g, the pore volume was 0.59 cm 3 / g, the most probable pore diameter was 0.61 nm, and the micropore volume was 0.42 cm 3 / g.

[0066] Evaluation of the reforming hydrogen dechlorination agent A-4: a fixed bed reactor was used, the hydrogen chloride content in the reforming hydrogen was 30mg / L, and the dechlorination conditions were as follows: operating pressure 2MPa, temperature 8°C, and volume space velocity 2000h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor was greater than 0.5mg / L, the breakthrough chlorine capacity was recorded as Q C -4.

[0067] Example 5

[0068] The preparation method of the reforming hydrogen dechlorination agent in this example comprises:

[0069] (1) Petroleum coke was dried at 100°C for 4h, and then mixed with calcium peroxide and magnesium peroxide at a mass ratio of 0.1:1, wherein the mass ratio of calcium peroxide to magnesium peroxide was 1:1, and the mixture was pretreated at a temperature of 500°C for 4h;

[0070] (2) The pretreated mixture of step (1) was mixed with potassium hydroxide at a mass ratio of 1:3, and high-temperature treatment was performed under nitrogen (temperature 900°C, treatment time 120min), and the mixture was washed with acetic acid until the filtrate was neutral, and then dried at 100°C for 6h;

[0071] (3) The dry product obtained in step (2) is subjected to oxidative modification (over-saturation impregnation method, mass ratio of nitric acid to dry product of step (2) is 90:1, modification time is 36 h) using nitric acid with a concentration of 9 mol / L as the oxidative modifier, washed to neutral with deionized water, and dried at 100°C for 6 h to obtain the dechlorination agent A-5.

[0072] The specific surface area of the dechlorination agent A-5 for reforming hydrogen is 3317 m 2 / g, the pore volume is 1.71 cm 3 / g, the most probable pore diameter is 0.71 nm, and the micropore volume is 1.59 cm 3 / g.

[0073] Evaluation of the dechlorination agent A-5 for reforming hydrogen: A fixed bed reactor is used, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure is 2 MPa, temperature is 8°C, and volume space velocity is 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as Q C -5.

[0074] Example 6

[0075] The preparation method of the dechlorination agent for reforming hydrogen in this example comprises:

[0076] (1) Petroleum coke is dried at 100°C for 4 h, then mixed with calcium peroxide at a mass ratio of 0.1:1, and subjected to pretreatment, the pretreatment conditions are as follows: temperature is 450°C, and time is 4 h;

[0077] (2) The pretreated mixture of step (1) is mixed with potassium hydroxide at a mass ratio of 1:2, subjected to high-temperature treatment under the condition of nitrogen (temperature is 800°C, and treatment time is 80 min), washed with acetic acid until the pH value of the filtrate is neutral, and dried at 100°C for 6 h;

[0078] (3) The dry product obtained in step (2) is subjected to oxidative modification (over-saturation impregnation method, mass ratio of nitric acid to dry product of step (2) is 70:1, modification time is 24 h) using nitric acid with a concentration of 10 mol / L as the oxidative modifier, washed to neutral with deionized water, and dried at 100°C for 6 h to obtain the dechlorination agent A-6.

[0079] The specific surface area of the dechlorination agent A-6 for reforming hydrogen is 2100 m 2 / g, the pore volume is 1.25 cm 3 / g, the most probable pore diameter is 0.65 nm, and the micropore volume is 1.09 cm 3 / g.

[0080] Evaluation of the reforming hydrogen dechlorination agent A-6: using a fixed bed reactor, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure 1.5 MPa, temperature 8 ℃, volume space velocity 500 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as Q C -6.

[0081] Comparative Example 1

[0082] The preparation method of the reforming hydrogen dechlorination agent in this example includes:

[0083] (1) The anthracite is dried at 100 ℃ for 4 h, and mixed with calcium peroxide and strontium peroxide at a mass ratio of 0.1:1, wherein the mass ratio of calcium peroxide to strontium peroxide is 1:1, and the mixture is pretreated at a temperature of 500 ℃ for 5 h;

[0084] (2) The pretreated mixture in step (1) is mixed with potassium hydroxide at a mass ratio of 1:3, and high-temperature treatment is carried out under nitrogen (temperature 900 ℃, treatment time 120 min), and washed with acetic acid until the filtrate is neutral, and dried at 100 ℃ for 6 h;

[0085] (3) The dried material obtained in step (2) is subjected to oxidative modification using concentrated nitric acid as an oxidative modifier (supersaturated impregnation method, mass ratio of nitric acid to dried material in step (2) is 90:1, modification time is 36 h), and washed with deionized water until neutral, and dried at 100 ℃ for 6 h to obtain the dechlorination agent B-1.

[0086] The specific surface area of the reforming hydrogen dechlorination agent B-1 is 775 m 2 / g, the pore volume is 0.39 cm 3 / g, the most probable pore size is 0.51 nm, and the micropore volume is 0.35 cm 3 / g.

[0087] Evaluation of the reforming hydrogen dechlorination agent B-1: using a fixed bed reactor, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure 2 MPa, temperature 8 ℃, volume space velocity 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as D C -1.

[0088] Comparative Example 2

[0089] The preparation method of the reforming hydrogen dechlorination agent in this example includes:

[0090] (1) The petroleum coke is dried at 100°C for 4h, then mixed with potassium hydroxide and silver oxide at a mass ratio of 1:3:0.1, and subjected to high-temperature treatment under nitrogen (temperature is 900°C, and treatment time is 60 min), washed with acetic acid until the filtrate is neutral, and dried at 100°C for 6h;

[0091] (2) The sample is cooled under nitrogen protection, ground into powder after cooling, washed with a 10wt% acetic acid solution, washed with deionized water until the filtrate is neutral, and then dried at 120°C for 6h to obtain an activated carbon intermediate product.

[0092] (3) The prepared activated carbon intermediate product is subjected to oxidative modification at room temperature using a gas with a volume content of 5% oxygen (nitrogen is used as the carrier gas), the modification time is 6h, the volume space velocity is 100h -1 , and then purged with nitrogen at a space velocity of 100h -1 for 6h to prepare the adsorbent. The specific surface area of the prepared adsorbent is 2900m 2 / g, the pore volume is 1.09cm3 / g, and the most probable pore diameter is 0.6-0.7nm, and the dechlorination agent B-2 is obtained.

[0093] Evaluation of the reforming hydrogen dechlorination agent B-2: A fixed bed reactor is used, the hydrogen chloride content in the reforming hydrogen is 30mg / L, the dechlorination conditions are: operating pressure is 2MPa, temperature is 8°C, and volume space velocity is 2000h -1 , and when the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5mg / L, the breakthrough chlorine capacity is recorded as D C -2.

[0094] Comparative Example 3

[0095] The preparation method of the reforming hydrogen dechlorination agent in this example comprises:

[0096] (1) The petroleum coke is dried at 100°C for 4h, then mixed with potassium hydroxide at a mass ratio of 1:3, and subjected to high-temperature treatment under nitrogen (temperature is 900°C, and treatment time is 60 min), washed with acetic acid until the filtrate is neutral, and dried at 100°C for 6h.

[0097] (2) The activated carbon obtained in step (1) is dried at 100°C for 4h, then mixed with calcium peroxide and strontium peroxide at a mass ratio of 0.1:1, and the mass ratio of calcium peroxide to strontium peroxide is 1:1, and subjected to pretreatment, and the pretreatment conditions are as follows: temperature is 500°C, time is 5h, washed with deionized water until neutral, and dried at 100°C for 6h to obtain the dechlorination agent B-3.

[0098] The specific surface area of the reforming hydrogen dechlorination agent B-3 is 2310m 2 / g, the pore volume is 0.81 cm 3 / g, the most probable pore size is 1.1 nm.

[0099] Evaluation of the reforming hydrogen dechlorination agent B-3: using a fixed bed reactor, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure 2 MPa, temperature 8 ℃, volume space velocity 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as D C -3.

[0100] Comparative Example 4

[0101] The preparation method of the reforming hydrogen dechlorination agent in this example includes:

[0102] (1) The petroleum coke is dried at 100 ℃ for 4 h, the petroleum coke, potassium hydroxide and magnesium hydroxide are mixed in a mass ratio of 1:2:0.1, and high temperature treatment is carried out under the condition of nitrogen (temperature is 800 ℃, and treatment time is 80 min). After washing with acetic acid until the pH value of the filtrate is neutral, drying is carried out at 100 ℃ for 6 h;

[0103] (2) The dried material obtained in step (2) is subjected to oxidation modification using concentrated nitric acid as an oxidation modifier (supersaturated impregnation method, the mass ratio of nitric acid to the dried material in step (2) is 70:1, and the modification time is 24 h). After washing with deionized water until neutral, drying is carried out at 100 ℃ for 6 h, and the dechlorination agent B-4 is obtained.

[0104] The specific surface area of the reforming hydrogen dechlorination agent B-4 is 1819 m 2 / g, the pore volume is 0.91 cm 3 / g, the most probable pore size is 0.51 nm, and the micropore pore volume is 0.71 cm 3 / g.

[0105] Evaluation of the reforming hydrogen dechlorination agent B-4: using a fixed bed reactor, the hydrogen chloride content in the reforming hydrogen is 30 mg / L, the dechlorination conditions are: operating pressure 2 MPa, temperature 8 ℃, volume space velocity 2000 h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5 mg / L, the breakthrough chlorine capacity is recorded as D C -4.

[0106] Comparative Example 5

[0107] The preparation method of the reforming hydrogen dechlorination agent in this example includes:

[0108] (1) The petroleum coke is dried at 100 ℃ for 4 h, the reaction temperature is 70 ℃, the pressure is 2 atm, ozone is used, and the volume space velocity is 1000 h -1, the oxidation treatment time is 8h. Then the oxidized product is washed with water until neutral, and dried at 120℃ for 6h.

[0109] (2) The pretreated oxidized petroleum coke in step (1) is mixed with potassium hydroxide and magnesium hydroxide at a mass ratio of 1:2:0.1, and high-temperature treatment is carried out under nitrogen condition (temperature is 800℃, treatment time is 80min), washed with acetic acid until the pH value of the filtrate is neutral, and dried at 100℃ for 6h;

[0110] (3) The dried product obtained in step (2) is subjected to oxidation modification (supersaturated immersion method, the mass ratio of nitric acid to the dried product in step (2) is 70:1, and the modification time is 24h) using nitric acid with a concentration of 10mol / L as the oxidation modifier, washed with deionized water until neutral, and dried at 100℃ for 6h to obtain the dechlorination agent B-5.

[0111] The specific surface area of the reforming hydrogen dechlorination agent B-5 is 1916m 2 / g, the pore volume is 1.01cm 3 / g, the most probable pore diameter is 0.59nm, and the micropore volume is 0.85cm 3 / g.

[0112] Evaluation of the reforming hydrogen dechlorination agent B-5: a fixed bed reactor is used, the hydrogen chloride content in the reforming hydrogen is 30mg / L, and the dechlorination conditions are as follows: operating pressure is 2MPa, temperature is 8℃, and volume space velocity is 2000h -1 When the hydrogen chloride content at the outlet of the fixed bed reactor is greater than 0.5mg / L, the breakthrough chlorine capacity is recorded as D C -5.

[0113] Table 1 shows the dechlorination effects of the dechlorination agents obtained in each example

[0114]

[0115]

[0116] The embodiments described in the present application are only detailed descriptions of the technical solutions of the present application, but the present application is not limited to the above-mentioned embodiments, that is, the present application can be implemented without relying on the steps described in the above-mentioned embodiments. In summary, any improvement made by a person skilled in the art to the present application, as long as it does not deviate from the content of the technical solutions of the present application, any simple modification, equivalent change and modification made to the above-mentioned embodiments according to the technical essence of the present application, all belong to the protection scope and disclosure scope of the present application.

Claims

1. A process for the preparation of a reforming hydrogen dechlorination agent wherein, The specific surface area of the reforming hydrogen dechlorination agent is 800-3900 m 2 / g, and the pore volume is 0.4-2.0 cm 3 / g, the most probable pore diameter is 0.6-0.7 nm, and the micropore volume accounts for 70-95% of the total pore volume; and the preparation method comprises: (1) drying petroleum coke, and then mixing with alkaline earth metal peroxide, and pre-treating; (2) mixing the pre-treated mixture in step (1) with alkali, and high-temperature treating under inert atmosphere, and washing, and drying; (3) oxidizing and modifying the dried product in step (2), and washing, and drying, to obtain the dechlorination agent; In step (1), the alkaline earth metal is one or several of magnesium, calcium and strontium; the mass ratio of the alkaline earth metal peroxide to the dried petroleum coke is 0.01:1-0.5:1; In step (1), the pre-treating conditions are as follows: the temperature is 200-600℃, and the time is 2-8h; In step (2), the alkali is one or both of potassium hydroxide and sodium hydroxide; the mass ratio of the alkali to the pre-treated mixture in step (1) is 0.1:1-5:1; In step (2), the high-temperature treating conditions are as follows: the temperature is 600-1000℃, and the treating time is 30-180min; In step (3), the oxidizing modifier is at least one of nitric acid and hydrogen peroxide; the mass ratio of the oxidizing modifier to the dried product in step (2) is 200:1-0.1:

1.

2. The method of claim 1, wherein, In step (1), the drying conditions of the petroleum coke are as follows: the drying temperature is 60-150℃, and the drying time is 2-8h; and / or, in step (3), the drying temperature is 60-150℃, and the drying time is 2-10h.

3. The method of claim 2, wherein, In step (1), the drying conditions of the petroleum coke are as follows: the drying temperature is 80-120℃, and the drying time is 3-5h; and / or, in step (3), the drying temperature is 80-120℃, and the drying time is 4-8h.

4. The method of claim 1, wherein, In step (1), the mass ratio of the alkaline earth metal peroxide to the dried petroleum coke is 0.03:1-0.1:

1.

5. The method of claim 1, wherein, In step (1), the pre-treating conditions are as follows: the temperature is 300-500℃, and the time is 3-5h.

6. The method of claim 1, wherein, In step (2), the mass ratio of the alkali to the pre-treated mixture in step (1) is 0.5:1-3:

1.

7. The method of claim 1, wherein, In step (2), the high-temperature treating conditions are as follows: the temperature is 700-900℃, and the treating time is 60-120min.

8. The method of claim 1, wherein, In step (3), the washing uses an acidic solution with a pH value not greater than 7; the acid in the acidic solution is one or several of hydrochloric acid, sulfuric acid, nitric acid and acetic acid; and the washing is performed until the pH value of the filtrate is neutral; and / or, in step (3), the drying temperature is 60-150℃, and the drying time is 2-10h.

9. The method of claim 8, wherein, In step (3), the acid in the acidic solution is acetic acid; and / or, in step (3), the drying temperature is 80-120℃, and the drying time is 4-8h.

10. The method of claim 1, wherein, In step (3), the concentration of the nitric acid is 0.01-15mol / L, and the concentration of the hydrogen peroxide is 0.01-9mol / L.

11. The method of claim 10, wherein, In step (3), the concentration of the nitric acid is 1-10mol / L, and the concentration of the hydrogen peroxide is 3-8mol / L.

12. The method of claim 1, wherein, In step (3), the oxidizing and modifying uses a supersaturated impregnation method, and the modifying time is 0.5-72h.

13. The method of claim 1, wherein, In step (3), the mass ratio of the modifier to the dried material obtained in step (2) is 100:1 to 20:

1.

14. A reforming hydrogen chloride removal agent prepared by the method of any one of claims 1 to 13.

15. The reforming hydrogen dechlorination agent of claim 14, wherein In the reforming hydrogen chloride removal agent, the loading of the alkaline earth metal is 5 wt% to 20 wt%.

16. A method of dechlorination by reforming hydrogen, characterized by The reforming hydrogen chloride removal agent of any one of claims 14 to 15.

17. The method of claim 16, wherein, The content of hydrogen chloride in the reforming hydrogen is 0.5 to 100 mg / L.

18. The method of claim 17, wherein, The content of hydrogen chloride in the reforming hydrogen is 0.5 to 30 mg / L.

19. The method of claim 16, wherein, The reforming hydrogen dechlorination method adopts a fixed bed reactor, wherein the fixed bed dechlorination conditions are: the pressure is 0.1-5 MPa, the temperature is 0-80℃, the volume space velocity is 50-5000 h -1 .

20. The method of claim 19, wherein, The reforming hydrogen dechlorination method adopts a fixed bed reactor, wherein the fixed bed dechlorination conditions are: the pressure is 1.5-3 MPa, the temperature is 3-12 ℃, the volume space velocity is 500-2000 h -1 .

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