Macroporous liquid dechlorination agent, its preparation method and application

Abstract

The present application relates to a kind of macroporous volume liquid phase dechlorination agent and its preparation method and application, macroporous volume liquid phase dechlorination agent includes the following weight parts components: dechlorination active substance M modified silica gel micro powder 45~70 parts;Inorganic macroporous material 15~25 parts;Clay 15~25 parts;The dechlorination active substance M is selected from Ca, Mg, and / or Zn, Fe, Cu element one or several;By dechlorination active component highly dispersed in water glass, then with dilute sulfuric acid rapid reaction, preparation micron modified silica gel micro powder, then with inorganic macroporous material, clay is mixed into shape, preparation into high activity, macropore diameter, macroporous volume liquid phase dechlorination agent, because dechlorination active component in situ high dispersion, macropore diameter improves liquid phase diffusion, macroporous volume improves dechlorination capacity.Compared with prior art, the present application is suitable for the removal of inorganic chlorine or organic chlorine in oil product, especially the removal of hydrogen chloride or organic chlorine in reforming product oil, it has higher dechlorination efficiency and dechlorination precision in liquid phase dechlorination process.

Description

Technical Field

[0001] This invention relates to the field of liquid-phase dechlorination agent technology, specifically to a macroporous liquid-phase dechlorination agent, its preparation method, and its application. Background Technology

[0002] Continuous reforming is a major process technology for producing aromatics and high-octane gasoline components. During the reforming reaction, chlorine on the reforming catalyst is continuously lost, requiring the continuous injection of water and organochlorides to maintain water-chlorine balance during operation. Besides the chlorine retained by the reforming catalyst, the chlorine entering the reaction system dissolves in the reformate and reformate recycle hydrogen. Typically, the chlorine content in the reformate is 2–4 μg / L. When the reformate is used as feedstock for aromatics extraction, the sulfolane used for extraction generally has a water content of 1.0%. Simultaneously, a certain proportion of stripping water is required in the recovery tower operation. The presence of water causes trace amounts of chlorine in the reformate to exist as hydrogen chloride. With prolonged operation and repeated solvent circulation, the hydrogen chloride concentration in the system increases, leading to equipment corrosion. Furthermore, the presence of chlorine accelerates the deterioration of the aromatics extraction solvent sulfolane. The degraded sulfolane further combines with chlorine, accelerating equipment corrosion.

[0003] For chlorine contained in reformed oil and pentane oil, a special liquid-phase dechlorination agent is used for removal. Since the dechlorination reaction of reformed oil is a liquid-solid reaction, the mass transfer rate in the liquid phase system is currently low, and the chlorine capacity of the dechlorination agent is still low, with a breakthrough chlorine capacity generally between 10 and 12% by mass, resulting in a large amount of dechlorination agent used and frequent replacement.

[0004] The water produced after the dechlorination reaction of conventional dechlorination agents can cause dechlorination agents containing alkali metals or alkaline earth metals to clump or have their physical structure damaged, such as reduced strength or collapse, thus affecting their industrial use.

[0005] The diffusion resistance of HCl in the liquid phase is much greater than that of HCl molecules in the gas phase. Therefore, when preparing liquid dechlorinating agents, in addition to considering the active components, the specific surface area, pore size and pore volume of the dechlorinating agent should be the main considerations.

[0006] Currently, most dechlorination agents on the market suffer from drawbacks due to limitations in carrier performance, including poor pore structure distribution, weak acid resistance, small specific surface area, low content of active components, and narrow applicability. In the preparation process, the active components are typically added through impregnation or direct solid-to-gas mixing.

[0007] Existing technologies using silica gel carriers often employ the method of impregnating the carrier with water-soluble salts. While this method results in a relatively uniform distribution of the active components, it also leads to wastewater pollution and a significant decrease in the surface area and pore volume of the adsorbent. In contrast, solid mixing methods, due to limitations in mixing efficiency and mass transfer, typically result in an uneven distribution of the active components and low utilization efficiency of the carrier pores, thus affecting the adsorption effect. Summary of the Invention

[0008] The purpose of this invention is to provide a macroporous liquid-phase dechlorination agent, its preparation method and application, wherein the dechlorination agent has large pore size, large pore volume and large specific surface area.

[0009] The objective of this invention can be achieved through the following technical solution: a macroporous liquid-phase dechlorination agent, comprising the following components by weight:

[0010] 45-70 parts of dechlorination active substance M modified silica gel micro powder;

[0011] 15-25 parts of inorganic macroporous material;

[0012] 15-25 parts clay;

[0013] The dechlorination active substance M is selected from one or more of the elements Ca, Mg, and / or Zn, Fe, and Cu.

[0014] Preferably, in the dechlorination active substance M modified silica gel micro powder, the weight ratio of dechlorination active substance M (calculated as oxide) to silica gel micro powder (calculated as SiO2) is (10-20):(80-90).

[0015] Preferably, the dechlorination active substance M modified silica gel micropowder has a pore volume of 1.7–2.8 mL / g and a specific surface area of ​​300–360 m². 2 / g, average pore size 25-30nm, average particle size 1-2μm.

[0016] Preferably, the inorganic macroporous material is selected from one or more of diatomaceous earth, hydrotalcite, and boehmite.

[0017] Preferably, the dechlorination active substance M is selected from one or more of oxides, carbonates, or hydroxides.

[0018] More preferably, the dechlorination active substance M is selected from one or more of zinc oxide, copper oxide, iron oxide, zinc carbonate, copper carbonate, calcium carbonate, and iron hydroxide.

[0019] More preferably, the dechlorination active substance M is selected from one or more of zinc oxide, zinc carbonate, or calcium carbonate.

[0020] Preferably, the dechlorination active substance M is a nano-sized particle.

[0021] Preferably, the dechlorination active substance M is selected from industrial raw materials and ball-milled in a ball mill. The inner wall of the ball mill jar is preferably lined with polytetrafluoroethylene (PTFE). The diameter of the grinding balls in the ball mill can be 2-3 mm. The number of grinding balls can be reasonably selected according to the size of the ball mill jar. For a ball mill jar with a size of 50-150 mL, one grinding ball can usually be used. The material of the grinding ball can be agate, PTFE, etc., preferably agate.

[0022] More preferably, the ball milling conditions include: a ball rotation speed of 300-500 r / min, a ball milling jar temperature of 15-100℃, and a ball milling time of 0.1-100 h.

[0023] Preferably, the dechlorination active substance M is uniformly dispersed in situ with the silica gel micro powder.

[0024] Preferably, the preparation method of the dechlorination active substance M modified silica gel micro powder includes the following steps:

[0025] (1) Under stirring, the dechlorination active substance M is added to a diluted water glass solution to form a stable suspension, and then reacted rapidly with a diluted sulfuric acid solution at 10-25°C for 10s-1min to obtain a liquid.

[0026] (2) The above liquid is sprayed into an alcohol solution with a water content of 6-10 wt% by spray molding, aged for 10-30 min, filtered, and washed with deionized water to obtain a water-containing filter cake.

[0027] (3) The water-containing filter cake is flash-dried at 150-200℃ to obtain the dechlorination active material M modified silica gel micro powder.

[0028] More preferably, the stirring conditions in step (1) are high-speed stirring at 2000-2500 r / min.

[0029] More preferably, the concentration of the diluted water glass solution in step (1) is 6-8% (SiO2 wt%).

[0030] More preferably, the concentration of the diluted sulfuric acid solution in step (1) is 6-8% (H2SO4 wt%).

[0031] More preferably, the weight ratio of the diluted water glass solution to the diluted sulfuric acid solution in step (1) is 3 to 5:1.

[0032] More preferably, the alcohol in step (2) is selected from one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, tert-butanol, and n-pentanol.

[0033] More preferably, the water content of the filter cake in step (2) is 63-67 wt%.

[0034] More preferably, the water content of the filter cake in step (2) is 53% to 57 wt%.

[0035] More preferably, the spray forming is performed in an atomizer.

[0036] More preferably, the spraying conditions include: a temperature of 20–100°C and a rotation speed of 10,000–15,000 r / min.

[0037] More preferably, the flash drying conditions in step (3) include: an inlet temperature of 150-200°C and an outlet temperature of 100-120°C.

[0038] A method for preparing the above-mentioned macroporous liquid-phase dechlorination agent involves uniformly mixing dechlorination active substance M modified silica gel micro powder, inorganic macroporous material, clay and water, and molding them into a liquid-phase dechlorination agent.

[0039] A method for preparing the above-mentioned macroporous liquid-phase dechlorination agent involves uniformly mixing and molding dechlorination active substance M modified silica gel micro powder, inorganic macroporous material, clay and water in a weight ratio of (45-70):(15-25):(15-25):(5-15), drying at 60-200°C for 40 minutes to 10 hours, and then further activating at a temperature range of 300-600°C for 20-200 minutes to obtain the macroporous liquid-phase dechlorination agent.

[0040] This invention utilizes the rapid reaction of an active component introduced into a water glass solution of appropriate concentration with a dilute sulfuric acid solution to embed the active component into a silica gel framework. The active component includes nano-sized zinc oxide, calcium carbonate, zinc carbonate, etc. High-activity, large-pore-size, and large-volume modified silica gel micropowder is prepared using high-speed dispersion, spray molding, washing and filtration, and flash drying methods. The modified silica gel micropowder is then uniformly mixed with inorganic macroporous materials and clay to obtain a mixture. This mixture is kneaded, extruded, dried, and calcined at 360℃ to 600℃ to obtain a liquid-phase dechlorination adsorbent. This process ensures high dispersion and high loading of the dechlorination active component in the dechlorination agent, with controllable process steps, effectively reducing production costs and facilitating industrial production.

[0041] An application of the above-mentioned macroporous liquid phase dechlorination agent is to use the macroporous liquid phase dechlorination agent for dechlorination of liquid phase streams.

[0042] Preferably, the liquid stream is a hydrocarbon-containing stream.

[0043] Preferably, the liquid phase stream comprises light oil or product oil from a catalytic reforming process.

[0044] More preferably, the dechlorination process conditions include: a treatment temperature of room temperature to 100°C; and a liquid hourly space velocity of 0.5 to 10 h⁻¹. -1 The reaction pressure is atmospheric pressure to 2 MPa.

[0045] More preferably, the liquid hourly space velocity (LHSV) is 2–10 h⁻¹. -1 .

[0046] Preferably, the liquid phase stream is directly subjected to dechlorination treatment without dehydration.

[0047] Preferably, the macroporous liquid-phase dechlorinating agent is suitable for the removal of inorganic or organic chlorine from oil products.

[0048] More preferably, the macroporous liquid-phase dechlorinating agent is suitable for removing hydrogen chloride or organochlorine from reformed oil.

[0049] Compared with the prior art, the present invention has the following beneficial effects:

[0050] 1. This invention provides a liquid-phase dechlorination agent and its preparation method. The prepared liquid-phase dechlorination agent has a uniform distribution of active centers and has large pore size, large pore volume and large specific surface area.

[0051] 2. The dechlorination agent of this invention has a large pore size and large chlorine capacity, which can meet the requirements of high air velocity and high precision dechlorination, and significantly reduce operating costs.

[0052] 3. The method of this invention has a simple preparation process, low preparation cost, and stable structure under acidic operating conditions. The neutral nature of silica eliminates oligomerization reactions during dechlorination. By reducing diffusion limitations through large pore size and volume, the dynamic desorption capacity of the dechlorinating agent in gaseous or liquid hydrocarbon streams is significantly improved, meeting the requirements for liquid-phase dechlorination at high space velocities.

[0053] 4. The dechlorination agent of this invention has a high loading of active components, uniform distribution, and high utilization rate.

[0054] 5. The dechlorination agent of this invention has strong water resistance, good water and oil resistance, excellent structural stability before and after the dechlorination reaction, stable performance, and does not cause problems such as caking or physical structure collapse during use.

[0055] 6. This invention can ensure high dispersion and high loading of dechlorination active components in dechlorination agents, controllable process steps, effectively reduce production costs, and is easy to realize industrial production. Detailed Implementation

[0056] The embodiments of the present invention will be described in detail below. The following embodiments are implemented based on the technical solution of the present invention, and detailed implementation methods and specific operation processes are given. However, the protection scope of the present invention is not limited to the following embodiments.

[0057] A method for preparing a macroporous liquid-phase dechlorination agent includes the following steps:

[0058] The first step involves adding the dechlorination active substance M to a diluted water glass solution under high-speed stirring to form a stable suspension, and then reacting it rapidly with a diluted sulfuric acid solution at 10–25°C for 10 seconds to 1 minute.

[0059] The second step involves spraying the above-mentioned liquid mixture into an alcohol solution with a water content of 6–10 wt% using a spray molding method, aging it for 10–30 minutes, filtering it, and washing it with deionized water to obtain a filter cake (containing 53 wt% to 57 wt% water).

[0060] The third step involves flash drying the water-containing filter cake at 150–200°C to obtain modified silica gel powder of 1–2 micrometers.

[0061] The fourth step involves uniformly mixing micron-sized modified silica powder, inorganic macroporous materials, clay, and water in a weight ratio of (45–70):(15–25):(15–25):(5–15) and molding the mixture. The mixture is then dried at 60–200°C for 40 minutes to 10 hours, and further activated at 300–600°C for 20–200 minutes to obtain the adsorbent.

[0062] The following detailed description is based on specific embodiments.

[0063] Example 1

[0064] According to the ZnO:SiO2 weight ratio of 1:9, nano zinc oxide was added to a 6wt% (SiO2 content) water glass solution under high-speed stirring at 2000 rpm and dispersed for 30 min to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added according to the water glass solution: dilute sulfuric acid solution weight ratio of 3:1, and the mixture was quickly mixed for 10 s. The mixture was then rapidly spray-molded, received with a 6% water content ethanol solution, stirred for 30 min, filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micron modified silica powder W1. Silica powder W1:diatomaceous earth:clay:water were mixed and kneaded in a weight ratio of 54:18:18:10, extruded into strips, and then dried at 120℃ for 2 h and calcined at 300℃ for 3 h to obtain the dechlorination agent S1.

[0065] Example 2

[0066] According to the ZnO:SiO2 weight ratio of 1.5:8.5, nano zinc carbonate was added to an 8wt% (SiO2 content) water glass solution under high-speed stirring at 2200 rpm and dispersed for 30 min to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added according to the water glass solution:dilute sulfuric acid solution weight ratio of 4:1, and the mixture was quickly mixed for 30 s. The mixture was then rapidly spray-molded, received with a 6% water content ethanol solution, stirred for 30 min, filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micron modified silica gel powder W2. The silica gel powder W2, pseudoboehmite, clay, and water were mixed and kneaded in a weight ratio of 54:18:18:10, extruded into strips, and then dried at 120℃ for 2 h and calcined at 450℃ for 3 h to obtain the dechlorination agent S2.

[0067] Example 3

[0068] According to the weight ratio of ZnO:CaO:SiO2 1:0.5:8.5, nano zinc oxide and nano calcium carbonate were added to a 7wt% (SiO2 content) water glass solution under high-speed stirring at 2000 rpm and dispersed for 30 min to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added according to the weight ratio of water glass solution:dilute sulfuric acid solution 5:1, and the mixture was quickly mixed for 20 s. The mixture was then rapidly spray-molded, received with a 6% water content ethanol solution, stirred for 30 min, filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micron modified silica gel powder W3. Silica gel powder W3:diatomaceous earth:clay:water were mixed and kneaded in a weight ratio of 54:18:18:10, extruded into strips, and then dried at 120℃ for 2 h and calcined at 400℃ for 3 h to obtain the dechlorination agent S3.

[0069] Example 4

[0070] According to the CuO:SiO2 weight ratio of 1:9, nano-copper oxide was added to a 6wt% (SiO2 content) water glass solution under high-speed stirring at 2500 rpm and dispersed for 30 min to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added according to the water glass solution:dilute sulfuric acid solution weight ratio of 4:1, and the mixture was quickly mixed for 40 s. The mixture was then rapidly spray-molded, received with a 6% water content ethanol solution, stirred for 30 min, filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micron modified silica gel powder W4. Silica gel powder W4:hydrotalcite:clay:water were mixed in a weight ratio of 51:17:17:15 to obtain a dechlorination agent precursor. The dechlorination agent precursor and sodium cellulose powder were mixed evenly according to a mass ratio of 1:0.04, extruded into strips, and then dried at 120℃ for 2 h and calcined at 500℃ for 3 h to obtain the dechlorination agent S4.

[0071] Example 5

[0072] First, industrial-grade zinc oxide was ball-milled to nanoscale. The milled zinc oxide was then added to a 6 wt% (SiO2 content) water glass solution under high-speed stirring at 2000 rpm for 30 minutes to obtain a stable suspension. Then, a 7% dilute sulfuric acid solution was added at a water glass solution: dilute sulfuric acid solution weight ratio of 4:1, and the mixture was rapidly mixed for 60 seconds. The mixture was then quickly spray-molded, received with a 6% water content ethanol solution, stirred for 30 minutes, filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micrometer modified silica gel powder W5. Silica gel powder W5, diatomaceous earth, clay, and water were mixed in a weight ratio of 51:17:17:15, extruded into strips, and then dried at 120℃ for 2 hours and calcined at 300℃ for 3 hours to obtain the dechlorinating agent S5.

[0073] Example 6

[0074] According to the weight ratio of ZnO:Fe2O3:CaO:SiO2 of 0.5:0.5:1:8, nano-zinc oxide, nano-iron oxide, and nano-calcium carbonate were separately added to a 6wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2000 rpm to obtain a stable suspension. Then, a 6% dilute sulfuric acid solution was added at a weight ratio of water glass solution to dilute sulfuric acid solution of 4:1, and the mixture was quickly mixed for 10 s. The mixture was then rapidly spray-dried and collected with a 6% water content ethanol solution. After collection, stir for 30 minutes, filter, wash with deionized water, and flash dry the filter cake to obtain 1-2 micron modified silica powder W6. Mix silica powder W6, diatomaceous earth, clay, and water in a weight ratio of 45:22.5:22.5:10 to obtain a dechlorination agent precursor. Mix the dechlorination agent precursor with sodium cellulose powder at a mass ratio of 1:0.04, extrude into strips, and then dry at 120℃ for 2 hours and calcine at 500℃ for 3 hours to obtain the dechlorination agent S6.

[0075] Example 7

[0076] According to the weight ratio of ZnO:Fe2O3:CaO:SiO2 of 1:0.5:0.5:8, nano-zinc oxide, nano-iron oxide, and nano-calcium carbonate were separately added to a 6wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2000 rpm to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added at a weight ratio of water glass solution to dilute sulfuric acid solution of 4:1, and the mixture was quickly mixed for 30 s. The mixture was then rapidly spray-dried and dissolved in 6% water-containing ethanol. After receiving the liquid, stir for 30 minutes, filter, wash with deionized water, and flash-dry the filter cake to obtain 1-2 micron modified silica powder W7. Mix silica powder W7, diatomaceous earth, clay, and water in a weight ratio of 54:18:18:10 to obtain a dechlorination agent precursor. Mix the dechlorination agent precursor with sodium cellulose powder at a mass ratio of 1:0.04, extrude into strips, and then dry at 120℃ for 2 hours and calcine at 500℃ for 3 hours to obtain the dechlorination agent S7.

[0077] Example 8

[0078] According to the weight ratio of ZnO:Fe2O3:CaO:SiO2 of 0.5:1:0.5:8, nano-zinc oxide, nano-iron oxide, and nano-calcium carbonate were separately added to a 6wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2000 rpm to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added at a weight ratio of water glass solution to dilute sulfuric acid solution of 4:1, and the mixture was rapidly mixed for 40 s. The mixture was then quickly spray-dried and collected with a 6% water content ethanol solution. After collection, stir for 30 minutes, filter, wash with deionized water, and flash dry the filter cake to obtain 1-2 micron modified silica powder W8. Mix silica powder W8, diatomaceous earth, clay, and water in a weight ratio of 63:13.5:13.5:10 to obtain a dechlorination agent precursor. Mix the dechlorination agent precursor with sodium cellulose powder at a mass ratio of 1:0.04, extrude into strips, and then dry at 120℃ for 2 hours and calcine at 500℃ for 3 hours to obtain the dechlorination agent S8.

[0079] Example 9

[0080] Nano-copper carbonate was added to a 6wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2500 rpm at a weight ratio of CuCO3:SiO2 of 1:9 to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added at a weight ratio of water glass solution:dilute sulfuric acid solution of 4:1 and rapidly mixed for 40 s. The mixture was then quickly spray-molded and received with a 6% water content ethanol solution. After stirring for 30 min, the mixture was filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micron modified silica gel powder W9. Silica gel powder W9, hydrotalcite, clay, and water were mixed in a weight ratio of 54:18:18:10 to obtain a dechlorination agent precursor. The dechlorination agent precursor was mixed with sodium cellulose powder at a mass ratio of 1:0.04 and extruded into strips. The strips were then dried at 120℃ for 2 h and calcined at 500℃ for 3 h to obtain the dechlorination agent S9.

[0081] Example 10

[0082] Nano-ferric hydroxide was added to a 6wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2500 rpm with a weight ratio of Fe(OH)3:SiO2 of 1:9 to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added at a weight ratio of water glass solution:dilute sulfuric acid solution of 4:1 and rapidly mixed for 40 s. The mixture was then quickly spray-molded and received with a 6% water content ethanol solution. After stirring for 30 min, the mixture was filtered, washed with deionized water, and the filter cake was flash-dried to obtain 1-2 micron modified silica gel powder W10. Silica gel powder W10, hydrotalcite, clay, and water were mixed in a weight ratio of 54:18:18:10 to obtain a dechlorination agent precursor. The dechlorination agent precursor was mixed with sodium cellulose powder at a mass ratio of 1:0.04 and extruded into strips. The strips were then dried at 120℃ for 2 h and calcined at 500℃ for 3 h to obtain the dechlorination agent S10.

[0083] Comparative Example 1

[0084] Industrial-grade zinc oxide was added to a 6 wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2000 rpm at a weight ratio of ZnO:SiO2 of 1.5:8.5 to obtain a stable suspension. Then, 8% dilute sulfuric acid solution was added at a weight ratio of water glass solution:dilute sulfuric acid solution of 4:1 and rapidly mixed for 30 s. The mixture was then quickly spray-molded and received with a 6% water content ethanol solution. After stirring for 30 min, the mixture was filtered, washed with deionized water, and the filter cake was flash-dried to obtain modified silica gel micropowder DW1. Silica gel micropowder DW1, diatomaceous earth, clay, and water were mixed in a weight ratio of 54:18:18:10 to obtain a dechlorination agent precursor. The dechlorination agent precursor was mixed with sodium cellulose powder at a mass ratio of 1:0.04 and then extruded into strips. The strips were then dried at 120℃ for 2 h and calcined at 500℃ for 3 h to obtain the dechlorination agent D1.

[0085] Comparative Example 2

[0086] Nano-sized zinc oxide was added to a 15wt% (SiO2 content) water glass solution and dispersed for 30 min under high-speed stirring at 2000 rpm at a weight ratio of ZnO:SiO2 of 1.5:8.5 to obtain a stable suspension. Then, 10% dilute sulfuric acid solution was added at a weight ratio of water glass solution:dilute sulfuric acid solution of 4:1 and the mixture was reacted for 30 min to directly obtain a gel. The gel was washed with deionized water and the filter cake was flash-dried to obtain modified silica gel micropowder DW2. Silica gel micropowder DW2, diatomaceous earth, clay, and water were mixed in a weight ratio of 54:18:18:10 to obtain a dechlorination agent precursor. The dechlorination agent precursor and sodium cellulose powder were mixed evenly at a mass ratio of 1:0.04, extruded into strips, and then dried at 120℃ for 2 h and calcined at 500℃ for 3 h to obtain the dechlorination agent D2.

[0087] Comparative Example 3

[0088] Nano-sized zinc oxide was added to a 15wt% (SiO2 content) water glass solution and dispersed for 30 min under mechanical stirring at 200 rpm, according to a ZnO:SiO2 weight ratio of 1.5:8.5, to obtain a stable suspension. Then, 10% dilute sulfuric acid solution was added at a water glass solution:dilute sulfuric acid solution weight ratio of 4:1, and the mixture was reacted for 30 min to directly obtain a gel. The gel was washed with deionized water, and the filter cake was flash-dried to obtain modified silica gel micropowder DW3. Silica gel micropowder DW3, diatomaceous earth, clay, and water were mixed in a weight ratio of 54:18:18:10 to obtain a dechlorination agent precursor. The dechlorination agent precursor was mixed with sodium cellulose powder at a mass ratio of 1:0.04, and the mixture was extruded into strips. The strips were then dried at 120℃ for 2 h and calcined at 500℃ for 3 h to obtain the dechlorination agent, namely, dechlorination agent D3.

[0089] Example 11

[0090] The dechlorinating agents prepared in the above examples and comparative examples were tested for their effectiveness in simultaneously removing organic and inorganic chlorine. The test results are shown in Table 1.

[0091] A certain amount of dichloroethane was dissolved in reformed oil with a hydrogen chloride content of 100 mg / L to prepare a simulated feedstock oil with an organochlorine content of 100 mg / L and a hydrogen chloride content of 100 mg / L. The above dechlorinating agent was ground to 20-40 mesh particles, and 3 g was accurately weighed using an analytical balance and filled into a reactor with an inner diameter of 10 mm and a volume of 4 mL. Both ends of the reactor were plugged with quartz wool. The reactor was incubated at 70°C, atmospheric pressure, and a liquid hourly space velocity of 4–10 h⁻¹. -1 Under these conditions, a dynamic dechlorination experiment was conducted by passing simulated feedstock oil through the reactor containing the dechlorinating agent, and the chlorine content in the simulated feedstock oil at the outlet was measured. A chlorine content ≤0.5 mg / L at the outlet was considered breakthrough.

[0092] Table 1. Results of breakthrough chlorine capacity test of samples in reformate oil.

[0093]

[0094]

[0095] When the space velocity increases, the chlorine capacity decreases slightly, but it is still significantly higher than that of the prior art, indicating that the active component in this invention has a high content and high utilization rate, and performs a better dechlorination effect under liquid phase conditions.

[0096] Example 12

[0097] Compared to alkane components, alkenes are more reactive due to their polarity. When in contact with dechlorinating agents, alkenes readily undergo side reactions with the active components of the dechlorinating agent, generating organochlorides or carbon deposits. When the pore size distribution is biased towards a microporous structure, the occurrence of side reactions is more prevalent. The generated organochlorides and carbon deposits not only consume the limited content of active components but also have the disadvantage of clogging mass transfer channels, thus significantly reducing the chlorine penetration capacity of the chloride scavenger. To investigate the effect of carbon deposits on the chlorine penetration capacity of the chloride scavenger, a high-frequency infrared carbon-sulfur analyzer was used to compare the carbon content of the samples before and after dechlorination evaluation in Example 11. Before testing, the evaluated samples underwent a 200°C drying step to remove adsorbed residual hydrocarbon components. The test results are shown in Table 2. In Table 2, sample S8 showed the lowest carbon deposit content, only 0.03 wt%, and the increase in carbon deposit content after dechlorination was minimal, indicating that the dechlorinating agent is adaptable to different hydrocarbon systems and that side reactions during the dechlorination process are suppressed.

[0098] Table 2 Comparison of C content before and after dechlorination performance evaluation of samples

[0099]

[0100]

[0101] Example 13

[0102] The modified silica gel micropowders of Examples 1-10 and Comparative Examples 1-3 were tested using an ASAP2020 physical adsorption analyzer. The test method employed was low-temperature nitrogen adsorption-desorption. The measured specific surface area, pore volume, and pore size data of the samples are shown in Table 3.

[0103] Table 3

[0104]

[0105] This invention utilizes nano-sized zinc oxide or zinc carbonate and other active components highly dispersed in water glass, followed by rapid reaction with dilute sulfuric acid to prepare micron-sized modified silica gel powder. This powder is then mixed with inorganic macroporous materials and clay binders to form a highly active, large-pore, large-volume liquid-phase dechlorinating agent. Due to the in-situ high dispersion of the dechlorination active components, the large pore size improves liquid-phase diffusion, and the large pore volume enhances dechlorination capacity. This invention is suitable for the removal of inorganic or organic chlorine from oils, especially for the removal of hydrogen chloride or organic chlorine from reformed oils, exhibiting high dechlorination efficiency and precision in the liquid-phase dechlorination process.

[0106] The above description of the embodiments is provided to enable those skilled in the art to understand and use the invention. It will be apparent to those skilled in the art that various modifications can be made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present invention is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present invention without departing from the scope of the invention should be within the protection scope of the present invention.

Claims

1. A macroporous liquid-phase dechlorination agent, characterized in that, Includes the following components by weight: 45-70 parts of dechlorination active substance M modified silica gel micro powder; 15-25 parts of inorganic macroporous material; 15-25 parts clay; The dechlorination active substance M is selected from one or more of the elements Ca, Mg, and / or Zn, Fe, and Cu; In the dechlorination active material M modified silica gel micro powder, the weight ratio of the oxide of the dechlorination active material M to the weight of SiO2 in the silica gel micro powder is (10-20):(80-90). The dechlorination active material M modified silica gel micropowder has a pore volume of 1.7–2.8 mL / g and a specific surface area of ​​300–360 m². 2 / g, average pore size 25-30nm, average particle size 1-2μm; The preparation method of the dechlorination active substance M modified silica gel micro powder includes the following steps: (1) Under stirring, the dechlorination active substance M is added to a diluted water glass solution to form a stable suspension, and then reacted rapidly with a diluted sulfuric acid solution at 10-25°C for 10s-1min to obtain a liquid. (2) The above liquid is sprayed into an alcohol solution with a water content of 6-10 wt% by spray molding, aged for 10-30 min, filtered, and washed to obtain a water-containing filter cake. (3) The water-containing filter cake is flash-dried at 150-200℃ to obtain the dechlorination active material M modified silica gel micro powder; The stirring conditions described in step (1) are high-speed stirring at 2000-2500 r / min; In step (1), the concentration of SiO2 in the diluted water glass solution is 6-8 wt%, and the concentration of H2SO4 in the diluted sulfuric acid solution is 6-8 wt%. The alcohols mentioned in step (2) are selected from one or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, tert-butanol, and n-pentanol; The moisture content of the filter cake is 63-67 wt%. The weight ratio of the diluted water glass solution to the diluted sulfuric acid solution is 3 to 5:1; Using macroporous liquid-phase dechlorinating agents for dechlorination of liquid-phase streams; The liquid phase stream includes light oil or product oil from a catalytic reforming process; The dechlorination process conditions include: a treatment temperature of room temperature to 100°C; and a liquid hourly space velocity of 0.5 to 10 h⁻¹. -1 The reaction pressure is atmospheric pressure to 2 MPa. The macroporous liquid-phase dechlorinating agent is suitable for removing inorganic or organic chlorine from oil products.

2. The macroporous liquid-phase dechlorination agent according to claim 1, characterized in that, The inorganic macroporous material is selected from one or more of diatomaceous earth, hydrotalcite, and pseudoboehmite.

3. The macroporous liquid-phase dechlorination agent according to claim 1, characterized in that, The dechlorination active substance M is selected from one or more of oxides, carbonates, or hydroxides.

4. The macroporous liquid-phase dechlorination agent according to claim 3, characterized in that, The dechlorination active substance M is selected from one or more of zinc oxide, zinc carbonate, copper carbonate, calcium carbonate, and iron hydroxide.

5. A method for preparing a macroporous liquid-phase dechlorination agent according to any one of claims 1 to 4, characterized in that, The dechlorination active substance M modified silica gel micro powder, inorganic macroporous material, clay and water are uniformly mixed and shaped, dried at 60-200℃ for 40 minutes to 10 hours, and then further activated at 300-600℃ for 20-200 minutes to prepare the macroporous liquid phase dechlorination agent.

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