Auxiliary agent for removing trace chloride in oil product and recovery method thereof

Abstract

The invention belongs to the technical field of dechlorination purification of whole generated oil, and discloses an assistant for removing trace chlorides in an oil product and a recovery method thereof.The assistant comprises a component 1 and a component 2, the component 1 comprises at least one of an A type molecular sieve, an X molecular sieve, a ZSM molecular sieve and a Y molecular sieve, and the weight content of the component 1 in the dechlorination assistant is 30%-50%; component 2: an organic chlorine adsorbent which is mainly selected from at least one of activated carbon powder, diatom ooze, porous carbon, sepiolite, bamboo charcoal and charcoal, and the weight content of the organic chlorine adsorbent is 10-30%; the component 3 is an auxiliary component which is selected from at least one of alkali metals, and the weight content of the auxiliary component in the dechlorination auxiliary is 3%-10%; the component 4 is a binder, silica sol or aluminum sol is selected, and the weight content of the binder is 20%-40%; and a component 5: a pore-enlarging agent, an extrusion aid and other components, wherein the weight content of the component 5 is 3-10%. The preparation method disclosed by the invention is simple, the required materials are simple and easy to obtain, the cost is low, the effect is good, the recycling process is simple, the energy consumption is low, the recycling effect is relatively good, and the application prospect is wide.

Description

Technical Field

[0001] The present invention relates to the technical field of dechlorination and purification of light oil products, such as reforming oil, and relates to an auxiliary agent for removing trace chlorides in oil products and a recovery method thereof, and specifically to a recoverable dechlorination auxiliary agent for removing chlorides (including organic chlorine and inorganic chlorine) in oil products at low temperature, a preparation method thereof and a recovery method thereof. The auxiliary agent has many advantages such as simple preparation and recovery process, low cost, good use effect, and low energy consumption during use. Background Art

[0002] There are two sources of chlorine in the catalytic reforming process: one is the chloride (mostly organic chloride) added during crude oil extraction to increase oil recovery. The other is the addition of water and organic chloride during the reforming reaction to maintain the high reaction activity of the reforming catalyst. In the actual production of the reforming unit, the chloride in the material will cause strong corrosion to the aromatics unit and cause environmental pollution, which is extremely harmful. In order to slow down the corrosion of equipment and pipelines and reduce the impact on downstream products, solid dechlorination technology is often used in the reforming unit, and different dechlorinating agents are used according to the changes in the raw materials and operating conditions of each part.

[0003] CN101269294A discloses a low-temperature zinc-calcium dechlorinating agent and a preparation method thereof. The dechlorinating agent comprises an active component and a carrier. The active component is active ZnO, Ca(OH) 2 or light CaCO 3 The mixture is formed, and the carrier is clay and aluminate cement. The invention solves the problem that the dechlorinating agent cannot achieve high chlorine capacity at low temperature and cannot achieve high dechlorination effect. CN104437342A discloses a high chlorine capacity liquid phase dechlorinating agent and its preparation method and application. In the application of low temperature and low chlorine reforming oil liquid phase dechlorination, it has the characteristics of large chlorine capacity, water resistance, long service life, etc. The liquid phase dechlorinating agent uses carbon molecular sieve as a carrier and alkali metal oxide as an active component.

[0004] CN103127903A invents a low-temperature dechlorination agent, which solves the problem of excessive consumption of capacity due to roasting in the preparation process of the dechlorination agent in the prior art. It further provides a low-temperature dechlorination agent with a simple preparation method, low cost and high chlorine capacity. It is prepared by using ferrous sulfate, calcium oxide and attapulgite clay.

[0005] CN105542836B mentions a high-precision liquid-phase dechlorination agent, which uses modified activated carbon as a carrier, optimizes the pore structure of the activated carbon, and enhances the binding degree with the active components. It can remove polar HCl, is more conducive to stabilizing the adsorbent, and improves the dechlorination accuracy.

[0006] CN103571521B discloses a method for removing chlorine-containing organic compounds from oil products. A dechlorinating agent is dissolved in N,N-dimethylformamide to obtain a dechlorinating agent solution, the dechlorinating agent solution is mixed with the oil product for dechlorination reaction, and after the reaction is completed, the N,N-dimethylformamide is separated, water is added to the residue to extract water-soluble chlorine-containing compounds, and the water phase is separated to obtain a dechlorinated product.

[0007] CN104560126A discloses a dechlorinating agent for removing chloride ions from reformed gasoline and a dechlorination method thereof. The dechlorinating agent is composed of a composite carrier with rich microporous structure and a variety of dechlorination active substances. During dechlorination, the dechlorinating agent and reformed gasoline are in reverse contact, the reaction temperature is between room temperature and 120°C, and the pressure is between normal pressure and 8.0MPa. The chloride ions in the reformed gasoline can be effectively removed, and the dechlorinating agent has a long service life.

[0008] The above disclosed dechlorination aids also have the following technical problems:

[0009] 1. It does not mention whether the dechlorinating agent can be recycled and how to recycle it; 2. The synthesis process is complicated, which increases production costs; 3. It cannot remove both organic chlorine and inorganic chlorine at the same time; 4. It is not suitable for the current low-temperature liquid phase method for removing chlorides from light oil products. Summary of the invention

[0010] In order to solve the problems existing in the prior art, the present invention provides an oil dechlorination auxiliary agent with a simple preparation method, simple and easy-to-obtain required materials, low cost, good effect, simple recycling process, low energy consumption and good recycling effect. The chlorine compounds in oil products can be removed at low temperature. The chlorine compounds include organic chlorine and inorganic chlorine, and can be recycled and reused under specific conditions, thereby achieving the purpose of reducing equipment corrosion while reducing the operating costs of the device, and has broad application prospects.

[0011] The main purpose of the present invention is to provide a dechlorination auxiliary agent for removing chlorides from oil products by low-temperature adsorption, a preparation method and a recovery method thereof. The dechlorination agent has good use effect, low cost, simple preparation process, low reaction energy consumption, and can be recycled and reused. After simple device modification, online regeneration technology can be experimented, and the dechlorination agent has a very broad prospect.

[0012] There are two main sources of chlorine in the reformed oil. One is the injection of chlorine during crude oil extraction. The other is that in order to maintain the activity of the reforming catalyst, a certain amount of chlorine compounds, such as perchloroethylene, needs to be artificially injected. Perchloroethylene is not completely decomposed during the reforming reaction and will produce dichloroethylene. The reforming process belongs to the water-chlorine balance operation process. The reformed oil contains a trace amount of water, and the inorganic chlorine in the reformed oil will dissolve in this part of water. The present invention utilizes this phenomenon and adopts a molecular sieve that can adsorb and remove water. In the process of adsorbing and removing water, because the pores are 4 to 5A, the diameters of water molecules and HCl molecules can just enter the pores, thereby achieving the effect of adsorbing and removing inorganic chlorine. By selecting a suitable adsorbent, dichloroethylene and other olefins can be adsorbed and removed to achieve the purpose of removing organic chlorine.

[0013] By removing inorganic chlorine and water through molecular sieve adsorption, and selecting suitable adsorbents to remove ethylene dichloride and other olefins, regeneration can be carried out under certain conditions to achieve the purpose of regenerating the dechlorinating agent. Molecular sieves have a high specific surface area and thus a strong adsorption capacity. 5A molecular sieves can adsorb 22% of their own weight of impurities, so that the dechlorinating agent has a high chlorine capacity and adsorption capacity.

[0014] In addition, the selection of metal loaded by the dechlorination agent is mainly based on the - The reaction rate of metal and Cl - Reaction speed, first ionization energy is more important, the smaller the first ionization energy, the easier it is for the atoms of the element to lose electrons, the stronger the metallicity, and the easier it is for the reaction to proceed. The size of the ionization energy depends mainly on the nuclear charge, atomic radius and the electron layer structure of the atom. Among the alkali metals that can react with Cl-, the first ionization energy of Na and K is very low, proving that they are very easy to lose electrons, thereby combining with HCl. So the present invention mainly adopts these two metals as synthesis components.

[0015] According to the above theoretical research, the present invention provides an auxiliary agent for removing trace chlorides from oil products, and the dechlorination auxiliary agent includes: component 1: at least one of type A molecular sieve, X molecular sieve, ZSM molecular sieve and Y molecular sieve, and the weight content of the active component in the dechlorination auxiliary agent is 30% to 50%; component 2: organic chlorine adsorbent, mainly selected from at least one of activated carbon powder, diatom mud, porous carbon, sepiolite, bamboo charcoal, and charcoal, with a weight content of 10% to 30%; component 3: auxiliary agent component, the auxiliary agent component is selected from at least one of alkali metals, and the weight content of the auxiliary agent component in the dechlorination auxiliary agent is 3% to 10%; component 4: binder, selected from silica sol or aluminum sol, with a weight content of 20% to 40%; component 5: other components such as pore expander and extrusion aid, with a weight content of 3% to 10%.

[0016] Furthermore, the molecular sieve of component 1 has a pore size of 4 to 5A, and more preferably has a mesh size of >200 meshes and a specific surface area of ​​>200m 2 / g, is selected from at least one of 5A molecular sieve, 13X molecular sieve, ZSM-5 molecular sieve and NaY molecular sieve.

[0017] Furthermore, component 2 is one or more of activated carbon powder, diatom mud, porous carbon, sepiolite, bamboo charcoal, and charcoal, among which coconut shell activated carbon powder is preferred.

[0018] Furthermore, the binder is silica sol and / or alumina sol; preferably alumina sol prepared from pseudo-boehmite, and the weight content of the binder in the liquid phase dechlorination agent is preferably 25% to 35%.

[0019] Furthermore, the precursor of the auxiliary agent component is a soluble salt, preferably a soluble nitrate or a soluble carbonate, and the type of the salt is preferably Na and / or K.

[0020] A method for preparing an auxiliary agent for removing trace chlorides from oil products comprises the following steps:

[0021] After components 1, 2, 3 and 5 are uniformly mixed, component 4 is added, mixed and stirred, and kneaded into shape; the obtained mixture is extruded to obtain an auxiliary agent precursor; the dechlorination auxiliary agent precursor is dried at 80-120° C. for 1-2 hours, and after drying, it is calcined at 500-600° C. for 2-4 hours to obtain the dechlorination auxiliary agent.

[0022] When used, the dechlorination treatment temperature is a low temperature condition of 20 to 30°C, no heating treatment is required, the reaction pressure is 1-5MPa, preferably 2 to 3Mpa; the mass space velocity is 2 to 10h -1 , preferably 3 to 6 hours -1 ; The reactor height-to-diameter ratio is 1 to 6:1, preferably 3 to 5:1.

[0023] A method for recovering an auxiliary agent for removing trace chlorides from oil products comprises the following steps:

[0024] After the dechlorination agent is used, N is purged in a closed container at room temperature. 2 After 2 hours, heating was started and maintained at N 2 Purge, maintain the temperature at 200-300°C for 2-4 hours, then cool down and keep N 2 Purge until cooled to room temperature.

[0025] The beneficial effects of the present invention compared with the prior art are:

[0026] The preparation method of the invention is simple, the required materials are simple and easy to obtain, the cost is low, the effect is good, and the recycling process is simple, the energy consumption is low, the recycling effect is good, and it has broad application prospects. DETAILED DESCRIPTION

[0027] The beneficial effects of the present invention will be further described below in conjunction with specific embodiments. Unless otherwise specified, the experimental methods used in the present invention are all conventional methods, and the experimental equipment, materials, reagents, etc. used can be obtained from commercial channels.

[0028] Example 1

[0029] 90 mL of deionized water was added to 78 g of pseudo-boehmite, and then mechanically stirred. After stirring for 30 minutes, 5 mL of concentrated nitric acid was gradually added dropwise to obtain a viscous paste-like substance, namely, a binder.

[0030] 50.0 g of molecular sieve, 20.0 g of carbon powder, 5.0 g of sodium nitrate, 5.0 g of sesbania powder (extrusion aid) and 40.0 g of the synthesized binder were mixed evenly, combined and formed into strips, dried at 100° C. for 2 hours, and calcined at 550° C. for 4 hours to obtain additive A.

[0031] Example 2

[0032] 60.0 g of molecular sieve, 10.0 g of carbon powder, 5.0 g of sodium nitrate, 5.0 g of sesbania powder (extrusion aid) and 30.0 g of the synthesized binder were mixed evenly, combined and formed into strips, dried at 120° C. for 2 hours, and calcined at 550° C. for 4 hours to obtain additive B.

[0033] Example 3

[0034] 70.0 g of molecular sieve, 10.0 g of carbon powder, 2.5 g of sodium nitrate, 2.5 g of sesbania powder (extrusion aid) and 25.0 g of the synthesized binder were mixed evenly, combined and formed into strips, dried at 120° C. for 2 hours, and calcined at 550° C. for 4 hours to obtain additive C.

[0035] The evaluation results of the above three dechlorination samples are as follows:

[0036] Table 1: Evaluation results of dechlorination aids

[0037]

[0038] The above three samples were added to the reformed oil prepared with HCl for static adsorption. The salt content in the oil was tested every day. When the salt content no longer decreased, it was considered that the dechlorination aid had reached saturation in adsorbing chlorine. After the dechlorination aid was taken out, the surface oil was dried in the shade, and the saturated chlorine content in the dechlorination aid was tested. The results are shown in the following table:

[0039] Table 2: Absorbed chlorine content in dechlorination aid

[0040] Dechlorination aid A B C Saturated chlorine content, % 15.5 18.1 20.2

[0041] The above three samples were recycled under different conditions. The samples were placed in a tube furnace at N 2 After heating under purging conditions and cooling to room temperature, the chlorine content in the dechlorination agent is tested. The recovered dechlorination agent is then placed in the reforming oil with a high chlorine content and soaked. When the salt content in the reforming oil no longer decreases, the dechlorination agent is taken out to test the chlorine content. The results are as follows:

[0042] Table 3: Recovery of dechlorination additives

[0043]

[0044] From the above results, it can be seen that the dechlorination auxiliary agent has a good recovery effect and can achieve the purpose of reuse.

[0045] Example 4

[0046] 90 mL of deionized water was added to 78 g of pseudo-boehmite, and then mechanically stirred. After stirring for 30 minutes, 5 mL of concentrated nitric acid was gradually added dropwise to obtain a viscous paste-like substance, namely, a binder.

[0047] 50.0 g of molecular sieve, 20.0 g of diatom mud, 5.0 g of potassium nitrate, 5.0 g of sesbania powder (extrusion aid) and 40.0 g of the synthesized binder were mixed evenly, combined and formed into strips, dried at 100° C. for 2 hours, and calcined at 550° C. for 4 hours to obtain dechlorination aid D.

[0048] Example 5

[0049] 60.0 g of molecular sieve, 10.0 g of diatom mud, 5.0 g of potassium nitrate, 5.0 g of sesbania powder (extrusion aid) and 30.0 g of the synthesized binder were mixed evenly, combined and formed into strips, dried at 120° C. for 2 hours, and calcined at 550° C. for 4 hours to obtain dechlorination aid E.

[0050] Example 6

[0051] 70.0 g of molecular sieve, 10.0 g of diatom mud, 2.5 g of potassium nitrate, 2.5 g of sesbania powder (extrusion aid) and 25.0 g of the synthesized binder were mixed evenly, combined and formed into strips, dried at 120° C. for 2 hours, and calcined at 550° C. for 4 hours to obtain dechlorination aid F.

[0052] The evaluation results of the above three dechlorination samples are as follows:

[0053] Table 4: Evaluation results of dechlorination aids

[0054]

[0055] The above three samples were placed in reforming oil prepared with HCl for static adsorption. The salt content in the oil was tested every day. When the salt content no longer decreased, it was considered that the dechlorination aid had reached saturation in adsorbing chlorine. After the dechlorination aid was taken out, the surface oil was dried in the shade, and the saturated chlorine content in the dechlorination aid was tested. The results are shown in the following table:

[0056] Table 5: Absorbed chlorine content in dechlorination aid

[0057] Dechlorination aid D E F Saturated chlorine content, % 15.5 18.1 20.2

[0058] The above three samples were recycled under different conditions. The samples were placed in a tube furnace at N 2 After heating under purging conditions and cooling to room temperature, the chlorine content in the dechlorination agent is tested. The recovered dechlorination agent is then placed in the prepared reforming oil with a high salt content and immersed. When the salt content in the reforming oil no longer decreases, the dechlorination agent is taken out to test the chlorine content. The results are as follows:

[0059] Table 6: Recovery of dechlorination additives

[0060]

[0061] From the above results, it can be seen that the dechlorination auxiliary agent has a good recovery effect and can achieve the purpose of reuse.

[0062] The above-described embodiments are only preferred embodiments of the present invention, but not all feasible embodiments of the present invention. For those skilled in the art, any obvious changes made thereto without departing from the principles and spirit of the present invention should be considered to be included in the scope of protection of the claims of the present invention.

Claims

1. An auxiliary agent for removing trace chlorides from oil products. It is characterized in that Composition includes: Component 1: molecular sieve, with a weight content of 30% to 50%, including at least one of type A molecular sieve, X molecular sieve, ZSM molecular sieve and Y molecular sieve; Component 2: organic chlorine adsorbent, i.e. powder having the ability to adsorb olefins, with a weight content of 10% to 30%; Component 3: an auxiliary component, with a weight content of 3% to 10%, including at least one of the alkali metals; Component 4: a binder, with a weight content of 20% to 40%, including silica sol or alumina sol; Component 5: including pore-enlarging agent and auxiliary agent, with a weight content of 3% to 10%.

2. The auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that The molecular sieve has a pore size of 4-5A and is at least one of a 5A molecular sieve, a 13X molecular sieve, a ZSM-5 molecular sieve and a NaY molecular sieve.

3. The auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that The organic chlorine adsorbent is one or more of activated carbon powder, diatom mud, porous carbon, sepiolite, bamboo charcoal and charcoal.

4. The auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that The binder is silica sol and / or alumina sol.

5. The auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that The precursor of the auxiliary agent component is a soluble salt.

6. The method for preparing the auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that After mixing component 1, component 2, component 3 and component 5 evenly, add component 4, mix, stir and knead to form; the obtained mixture is extruded to obtain a dechlorination auxiliary agent precursor; The dechlorination aid precursor is dried and then calcined to obtain the dechlorination aid.

7. The method for preparing an auxiliary agent for removing trace chlorides from oil products according to claim 6, It is characterized in that The dechlorination auxiliary agent precursor is dried at 80-120° C. to obtain the dried precursor, and the drying time is preferably 1-2 hours.

8. The method for preparing an auxiliary agent for removing trace chlorides from oil products according to claim 6, It is characterized in that The dried precursor is calcined to obtain the dechlorination auxiliary agent; the calcination temperature is 500-600° C. and the calcination time is 2-4 hours.

9. The method for recovering an auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that After the dechlorination agent is used, N is purged in a closed container at room temperature. 2 After 2 hours, heating was started and maintained at N 2 Purge, maintain the temperature at 200-300°C for 2-4 hours, then cool down and keep N 2 Purge until cooled to room temperature.

10. Use of the auxiliary agent for removing trace chlorides from oil products according to claim 1, It is characterized in that The dechlorination treatment temperature is 20-30°C, the reaction pressure is 1-5MPa, and the mass space velocity is 2-10h -1 The reactor height-to-diameter ratio is 1 to 6:1.

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