CN113736507A

CN113736507A - Liquid-phase dechlorinating agent, preparation method and application thereof

Info

Publication number: CN113736507A
Application number: CN202010463290.9A
Authority: CN
Inventors: 曹志涛; 王健; 张晓琳; 张元礼; 程光剑; 桂建舟; 解洪新; 李凤生; 王洪星; 吕洁; 李民; 张英杰; 董大清; 莫娅南; 李�学; 高原; 黄集钺; 刘丹; 刘成伟; 彭海龙
Original assignee: Petrochina Co Ltd
Current assignee: Petrochina Co Ltd
Priority date: 2020-05-27
Filing date: 2020-05-27
Publication date: 2021-12-03
Anticipated expiration: 2040-05-27
Also published as: CN113736507B

Abstract

The invention provides a liquid-phase dechlorinating agent, a preparation method and application thereof. The liquid-phase dechlorinating agent comprises: the active component is selected from at least one of an A-type molecular sieve, a 13X molecular sieve and a NaY molecular sieve, and the weight content of the active component in the liquid-phase dechlorinating agent is 20-40%; the auxiliary agent component is selected from at least three of copper oxide, sodium oxide, potassium oxide, barium oxide, calcium oxide, magnesium oxide, zinc oxide and iron oxide, and the weight content of the auxiliary agent component in the liquid-phase dechlorinating agent is 3-10%; the carrier is used for loading active components and auxiliary components, the carrier is carbon powder, and the weight content of the carbon powder in the liquid-phase dechlorinating agent is 10-33%; and the balance of binder. The carbon powder has more adsorption sites, large pore volume and specific surface area, and the surface of the activated carbon powder has a plurality of oxygen-containing functional groups, so that the polarity of the carrier is improved, the bonding strength between the carrier and the active component is increased, and the loss of the active component is reduced to keep higher chlorine capacity.

Description

Liquid-phase dechlorinating agent, preparation method and application thereof

Technical Field

The invention relates to the technical field of liquid phase purification, in particular to a liquid phase dechlorinating agent, and a preparation method and application thereof.

Background

Sources and hazards of chlorine in the catalytic reforming process: firstly, chloride (mostly organic chloride) is added frequently when crude oil is produced to improve oil recovery. The chlorine content in the crude oil is increased along with the increase of the oil recovery rate. Under the condition of high temperature, the organic chlorine can be converted into inorganic hydrogen chloride, so that the inorganic hydrogen chloride has a great corrosion effect on pipelines, and if ammonia exists at the downstream, the organic chlorine can react to generate ammonium chloride, so that equipment is blocked, and the operation of the device is influenced. Secondly, in the reforming reaction process, chlorine on the reforming catalyst is continuously lost, and the reforming catalyst needs to have certain acidity in order to maintain higher reaction activity, so that water and organic chloride need to be continuously added, the content of chlorine in crude oil is further increased, and the corrosion of pipelines and the blockage of equipment are accelerated. Therefore, it is necessary to prepare a dechlorinating agent with high efficiency.

The use of dechlorinating agents is the main method for removing hydrogen chloride from materials. At present, dechlorinating agents are mainly classified into two types: one is a gas phase dechlorinating agent, and CN105617853A discloses a high-temperature gas phase dechlorinating agent which is prepared from calcium carbonate, magnesium carbonate, calcium oxide and aluminate cement, and has low strength, short service cycle and improved chlorine capacity. The other is a liquid-phase dechlorinating agent, namely a dechlorinating agent for liquid-phase materials, and the dechlorinating effect of the liquid-phase dechlorinating agent is poorer than that of a gas-phase dechlorinating agent because the mass transfer rate in a liquid-phase system is lower, and CN105542836A discloses a liquid-phase dechlorinating agent, and the chlorine capacity of the dechlorinating agent prepared from CuO, CaO, KOH and activated carbon is only 16%.

As mentioned above, the reformed oil has a low chlorine content, and when liquid phase dechlorination is used, the chlorine capacity of the dechlorinating agent is generally low. The reforming process belongs to a water-chlorine balance operation process, the reformed oil also contains a small amount of water, the water has great influence on a dechlorinating agent taking alkali metal as an active component, and the water can generate a matching reaction with dechlorinating substances (such as calcium chloride, magnesium chloride and the like) to cause the structure damage of the dechlorinating agent, the internal pore canal blockage and the final reduction of the chlorine capacity. Although the physical and chemical parameters (such as specific surface area, pore volume, pore distribution and the like) of the invented liquid-phase dechlorinating agent are ideal, the chlorine volume of the dechlorinating agent is still low when the dechlorinating agent is applied, and particularly the dechlorinating agent taking an alkaline earth metal compound as an active component has poor water resistance. The control standard of the mass fraction of chlorine capacity of the liquid-phase dechlorinating agent developed at home at present is in the range of 8% -15%, but according to the actual situation, the chlorine capacity of the existing liquid-phase dechlorinating agent in the practical application is below 2%, the long-term operation and use of the device cannot be met, the service cycle of some dechlorinating agents is only 1-2 months, and the condition that the content of outlet chlorine is higher than that of inlet chlorine is caused because chlorine is desorbed from the dechlorinating agent.

Besides being related to the nature of the dechlorinating agent, the chlorine capacity is also closely related to the operating temperature. The research shows that: for liquid phase dechlorination, the higher the temperature, the greater the chlorine capacity. For the dechlorination of the reformate oil phase, the operation temperature is limited, generally can not exceed 100 ℃, preferably does not exceed 70 ℃, and in the engineering design and application of the liquid phase dechlorination technology of the catalytic reforming device of 60 ten thousand/a introduced by Qingyang petrochemical company 60 ten thousand/a and Hongkong, and the like, the liquid phase dechlorinating agent is recommended to have a chlorine capacity of less than 12% when the liquid phase dechlorination agent is operated at 50 ℃; operating at 75 ℃, the chlorine capacity is about 20%; the chlorine capacity was about 30% when operating at 100 ℃. Meanwhile, the chlorine content in the reformed oil is low, and the raw material contains a small amount of water, so that the conventional liquid-phase dechlorinating agent has poor effect when being used for dechlorinating the reformed oil, and mainly has the characteristics of low chlorine content, short operation period and the like. For example, the chlorine capacity of a liquid-phase dechlorinating agent developed by foreign companies adopted by Fujian refineries can only reach 3 percent and is far lower than the control index; the PCL-100 molecular sieve adsorbent developed by UOP company is used for dechlorination of reformed oil in liquid phase, and the service life is only 3 months.

CN103830996A discloses a high-efficiency dechlorinating agent. The antichlor is prepared from glucose and CaNO₃、Mg(NO₃)₂、Zn(NO₃)₂、NaHCO₃More than one of the active components are mixed, the carrier and the auxiliary agent are ZSM-5 molecular sieve, methylcellulose is used as a binder, and the active components are mixedDropwise adding the salt of the property component on the processed carrier and the auxiliary agent, then rotating, heating, drying, roasting, forming and then granulating to obtain the product. CN1088388C discloses a dechlorinating agent. The dechlorinating agent is prepared by taking compounds of sodium, calcium and zinc as active components, taking kaolin or montmorillonite, bentonite and diatomite as carriers, kneading, extruding into strips, and roasting at the temperature of 350-400 ℃. However, none of the above dechlorinating agents are equally suitable for use in the liquid phase dechlorination of reformate.

Generally, a carbonaceous carrier (e.g., activated carbon, etc.) has a weak force with respect to an active metal component, which is advantageous in that the reactivity of the active metal component can be improved, but has a disadvantage in that the loss of the active metal component is easily caused, particularly, under a liquid-phase reaction condition, which is more severe, and the loss is further increased if water is present in a liquid-phase material. When the carrier is used in dechlorinating agent, the chlorine capacity is reduced and the service life is shortened.

Disclosure of Invention

The invention mainly aims to provide a liquid-phase dechlorinating agent, a preparation method and application thereof, and aims to solve the problem of low chlorine capacity of the liquid-phase dechlorinating agent in the prior art.

In order to achieve the above object, according to one aspect of the present invention, there is provided a liquid-phase dechlorinating agent comprising: the active component is selected from at least one of an A-type molecular sieve, a 13X molecular sieve and a NaY molecular sieve, and the weight content of the active component in the liquid-phase dechlorinating agent is 20-40%; the auxiliary agent component is selected from at least three of copper oxide, sodium oxide, potassium oxide, barium oxide, calcium oxide, magnesium oxide, zinc oxide and iron oxide, and the weight content of the auxiliary agent component in the liquid-phase dechlorinating agent is 3-10%; the carrier is used for loading active components and auxiliary components, the carrier is carbon powder, and the weight content of the carbon powder in the liquid-phase dechlorinating agent is 10-33%; and the balance of binder.

Further, the binder is silica sol and/or aluminum sol; the content of the binder in the liquid-phase dechlorinating agent is preferably 30-55% by weight.

Further, the carbon powder is carbon powder with the average pore diameter less than or equal to 50 nm; average pore diameter of preferred carbon powder4 to 15nm, and more preferably, the specific surface area of the carbon powder is 200 to 300m²/g。

According to a second aspect of the present application, there is also provided a method of preparing a liquid phase dechlorination agent, the method comprising: dipping a solution prepared from a precursor of the auxiliary agent component on carbon powder to obtain a first mixture; drying the first mixture, and mixing the dried first mixture with an active component and a binder to obtain a second mixture; extruding the second mixture to form a dechlorinating agent precursor; roasting the dechlorinating agent precursor to obtain a liquid-phase dechlorinating agent; wherein, the auxiliary component is selected from at least one of copper oxide, zinc oxide and ferric oxide, and the active component is selected from at least one of A-type molecular sieve, 13X molecular sieve and NaY molecular sieve.

Further, the precursor of the auxiliary component is a soluble salt, preferably a soluble nitrate or a soluble acetate.

Further, the step of calcining the dechlorination agent precursor to obtain a liquid-phase dechlorination agent comprises: drying the dechlorination agent precursor to obtain a dried precursor; and roasting the dried precursor to obtain the liquid-phase dechlorinating agent.

Further, the dechlorination agent precursor is dried at the temperature of 80-120 ℃ to obtain a dried precursor, and the preferable drying time is 3-5 h.

Further, roasting the dried precursor in a nitrogen atmosphere to obtain a liquid-phase dechlorinating agent; preferably, the roasting temperature is 350-650 ℃, and the roasting time is 1-6 h.

Further, the roasting temperature is 450-600 ℃, and the roasting time is 3-5 h.

According to a third aspect of the present application, there is also provided the use of any one of the above liquid phase dechlorinating agents in the dechlorination of reformed oil.

Further, the application is dechlorination under the condition that the reformate is in a liquid phase, and the reformate is preferably dechlorinated without dehydration.

Further, the temperature of dechlorination treatment is 30-80 ℃, and the mass space velocity is 2-10h^-1Preferably 3 to 6 hours^-1(ii) a Preferably, dechlorination treatmentThe reaction is carried out under the pressure of 0.1-3 MPa; the height-diameter ratio of the reactor is 2-8: 1, preferably 3-5: 1.

by applying the technical scheme of the invention, the carbon powder is used as the carrier, the carbon powder has more adsorption sites and large pore volume and specific surface area, which is beneficial to the loading of the auxiliary agent component and the active component on the active carbon powder, and meanwhile, the surface of the active carbon powder has a plurality of oxygen-containing functional groups, so that the polarity of the active carbon powder carrier is improved, the bonding strength between the carrier and the active component can be increased, and the loss of the active component is reduced to keep higher chlorine capacity. Meanwhile, the hydrogen chloride is polar molecules, and is easier to be stably adsorbed in the pore structure of the high-efficiency activated carbon powder carrier with the same larger polarity, so that the dechlorination precision of the dechlorination agent is improved.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

Interpretation of terms:

chlorine capacity: the chlorine capacity is the chlorine bearing capacity of the dechlorinating agent.

Dechlorination precision: namely, the dechlorination effect of the dechlorinating agent is embodied, and the lower the chlorine content of the dechlorinated oil product is, the higher the dechlorinating precision of the dechlorinating agent is.

In view of the problem of low chlorine capacity of the prior art liquid phase dechlorinating agents, in one exemplary embodiment of the present application, there is provided a liquid phase dechlorinating agent comprising: the liquid phase dechlorinating agent comprises an active component, an auxiliary agent component, a carrier for loading the active component and the auxiliary agent component and a binder, wherein the carrier is carbon powder, and the mass content of the carbon powder in the liquid phase dechlorinating agent is 10-33%; the active component is selected from at least one of A-type molecular sieve, 13X molecular sieve and NaY molecular sieve, and the mass ratio content of the active component in the liquid-phase dechlorinating agent is 20-40%; the auxiliary agent component is selected from at least three of copper oxide, sodium oxide, potassium oxide, barium oxide, calcium oxide, magnesium oxide, zinc oxide and ferric oxide, and the mass content of the auxiliary agent component in the liquid-phase dechlorinating agent is 3-10%; the balance being binder.

Provided by the present applicationThe liquid-phase dechlorinating agent has more adsorption sites and large pore volume (such as 0.5-1.2 cm)³A/g) and a large specific surface area (for example, 150 to 600m²The carbon powder of/g) is used as a carrier, which is beneficial to the loading of an auxiliary agent component and an active component on the active carbon powder, and meanwhile, the surface of the active carbon powder has a plurality of oxygen-containing functional groups, so that the polarity of the active carbon powder carrier is improved, the bonding strength between the carrier and the active component can be increased, and the loss of the active component is reduced to keep higher chlorine capacity. Meanwhile, hydrogen chloride is polar molecules, and is easier to be stably adsorbed in the pore structure of the efficient activated carbon powder carrier with the same large polarity, so that the dechlorination precision of the dechlorination agent is improved (the dechlorination precision of the dechlorination agent can reach below 0.5 ppm).

The liquid phase dechlorinating agent has good effect on removing inorganic chlorine in oil products and tetrachloroethane and dichloromethane in organic chlorine, is particularly suitable for removing hydrogen chloride in reformed oil, is also suitable for fine dechlorination in chemical production of synthetic ammonia, methanol and the like, and has wide application range.

In the liquid-phase dechlorinating agent provided by the application, the active component is selected from the molecular sieves in the above categories as the active component, so that the liquid-phase dechlorinating agent has the beneficial effect of effectively removing the organic chloride. On the basis of the active component, at least one of copper oxide, zinc oxide and iron oxide is selected as an auxiliary component, which is beneficial to improving the performance of the active component. The binder is used for molding. The components are reasonably mixed in amount, so that the performances of the components are cooperated, and the liquid-phase dechlorinating agent has high chlorine capacity.

In the liquid-phase dechlorinating agent, the binder is used for binding each component and forming a product, and the specific type and the dosage of the binder can be obtained by reasonably adjusting the existing binder. In a preferred embodiment, the binder is a silica sol or an aluminum sol; the mass content of the binding agent in the liquid-phase dechlorinating agent is preferably 30-55%. The silica sol or the aluminum sol is selected as the binder, so that the method has the advantages of low cost and simple forming process. The silica sol is preferably a silica sol formed by dissolving silica in a nitric acid solution. Preferably, the aluminum sol is one formed by dissolving pseudo-boehmite in nitric acid solution. The specific concentration can be reasonably adjusted according to actual needs.

The carbon powder is used as an adsorption carrier of the active component and the auxiliary component, and preferably has higher pore volume and larger specific surface area in order to better load the active component and the auxiliary component. In a preferred embodiment, the carbon powder is carbon powder with an average pore diameter less than or equal to 50 nm; preferably, the average pore diameter of the carbon powder is 4-15 nm, and more preferably, the specific surface area of the carbon powder is 200-300 m²(ii) in terms of/g. The carbon powder with the pore structure of the microporous structure and the mesoporous structure is preferably selected, has the larger pore volume and the larger specific surface area, and improves the adsorption capacity to the active component and the auxiliary component, so that the carbon powder has stronger binding force with the carrier and is not easy to lose, and the higher chlorine capacity is kept.

In a second exemplary embodiment of the present application, there is provided a process for preparing any one of the liquid phase dechlorinating agents described above, the process comprising: dipping a solution prepared from a precursor of the auxiliary agent component on carbon powder to obtain a first mixture; drying the first mixture, and mixing the dried first mixture with an active component and a binder to obtain a second mixture; extruding the second mixture to form a dechlorinating agent precursor; roasting the dechlorinating agent precursor to obtain a liquid-phase dechlorinating agent; wherein, the auxiliary component is selected from at least one of copper oxide, zinc oxide and ferric oxide, and the active component is selected from at least one of A-type molecular sieve, 13X molecular sieve and NaY molecular sieve.

According to the difference of gas-liquid phase molecular diffusion rate and the special molecular structure of macromolecular hydrocarbon, the preparation method of the liquid phase dechlorinating agent comprises the steps of soaking carbon powder in soluble salt of an auxiliary component precursor, mixing the carbon powder with an active component A type molecular sieve, a 13X molecular sieve or a NaY molecular sieve after drying treatment, kneading and forming by using a binder, and roasting to obtain the dechlorinating agent.

In addition, in the roasting treatment process, the part of the auxiliary agent component, which is in contact with the carrier, can be subjected to partial reduction reaction with carbon element, and after reduction, the auxiliary agent component and carbon powder of the carrier have stronger bonding effect, similar to the alloy structure of metal and carbon, and the mechanism of the auxiliary agent component is probably similar to the carburization effect in the field of metal materials. The structure has strong acting force with the carrier, thereby enhancing the bonding strength between the carrier and the active component and reducing the loss of the active component in the using process. The lack of loss of active ingredient is one of the most important factors for increasing chlorine capacity.

In a preferred embodiment, the precursor of the adjuvant component is a soluble salt, preferably a soluble nitrate or a soluble acetate. The soluble salts of the precursors of copper oxide, zinc oxide and iron oxide are soluble copper salt, soluble zinc salt and soluble iron salt, respectively. And reasonably selecting according to actual needs.

In the preparation method, the roasting step can be obtained by properly adjusting the roasting conditions on the basis of the existing roasting step. In a preferred embodiment, the step of calcining the dechlorination agent precursor to obtain a liquid phase dechlorination agent comprises: drying the dechlorination agent precursor to obtain a dried precursor; and roasting the dried precursor to obtain the liquid-phase dechlorinating agent. Drying and then roasting are carried out, which is helpful for making the roasted structure uniform.

In the step of drying before calcination, the drying manner is not limited. In a preferred embodiment, the dechlorination agent precursor is dried at 80-120 ℃ to obtain a dried precursor, and the drying time is preferably 3-5 h.

In the roasting step, the specific roasting temperature can be reasonably adjusted to obtain the optimal roasting temperature. In a preferred embodiment, the dried precursor is calcined under a nitrogen atmosphere to obtain a liquid phase dechlorinating agent; preferably, the roasting temperature is 350-650 ℃, and the roasting time is 1-6 h. In a more preferred embodiment, the roasting temperature is 450-600 ℃, and the roasting time is 3-5 h.

In a third exemplary embodiment of the present application, there is provided the use of any of the above-described liquid phase dechlorinating agents in the dechlorination of reformed oil. The liquid-phase dechlorinating agent has a good effect of removing inorganic chlorine and organic chlorine in a liquid-phase oil product of reformed oil, and can remove the chlorine content in the oil product to be less than or equal to 0.5 mg/L.

In a preferred embodiment, the application is dechlorination of the reformate in the liquid phase, preferably without dehydration. The liquid-phase dechlorinating agent has a good effect of removing inorganic chlorine and organic chlorine in a liquid-phase oil product of reformed oil, and can remove the chlorine content in the oil product to be less than or equal to 0.5 mg/L. So that the reformed oil can be directly dechlorinated without dehydration.

The specific parameter conditions of the dechlorination treatment can be determined according to the specific process and the process requirements of the reforming process. In a preferred embodiment, the temperature of the dechlorination treatment is 30-80 ℃, and the mass space velocity is 2-10h^-1Preferably 3-6h^-1(ii) a Preferably, the dechlorination treatment is carried out under the pressure of 0.1-3 MPa; the height-diameter ratio of the reactor is 2-8: 1, preferably 3-5: 1. under other conditions, the larger the height-diameter ratio is, the longer the contact time between the dechlorinating agent and the oil product is, and meanwhile, the more uniform the fluid is distributed in the bed layer, the more obvious the dechlorinating effect is, and the dechlorinating efficiency is high.

The advantageous effects of the present application will be further described with reference to specific examples.

Example 1

Adding 6.0g of pseudoboehmite (SB) powder into a nitric acid solution with the concentration of 2mol/L and the volume of 60mL, and stirring for 1h at room temperature to serve as a binder for later use.

Carbon powder (12%) with a mass of 10.0g was added to 5.14g of Mg (NO)₃)₂·6H₂O (0.80 g in terms of MgO) (5.2% of auxiliary), 3.5g of Ca (NO)₃)₂·4H₂O (0.84 g in terms of CaO) and 5.0gCu (NO)₃)₂·3H₂Stirring in an aqueous solution of O (1.70 g calculated by CuO) to fully immerse and mix the O, wherein the properties of the carbon powder are as follows: the average pore diameter is 12.8nm, the specific surface area is 200m²/g。

Stirring and mixing 45g of binder (54%), the carbon powder mixture and 25g (30%) of 13X molecular sieve, kneading and molding the mixture, drying the sample in a drying oven at 120 ℃ for 4 hours, and then stabilizing the sample in a tube furnace at 550 ℃ for 4 hours under a nitrogen atmosphere to obtain a finished dechlorinating agent A.

Example 2

Macromolecular silica particles with a mass of 35.0g were added to a nitric acid solution with a concentration of 5mol/L and a volume of 60mL, and stirred at room temperature for 1h to be used as a binder.

Carbon powder with a mass of 15.0g (13.4%) was added to 7.5g of NaNO₃(with Na)₂2.74g of O (6.25 percent of auxiliary agent) and 3g of Ca (NO)₃)₂·4H₂O (0.72 g in terms of CaO), 5.0g of Cu (NO)₃)₂·3H₂O (1.70 g in terms of CuO) and 3.5g of KNO₃(with K)₂1.90g in terms of O) was added to the mixed aqueous solution and sufficiently immersed with stirring. The carbon powder has the following properties: the average pore diameter is 10.3nm, the specific surface area is 220m²/g。

After the excess liquid was removed, the carbon powder mixture was mixed with a mixture of 65g (58%) nitric acid solution and polymeric silica particles and 25g (22%) 13X molecular sieve with stirring. And then kneading and molding the mixture, putting the sample in a drying oven, drying at 80 ℃ for 4h, and then stabilizing the sample in a tube furnace at 550 ℃ under a nitrogen atmosphere for 4h to obtain a finished dechlorinating agent B.

Example 3

20g of kaolin is added into nitric acid aqueous solution with the concentration of 3mol/L and the volume of 60mL, and the mixture is stirred for 45min at room temperature to be used as a binder for standby.

Carbon powder with a mass of 10.0g (13.7%) was added to 6.5g of Cu (NO)₃)₂·3H₂O (2.21 g in terms of CuO) (auxiliary agent 6.7%), 5.5g of Ca (NO)₃)₂·4H₂O (1.32 g in terms of CaO), 2.3g of Ba (NO)₃)₂The resulting mixture was thoroughly immersed in an aqueous solution (1.35 g in terms of BaO) under stirring. The carbon powder has the following properties: the average pore diameter is 8.5nm, the specific surface area is 240m²/g。

After the excess liquid was removed, the carbon powder mixture was mixed with a mixture of 30g of nitric acid solution and kaolin and 28g (38.4%) of NaY molecular sieve with stirring. And then kneading and molding the mixture, putting the sample in a drying oven, drying at 120 ℃ for 4h, and then stabilizing the sample in a tube furnace at 550 ℃ under a nitrogen atmosphere for 3h to obtain a finished dechlorinating agent C.

Example 4

SB powder with a mass of 30g was added to a nitric acid aqueous solution with a concentration of 3mol/L and a volume of 60mL, and stirred at room temperature for 45min to serve as a binder for future use.

MgSO with a mass of 3.5g₄·7H₂O (1.16 g in terms of MgO) (auxiliary agent 7.4%), and 5.5g of Ca (NO)₃)₂·4H₂O (1.32 g in terms of CaO), 7.0gCu (NO)₃)₂·3H₂O (2.38 g in terms of CuO), 5.2g of NaNO₃(with Na)₂O is 1.90g) was added to the mixture to prepare a mixed aqueous solution, and 30.0g of carbon powder (33%), 34g of the above binder (37.5%) and 20g (22%) of a-type molecular sieve were added thereto, followed by stirring to sufficiently impregnate the salt in the mixed aqueous solution into the carbon powder. The carbon powder has the following properties: the average pore diameter is 7.8nm, the specific surface area is 255m²/g。

And (3) after filtering, drying the sample in a drying oven at 120 ℃ for 4h, and then stabilizing the sample in a tube furnace at 550 ℃ under the nitrogen atmosphere for 4h to obtain a finished dechlorinating agent D.

Example 5

Fe (NO) with a mass of 3.6g₃)₃·9H₂O (in Fe)₂O₃Calculated as 0.70g) (auxiliary agent 5.2%) and 3.5g of Ca (NO)₃)₂·4H₂O (0.84 g in terms of CaO), 2.8g of KNO₃(with K)₂1.30g in terms of O), 5.0g of Cu (NO)₃)₂·3H₂O (1.70 g calculated as CuO) was added to an aqueous solution, 15.6g of carbon powder (17.7%) by mass, 48g of the above binder (54.5%) and 20g of 13X-type molecular sieve (22.7%) by mass were added thereto, and the mixture was stirred to sufficiently impregnate the salt in the carbon powder. The carbon powder has the following properties: the average pore diameter is 6.6nm, the specific surface area is 268m²/g。

And (3) after filtering, drying the sample in a drying oven at 90 ℃ for 5h, and then stabilizing the sample in a tubular furnace at 600 ℃ under the nitrogen atmosphere for 2h to obtain a finished dechlorinating agent E.

Example 6

Fe (NO) with a mass of 3.6g₃)₃·9H₂O (in Fe)₂O₃0.70g) (5.2%) of NaNO, 4.5g₃(with Na)₂1.64g in terms of O), 6.0gCu (NO)₃)₂·3H₂O (2.04 g in terms of CuO), and 3.5g of Mg (NO)₃)₂·6H₂O (0.55 g in terms of MgO) was added to a mixed aqueous solution, 22.0g of carbon powder (23.4%), 43g (45.8%) of the above binder and 24g of NaY molecular sieve (25.6%) were added, and the mixture was stirred to sufficiently impregnate the carbon powder with the salts. The carbon powder has the following properties: the average pore diameter is 6nm, and the specific surface area is 270m²/g。

And (3) after filtering, drying the sample in a drying oven at 85 ℃ for 5h, and then stabilizing the sample in a tubular furnace at 450 ℃ under the nitrogen atmosphere for 5h to obtain a finished dechlorinating agent F.

Example 7

Fe (NO) with a mass of 3.6g₃)₃·9H₂O (in Fe)₂O₃0.70g) (10.7%) of NaNO, 4.5g₃(with Na)₂1.64g in terms of O), 4.5g of KNO₃(with K)₂2.09g in terms of O) and 6.0g of Cu (NO)₃)₂·3H₂O (2.04 g in terms of CuO) was added to a mixed aqueous solution, and 6.0g (10%) of carbon powder, 30g of the above binder (50%) and 18g (30%) of A-type molecular sieve were added and stirred to sufficiently impregnate the salt in the mixed aqueous solution into the carbon powder. The carbon powder has the following properties: the average pore diameter is 5.5nm, the specific surface area is 280m²/g。

And after filtration, drying the sample in a drying oven at 95 ℃ for 4h, and then roasting the sample in a tube furnace at 650 ℃ under a nitrogen atmosphere for 1h to obtain a finished dechlorinating agent G.

Example 8

SB powder (30 g) and silica polymer particles were added to a nitric acid solution (1 mol/L) and a volume of 90mL, and the mixture was stirred at room temperature for 50 min.

Carbon powder with a mass of 15.0g was added to Mg (NO) with a mass of 7.5g₃)₂·9H₂O (1.18 g in terms of MgO), 2.3g of Ba (NO)₃)₂(1.35 g in terms of BaO), 6.5g of Cu (NO)₃)₂·3H₂O (2.21 g in terms of CuO) was added to 30ml of an aqueous solution, and the mixture was thoroughly immersed with stirring. The carbon powder has the following properties: the average pore diameter is 4.3nm, and the specific surface area is 300m²/g。

After removing the redundant liquid, adding the carbon powder mixture and 15gX type molecular sieve into 30g nitric acid solution and the mixture of SB powder and macromolecular silicon dioxide particles, and stirring and mixing. Kneading and molding the pretreated mixture in a kneader, drying the sample in a drying oven at 120 ℃ for 3H, and then stabilizing the sample in a tubular furnace at 350 ℃ for 6H under the nitrogen atmosphere to obtain a finished dechlorinating agent H.

Example 9

This example shows the results of a test of the ability of dechlorinating agents A-H to remove HCl from reformate. The reformed oil with the chlorine content of 5 mug/L and the water content of 20 mug/L is processed at the temperature of 30-80 ℃, the pressure of 0.1-3MPa and the airspeed of 2-10h^-1Filling a dechlorinating agent under the condition of (1) to carry out a liquid-phase dynamic dechlorination experiment, measuring the chlorine content in the reformed oil flowing out of the dechlorinating tank, and when the chlorine content is more than 0.5 mu g/L, judging the reformed oil to be penetrated, and analyzing the penetrated chlorine capacity of the dechlorinating agent. The penetrated sample was taken out of the dechlorinating apparatus and subjected to chlorine capacity measurement, and the results are shown in table 1.

The measuring method and the calculation formula of the chlorine capacity are as follows:

the mass content of chlorine in the dechlorinating agent after penetration/the total mass of the dechlorinating agent after penetration is 100%.

Table 1: chlorine capacity of sample

As can be seen from table 1 above: the dechlorinating agents A-H all have good chlorine capacity. Under the same conditions, the pressure is from 0.1 to 3MPa, the temperature is from 30 to 80 ℃, the chlorine capacity of the dechlorinating agent is not changed greatly, and the influence of the pressure and the temperature on dechlorination is small; the space velocity is in the range of 2-10, when the space velocity is more than 7, the chlorine capacity is quickly reduced to 27.3% from 30.8% when the chlorine capacity is 6, the chlorine capacity is obviously reduced, and the better space velocity range is 3-6; the high-diameter ratio is in a range of 2: 1-8: 1, the chlorine content is increased along with the increase of the high-diameter ratio, when the high-diameter ratio is 2, the chlorine content is 25.1%, when the high-diameter ratio is 3, the chlorine content is 31.3%, the increase is high, when the high-diameter ratio is increased to 8, the chlorine content is 32.8%, and the increase is not obvious any more. The higher the high-diameter ratio, the better the high-diameter ratio, the higher the high-diameter ratio is, and the larger the pressure drop of a bed layer is, so that the more preferable high-diameter ratio is between 3:1 and 5: 1.

Comparative example 1

Reference to CN1088388C example 1, by weight percent CaCO₃35％、ZnCO₃20 percent and 20 percent of kaolin, mixing the three substances together, and then adding 25 percent of Na into the mixed sample₂CO₃And extruding the mixture into strips with the diameter of 0.45-0.9mm after uniform mixing, and drying and roasting the strips for 1 hour to obtain dechlorinating agent samples.

Comparative example 2

Referring to CN103127903A example 2, 25g of ferrous sulfate, 40g of calcium oxide and 15g of active attapulgite clay are weighed and mixed, and then kneaded for 45 min; adding 35g of silica sol into the uniform dry materials, wet-mixing the materials for 30min until the materials are mixed and ground into paste, putting the paste on a small-sized bar extruding machine, and extruding phi 4 bars; the above-mentioned strands were dried at 180 ℃ for 2 hours to prepare a sample of dechlorinating agent.

Comparative example 3

The procedure of example 8 was followed, wherein the stabilization treatment was changed to a conventional calcination treatment, i.e., calcination at 400 ℃ for 3 hours, to obtain a final dechlorinating agent.

Sample H and the samples obtained in comparative examples 1, 2 and 3 were used under the same conditions for reformate having a water content of 20. mu.g/L and a chlorine content of 5. mu.g/L and for chlorine contentThe reformate with an amount of 5. mu.g/L and a water content of 0.5. mu.g/L was subjected to a dechlorination test. The temperature is selected to be 30 ℃, the high aspect ratio is 4:1, and the liquid airspeed is 4h^-1The chlorine capacity data obtained at a pressure of 3MPa are shown in Table 2.

TABLE 2 dechlorinating agent chlorine capacity as a function of water content for example 8 and comparative examples 1-3

As can be seen from Table 2, the higher the water content in the oil, the smaller the chlorine capacity of the dechlorinating agent; an increase in the trace water content from 0.5 to 25 μ g/L compared to the other dechlorinations reduced the chlorine capacity of the dechlorination agent of example 8 from 35.7 to 31.8 percent by about 4 percentage points, while the chlorine capacity of the comparative dechlorination agent was reduced by more than 10 percentage points, indicating that the optimized dechlorination agent of the present invention has good water resistance.

From the above description, it can be seen that the above-described embodiments of the present invention achieve the following technical effects: the liquid-phase dechlorinating agent has the advantages of low raw material cost, simple preparation method, long service life, high mechanical strength, stable components under the liquid-phase dechlorinating condition, difficult loss, certain desulfurization and denitrification effects, and contribution to the subsequent treatment process of dechlorinated materials.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A liquid phase dechlorination agent, wherein the liquid phase dechlorination agent comprises:

the active component is selected from at least one of an A-type molecular sieve, a 13X molecular sieve and a NaY molecular sieve, and the weight content of the active component in the liquid-phase dechlorinating agent is 20-40%;

the auxiliary agent component is selected from at least three of copper oxide, sodium oxide, potassium oxide, barium oxide, calcium oxide, magnesium oxide, zinc oxide and iron oxide, and the weight content of the auxiliary agent component in the liquid-phase dechlorinating agent is 3-10%;

the carrier is used for loading the active component and the auxiliary component, the carrier is carbon powder, and the weight content of the carbon powder in the liquid-phase dechlorinating agent is 10-33%; and

the balance of binder.

2. The liquid-phase dechlorination agent according to claim 1, wherein the binder is a silica sol and/or an aluminum sol; preferably, the weight content of the binder in the liquid-phase dechlorinating agent is 30-55%.

3. The liquid-phase dechlorination agent according to claim 1, wherein the carbon powder has an average pore size of 50nm or less; preferably, the average pore diameter of the carbon powder is 4-15 nm, and more preferably, the specific surface area of the carbon powder is 200-300 m²/g。

4. The process for the preparation of a liquid-phase dechlorination agent according to any one of claims 1 to 3, characterized in that the process comprises:

dipping a solution prepared from a precursor of the auxiliary agent component on carbon powder to obtain a first mixture;

drying the first mixture, and mixing the dried first mixture with an active component and a binder to obtain a second mixture;

extruding the second mixture to form a dechlorinating agent precursor;

roasting the dechlorinating agent precursor to obtain the liquid-phase dechlorinating agent;

the auxiliary component is at least one selected from copper oxide, zinc oxide and iron oxide, and the active component is at least one selected from A-type molecular sieve, 13X molecular sieve and NaY molecular sieve.

5. The method of claim 4, wherein the precursor of the adjuvant component is a soluble salt, preferably a soluble nitrate or a soluble acetate.

6. The method of claim 4, wherein the step of calcining the dechlorination agent precursor to obtain the liquid-phase dechlorination agent comprises:

drying the dechlorination agent precursor to obtain a dried precursor;

and roasting the dried precursor to obtain the liquid-phase dechlorinating agent.

7. The method according to claim 6, wherein the dechlorination agent precursor is dried at 80-120 ℃ to obtain the dried precursor, preferably for 3-5 h.

8. The method according to claim 6, wherein the dried precursor is calcined under a nitrogen atmosphere to obtain the liquid-phase dechlorinating agent; preferably, the roasting temperature is 350-650 ℃, and the roasting time is 1-6 h.

9. The preparation method of claim 8, wherein the roasting temperature is 450-600 ℃, and the roasting time is 3-5 h.

10. Use of a liquid phase dechlorination agent according to any one of claims 1 to 3 in the dechlorination of reformed oil.

11. Use according to claim 10, wherein the dechlorination process is carried out under conditions in which the reformate is in the liquid phase, preferably the reformate is subjected to the dechlorination process directly without dehydration.

12. The use according to claim 10, wherein the dechlorination treatment is carried out at a temperature of 30 to 80 ℃ and a mass of airThe speed is 2-10h^-1Preferably 3 to 6 hours^-1；

Preferably, the dechlorination treatment is carried out under the pressure of 0.1-3 MPa; the height-diameter ratio of the reactor is 2-8: 1, preferably 3-5: 1.