Low-temperature liquid-phase dechlorinating agent based on blast furnace slag and preparation method of low-temperature liquid-phase dechlorinating agent

Abstract

The invention discloses a low-temperature liquid-phase dechlorinating agent based on blast furnace slag and a preparation method of the low-temperature liquid-phase dechlorinating agent, and belongs to the technical field of dechlorinating. Wherein the raw materials of the dechlorinating agent comprise, by mass, 40%-60% of blast furnace slag, 40%-60% of molecular sieves and 5%-10% of auxiliaries. The selected molecular sieve is X-type or Y-type. The obtained dechlorinating agent is high in chloride adsorption capacity and good in dechlorinating effect under the low-temperature condition, the removal rate of organic chloride in a liquid phase can be effectively increased, the waste blast furnace slag is prepared through organic acid treatment, molecular sieve filtrate modification, mixed extrusion molding and secondary dipping activation, the cost is reduced, industrial production is facilitated, and the method is suitable for industrial production. And the pollution of blast furnace slag to the environment is also reduced.

Description

Technical Field

[0001] This invention belongs to the technical field of oil dechlorination agents. More specifically, it relates to a low-temperature liquid-phase dechlorination agent based on blast furnace slag and its preparation method. Background Technology

[0002] There are two forms of chlorides in petroleum products: organic chlorides and inorganic chlorides. During petroleum processing, most inorganic chlorides can be removed through electro-desalting and dehydration. However, a small portion is difficult to remove and hydrolyzes during subsequent distillation, producing corrosive hydrogen chloride, which can exacerbate pipeline and equipment corrosion, cause catalyst poisoning, lead to pipeline blockage, and jeopardize normal equipment operation. Organic chlorides in crude oil mainly exist in the form of chlorinated alkanes, which are insoluble in water and therefore cannot be removed by conventional desalting and dehydration methods.

[0003] Blast furnace slag is a byproduct of ironmaking, producing approximately 300 to 350 kilograms of blast furnace slag per ton of pig iron. With the continuous progress and development of the metallurgical industry, blast furnace slag production remains high. Currently, my country's resource utilization of blast furnace slag is somewhat insufficient, resulting in a very high accumulation of blast furnace slag in the country, with current stockpiles exceeding 1 billion tons.

[0004] Currently, several dechlorinating agents have been developed both domestically and internationally for pre-hydrogenation of oil products, ammonia produced as a byproduct of reforming, and regenerated reformate. Dechlorination of reformate has also received attention and research. The traditional process for oil dechlorination involves converting organic chlorine into inorganic chlorine through hydrogenation, followed by the removal of the inorganic chlorine. Therefore, research on oil dechlorination largely focuses on the removal of inorganic chlorine, with less research on the direct adsorption and removal of organic chlorine from oil products. For processes where hydrogenation is unnecessary, adding a hydrogenation unit solely for dechlorination is undoubtedly uneconomical. This is particularly true for small and medium-sized refineries without hydrogenation capabilities.

[0005] US5928500 describes a method for removing trace amounts of organochlorides from hydrocarbon components. This method uses porous silica with a high specific surface area as a carrier and metals or metal oxides of Ni, Co, or iron and mixtures thereof as adsorbents to convert organochlorides into metal chlorides, thereby removing them.

[0006] CN104437342A discloses a low-temperature liquid-phase molecular sieve dechlorinating agent suitable for removing hydrogen chloride from reforming oil. The active components are oxides of alkali metals and alkaline earth metals, and the auxiliary components are copper oxide, iron oxide, or zinc oxide. This dechlorinating agent uses a carbonaceous carrier, has a complex preparation process, and is costly. It also poses a risk of combustion and explosion during high-temperature calcination, and the active components are easily lost. Summary of the Invention

[0007] To address the issues of complex preparation processes, high costs, and low strength in existing technologies, this invention provides a low-temperature liquid-phase dechlorinating agent based on blast furnace slag and its preparation method. The dechlorinating agent prepared by this invention possesses high radial crushing resistance and good organic chlorine removal rate.

[0008] Therefore, the present invention provides a liquid-phase dechlorination agent, wherein the raw materials of the dechlorination agent, by mass percentage, include 40%~60% blast furnace slag, 40%~60% molecular sieve, and 5%~10% additives; Furthermore, the preparation method includes: (1) Grind the water-quenched blast furnace slag into fine powder, add organic acid, stir at 70°C for 2 hours, filter to obtain filtrate A and precipitate B, and dry precipitate B for later use. (2) Add molecular sieve to solution A, stir at 70°C for 4 hours, and filter to obtain mixture C; (3) After mixing B, C and the corresponding mass of additives, the mixture is extruded into strips, dried and calcined, and then added to solution A for soaking for 4 hours. After filtration, drying and calcination, the dechlorinating agent is obtained.

[0009] Furthermore, the blast furnace slag used is water-quenched, and its main components, by mass percentage, are 40.7%-44.6% CaO, 30.2%-35.2% SiO2, 10.1%-14.3% Al2O3, 7.4%-9.8% MgO, and 3.5%-4.2% Fe2O3. 3； Furthermore, the molecular sieve is an X-type or Y-type molecular sieve; Furthermore, the additive is boehmite or aluminum sol; Furthermore, the acid solution used in the preparation method is a 20% acetic acid solution or a 20% citric acid solution; Furthermore, the drying temperature is 105-120℃ for 2-6 hours, and the calcination temperature is 400-600℃ for 3-8 hours. Furthermore, the liquid-phase dechlorination agent has a strength of 100-140 N / cm and a specific surface area of ​​560-650 m². 2 / g, with a pore volume of 0.35-0.42ml / g.

[0010] Furthermore, the dechlorinating agent prepared by this institute is used to adsorb and remove organic chlorine from reformed oil, with an operating temperature of 20-90℃ and an operating pressure of 0.5-3 MPa.

[0011] The beneficial effects of this invention are: 1. After water quenching, the main metallic components of blast furnace slag are CaO, SiO2, Al2O3, MgO, and Fe2O3. After organic acid treatment, the filter residue is amorphous silica with a huge specific surface area and abundant pore structure, which inherently possesses physical adsorption properties. Impregnating it with composite metal oxides allows for strong chemical adsorption between the oxygen vacancy defects generated by the active components and the chlorine atoms in the organic chlorine.

[0012] 2. Compared with strong inorganic acids such as hydrochloric acid and nitric acid, organic acids are relatively weaker. When molecular sieves are modified with organic acids, the reaction is less violent, reducing the risk of crystal structure damage or even collapse due to excessive removal of framework elements. This can better maintain the crystallinity and framework integrity of the molecular sieve. Metal ion modification can improve the surface chemical properties of the molecular sieve, especially the surface acid properties, and enhance the dechlorination ability of the molecular sieve.

[0013] 3. Amorphous silica and modified molecular sieves are extruded into strips and then impregnated with a metal acid solution. The filtrate is rich in metal ions such as calcium, magnesium, and iron, which is equivalent to an organic acid salt solution. After impregnation, these salts decompose and form highly dispersed alkaline metal oxide active sites on the surface or in the pores of the molecular sieve. These sites have a strong chemical adsorption capacity for chlorine, which can not only improve the strength of the dechlorinating agent, but also improve the removal rate. Detailed Implementation

[0014] The following embodiments are provided to better understand the present invention and are not limited to the preferred embodiments described. They do not constitute a limitation on the content and scope of protection of the present invention. Any product that is the same as or similar to the present invention, derived by any person under the guidance of the present invention or by combining the features of the present invention with other prior art, falls within the protection scope of the present invention. Example 1

[0015] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High SiO2 Al2O3 MgO Fe2O 44.6% 30.2% 14.3% 7.4% 3.5% Take 40 parts of the above-mentioned blast furnace slag fine powder, place it in 20% citric acid, stir at 70℃ for 2 hours, filter to obtain filtrate A and precipitate B, wherein the mass ratio of blast furnace slag fine powder to acid solution is 1:5; Take 60 portions of 13X molecular sieve and add them to filtrate A. Stir at 70°C for 4 hours. Filter the mixture to obtain mixture C. B, C and 10 parts of pseudoboehmite were mixed and extruded into strips. After drying at 120°C for 2 hours and calcining at 500°C for 5 hours, a dechlorination agent precursor was obtained. The precursor was then immersed in filtrate A for 4 hours, dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain the dechlorination agent. Example 2

[0016] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High SiO2 Al2O3 MgO Fe2O 44.6% 30.2% 14.3% 7.4% 3.5% Take 60 parts of the above-mentioned blast furnace slag fine powder, place it in 20% citric acid, stir at 70℃ for 2 hours, filter to obtain filtrate A and precipitate B, wherein the mass ratio of blast furnace slag fine powder to acid solution is 1:4; Take 40 portions of 13X molecular sieve and add them to filtrate A. Stir at 70°C for 4 hours and filter to obtain mixture C. After mixing B, C and 10 parts of aluminum sol, the mixture was extruded into strips, dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain a dechlorination agent precursor. The precursor was then immersed in filtrate A for 4 hours, dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain the dechlorination agent. Comparative Example 1

[0017] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High SiO2 <![CDATA[Al2O3]]> MgO <![CDATA[Fe2O]]> 44.6% 30.2% 14.3% 7.4% 3.5% Take 60 parts of 13X molecular sieve, 40 parts of blast furnace slag and 10 parts of pseudoboehmite, mix them and extrude them into strips, dry them at 120℃ for 2 hours and calcine them at 500℃ for 5 hours to obtain a dechlorinating agent. Comparative Example 2

[0018] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High <![CDATA[SiO2]]> <![CDATA[Al2O3]]> MgO <![CDATA[Fe2O]]> 44.6% 30.2% 14.3% 7.4% 3.5% Take 40 parts of the above-mentioned blast furnace slag fine powder, place it in 20% citric acid, stir at 70℃ for 2 hours, filter to obtain filtrate A and precipitate B, wherein the mass ratio of blast furnace slag fine powder to acid solution is 1:5; Take 60 portions of 13X molecular sieve and add them to filtrate A. Stir at 70°C for 4 hours. Filter the mixture to obtain mixture C. B, C and 10 parts of pseudoboehmite were mixed and extruded into strips, which were then dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain a dechlorinating agent. Comparative Example 3

[0019] Take 60 parts of 13X molecular sieve and 40 parts of pseudoboehmite, mix them, extrude them into strips, dry them at 120℃ for 2 hours, and then calcine them at 500℃ for 5 hours to obtain a dechlorinating agent. Example 3

[0020] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High <![CDATA[SiO2]]> <![CDATA[Al2O3]]> MgO <![CDATA[Fe2O]]> 40.7% 35.2% 10.1% 9 .8% 4.2% Take 40 portions of the above-mentioned blast furnace slag fine powder, place them in 20% acetic acid, stir at 70°C for 2 hours, filter to obtain filtrate A and precipitate B, wherein the mass ratio of blast furnace slag fine powder to acid solution is 1:5; Take 60 parts of NaY molecular sieve and add them to filtrate A. Stir at 70℃ for 4 hours and filter to obtain mixture C. B, C and 5 parts of pseudoboehmite were mixed and extruded into strips. After drying at 120℃ for 2 hours and calcining at 550℃ for 5 hours, a dechlorination agent precursor was obtained. The precursor was then immersed in filtrate A for 4 hours, dried at 120℃ for 2 hours and calcined at 550℃ for 5 hours to obtain the dechlorination agent. Example 4

[0021] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High <![CDATA[SiO2]]> <![CDATA[Al2O3]]> MgO <![CDATA[Fe2O]]> 40.7% 35.2% 10.1% 9 .8% 4.2% Take 60 parts of the above-mentioned blast furnace slag fine powder, place it in 20% acetic acid, stir at 70°C for 2 hours, filter to obtain filtrate A and precipitate B, wherein the mass ratio of blast furnace slag fine powder to acid solution is 1:4; Take 40 parts of NaY molecular sieve and add them to filtrate A. Stir at 70°C for 4 hours and filter to obtain mixture C. After mixing B, C and 10 parts of aluminum sol, the mixture was extruded into strips, dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain a dechlorination agent precursor. The precursor was then immersed in filtrate A for 4 hours, dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain the dechlorination agent. Comparative Example 4

[0022] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High <![CDATA[SiO2]]> <![CDATA[Al2O3]]> MgO <![CDATA[Fe2O]]> 40.7% 35.2% 10.1% 9 .8% 4.2% Take 60 parts of NaY molecular sieve, 40 parts of blast furnace slag and 5 parts of pseudoboehmite, mix them and extrude them into strips, dry them at 120℃ for 2 hours and calcine them at 500℃ for 5 hours to obtain a dechlorinating agent. Comparative Example 5

[0023] The water-quenched blast furnace slag is ground into a fine powder, the blast furnace slag comprising the following components: High <![CDATA[SiO2]]> <![CDATA[Al2O3]]> MgO <![CDATA[Fe2O]]> 40.7% 35.2% 10.1% 9 .8% 4.2% Take 40 portions of the above-mentioned blast furnace slag fine powder, place them in 20% acetic acid, stir at 70°C for 2 hours, filter to obtain filtrate A and precipitate B, wherein the mass ratio of blast furnace slag fine powder to acid solution is 1:5; Take 60 parts of NaY molecular sieve and add them to filtrate A. Stir at 70℃ for 4 hours and filter to obtain mixture C. B, C and 5 parts of pseudoboehmite were mixed and extruded into strips, which were then dried at 120°C for 2 hours and calcined at 500°C for 5 hours to obtain a dechlorinating agent. Comparative Example 6

[0024] Take 60 parts of NaY molecular sieve and 40 parts of pseudoboehmite, mix them, extrude them into strips, dry them at 120℃ for 2 hours, and then calcine them at 500℃ for 5 hours to obtain a dechlorinating agent.

[0025] The following are the specificity, pore volume, and strength data:

[0026] The dechlorinating agents prepared in each embodiment and comparative example were subjected to performance tests for removing organochlorines. Specifically, oil with a chlorine content of approximately 100 mg / L was subjected to tests at 70°C, 1.5 MPa, and a liquid hourly space velocity of 2 h⁻¹. -1 Under the specified conditions, a liquid-phase dynamic dechlorination experiment was conducted. The outlet chlorine content was determined using a coulometric analyzer. The removal rate was calculated according to the formula: Removal rate = (Inlet chlorine content - Outlet chlorine content) / Inlet chlorine content * 100%. The results are shown in the table below.

[0027] Comparative Examples 1 and 4 show that direct extrusion of molecular sieves with blast furnace slag increases strength but reduces removal rate. Comparative Examples 3 and 6 show that blank molecular sieves exhibit good removal rate initially, but decrease significantly over time, reaching 15% in the later stages. Comparative Examples 2 and 5 show that samples without secondary impregnation have a high removal rate before 6 hours, but their stability weakens slightly in the later stages. Examples 1, 2, 3, and 4 show that after modifying molecular sieves with filtrate, the remaining filtrate can be fully utilized to further modify the dechlorination agent precursor, enhancing its dechlorination stability.

[0028] By selectively activating blast furnace slag with organic acids and pre-modifying molecular sieves with their filtrate, the activated solid components are then combined with the modified molecular sieves, molded, and subjected to secondary impregnation and activation. This process not only improves the strength but also enhances the stability of the dechlorinating agent. The dechlorination rate remains above 85% even after 24 hours of operation, thus achieving high-value-added resource utilization of waste blast furnace slag.

[0029] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A low-temperature liquid-phase dechlorination agent based on blast furnace slag and a method for producing the same, characterized by comprising: The raw material of the dechlorination agent contains 40-60% of blast furnace slag, 40-60% of molecular sieve and 5-10% of auxiliary agent by mass percentage; The preparation method comprises: (1) grinding the blast furnace slag quenched by water into fine powder, adding organic acid, stirring at 70 DEG C for 2h, filtering to obtain filtrate A and precipitate B, drying the precipitate B for standby; (2) adding the molecular sieve into the filtrate A, stirring at 70 DEG C for 4h, filtering to obtain mixture C, and the rest of the filtrate is recorded as filtrate D; (3) mixing B, C and the auxiliary agent, extruding into strips, drying and calcining after shaping, then adding into the filtrate D, soaking for 4h, filtering, drying and calcining to obtain the dechlorination agent.

2. A low temperature liquid phase dechlorination agent based on blast furnace slag according to claim 1, characterized by: The blast furnace slag used in step (1) is quenched by water, and its main components by mass percentage are 40.7-44.6% of CaO, 30.2-35.2% of SiO2, 10.1-14.3% of Al2O3, 7.4-9.8% of MgO and 3.5-4.2% of Fe2O3.

3. A low temperature liquid phase dechlorination agent based on blast furnace slag according to claim 1, and a method for preparing the same, characterized in that: The molecular sieve is X type or Y type molecular sieve.

4. A low temperature liquid phase dechlorination agent based on blast furnace slag according to claim 1, and a method for preparing the same, characterized in that: The auxiliary agent is pseudo-boehmite or aluminum sol.

5. A low temperature liquid phase dechlorination agent based on blast furnace slag according to claim 1, and a method for preparing the same, characterized in that: The drying temperature is 105-120 DEG C, the time is 2-6h, the calcining temperature is 400-600 DEG C, and the time is 3-8h.

6. A low temperature liquid phase dechlorination agent based on blast furnace slag according to claim 1, and a method for preparing the same, characterized in that: The prepared dechlorination agent has a strength of 100-140 N / cm, a specific surface area of 560-650 m 2 / g, and a pore volume of 0.35-0.42 ml / g.

7. A low temperature liquid phase dechlorination agent based on blast furnace slag according to claim 1, and a method for preparing the same, characterized in that: The prepared dechlorination agent is applied to adsorb and remove organic chlorine in reforming oil, the using temperature is 20-90 DEG C, and the using pressure is 0.5-3Mpa.

Images