Method for removing thiophene by lanthanum-manganese bimetallic oxide-based adsorbent

Abstract

The invention relates to the technical field of thiophene adsorption and removal, in particular to a method for removing thiophene by using a lanthanum-manganese bimetallic oxide-based adsorbent, which is characterized in that the lanthanum-manganese bimetallic oxide-based adsorbent is used for removing thiophene; according to the specific preparation method, the La2O3 / MnOx / CMS adsorbent shows higher thiophene adsorption and removal efficiency due to the fact that the synergistic effect of La2O3 and MnOx enhances the active sites of the adsorbent, the adsorption capacity and reaction activity to thiophene are improved, the adsorbent is prepared through calcination at high temperature, the thermal stability and mechanical stability of the adsorbent are improved, and the adsorbent can be applied to the field of adsorption and removal of thiophene. According to the present invention, by using the porous structure, the performance can be maintained for a long time in the industrial application, the replacement frequency and the maintenance cost are reduced, the porous structure is optimized, the specific surface area is high, and more adsorption sites are provided for thiophene molecules, such that the removal efficiency is improved, the relatively cheap raw materials and the simple preparation steps are adopted, and the method is suitable for industrial production. Use of harmful solvents and high-temperature treatment are avoided, good regeneration performance is achieved, and the frequency of replacing the adsorbent is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of thiophene adsorption and removal, in particular to a method for removing thiophene with a lanthanum-manganese bimetallic oxide-based adsorbent. Background Art

[0002] Thiophene removal is mainly achieved through the use of adsorbents. The adsorbents can adsorb thiophene molecules through their porous surface structure and chemical properties. The adsorption method has mild operating conditions and does not require extreme conditions such as high temperature or high pressure, which helps to reduce energy consumption and equipment costs. In addition, the adsorbent can be regenerated by heating or changing temperature, pressure and other conditions to achieve recycling.

[0003] However, existing adsorbents on the market have the following problems: (1) They are insufficient in activity and selectivity and cannot efficiently catalyze the adsorption and removal of thiophene. This may be due to the weak interaction between the active component and the carrier, or because the surface structure and electronic properties of the adsorbent have not been optimized for the specific adsorption characteristics of thiophene. (2) Some adsorbents may exhibit poor thermal and mechanical stability under high-temperature operating conditions, resulting in rapid deactivation of the adsorbent. This may be related to the lattice structure and chemical composition of the adsorbent material, and the failure to form sufficient thermal stability during the preparation process. (3) The use of expensive metals or complex preparation processes leads to high costs, which limits their economic feasibility in industrial-scale applications. (4) Some adsorbents may exhibit poor adaptability in actual industrial environments, such as decreased activity in the presence of water vapor or other impurities. This may be because the surface active sites of the adsorbent are sensitive to environmental changes and the complex industrial conditions were not taken into account during the design. (5) They are difficult to regenerate and recycle, resulting in short service life and waste disposal problems. This may be related to the physical structure and chemical stability of the adsorbent and the failure to consider the needs of long-term use and recycling during the preparation process.

[0004] Therefore, in view of the problems that the above-mentioned adsorbents cannot efficiently catalyze the adsorption and removal of thiophene and the complicated adsorbent preparation process, a method for removing thiophene using a lanthanum manganese bimetallic oxide-based adsorbent can be designed. Summary of the invention

[0005] In order to overcome the problem that the adsorbent cannot efficiently catalyze the adsorption and removal of thiophene and the adsorbent preparation process is complicated.

[0006] The technical solution of the present invention is: a method for removing thiophene by using a lanthanum manganese bimetallic oxide-based adsorbent, wherein the method utilizes the lanthanum manganese bimetallic oxide-based adsorbent to remove thiophene.

[0007] Preferably, the preparation steps of the lanthanum manganese bimetallic oxide-based adsorbent are as follows:

[0008] Step 1: dissolving manganese nitrate tetrahydrate in deionized water until a homogeneous mixture is obtained, a metal salt solution 1;

[0009] Step 2: Immerse the carbon molecular sieve in a metal salt solution 1, age it at 70°C for 12 hours, and then calcine it in air at 300°C for 3 hours to obtain MnO x / CMS;

[0010] Step 3: dissolving lanthanum nitrate in deionized water to obtain a homogeneous mixture, metal salt solution 2;

[0011] Step 4: MnO x / CMS was immersed in metal salt solution 2, aged at 80°C for 24 hours, and then calcined in air at 300°C for 3 hours to obtain La 2 O 3 / MnO x / CMS.

[0012] Preferably, in step 1, the ratio of manganese nitrate tetrahydrate to deionized water is 5 g:30 ml.

[0013] Preferably, the amount of carbon molecular sieve used in step 2 is 20 g.

[0014] Preferably, the ratio of lanthanum nitrate to deionized water in step three is 5.752 g:40 ml.

[0015] As a preferred embodiment, in step 4, MnO x / The dosage of CMS is 20g.

[0016] The beneficial effects of the present invention are as follows: through a specific preparation method, La 2 O 3 / MnO x / CMS adsorbent exhibits higher thiophene adsorption and removal efficiency, which is due to the La 2 O 3The synergistic effect of MnOx and MnOx enhances the active sites of the adsorbent, thereby improving the adsorption capacity and reaction activity of thiophene. The adsorbent is prepared by calcination at high temperature, thereby improving its thermal stability and mechanical stability, enabling it to maintain performance for a long time in industrial applications, reducing replacement frequency and maintenance costs. The adsorbent of the present invention has an optimized pore structure and a high specific surface area, which provides more adsorption sites for thiophene molecules, thereby improving the removal efficiency. Relatively cheap raw materials and simple preparation steps are used to reduce production costs while maintaining high efficiency and improving market competitiveness. The preparation method of the present invention avoids the use of harmful solvents and high-temperature treatment, reduces the impact on the environment, and meets the requirements of green chemistry and sustainable development. Using carbon molecular sieves as carriers, the present invention improves the utilization rate of solid waste, promotes the recycling of resources, has good regeneration performance, can restore its activity through a simple regeneration process, prolongs its service life, and reduces waste generation. Due to the high efficiency and long life of the adsorbent, users can reduce the frequency of replacing the adsorbent, reduce long-term operating costs, and improve economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a SEM image of the lanthanum manganese bimetallic oxide-based adsorbent of the present invention;

[0018] Figure 2 Shown is a graph of the specific surface area of ​​the lanthanum manganese bimetallic oxide-based adsorbent of the present invention;

[0019] Figure 3 Shown is a graph of the desulfurization efficiency of the lanthanum manganese bimetallic oxide-based adsorbent of the present invention. DETAILED DESCRIPTION

[0020] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0021] The present invention provides an embodiment: a method for removing thiophene using a lanthanum manganese bimetallic oxide-based adsorbent. The method uses the lanthanum manganese bimetallic oxide-based adsorbent to remove thiophene.

[0022] Preferably, the preparation steps of the lanthanum manganese bimetallic oxide-based adsorbent are as follows:

[0023] Step 1: dissolving manganese nitrate tetrahydrate in deionized water until a homogeneous mixture is obtained, a metal salt solution 1;

[0024] Step 2: Immerse the carbon molecular sieve in a metal salt solution 1, age it at 70°C for 12 hours, and then calcine it in air at 300°C for 3 hours to obtain MnO x / CMS;

[0025] Step 3: dissolving lanthanum nitrate in deionized water to obtain a homogeneous mixture, metal salt solution 2;

[0026] Step 4: MnO x / CMS was immersed in metal salt solution 2, aged at 80°C for 24 hours, and then calcined in air at 300°C for 3 hours to obtain La 2 O 3 / MnO x / CMS.

[0027] Preferably, in step 1, the ratio of manganese nitrate tetrahydrate to deionized water is 5 g:30 ml.

[0028] Preferably, the amount of carbon molecular sieve used in step 2 is 20 g.

[0029] Preferably, the ratio of lanthanum nitrate to deionized water in step three is 5.752 g:40 ml.

[0030] As a preferred embodiment, in step 4, MnO x / The dosage of CMS is 20g.

[0031] Example 1

[0032] The steps for preparing the lanthanum manganese bimetallic oxide based adsorbent are as follows:

[0033] Step 1: Dissolve 5 g of manganese nitrate tetrahydrate in 30 ml of deionized water until a homogeneous mixture is obtained, metal salt solution 1;

[0034] Step 2: Immerse the carbon molecular sieve in a metal salt solution 1, age it at 70°C for 12 hours, and then calcine it in air at 300°C for 3 hours to obtain MnO x / CMS;

[0035] Step 3: dissolve 5.752 g of lanthanum nitrate in 40 ml of deionized water to obtain a homogeneous mixture, metal salt solution 2;

[0036] Step 4: 20gMnO x / CMS was immersed in metal salt solution 2, aged at 80°C for 24 hours, and then calcined in air at 300°C for 3 hours to obtain La 2 O 3 / MnO x / CMS.

[0037] Experimental example

[0038] (1)La 2 O 3 / MnO x Surface structure and morphology of / CMS

[0039] Take La prepared in Example 1 2 O 3 / MnO x / CMS, scanning electron microscope uses the interaction of the sample surface to generate secondary electrons, backscattered electrons and other signals, and obtains the surface morphology, composition and other information of the sample by detecting these signals. Its SEM image is as follows Figure 1 .

[0040] (2)La 2 O 3 / MnO x / Specific surface area of ​​CMS

[0041] The La 2 O 3 / MnO x / CMS specific surface area diagram, such as Figure 2 .

[0042] (3) Thiophene adsorption and removal test

[0043] Take CMS, MnO respectively x / CMS, La 2 O 3 / CMS and La prepared in Example 1 2 O 3 / MnO x / CMS, conduct thiophene adsorption removal test, desulfurization efficiency Figure 3 .

[0044] Through the above steps, the preparation method avoids the use of harmful organic solvents and high-temperature treatment, reduces the impact on the environment, and meets the requirements of green chemistry and sustainable development; by using carbon molecular sieves as carriers, the method helps to improve the utilization rate of solid waste and promotes the recycling of resources; mild aging and calcination conditions reduce energy consumption, help reduce the carbon footprint in the production process, and achieve a more sustainable production process; the use of relatively cheap raw materials (such as lanthanum nitrate and manganese nitrate tetrahydrate) and simple preparation steps (such as dissolution, impregnation and calcination) help to reduce the production cost of the adsorbent and improve its market competitiveness; through the step-by-step impregnation and calcination method, the La 2 O 3 and MnO x The distribution and interaction of adsorbents on CMS are crucial to improving the selectivity and activity of the adsorbents to solve the problems of the adsorbents' inability to efficiently catalyze the adsorption and removal of thiophene and the complex adsorbent preparation process.

[0045] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the spirit of the present invention.

Claims

1. A method for removing thiophene using a lanthanum manganese bimetallic oxide-based adsorbent, characterized in that: The method utilizes lanthanum manganese bimetallic oxide-based adsorbent to remove thiophene.

2. The method for removing thiophene using a lanthanum-manganese bimetallic oxide-based adsorbent according to claim 1, characterized in that: The preparation steps of lanthanum manganese bimetallic oxide based adsorbent are as follows: Step 1: dissolving manganese nitrate tetrahydrate in deionized water until a homogeneous mixture is obtained, a metal salt solution 1; Step 2: Immerse the carbon molecular sieve in a metal salt solution 1, age it at 70°C for 12 hours, and then calcine it in air at 300°C for 3 hours to obtain MnO x / CMS; Step 3: dissolving lanthanum nitrate in deionized water to obtain a homogeneous mixture, metal salt solution 2; Step 4: MnO x / CMS was immersed in metal salt solution 2, aged at 80 °C for 24 h, and then calcined in air at 300 °C for 3 h to obtain La2O3 / MnO x / CMS.

3. The method for removing thiophene using a lanthanum-manganese bimetallic oxide-based adsorbent according to claim 2, characterized in that: In step 1, the usage ratio of manganese nitrate tetrahydrate and deionized water is 5g:30ml.

4. The method for removing thiophene using a lanthanum-manganese bimetallic oxide-based adsorbent according to claim 2, characterized in that: The amount of carbon molecular sieve used in step 2 is 20 g.

5. The method for removing thiophene using a lanthanum-manganese bimetallic oxide-based adsorbent according to claim 2, characterized in that: In step 3, the usage ratio of lanthanum nitrate and deionized water is 5.752 g:40 ml.

6. The method for removing thiophene using a lanthanum-manganese bimetallic oxide-based adsorbent according to claim 2, characterized in that: Step 4: MnO x / The dosage of CMS is 20g.

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