Adsorbent composition, its manufacturing method and application

Abstract

The present invention relates to an adsorbent composition, its manufacturing method, and its application. The adsorbent composition of the present invention comprises a molecular sieve, hydrated alumina, and alumina. The adsorbent composition of the present invention has considerable adsorption capacity and excellent compressive strength, is easy to regenerate, does not show significant heat release from adsorption, and is particularly suitable for removing polar compounds from low-carbon olefins.

Description

Detailed Description of the Invention

[0001] FIELD OF THE INVENTION The present disclosure relates to adsorption technology. In particular, the present disclosure relates to adsorbent compositions for removing polar compounds from light olefins, as well as methods for their manufacture and application.

[0002] BACKGROUND OF THE INVENTION Low-carbon olefins, such as ethylene, propylene, and butene, are important industrial raw materials. They are widely used in the petrochemical industry. For example, they can be polymerized to produce polyolefins, epoxidized to produce propylene oxide, butylene oxide, etc., or alkylated with aromatic compounds to produce ethylbenzene, cumene, diisopropylbenzene, etc. Industrial low-carbon olefins typically contain polar compounds, such as HO, methanol, ammonia, and HS, as impurities. The presence of such polar compounds can adversely affect the polymerization, epoxidation, and alkylation catalysts used in subsequent processes, potentially affecting their efficiency and lifespan. Therefore, efficient removal of polar compounds is important for protecting catalysts in downstream equipment and maintaining stable operation of the equipment over the long term.

[0003] Adsorption methods are widely used to remove polar compounds due to their advantages of simple operation, low energy consumption, etc. Bentonite, clay, kaolin, molecular sieves, etc. are commonly used as adsorbents. Generally, the adsorbent is placed upstream of the reactor containing the catalyst to remove polar compounds from the low-carbon olefin feedstock, thereby reducing catalyst poisoning.

[0004] CN1461290A discloses a method for removing polar impurities from an aromatic feedstock, comprising contacting an aromatic feedstock containing polar compounds with an adsorbent, the adsorbent comprising a molecular sieve having pores and / or surface cavities with cross-sectional dimensions greater than 5.6 angstroms; and feeding the resulting treated aromatic feedstock to an alkylation reaction unit.

[0005] CN103418164B discloses a method for removing oxygen-containing compounds from hydrocarbon streams by using a porous metal-organic compound as a solid sorbent, the solid sorbent being a porous metal-organic compound of the formula M3(BTC)2(L)3m, where M is at least one transition metal element selected from the group consisting of Cu, Co, Fe, Ni, Zn, and Cr, BTC represents deprotonated pyromellitic acid, L is at least one solvent molecule selected from the group consisting of HO, NH3, CH3OH, DMF, THF, and CH5OH, and m represents the average number of solvent molecules combined with each metal ion, where 0≦m≦1.

[0006] CN107970781A discloses a molecular sieve ceramic membrane material for olefin purification, as well as its manufacturing method and application. In this molecular sieve ceramic membrane material, the particle size of the molecular sieve particles supported on the surface of the ceramic material is 0.1 μm to 3 μm, and the thickness of the molecular sieve layer is 3 μm to 5 μm. During manufacturing, ceramic material pretreatment, molecular sieve seed crystal precoating, and sealed crystallization are sequentially performed to obtain the molecular sieve ceramic membrane material. The molecular sieve ceramic membrane material is used to remove polar oxygen-containing compounds from gaseous olefin streams to levels below 1 ppm.

[0007] However, existing methods for removing polar compounds still have problems, such as low adsorption capacity of the adsorbent, non-regeneration of the adsorbent, large amounts of solid waste, substantial heat release from adsorption, and a tendency to olefin polymerization. Olefins are unsaturated hydrocarbons with strong polarity. Therefore, when using molecular sieves to remove polar compounds from low-carbon olefins, the low-carbon olefins may be adsorbed while the polar compounds are being adsorbed, resulting in a rapid increase in the heat of adsorption, which in turn may result in the polymerization of the low-carbon olefins on the surface of the adsorbent. At the same time, molecular sieves are difficult to desorb after adsorbing polar compounds, resulting in incomplete regeneration. In addition, molecular sieves have limited strength, limiting the flexibility of their application.

[0008] Therefore, there remains a need for further modification of molecular sieves and development of new adsorbent compositions to more effectively remove polar compounds.

[0009] Summary of the Invention To solve one or more of the above problems, the present disclosure provides an adsorbent composition comprising a molecular sieve, hydrated alumina, and alumina. The adsorbent composition according to the present disclosure has considerable adsorption capacity, is easy to regenerate, has excellent compressive strength, and does not release substantial heat of adsorption, making it particularly suitable for removing polar compounds from low-carbon olefins. The present disclosure also relates to a method for producing and applying the adsorbent composition.

[0010] In a first aspect of the present disclosure, there is provided an adsorbent composition for removing polar compounds from low-carbon olefins, comprising a molecular sieve, hydrated alumina, and alumina. Preferably, the adsorbent composition comprises, by weight: a) 10 to 50 parts, preferably 20 to 40 parts, of the molecular sieve; b) 20 to 55 parts, preferably 30 to 45 parts, calculated as alumina, of the hydrated alumina; and c) 5 to 35 parts, preferably 8 to 30 parts, of the alumina. More preferably, the adsorbent composition has a total strong acid content of less than 0.05 mmol / g, preferably 0.01 mmol / g to 0.04 mmol / g.

[0011] In a further aspect of the present disclosure, there is provided a method for producing an adsorbent composition for removing polar compounds from low carbon olefins, comprising the steps of: A step of subjecting the molecular sieve, hydrated alumina and alumina to mixing, shaping, drying and calcining to obtain the adsorbent composition, wherein the calcination is carried out at a temperature of less than 400°C.

[0012] In yet a further aspect of the present disclosure, there is provided the use of the adsorbent composition in removing polar compounds from low carbon olefins, preferably the low carbon olefins include ethylene, propylene, butene, etc., and the polar compounds include HO, methanol, ammonia, HS, COS, etc.

[0013] The adsorbent composition according to the present disclosure includes a combination of molecular sieves, hydrated alumina, and alumina, and the combination can adjust the pore structure, acidity, and polarity of the resulting adsorbent composition. Therefore, the adsorbent composition according to the present disclosure can desorb polar compounds such as ammonia at lower temperatures and is easy to regenerate in situ. Furthermore, the adsorbent composition according to the present disclosure can reduce and avoid local temperature rises during adsorption, thereby reducing and avoiding the risk of undesired olefin polymerization. Furthermore, the adsorbent composition according to the present disclosure has improved compressive strength, thereby providing better long-term stability. Therefore, the adsorbent composition according to the present disclosure has broader application prospects.

[0014] BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings are included to provide a further understanding of the invention, are a part of this specification, and together with the following detailed description of the invention, illustrate the invention but are not intended to limit its scope. FIG. 1 shows the breakthrough curves of the adsorbent composition prepared in Example 1 for the adsorption of NH3 and H2S; Figure 2 shows the NH3-TPD curve of the adsorbent composition prepared in Example 1 after one or more regenerations; FIG. 3 shows the XRD pattern of the adsorbent composition prepared in Example 1.

[0015] Detailed Description of the Invention It should be understood that the endpoints of the ranges and any value disclosed herein are not limited to the exact range or value, but encompass values ​​close to that range or value. For ranges of values, it is possible to combine the endpoints of each range, the endpoints of each range and the individual points, and the individual points to provide one or more new ranges of values, just as if those ranges of values ​​were specifically disclosed herein.

[0016] Other than in the examples, all numerical values ​​of parameters herein should be understood to be modified in all instances by the term "about," regardless of whether "about" actually appears before the numerical value.

[0017] As used herein, the term "low carbon olefin" refers to olefins having 2 to 4 carbon atoms, including ethylene, propylene, butene, and the like.

[0018] As used herein, the term "acidity" refers to the amount of active sites in an adsorbent used to adsorb alkaline polar compounds. Generally, adsorbents exhibit two NH3 desorption peaks, corresponding to the various acidic sites of the adsorbent. Therefore, acidity can be measured through the NH3-TPD curve of the adsorbent. Specifically, the distribution of different acidic sites in the adsorbent can be obtained by fitting the areas of each desorption peak. Herein, active sites corresponding to temperatures below 300°C in the NH3-TPD curve of the adsorbent are considered weak acids, and active sites corresponding to temperatures above 300°C are considered strong acids. By fitting the desorption curve to the obtained NH3-TPD profile of the adsorbent, the desorption peak area of ​​the corresponding strong or weak acid can be obtained, and the ratio of weak or strong acid to total acid can be calculated. The total amount of acid can be measured by weighing using a microbalance. The total amount of strong or weak acid can be calculated based on the total amount of acid and the above ratio.

[0019] As used herein, the term "molecular sieve" is interchangeable with "zeolite" and "zeolitic molecular sieve."

[0020] In one aspect, the present disclosure relates to an adsorbent composition for removing polar compounds from low carbon olefins, the adsorbent composition comprising a molecular sieve, hydrated alumina, and alumina. In one variation, the adsorbent composition comprises, by weight: a) 10 to 50 parts, preferably 20 to 40 parts, of the molecular sieve; b) 20 to 55 parts, preferably 30 to 45 parts, calculated as alumina, of the hydrated alumina; and c) 5 to 35 parts, preferably 8 to 30 parts, of the alumina.

[0021] In one variation, the adsorbent composition has a total amount of strong acids of less than 0.05 mmol / g, preferably between 0.01 mmol / g and 0.04 mmol / g.

[0022] In one variation, the XRD pattern of the adsorbent composition comprises diffraction peaks at 6.03°, 13.47°, 15.32°, 28.01°, 37.96° and 49.28° 2θ, preferably comprises diffraction peaks at 6.03°, 13.47°, 15.32°, 28.01°, 23.16°, 37.96°, 46.34°, 49.28° and 66.8° 2θ, and more preferably comprises diffraction peaks at 2θ as outlined in the table below:

[0023] [Table 1]

[0024] .

[0025] From the XRD pattern of the adsorbent composition, derivative peaks attributable to the molecular sieve, such as diffraction peaks at 2θ of 6.03°, 9.87°, 11.6°, 15.32°, 23.16°, 26.5°, and 30.8°, derivative peaks attributable to hydrated alumina, such as diffraction peaks at 2θ of 13.47°, 28.01°, 37.96°, 49.28°, and 64.7°, and derivative peaks attributable to alumina, such as diffraction peaks at 2θ of 46.34° and 66.8° can be identified.

[0026] Molecular sieves (or zeolites) have a basic framework in which SiO4 and AlO4 tetrahedra are bonded through shared oxygen atoms to form a three-dimensional network. This combination can result in voids and channels of molecular size and uniform pore size. The structure of zeolites confers functions such as molecular sieving, adsorption, ion exchange, and catalysis. In one embodiment, microporous molecular sieves with pore sizes of 2 nm or less are preferred. In one variation, the molecular sieve is one or two selected from the group consisting of X-type molecular sieves and Y-type molecular sieves, preferably one or two selected from the group consisting of 13X and NaY.

[0027] The hydrated alumina may be, for example, pseudoboehmite, boehmite, gibbsite, bayerite, etc., and is preferably pseudoboehmite. The hydrated alumina is commercially available or can be prepared according to techniques known in the art. In one embodiment, the hydrated alumina is 200 ml 2 / g~500m 2 / g, preferably 300m 2 / g~400m 2 / g specific surface area, and 0.2 cm 3 / g~0.5cm 3 / g, preferably 0.3 cm 3 / g~0.4cm 3 / g pore volume. In one variation, the hydrated alumina has a pore size of 2.0 nm to 5.0 nm, preferably 4.0 nm to 5.0 nm. In one variation, the hydrated alumina has a total amount of weak acids of 0.20 mmol / g to 0.50 mmol / g.

[0028] The alumina may be of any crystalline phase structure, such as α-alumina, γ-alumina, δ-alumina, η-alumina, etc., and preferably γ-alumina. The alumina may be commercially available or may be prepared according to techniques known in the art. In one embodiment, the alumina is 100 ml 2 / g~400m 2 / g, preferably 200m 2 / g~300m 2 / g, and a specific surface area of ​​0.4 cm 3 / g~1.0cm 3 / g, preferably 0.5 cm 3 / g~0.8cm 3 / g pore volume. In one variation, the alumina has a pore size of 5.0 nm to 10.0 nm, preferably 6.0 nm to 8.0 nm. In one variation, the alumina has a total amount of weak acids of 0.01 mmol / g to 0.05 mmol / g.

[0029] In one aspect, the present disclosure relates to a method for producing an adsorbent composition for removing polar compounds from low carbon olefins, comprising the steps of: A step of subjecting the molecular sieve, hydrated alumina and alumina to mixing, shaping, drying and calcining to obtain the adsorbent composition, wherein the calcination is carried out at a temperature of less than 400°C.

[0030] In one embodiment, the drying is carried out at a temperature of 50° C. to 150° C. for 3 to 15 hours. The calcination is carried out at a temperature of 200° C. to 400° C., preferably 250° C. to 350° C., for 2 to 10 hours, preferably 3 to 8 hours.

[0031] The forming is preferably extrusion. Any extruder commonly used in the art can be used for forming. The forming may result in a regular or irregular shape. In one embodiment, the forming is extrusion into stripes.

[0032] Peptizers and extrusion aids may be further added to facilitate the mixing and shaping. Examples of suitable peptizers include, for example, nitric acid and citric acid. Examples of suitable extrusion aids include, for example, sesbania powder and methylcellulose. The amounts of peptizers and extrusion aids may be those commonly used in the art.

[0033] In one embodiment, the hydrated alumina is pseudoboehmite. In one variation, the pseudoboehmite is produced by co-precipitation of an aqueous solution of a water-soluble metaaluminate with a nitric acid solution. Examples of water-soluble metaaluminates include sodium metaaluminate and potassium metaaluminate. Preferably, a 0.5 mol / L to 1.5 mol / L sodium metaaluminate solution is reacted with a 0.5 mol / L to 1.5 mol / L nitric acid solution at a pH of 6 to 8. The reaction can be carried out at a temperature of 40°C to 90°C for 0.5 to 3 hours. The pseudoboehmite is obtained as a reaction precipitate, which is then washed and dried for use in producing an adsorbent composition according to the present disclosure.

[0034] In one embodiment, the alumina is produced from pseudoboehmite. Preferably, the production method includes mixing the pseudoboehmite with a solution of polyacrylic acid or a solution of ammonium or sodium polyacrylate, followed by drying and calcination to obtain alumina. In one variation, the mixing includes mixing the pseudoboehmite with a solution of polyacrylic acid in a mass ratio of 1:0.5-1.5, the polyacrylic acid solution having a mass concentration of 0.5%-1.5%. In one variation, the drying is carried out at a temperature of 80°C-150°C for 3-15 hours. The calcination is carried out at a temperature of 400°C-600°C for 3-10 hours.

[0035] The adsorbent compositions of the present disclosure can be used to remove polar compounds from low-carbon olefins. Low-carbon olefins that can be treated include ethylene, propylene, butene, etc. The polar compounds include HO, methanol, ammonia, HS, COS, mercaptans, and other organic compounds containing S or O.

[0036] Without being bound by any theory, it is believed that the adsorbent compositions according to the present disclosure contain a combination of molecular sieves, hydrated alumina, and alumina with various pore structures, acidities, and polarities, thereby adjusting the pore structure, acidity, and polarity of the resulting adsorbent composition. Therefore, the adsorbent compositions according to the present disclosure have significant adsorption capacity, are easy to regenerate, and can reduce and avoid localized temperature increases during adsorption. Additionally, the adsorbent compositions according to the present disclosure unexpectedly have improved compressive strength.

[0037] [Example] The present invention is further illustrated by the following examples, which are intended to illustrate the invention and are not intended to limit the invention in any way.

[0038] (Test Method) 1. Acidity: NH3-TPD tests were performed using a Tianjin Golden Eagle Technology Co., Ltd. PX200A temperature-programmed desorption apparatus under the following conditions: ammonia adsorption temperature 30 °C, carrier gas He, flow rate 30 mL / min, and heating rate 10 °C / min. The desorption curves were fitted to the obtained NH3-TPD profiles to obtain the areas of the corresponding strong or weak acid desorption peaks, thereby calculating the ratio of weak or strong acid to total acid. Here, acidic sites corresponding to the curves at temperatures below 300 °C were considered weak acids, and acidic sites corresponding to the curves at temperatures above 300 °C were considered strong acids. The total amount of acid was measured by applying weight via a microbalance. The total amount of strong or weak acid was calculated based on the total amount of acid and the above ratio.

[0039] 2. Specific surface area: The adsorption curves of the samples were obtained using an American ASAP2600 surface analyzer. Based on the adsorption curves, the specific surface areas of the samples were calculated according to the BET method.

[0040] 3. Pore volume: The adsorption curves of the samples were obtained using an ASAP2600 surface analyzer from the United States. The total pore volume was calculated according to the single-point method.

[0041] 4. Pore size: The adsorption curves of the samples were obtained using an American ASAP2600 surface analyzer. The average pore size of the samples was calculated according to the BJH method.

[0042] 5. Compressive strength: Measured according to HG / T 2782-2001.

[0043] 6. XRD Pattern: The sample was measured using a Siemens X-ray diffractometer (D5005) to obtain an XRD pattern. Specifically, 1 g of sample was obtained and measured using the X-ray diffractometer to obtain an XRD pattern. The measurement conditions included a Cu target, Kα radiation, a solid-state detector, a tube voltage of 40 kV, and a tube current of 40 mA.

[0044] Raw materials: Sodium metaaluminate (manufactured by Sinopharm), 13X (manufactured by Luoyang JALON Micro-nano New Materials Co. Ltd.), NaY (manufactured by Luoyang JALON Micro-nano New Materials Co. Ltd.), Sesbania powder (manufactured by Sinopharm) Example 1 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. Simultaneously, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was operated at pH = 8. The reaction was operated at a temperature of 50°C for 1 hour to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 330 m 2 / g, pore volume is 0.35 cm 3 / g, the amount of weak acid was 0.4 mmol / g, and the pore size was 4.4 nm.

[0045] 20 kg of the pseudo-boehmite was added to 20 kg of a 1.0% by mass polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 100°C for 8 hours, and then calcined at 550°C for 6 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 281 m. 2 / g, pore volume is 0.55 cm 3 / g, the amount of weak acid was 0.02 mmol / g, and the pore size was 7.8 nm.

[0046] 10 kg of 13X, 14 kg of the above pseudoboehmite, 6 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into stripes, and dried at 120°C for 12 hours. The extruded stripes were calcined at 300°C for 5 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.04 mmol / g, and the compressive strength was 80 N / cm.

[0047] The adsorption capacity of saturated saline was tested as follows: 10 g of the adsorbent composition was dried at 120°C for 12 hours, and its weight was designated as weight 1. It was then placed in a dryer containing saturated saline for 24 hours, and its weight was designated as weight 2. The adsorption capacity of the adsorbent composition for saturated saline was calculated using the following formula. The result was 18.9%: Adsorption capacity of saturated saline solution = (weight 2 - weight 1) / weight 1 * 100% The XRD pattern of the adsorbent composition was tested as described above and is shown in FIG.

[0048] Example 2 500 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 0.6 mol / L sodium metaaluminate solution was added to the reactor containing the distilled water at a rate of 30 ml / min, while a 1.0 mol / L nitric acid solution was added at the same time. The addition rate of the nitric acid solution was controlled so that the reaction was operated at pH = 7. The reaction was operated at a temperature of 90°C for 1.5 hours to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 380 m 2 / g, pore volume is 0.32 cm 3 / g, the amount of weak acid was 0.45 mmol / g, and the pore size was 4.3 nm.

[0049] 20 kg of the pseudo-boehmite was added to 10 kg of a 1.5% by mass polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 150°C for 6 hours, and then calcined at 600°C for 5 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 295 m 2 / g, pore volume is 0.65 cm 3 / g, the amount of weak acid was 0.03 mmol / g, and the pore size was 6.7 nm.

[0050] 10 kg of 13X, 10 kg of the pseudoboehmite, 10 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into strips, and dried at 120°C for 12 hours. The extruded strips were calcined at 250°C for 8 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.04 mmol / g, and the compressive strength was 64 N / cm.

[0051] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 22.3%.

[0052] Example 3 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. At the same time, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was operated at pH = 6. The reaction was operated at a temperature of 50°C for 1 hour to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 350 m 2 / g, pore volume 0.37 cm 3 / g, the amount of weak acid was 0.35 mmol / g, and the pore size was 4.7 nm.

[0053] 20 kg of the pseudo-boehmite was added to 30 kg of a 1.0% by mass polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 100°C for 8 hours, and then calcined at 550°C for 6 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 275 m. 2 / g, pore volume is 0.75 cm 3 / g, the amount of weak acid was 0.03 mmol / g, and the pore size was 6.7 nm.

[0054] 6 kg of NaY, 18 kg of the above pseudoboehmite, 8 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into stripes, and dried at 120°C for 12 hours. The extruded stripes were calcined at 350°C for 4 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.02 mmol / g, and the compressive strength was 85 N / cm.

[0055] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 17.8%.

[0056] Example 4 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. At the same time, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was carried out at pH = 8. The reaction was carried out at a temperature of 50°C for 1 hour to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 330 m 2 / g, pore volume is 0.35 cm 3 / g, the amount of weak acid was 0.4 mmol / g, and the pore size was 4.4 nm.

[0057] 20 kg of the pseudo-boehmite was added to 10 kg of a 1.0% by mass polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 100°C for 8 hours, and then calcined at 500°C for 6 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 295 m. 2 / g, pore volume is 0.60 cm 3 / g, the amount of weak acid was 0.03 mmol / g, and the pore size was 7.7 nm.

[0058] 3 kg of 13X, 21 kg of the above pseudoboehmite, 5 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3 wt % solution) was added. The mixture was then kneaded, extruded into stripes, and dried at 120°C for 12 hours. The extruded stripes were calcined at 250°C for 6 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.02 mmol / g, and the compressive strength was 80 N / cm.

[0059] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 15.6%.

[0060] Example 5 10 kg of 13X, 14 kg of pseudoboehmite (obtained from Jiangsu Sanji Industrial Co. Ltd., specific surface area 312 m 2 / g and pore volume 0.34 cm3 / g), 6 kg of alumina (obtained from Shandong Yunneng Catalytic Technology Co., Ltd., specific surface area 297 m 2 / g and pore volume 0.57 cm 3 0.04 mmol / g) and 0.3 kg of Sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into strips, and dried at 120°C for 12 hours. The extruded strips were calcined at 300°C for 5 hours to obtain an adsorbent composition. When tested as described above, the total amount of strong acid in the adsorbent composition was 0.04 mmol / g, and the compressive strength was 40 N / cm.

[0061] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 16.7%.

[0062] (Comparative Example 1) 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. At the same time, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was carried out at pH = 9. The reaction was carried out at a temperature of 50°C for 1 hour to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 410 m 2 / g, pore volume is 0.84 cm 3 / g, the amount of weak acid was 0.4 mmol / g, and the pore size was 8.2 nm.

[0063] 20 kg of the pseudo-boehmite was added to 20 kg of a 1.0 mass % polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 100°C for 8 hours, and then calcined at 400-600°C for 6 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 350 m 2 / g, pore volume is 0.65 cm 3 / g, the amount of weak acid was 0.02 mmol / g, and the pore size was 7.8 nm.

[0064] 10 kg of 13X, 14 kg of the above pseudo-boehmite, 6 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into stripes, and dried at 120°C for 12 hours. The extruded stripes were calcined at 500°C for 5 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.1 mmol / g, and the compressive strength was 13 N / cm.

[0065] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 21.3%.

[0066] (Comparative Example 2) 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. Simultaneously, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was carried out at pH = 5. The reaction was carried out at a temperature of 50°C for 1 hour to obtain a precipitate, which was then washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the resulting pseudo-boehmite was found to be 250 m 2 / g, pore volume 0.28 cm 3 / g, the amount of weak acid was 0.28 mmol / g, and the pore size was 3.6 nm.

[0067] 20 kg of the pseudo-boehmite was added to 20 kg of a 1.0% by mass polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 100°C for 8 hours, and then calcined at 550°C for 6 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 217 m. 2 / g, pore volume is 0.35 cm 3 / g, the amount of weak acid was 0.01 mmol / g, and the pore size was 5.4 nm.

[0068] 10 kg of 13X, 14 kg of the above pseudoboehmite, 6 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into stripes, and dried at 120°C for 12 hours. The extruded stripes were calcined at 450°C for 5 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.07 mmol / g, and the compressive strength was 69 N / cm.

[0069] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 10%.

[0070] (Comparative Example 3) 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. At the same time, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was carried out at pH = 8. The reaction was carried out at a temperature of 50°C for 1 hour to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 330 m 2 / g, pore volume is 0.35 cm 3 / g, the amount of weak acid was 0.4 mmol / g, and the pore size was 4.4 nm.

[0071] 10 kg of 13X, 20 kg of the above pseudo-boehmite, and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3% by weight solution) was added. The mixture was then kneaded, extruded into stripes, and dried at 120°C for 12 hours. The extruded stripes were calcined at 300°C for 5 hours to obtain an adsorbent composition. When tested as described above, the total strong acid content of the adsorbent composition was 0.01 mmol / g, and the compressive strength was 100 N / cm.

[0072] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 18.6%.

[0073] Comparative Example 4 200 ml of distilled water was added to a coprecipitation reactor (2000 ml), and a 1.0 mol / L sodium metaaluminate solution was added to the coprecipitation reactor containing the distilled water at a rate of 10 ml / min. At the same time, a 1.0 mol / L nitric acid solution was added. The addition rate of the nitric acid solution was controlled so that the reaction was carried out at pH = 8. The reaction was carried out at a temperature of 50°C for 1 hour to obtain a precipitate, which was washed and dried to obtain pseudo-boehmite. When tested as described above, the specific surface area of ​​the obtained pseudo-boehmite was found to be 330 m 2 / g, pore volume is 0.35 cm 3 / g, the amount of weak acid was 0.4 mmol / g, and the pore size was 4.4 nm.

[0074] 20 kg of the pseudo-boehmite was added to 20 kg of a 1.0 mass % polyacrylic acid solution. The resulting slurry was mixed uniformly, dried at 100°C for 8 hours, and then calcined at 400-600°C for 6 hours to obtain alumina. When tested as described above, the specific surface area of ​​the resulting alumina was found to be 281 m 2 / g, pore volume is 0.55 cm 3 / g, the amount of weak acid was 0.02 mmol / g, and the pore size was 7.8 nm.

[0075] 10 kg of 13X, 20 kg of alumina, and 0.3 kg of sesbania powder were ground and mixed uniformly, then 5 kg of HNO3 (3 wt % solution) was added and kneaded, extruded into strips, and dried at 120°C for 12 hours. The extruded strips were calcined at 300°C for 5 hours to obtain an adsorbent composition. When tested as described above, the adsorbent composition had a total strong acid content of 0.1 mmol / g and a compressive strength of less than 10 N / cm.

[0076] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 25%.

[0077] (Comparative Example 5) 30 kg of 13X and 0.3 kg of sesbania powder were ground and mixed uniformly, and 5 kg of HNO3 (3 wt % solution) was added, followed by kneading, extrusion into strips, and drying at 120°C for 12 hours. The extruded strips were calcined at 300°C for 5 hours to obtain an adsorbent composition. When tested as described above, the adsorbent composition had a total strong acid content of 0.15 mmol / g and a compressive strength of less than 10 N / cm.

[0078] The adsorption capacity of saturated saline was tested as described in Example 1. The result was 22%.

[0079] The XRD pattern of the adsorbent composition was tested as described above and is shown in FIG.

[0080] The XRD pattern shown in Figure 4 had diffraction peaks at 2θ of 6.03°, 9.87°, 11.6°, 15.32°, 23.16°, 26.5°, and 30.8°.

[0081] (Work Example) This study demonstrates the adsorption performance of the adsorbent composition for the adsorption of NH3, H2S and methanol under various conditions and its regeneration performance.

[0082] Adsorption of NH3 and H2S: 5 g of the adsorbent composition sample was introduced into a fixed-bed reactor, into which a nitrogen gas stream containing 1000 ppm NH3 and 1000 ppm H2S was injected at a flow rate of 100 ml / min. The reactor was maintained at room temperature (25°C) and atmospheric pressure (1 atm). The H2S and NH3 contents in the sample were detected using an Agilent SCD sulfur detector and an NCD nitrogen detector, respectively. Adsorbent breakthrough was considered to have occurred when the NH3 or H2S content in the outlet gas exceeded 1 ppm.

[0083] The adsorbent composition prepared in Example 1 was used as a sample and tested as described above. The content of H2S or NH3 at the outlet of the reactor was detected within a certain time period and plotted as a curve of content vs. time to obtain a breakthrough curve. The breakthrough curve of the adsorbent composition prepared in Example 1 is shown in Figure 1.

[0084] The breakthrough volume was calculated based on the breakthrough time of the adsorbent obtained from the breakthrough curve by the following formula: S=V×t×(Cin-Cout)÷22.4÷1000×M÷mad×10 -6 ; V: gas flow rate (mL / min); t: breakthrough time (minutes); mad: adsorbent loading (g); M: molar mass of H2S or NH3 (L / mol); Cin: content of H2S or NH3 at the inlet (ppm); Cout: H2S or NH3 content at the exhaust outlet (ppm); The adsorbent composition prepared in Example 1 had a breakthrough volume of 2.7% for NH3 and 1.4% for H2S.

[0085] Methanol adsorption: 20 g of the adsorbent composition was introduced into a fixed-bed reactor. A nitrogen gas flow was injected at a flow rate of 100 ml / min and bubbled through a vessel containing a methanol solution at 30°C, and then passed through the reactor at a temperature of 50°C. The outlet gas was detected by gas chromatography to determine whether any methanol signal peak was present. If a methanol signal peak was present, the adsorbent was saturated. The weights of the adsorbent before and after adsorption saturation were detected using a balance, and the methanol adsorption capacity of the adsorbent composition sample was calculated. Methanol adsorption capacity = (weight of adsorbent composition after adsorption saturation - weight of adsorbent composition before adsorption saturation) / weight of adsorbent composition before adsorption saturation * 100%.

[0086] The adsorbent composition prepared in Example 1 was used as a sample and tested as described above. The adsorbent composition prepared in Example 1 had a methanol adsorption capacity of 15%.

[0087] Effect of regeneration on the performance of the adsorbent composition: A saturated sample of the adsorbent was heated at 180°C for 5 hours to regenerate, and a regenerated sample was obtained. The regenerated sample was tested as described above to obtain the adsorption capacity of saturated brine, the breakthrough volume of NH, the breakthrough volume of HS, and the adsorption capacity of methanol of the regenerated sample.

[0088] The adsorbent composition prepared in Example 1 was regenerated once as described above. The regenerated sample tested to have an adsorption capacity for saturated brine of 18.9%, a breakthrough volume for NH3 of 2.8%, a breakthrough volume for HS of 1.3%, and an adsorption capacity for methanol of 15%.

[0089] Adsorption of NH3, H2S, and methanol in the presence of ethylene: The above test was repeated except that a nitrogen gas stream containing 1000 ppm NH3 and 10% ethylene, a nitrogen gas stream containing 1000 ppm H2S and 10% ethylene, and a nitrogen gas stream containing 5% ethylene were passed through the methanol solution, respectively.

[0090] The adsorbent composition prepared in Example 1 was used in the above test, and the results showed a breakthrough volume of 2.8% for NH, a breakthrough volume of 1.3% for H2S, and an adsorption capacity of 15% for methanol.

[0091] Reproducibility: 5 g of the adsorbent composition sample was introduced into a fixed-bed reactor, and a nitrogen gas stream containing 1000 ppm NH3 and 5% propylene was injected into the fixed-bed reactor at a flow rate of 240 ml / min. The reactor was maintained at room temperature (25°C) and atmospheric pressure (1 atm). The NH3 content was detected using an Agilent NCD nitrogen detector. When the NH3 content in the outlet gas exceeded 1 ppm, breakthrough of the adsorbent was considered to have occurred. A breakthrough curve of the adsorbent composition was obtained, and the NH3 breakthrough volume was calculated. The used sample was heated at 180°C for 5 hours for regeneration to obtain a regenerated sample. The above test was repeated using the regenerated sample, and the NH3 breakthrough volume of the regenerated sample was obtained. The regeneration and test were repeated 15 times, and the NH3 breakthrough volume of each regenerated sample was obtained.

[0092] The adsorbent composition of Example 1 was used in the above test. The fresh adsorbent composition had a breakthrough volume of 2.8% NH. The adsorbent composition that had been regenerated once had a breakthrough volume of 2.8% NH. The adsorbent composition that had been regenerated 15 times had a breakthrough volume of 2.7% NH.

[0093] Figure 2 shows the NH3-TPD curve of the adsorbent composition of Example 1, which has been regenerated several times. It can be seen from this figure that the adsorbent composition of Example 1 can remove NH3 from the adsorbent at about 150°C, and therefore can be regenerated online, and the adsorption performance is well maintained even after 15 regenerations.

[0094] The above test was repeated using the adsorbent composition of Comparative Example 1. The fresh adsorbent composition had a breakthrough volume of 2.9% NH3. The adsorbent composition that had been regenerated once had a breakthrough volume of 2.7% NH3. The adsorbent composition that had been regenerated 15 times had a breakthrough volume of 2.0% NH3.

[0095] The above test was repeated using the adsorbent composition of Comparative Example 5. The fresh adsorbent composition had a breakthrough volume of 3.2% NH3. The adsorbent composition that had been regenerated once had a breakthrough volume of 1.0% NH3. The adsorbent composition that had been regenerated five times had a breakthrough volume of 0.2% NH3. [Brief explanation of the drawings]

[0096] [Figure 1] 1 shows the breakthrough curves of the adsorbent composition prepared in Example 1 for the adsorption of NH3 and H2S. [Figure 2] 1 shows the NH3-TPD curve of the adsorbent composition prepared in Example 1 after one or more regenerations. [Figure 3] 1 shows the XRD pattern of the adsorbent composition prepared in Example 1. [Figure 4] 1 shows the XRD pattern of the adsorbent composition prepared in Comparative Example 5.

Claims

Claim 1: An adsorbent composition for removing polar compounds from C2-C4 olefins, comprising: the adsorbent composition comprises a molecular sieve, hydrated alumina, and alumina; The adsorbent composition comprises, by weight: a) 10 to 50 parts of said molecular sieve; b) 20 to 55 parts, calculated as alumina, of said hydrated alumina; c) 5 parts to 35 parts of said alumina; the adsorbent composition has a total amount of strong acids of less than 0.05 mmol / g; The adsorbent composition, wherein the polar compound comprises H2O, methanol, ammonia, H2S, or COS.

2. The adsorbent composition comprises, by weight: a) 20 to 40 parts of said molecular sieve; b) 30 to 45 parts, calculated as alumina, of said hydrated alumina; c) 8 parts to 30 parts of said alumina; 2. The adsorptive composition of claim 1, wherein the adsorptive composition has a total amount of strong acids of 0.01 mmol / g to 0.04 mmol / g.

3. The XRD pattern of the adsorbent composition is 2. The adsorbent composition of claim 1, characterized in that it comprises diffraction peaks at 2θ of 6.03°, 13.47°, 15.32°, 28.01°, 37.96° and 49.28°.

4. The XRD pattern of the adsorbent composition 2. The adsorbent composition of claim 1, characterized in that it comprises diffraction peaks at 2θ of 6.03°, 13.47°, 15.32°, 28.01°, 23.16°, 37.96°, 46.34°, 49.28° and 66.8°.

5. The adsorbent composition of claim 1, wherein the XRD pattern of the adsorbent composition comprises diffraction peaks at 2θ as outlined in the following table: 【Table 1】 。

6. The hydrated alumina is comprising one or more of pseudoboehmite, boehmite, gibbsite and bayerite; or The hydrated alumina is 300 ml ２ / g~400m ２ / g, and a specific surface area of ​​0.3 cm ３ / g to 0.4 cm ３ 10. The adsorbent composition of claim 1, characterized in that it has a pore volume of 1000 .mu.m / g.

7. The adsorbent composition described in claim 1, characterized in that the hydrated alumina is pseudoboehmite.

8. The alumina is 200m ２ / g to 300m ２ / g, and a specific surface area of ​​0.5 cm ３ / g to 0.8 cm ３ 10. The adsorbent composition of claim 1, characterized in that it has a pore volume of 1000 .mu.m / g.

9. The molecular sieve is 2. The adsorbent composition according to claim 1, characterized in that it is one or two selected from the group consisting of X-type molecular sieves and Y-type molecular sieves.

10. The adsorbent composition described in claim 1, characterized in that the molecular sieve is one or two selected from the group consisting of 13X and NaY.

11. A method for producing an adsorbent composition according to any one of claims 1 to 10, characterized in that it comprises the following steps: A step of mixing, shaping, drying, and calcining a molecular sieve, a hydrated alumina, and alumina to obtain the adsorbent composition, The calcination is carried out at a temperature of less than 400°C.

12. 12. The method of claim 11, wherein the hydrated alumina is pseudoboehmite.

13. The pseudo-boehmite is produced by a co-precipitation reaction between an aqueous solution of a water-soluble metaaluminate and a nitric acid solution, and the water-soluble metaaluminate is one or two of sodium metaaluminate and potassium metaaluminate; 13. The method according to claim 12, characterized in that the reaction is operated at pH=6-8.

14. 12. The method according to claim 11, characterized in that the calcination is carried out at a temperature between 200°C and 400°C for a time between 2 hours and 10 hours.

15. The method of claim 11, wherein the calcination is carried out at a temperature of 250°C to 350°C for a period of 3 to 8 hours.

16. When removing polar compounds from C2-C4 olefins, Use of an adsorbent composition according to any one of claims 1 to 10 or an adsorbent composition produced by a method according to any one of claims 11 to 15, The polar compound comprises H2O, methanol, ammonia, H2S or COS.

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