CN110026151B - Method for improving adsorption capacity and strength of binderless nalsx molecular sieve - Google Patents
Method for improving adsorption capacity and strength of binderless nalsx molecular sieve Download PDFInfo
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Abstract
The invention discloses a method for improving the adsorption capacity and strength of a binderless nalsx molecular sieve. The preparation method comprises the following steps: the method comprises the steps of taking nalsx molecular sieve raw powder, white carbon black and kaolin as raw materials, adding a pore-forming agent, and preparing the non-adhesive nalsx molecular sieve through procedures of mixing and forming, drying and roasting, water absorption, sodium hydroxide treatment, secondary drying and roasting and the like. Compared with the binder which is completely kaolin, the adsorption capacity and strength of the molecular sieve can be obviously improved by using kaolin and white carbon black as the binder. When the mass content of nalsx raw powder is 66-84%, the mass content of white carbon black is 5-8%, the mass content of kaolin is 10-25%, and the mass content of pore-forming agent is 1%, the water absorption capacity of the prepared molecular sieve is 31.9-33.3%, which accounts for 92-98% of the water absorption capacity of pure nalsx raw powder; when the water absorption capacity of the 1.5mm columnar binderless molecular sieve is 31.9 percent, the strength reaches 60N.
Description
Technical Field
The invention belongs to the field of preparation of molecular sieve adsorption materials, and particularly relates to a method for improving the adsorption capacity and strength of a binderless nalsx molecular sieve.
Background
The nalsx (the molar ratio of silicon oxide to aluminum oxide is 2) powder has larger water adsorption capacity after roasting and activation due to lower silicon-aluminum ratio, and the loss by burning is larger and is about 23-24%; after kaolin (the purity is more than 90 percent) is roasted at the high temperature of 600-700 ℃, the loss of ignition is about 15 percent. In the process of preparing the binderless nalsx molecular sieve by using kaolin, the strength is not high due to larger weight loss difference and larger material shrinkage rate when the kaolin and the nalsx molecular sieve are roasted.
The white carbon black as amorphous silicon dioxide reacts with sodium hydroxide lye to generate soluble silicate which can provide silicon source for molecular sieve synthesis. The water content of the white carbon black is about 2-3%, and the white carbon black has less weight loss after being roasted at high temperature.
The national patents CN1234782A, CN106698458A, CN101524637A, CN107159105A and the like mainly adopt zeolizable binders for conversion, and the zeolizable binders are mainly kaolin or mixtures of kaolin and other clays. With the increase of the kaolin content, the conversion rate is not high when the pure kaolin is converted into the molecular sieve, and the water absorption capacity of the prepared molecular sieve is low. Foreign researchers also mainly use pure kaolin for conversion, and the white carbon black rain kaolin is adopted, so that the strength and the adsorption capacity of the enhanced molecular sieve are not reported in related researches.
In the prior art, in the process of converting kaolin into the x-type molecular sieve, pure kaolin is mainly used as a binder, the content of the pure kaolin generally accounts for 10-15% of the total mass of a mixture, after molding and high-temperature roasting, water glass, soluble silicon and the like are added to provide a silicon source for preparing the molecular sieve when alkali liquor is used for aging and crystallization, and as the solution has high viscosity, silicon ions enter the inside of a molding material slowly from the surface of the molding material, the generation rate of crystal nuclei is slow, so that the conversion rate is low, the adsorption capacity and the strength of a conversion product are low, and the binder-free molecular sieve with high strength and water absorption capacity cannot be obtained. According to the preparation method, nalsx raw powder is used as an active component, kaolin and white carbon black are used as a binder, the white carbon black is added during mixing due to the large specific surface area of the white carbon black, a silicon source can be uniformly dispersed in a forming material, the dispersibility of the kaolin in a mixture is changed, alkali liquor ions can rapidly enter the material, the alkali liquor and the white carbon black dissolved in the forming material rapidly react, and more x-type crystal nuclei are provided for a synthesized molecular sieve; meanwhile, after the white carbon black is introduced, the mass ratio of water added in the formula to the crystallized material during crystallization can be improved, the transmission of alkali liquor in the material is facilitated, and the uniformity of a sample in the crystallization process is improved; compared with the binderless molecular sieve which is completely converted from kaolin and white carbon black, the prepared high-purity nalsx molecular sieve has higher water absorption capacity and strength, and can prepare the binderless molecular sieve with both high water absorption capacity and high strength.
Disclosure of Invention
This patent uses nalsx molecular sieve powder, white carbon black and kaolin as raw materials, its characterized in that:
(1) preparing materials: mixing kaolin, white carbon black, nalsx molecular sieve powder and a pore-forming agent according to a certain proportion;
(2) molding: pelletizing by using a disc pelletizer or extruding into strips by using a strip extruding machine;
(3) primary drying and roasting: drying at low temperature, and then roasting at high temperature;
(4) saturated water absorption: after the roasted material absorbs water and is saturated for later use;
(5) alkali liquor treatment: carrying out crystallization treatment by adopting sodium hydroxide lye;
(6) secondary drying and roasting: and drying and roasting the crystallized sample, testing the water absorption capacity and the strength of the sample, and comparing the water absorption capacity with the water absorption capacity of pure nalsx raw powder.
The method is characterized in that the raw nalsx powder, the white carbon black and the kaolin are mixed, wherein the raw nalsx powder, the white carbon black and the kaolin are mixed, and the mixture is mixed, wherein the nalsx raw powder, the white carbon black and the kaolin are mixed together, and the pore-forming agent are mixed together when the mass content of the nalsx raw powder, the white carbon black, the kaolin and the kaolin is respectively 66-84%, 10-25% and 1%, respectively; the purity of the kaolin is more than or equal to 92 percent, and the purity of the white carbon black is more than or equal to 97 percent; the pore-forming agent can be organic substances such as sodium carboxymethylcellulose, starch, lignin and the like;
the high-temperature roasting is characterized in that the roasting condition is that roasting is carried out for 2-4 hours at the temperature of 600-650 ℃;
the alkali liquor treatment is characterized in that sodium oxide, aluminum oxide, silicon oxide and water in the molding material and the mixed solution during crystallization meet the following conditions: the molar ratio of the silicon oxide to the aluminum oxide is 2.8-3.5; the molar ratio of water to sodium oxide is 40-50; the molar ratio of sodium oxide to silicon oxide is 1-1.5. Aging at 20-30 ℃ for 10-14 hours, and crystallizing at 85-95 ℃ for 7-15 hours;
the drying roasting is characterized in that the secondary roasting temperature is 600-650 ℃;
the prepared molecular sieve product is characterized in that the water absorption capacity is 31.9-33.3%, which is 92-98% of the water absorption capacity of pure nalsx raw powder; when the water absorption capacity of the 1.5mm columnar binderless molecular sieve is 31.9 percent, the strength reaches 60N.
The invention has the advantages that:
when pure kaolin is adopted to synthesize the binderless molecular sieve in the conventional technology, in order to obtain the binderless molecular sieve with high water absorption capacity, the kaolin conversion rate is low, so that only the addition amount of the kaolin can be reduced, and the strength of the molecular sieve is lower. According to the invention, the kaolin and the white carbon black binder are adopted, the mass of the kaolin accounts for 10-25% of the total mass, and the white carbon black is added, so that the dispersibility of the kaolin in the raw powder is improved, and the kaolin is favorably converted; in addition, in the process of converting pure kaolin into the nalsx molecular sieve, the required water-sodium ratio is generally 40-50 and the alkalinity is 1-2 in the process of converting the binder into the x-type molecular sieve, if the water-sodium ratio is increased, the rest A-type mixed crystals are easily generated in the crystallization process, when the content of the pure kaolin is 10-15%, the mass ratio of water to solid materials is lower and is close to 1 in the crystallization process, particularly when the content of the kaolin is 10%, and when the columnar molecular sieve is used for crystallization, the water-sodium ratio is low (the A-type mixed crystals are easily generated by adopting a high water-sodium ratio), water cannot cover the molecular sieve, so that the upper part materials cannot be crystallized, the crystallization is not uniform, the alkali solution is not favorable for diffusion transmission, the sample is easy to crush in the stirring process, and the crystallization uniformity of the sample is influenced. By adding the white carbon black, compared with the method of completely adopting the kaolin binder, when the water-sodium ratio is the same, the ratio of water to the solid material is relatively large, so that the materials are uniformly stirred in the crystallization process, and the uniformity of the final crystallized sample is improved. By adding a proper amount of white carbon black, kaolin and the white carbon black are converted into the binderless nalsx molecular sieve with large adsorption capacity and high strength, and the binderless molecular sieve with large water absorption capacity and high strength can be prepared.
Drawings
FIG. 1 SEM image of binderless sample 1-1
FIG. 2 SEM pictures of binderless samples 1-5
FIG. 3 SEM image of binderless sample 2-1
FIG. 4 SEM image of binderless sample 2-3
FIG. 5 SEM photograph of binderless sample 5-1
FIG. 6 is XRD patterns of a sample without a binder and pure NaLSX powder synthesized with different soil contents when the white carbon black is 5%.
Detailed Description
The water absorption capacity of the molecular sieve in the embodiment is detected according to the national standard GB/T-6287. The strength test of the molecular sieve adopts an intelligent particle strength tester.
Example 1
Mixing kaolin (10% by mass and 92% by mass) and white carbon black (5% by mass and 94% by mass) with nalsx molecular sieve raw powder (86%) uniformly, extruding into strips with the diameter of 1.5mm by using a strip extruding machine, drying, roasting at 650 ℃ for 2h, and exposing in air for saturation and water absorption. Adding the saturated water-absorbed nalsx molecular sieve balls into a mixed solution of water, sodium hydroxide and sodium metaaluminate. The contents of sodium oxide, aluminum oxide, silicon oxide and water in the molding material and the mixed solution during aging crystallization meet the following conditions: the molar ratio of the silicon oxide to the aluminum oxide is 2.8-3.5; the molar ratio of water to sodium oxide is 40-50; the molar ratio of sodium oxide to silicon oxide is 1-1.5. Aging at 20-30 ℃ for 10-14 hours, and crystallizing at 85-95 ℃ for 7-15 hours; after washing, drying and roasting, sample 1-1 is obtained. In sample 1-1, at a temperature of 25 ℃ and a relative humidity of 75%, the water absorption capacity of the sample reaches 33.3%, the water absorption capacity of the pure nalsx molecular sieve raw powder is 34%, and the water absorption capacity of the sample 1-1 accounts for 98% of that of the nalsx molecular sieve raw powder. The intensity was 22N.
Example 2
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 10%, 2% and 87%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 1-2 absorbed 33% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 97% of the water absorption of nalsx molecular sieve raw powder. The intensity was 16N.
Example 3
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 10%, 8% and 81%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 1-3 absorbed 33.3% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 98% of the water absorption of nalsx molecular sieve raw powder. The intensity was 20N.
Example 4
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 10%, 9% and 80%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 1-4 absorbed 33.3% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 98% of the water absorption of nalsx molecular sieve raw powder. The formed sample has more cracks and is fragile. The intensity was 16N.
Comparative example 1
The mass fractions of kaolin, white carbon black and raw powder in example 1 were respectively changed to 10%, 0% and 89%, water glass was used to supplement the silicon source, the other conditions were not changed, and the formulation and the aging crystallization conditions were fixed, so that samples 1-5 absorbed 32% of water, the water absorption of the pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 94% of the nalsx molecular sieve raw powder. The sample strength was 13N.
From examples 1 to 4 and comparative example 1, it can be seen that when the kaolin clay mass fraction is 10% and the white carbon black content is 5 to 8%, the water absorption capacity of the prepared binderless molecular sieve sample is 33.3%, the strength reaches about 20 to 22N, and the water absorption capacity and strength are superior to those of the binderless molecular sieve sample 1 to 4 prepared from pure kaolin clay. Comparing fig. 1 with fig. 2, the new crystal generated on the surface of Nalsx in the sample 1-1 has more clear edge angle, is octahedral, and has better crystallization. The Nalsx surface in the sample 1-5 is crack-shaped, and the edge angle is not clear, which indicates that the metakaolin generated after the kaolin is roasted cannot be completely crystallized, and the crystallization effect is not good. As can be seen from fig. 6, the crystal produced in example 1 was compared with the pure Nalsx powder, and no heterocrystal phase was produced.
Example 5
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 15%, 5% and 79%, respectively, and the other conditions were not changed, and the formulation and the aging crystallization conditions were fixed, so that sample 2-1 absorbed 32.6% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 96% of the water absorption of nalsx molecular sieve raw powder. The sample intensity was 37N.
Example 6
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 15%, 8% and 76%, respectively, and the other conditions were not changed, and the formulation and the aging crystallization conditions were fixed, so that sample 2-2 had a water absorption of 32.6%, pure nalsx molecular sieve raw powder had a water absorption of 34%, and accounted for 96% of the water absorption of the nalsx molecular sieve raw powder. The sample strength was 35N.
Comparative example 2
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 15%, 0% and 84%, respectively, and water glass was used to supplement the silicon source, while the other conditions were unchanged, and the formulation and the aging crystallization conditions were fixed, so that sample 2-3 had a water absorption of 31.3%, pure nalsx molecular sieve raw powder had a water absorption of 34%, and accounted for 92% of the water absorption of the nalsx molecular sieve raw powder. The sample strength was 30N.
From examples 5-6 and comparative example 2, when the mass fraction of kaolin is 15% and the white carbon black content is 5-8%, the water absorption capacity of the prepared binderless molecular sieve sample is 32.6%, the strength reaches about 35-37N, and the water absorption capacity and the strength are superior to those of the binderless molecular sieve sample 2-3 prepared from pure kaolin. Comparing fig. 3 with fig. 4, most of the newly formed crystal edges on the surface of Nalsx in the 2-1 sample are more distinct and octahedral. The Nalsx surface in the sample 2-3 is crack-shaped, the edge angle is not clear, mainly because metakaolin generated after the kaolin is roasted cannot be completely crystallized, and the crystallization effect is not good. As can be seen from fig. 6, the crystal produced in example 5 was compared with the pure Nalsx powder, and no heterocrystal phase was produced.
Example 7
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 20%, 5% and 74%, respectively, and the other conditions were unchanged, and the formula and the aging crystallization conditions were fixed, so that sample 3-1 had a water absorption of 32%, pure nalsx molecular sieve raw powder had a water absorption of 34%, and accounted for 94% of the water absorption of the nalsx molecular sieve raw powder. The sample strength was 42N.
Comparative example 3
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 20%, 0% and 79%, respectively, and water glass was used to supplement the silicon source, while the other conditions were unchanged, and the formulation and the aging crystallization conditions were fixed, so that sample 3-2 had a water absorption of 31%, pure nalsx molecular sieve raw powder had a water absorption of 34%, and the water absorption accounted for 91% of the water absorption of the nalsx molecular sieve raw powder. The sample strength was 35N.
From the example 7 and the comparative example 3, when the kaolin mass fraction is 20% and the white carbon black content is 6%, the water absorption of the prepared binderless molecular sieve sample is 32%, the strength reaches about 42N, and the water absorption and the strength are superior to those of the binderless molecular sieve sample 3-2 prepared from pure kaolin. As can be seen from fig. 6, the crystal produced in example 7 was compared with the pure Nalsx powder, and no heterocrystal phase was produced.
Example 8
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 25%, 8% and 66%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 4-1 absorbed 31.3% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 92% of the water absorption of nalsx molecular sieve raw powder. The sample strength was 55N.
Example 9
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 25%, 5% and 69%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 4-2 absorbed 31.3% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 92% of the water absorption of nalsx molecular sieve raw powder. The sample strength was 60N.
Example 10
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 25%, 10% and 64%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 4-1 absorbed 31.3% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 92% of the water absorption of nalsx molecular sieve raw powder. The sample is not easy to form, has cracks and is easy to break.
Example 11
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 25%, 2% and 72%, respectively, and the other conditions were unchanged, and the formulation and aging crystallization conditions were fixed, so that sample 4-2 absorbed 30.6% of water, the water absorption of pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 90% of the water absorption of nalsx molecular sieve raw powder. The sample strength was 45N.
Comparative example 4
The mass fractions of kaolin, white carbon black and raw powder in example 1 were changed to 25%, 0% and 74%, respectively, water glass was used to supplement the silicon source, the other conditions were not changed, and the formulation and the aging crystallization conditions were fixed, so that a sample 4-3 absorbed 30.3% of water, the water absorption of the pure nalsx molecular sieve raw powder was 34%, and the water absorption accounted for 89% of the water absorption of the nalsx molecular sieve raw powder. The sample strength was 40N.
From the examples 8 to 9 and the comparative example 4, when the kaolin clay mass fraction is 25% and the white carbon black content is 3% to 7%, the water absorption capacity of the prepared binderless molecular sieve sample is 31.3%, the strength reaches about 55N to 60N, and the water absorption capacity and the strength are superior to those of the binderless molecular sieve sample 4-3 prepared from pure kaolin clay.
Comparative example 5 (Synthesis of type A molecular sieves from sodium hydroxide solution)
The mass fractions of kaolin, white carbon black and raw powder in example 1 are respectively changed into 10%, 0% and 89%, and the contents of sodium oxide, aluminum oxide, silicon oxide and water in the molding material and the mixed solution during aging and crystallization meet the following conditions: the molar ratio of silicon oxide to aluminum oxide is 2; the molar ratio of water to sodium oxide is 40-50; the molar ratio of sodium oxide to silicon oxide is 1-1.5. Crystallizing at 95 ℃ for 4-5 hours to obtain a sample 5-1 with water absorption of 32%, wherein the water absorption of the pure nalsx molecular sieve raw powder is 34%, and the water absorption accounts for 94% of the water absorption of the nalsx molecular sieve raw powder. The SEM image of sample 5-1 is shown in FIG. 5.
Comparative example 6 (Synthesis of type A molecular sieves from sodium hydroxide solution)
The mass fractions of kaolin, white carbon black and raw powder in example 1 are respectively changed to 15%, 0% and 84%, and the contents of sodium oxide, aluminum oxide, silicon oxide and water in the molding material and the mixed solution during aging and crystallization meet the following conditions: the molar ratio of silicon oxide to aluminum oxide is 2; the molar ratio of water to sodium oxide is 40-50; the molar ratio of sodium oxide to silicon oxide is 1-1.5. Crystallizing at 95 ℃ for 4-5 hours to obtain a sample 6-1 with water absorption of 3O.6%, wherein the water absorption of the pure nalsx molecular sieve raw powder is 34%, and the water absorption accounts for 90% of the water absorption of the nalsx molecular sieve raw powder.
Comparative example 7
The mass fractions of kaolin, white carbon black and raw powder in example 1 are respectively changed to 20%, 0% and 79%, and the contents of sodium oxide, aluminum oxide, silicon oxide and water in the molding material and the mixed solution during aging and crystallization meet the following conditions: the molar ratio of silicon oxide to aluminum oxide is 2; the molar ratio of water to sodium oxide is 40-50; the molar ratio of sodium oxide to silicon oxide is 1-1.5. Crystallizing at 95 ℃ for 4-5 hours to obtain a sample 7-1 with 29.6% of water absorption, wherein the water absorption of the pure nalsx molecular sieve raw powder is 34% and accounts for 87% of the water absorption of the nalsx molecular sieve raw powder.
The comparison of comparative examples 1 and 5, comparative examples 2 and 6, and comparative examples 3 and 7 shows that when pure kaolin is used as the binder, the conversion of the sample of the type X molecular sieve using the mixed solution of sodium hydroxide and sodium silicate is better than the conversion of the sample of the type A binderless molecular sieve using the sodium hydroxide solution. The X-type molecular sieve converted by using the white carbon black as the silicon source is better than the A-type molecular sieve without the binding agent and adopting the sodium hydroxide solution. Comparing the crystal form shown in fig. 1 with that shown in fig. 5, the crystal form shown in fig. 1 is octahedral, has clear edges and corners and is mainly an X-type molecular sieve; the crystal morphology in fig. 5 is tetrahedral, and the corners are fuzzy, which shows that the sample generated by crystallization in fig. 5 is mainly a type molecular sieve.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various changes and modifications can be made without departing from the overall concept of the invention, and these should be considered as the protection scope of the present invention, which will not affect the effect of the implementation of the present invention and the practicability of the patent.
Claims (6)
1. A method for improving the adsorption capacity and strength of a binderless nalsx molecular sieve takes nalsx molecular sieve powder, white carbon black and kaolin as raw materials, and is characterized in that:
(1) preparing materials: adding a pore-forming agent into the high-purity kaolin, the high-purity white carbon black and the nalsx molecular sieve powder for mixing;
(2) molding: pelletizing by using a disc pelletizer or extruding into strips by using a strip extruding machine;
(3) primary drying and roasting: drying at low temperature, and roasting at high temperature;
(4) saturated water absorption: after the roasted material absorbs water and is saturated for later use;
(5) alkali treatment: carrying out aging crystallization treatment in a mixed alkali solution of sodium hydroxide and sodium metaaluminate;
(6) secondary drying and roasting: and drying and roasting the crystallized sample again, testing the water absorption capacity and the strength of the sample, and comparing the water absorption capacity with the water absorption capacity of pure nalsx raw powder.
2. The method according to claim 1, wherein the mass content of the nalsx molecular sieve powder in the mixed material is 66-84%, the mass content of the high-purity white carbon black is 5-8%, the mass content of the high-purity kaolin is 10-25%, and the mass content of the pore-forming agent is 1%; the purity of the high-purity kaolin is more than or equal to 92 percent, and the purity of the high-purity white carbon black is more than or equal to 97 percent; the pore-forming agent is sodium carboxymethyl cellulose, starch or lignin.
3. The method according to claim 1, wherein the primary roasting condition is 600 to 650 ℃ for 2 to 4 hours.
4. The method according to claim 1, wherein the alkali treatment conditions are that sodium oxide, aluminum oxide, silicon oxide and water in the molding material and in the mixed solution during crystallization satisfy the following conditions that the ratio of the mole number of silicon oxide to the mole number of aluminum oxide is 2.8-3.5; the ratio of the mole number of water to the mole number of sodium oxide is 40-50; the ratio of the mole number of sodium oxide to the mole number of silicon oxide is 1-1.5.
5. The method of claim 1, wherein the aging crystallization conditions are aging at 20-30 ℃ for 10-14 h and crystallization at 85-95 ℃ for 7-15 h.
6. The method of claim 1, wherein the water absorption capacity of the prepared molecular sieve is 31.9-33.3% and is 92-98% of the water absorption capacity of the pure nalsx raw powder; when the water absorption capacity of the 1.5mm columnar binderless molecular sieve is 31.9 percent, the strength reaches 60N.
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| CN114177883B (en) * | 2021-12-29 | 2023-08-18 | 洛阳建龙微纳新材料股份有限公司 | Ba/Cs/Ni-LSX molecular sieve and preparation method and application thereof |
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