CN116902934B - Preparation method of aluminum hypophosphite - Google Patents
Preparation method of aluminum hypophosphite Download PDFInfo
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- CN116902934B CN116902934B CN202311159758.5A CN202311159758A CN116902934B CN 116902934 B CN116902934 B CN 116902934B CN 202311159758 A CN202311159758 A CN 202311159758A CN 116902934 B CN116902934 B CN 116902934B
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- 229910001377 aluminum hypophosphite Inorganic materials 0.000 title claims abstract description 134
- 238000002360 preparation method Methods 0.000 title claims abstract description 31
- 238000003756 stirring Methods 0.000 claims abstract description 76
- DIZPMCHEQGEION-UHFFFAOYSA-H aluminium sulfate (anhydrous) Chemical compound [Al+3].[Al+3].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O DIZPMCHEQGEION-UHFFFAOYSA-H 0.000 claims abstract description 56
- KOUDKOMXLMXFKX-UHFFFAOYSA-N sodium oxido(oxo)phosphanium hydrate Chemical compound O.[Na+].[O-][PH+]=O KOUDKOMXLMXFKX-UHFFFAOYSA-N 0.000 claims abstract description 53
- WNROFYMDJYEPJX-UHFFFAOYSA-K aluminium hydroxide Chemical compound [OH-].[OH-].[OH-].[Al+3] WNROFYMDJYEPJX-UHFFFAOYSA-K 0.000 claims abstract description 43
- 239000012043 crude product Substances 0.000 claims abstract description 19
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims abstract description 19
- 238000006243 chemical reaction Methods 0.000 claims abstract description 17
- 238000001914 filtration Methods 0.000 claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 47
- 239000008367 deionised water Substances 0.000 claims description 44
- 229910021641 deionized water Inorganic materials 0.000 claims description 44
- 239000000047 product Substances 0.000 claims description 41
- 238000000034 method Methods 0.000 claims description 13
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 12
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 12
- 238000005406 washing Methods 0.000 claims description 11
- JGDITNMASUZKPW-UHFFFAOYSA-K aluminium trichloride hexahydrate Chemical compound O.O.O.O.O.O.Cl[Al](Cl)Cl JGDITNMASUZKPW-UHFFFAOYSA-K 0.000 claims description 10
- 229940009861 aluminum chloride hexahydrate Drugs 0.000 claims description 10
- 238000000227 grinding Methods 0.000 claims description 9
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 8
- 238000001035 drying Methods 0.000 claims description 6
- 238000004140 cleaning Methods 0.000 claims description 3
- 239000002245 particle Substances 0.000 abstract description 64
- 238000009826 distribution Methods 0.000 abstract description 17
- 238000005979 thermal decomposition reaction Methods 0.000 abstract description 12
- 239000003063 flame retardant Substances 0.000 abstract description 5
- 230000001276 controlling effect Effects 0.000 description 63
- 238000003921 particle size analysis Methods 0.000 description 12
- XYFCBTPGUUZFHI-UHFFFAOYSA-N Phosphine Chemical compound P XYFCBTPGUUZFHI-UHFFFAOYSA-N 0.000 description 8
- 229910052782 aluminium Inorganic materials 0.000 description 5
- -1 aluminum ions Chemical class 0.000 description 5
- 238000000354 decomposition reaction Methods 0.000 description 5
- 230000000694 effects Effects 0.000 description 5
- 239000000203 mixture Substances 0.000 description 5
- FAPWRFPIFSIZLT-UHFFFAOYSA-M Sodium chloride Chemical compound [Na+].[Cl-] FAPWRFPIFSIZLT-UHFFFAOYSA-M 0.000 description 4
- 239000005708 Sodium hypochlorite Substances 0.000 description 4
- VSCWAEJMTAWNJL-UHFFFAOYSA-K aluminium trichloride Chemical compound Cl[Al](Cl)Cl VSCWAEJMTAWNJL-UHFFFAOYSA-K 0.000 description 4
- 238000013211 curve analysis Methods 0.000 description 4
- 229910000073 phosphorus hydride Inorganic materials 0.000 description 4
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 description 4
- RNFJDJUURJAICM-UHFFFAOYSA-N 2,2,4,4,6,6-hexaphenoxy-1,3,5-triaza-2$l^{5},4$l^{5},6$l^{5}-triphosphacyclohexa-1,3,5-triene Chemical compound N=1P(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP(OC=2C=CC=CC=2)(OC=2C=CC=CC=2)=NP=1(OC=1C=CC=CC=1)OC1=CC=CC=C1 RNFJDJUURJAICM-UHFFFAOYSA-N 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 2
- 230000002378 acidificating effect Effects 0.000 description 2
- 229940063656 aluminum chloride Drugs 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 230000000052 comparative effect Effects 0.000 description 2
- 239000010419 fine particle Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 239000011780 sodium chloride Substances 0.000 description 2
- 229910052938 sodium sulfate Inorganic materials 0.000 description 2
- 235000011152 sodium sulphate Nutrition 0.000 description 2
- KWSLGOVYXMQPPX-UHFFFAOYSA-N 5-[3-(trifluoromethyl)phenyl]-2h-tetrazole Chemical compound FC(F)(F)C1=CC=CC(C2=NNN=N2)=C1 KWSLGOVYXMQPPX-UHFFFAOYSA-N 0.000 description 1
- 238000010669 acid-base reaction Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 238000005119 centrifugation Methods 0.000 description 1
- 239000013078 crystal Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000002274 desiccant Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000003230 hygroscopic agent Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000010137 moulding (plastic) Methods 0.000 description 1
- 229920000642 polymer Polymers 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 230000001105 regulatory effect Effects 0.000 description 1
- 238000007086 side reaction Methods 0.000 description 1
- 229910001379 sodium hypophosphite Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000003786 synthesis reaction Methods 0.000 description 1
- 229920001169 thermoplastic Polymers 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B25/00—Phosphorus; Compounds thereof
- C01B25/16—Oxyacids of phosphorus; Salts thereof
- C01B25/165—Hypophosphorous acid; Salts thereof
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2002/00—Crystal-structural characteristics
- C01P2002/80—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70
- C01P2002/88—Crystal-structural characteristics defined by measured data other than those specified in group C01P2002/70 by thermal analysis data, e.g. TGA, DTA, DSC
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/32—Thermal properties
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/60—Optical properties, e.g. expressed in CIELAB-values
- C01P2006/65—Chroma (C*)
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
The invention discloses a preparation method of aluminum hypophosphite, which belongs to the technical field of preparation of flame retardants, and comprises the following steps: preparing aluminum sulfate solution, preparing aluminum hydroxide sol, reacting and post-treating; the reaction is carried out, the temperature of a reactor filled with aluminum sulfate solution is controlled to be 85-95 ℃, stirring is carried out, sodium hypophosphite monohydrate is slowly added, simultaneously aluminum hydroxide sol is dropwise added, stirring is continued after the dropwise addition of the aluminum hydroxide sol is finished, concentrated sulfuric acid solution is dropwise added, stirring is continued after the dropwise addition is finished, sodium hypophosphite monohydrate solution is dropwise added, stirring is continued after the dropwise addition is finished, and filtering is carried out, wherein the obtained filter residue is aluminum hypophosphite crude product; the invention can improve the content, whiteness and thermal decomposition temperature of aluminum hypophosphite, reduce the particle size of aluminum hypophosphite, and improve the yield and the uniformity of particle size distribution of aluminum hypophosphite.
Description
Technical Field
The invention relates to the technical field of preparation of flame retardants, in particular to a preparation method of aluminum hypophosphite.
Background
Aluminum hypophosphite is a white crystal or powder, slightly soluble in water, weakly acidic in water, highly hygroscopic, and capable of absorbing moisture in the environment, and therefore is often used as a hygroscopic agent and a desiccant. In addition, the aluminum hypophosphite has better chemical stability and high-temperature stability, can keep stable properties under high temperature and acidic environment, does not cause decomposition of the polymer in processing, does not affect the plastic molding composition, is not volatilized under the normal conditions of preparing and processing thermoplastic polymers, has higher flame retardance, and has better mechanical property and weather resistance in the processing process.
The aluminum hypophosphite is mainly synthesized through double decomposition reaction, specifically, sodium hypophosphite and aluminum sulfate or aluminum chloride are adopted for reaction, then an aluminum hypophosphite wet product is produced through centrifugation or filter pressing, and the aluminum hypophosphite wet product is dried at a high temperature to prepare an aluminum hypophosphite finished product; however, in the double decomposition reaction process, sodium sulfate, sodium chloride and little phosphine are generated in addition to aluminum hypophosphite, the content, whiteness and thermal decomposition temperature of aluminum hypophosphite can be greatly reduced due to the existence of the impurities, the particle diameter of the produced aluminum hypophosphite is too large, and the dispersion is uneven in the use process of downstream customers, so that the flame retardant effect is affected.
In order to solve the problems, the most commonly used method at present is to add sodium hypochlorite in double decomposition to remove phosphine generated, wash and grind wet aluminum hypophosphite, wherein the washing can remove sodium sulfate and sodium chloride, and the grinding can reduce the particle size of the prepared aluminum hypophosphite; however, this method has the following problems: firstly, sodium hypochlorite reacts with aluminum sulfate or aluminum chloride to reduce the yield and content of aluminum hypophosphite; secondly, when sodium hypochlorite reacts with phosphine, heat is released, so that the temperature distribution in the production of aluminum hypophosphite is uneven, the particle size distribution of the prepared aluminum hypophosphite is uneven, and although grinding is helpful for reducing the particle size, the problem of uneven particle size distribution cannot be thoroughly solved.
Chinese patent CN113979412B discloses a synthesis method of aluminum hypophosphite flame retardant with fine particle size and low cost, which is different from the above method, in the synthesis process, aluminum hydroxide, sulfuric acid and sodium hypophosphite monohydrate are adopted as main raw materials, the exothermic principle of acid-base reaction is utilized to rapidly obtain high quality aluminum sulfate solution, and the aluminum hypophosphite product with fine particle size and high quality is obtained through regulating and controlling the proportion of each raw material and the reaction conditions, but the following problems exist: firstly, although the effects of reducing the particle size and improving the uniformity of the particle size distribution can be achieved to a certain extent, the effects are not obvious, the D98 particle size of the prepared aluminum hypophosphite is still more than 20 mu m, and when the aluminum hypophosphite is applied to some fields with higher requirements on the particle size, further grinding is needed; secondly, aluminum hydroxide is insoluble in water and is difficult to uniformly disperse in deionized water, and when the aluminum hydroxide is neutralized and released with sulfuric acid, heat can be locally concentrated, so that the aluminum hydroxide is heated and decomposed into aluminum oxide, and the content and flame retardant effect of the prepared aluminum hypophosphite can be affected by the existence of the aluminum oxide.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides the preparation method of the aluminum hypophosphite, which can improve the yield and the uniformity of the particle size distribution of the aluminum hypophosphite while improving the content, whiteness and thermal decomposition temperature of the aluminum hypophosphite and reducing the particle size of the aluminum hypophosphite.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the preparation method of the aluminum hypophosphite comprises the following steps: preparing aluminum sulfate solution, preparing aluminum hydroxide sol, reacting and post-treating;
the preparation of aluminum sulfate solution, grinding aluminum sulfate to a particle size of 400-600 meshes to obtain grinded aluminum sulfate; adding deionized water and ground aluminum sulfate into a reactor, controlling the temperature of the reactor to 40-45 ℃, controlling the stirring speed to 200-300rpm, and stirring for 50-60min to obtain an aluminum sulfate solution;
in the preparation of the aluminum sulfate solution, the mass ratio of deionized water to the ground aluminum sulfate is 180-200:9-10;
adding aluminum chloride hexahydrate and a first part of deionized water into a reactor, controlling the temperature of the reactor to 20-35 ℃, controlling the stirring speed to 400-500rpm, stirring for 30-40min, dropwise adding ammonia water, continuing stirring for 50-60min after the dropwise adding is finished, filtering, washing filter residues with deionized water with the mass of 5-6 times of the filter residues for 3-4 times, adding filter residues and a second part of deionized water into the reactor, controlling the temperature of the reactor to 80-90 ℃, controlling the stirring speed to 400-500rpm, and stirring for 22-25h to obtain the aluminum hydroxide sol;
in the preparation of the aluminum hydroxide sol, the mass ratio of the aluminum chloride hexahydrate to the first deionized water to the ammonia water to the second deionized water is 7.3-7.5:70-72:38-40:80-85;
the mass fraction of the ammonia water is 15-16%;
the dropping speed of the ammonia water is 2-2.5g/min;
the reaction is carried out, the temperature of a reactor filled with aluminum sulfate solution is controlled to be 85-95 ℃, the stirring speed is controlled to be 200-300rpm, sodium hypophosphite monohydrate is slowly added, aluminum hydroxide sol is dropwise added at the same time, stirring is continued for 3.5-4h after the aluminum hydroxide sol is dropwise added, concentrated sulfuric acid solution is dropwise added, stirring is continued for 50-60min after the dropwise addition is completed, sodium hypophosphite monohydrate solution is dropwise added, stirring is continued for 50-60min after the dropwise addition is completed, and filtering is carried out, wherein the obtained filter residue is aluminum hypophosphite crude product;
the mass ratio of the ground aluminum sulfate in the aluminum sulfate solution to the aluminum chloride hexahydrate in the aluminum hydroxide sol to the sodium hypophosphite monohydrate, the concentrated sulfuric acid solution and the sodium hypophosphite monohydrate solution in the reaction is 9-10:7.3-7.5:18-20:16-18:67-68;
in the reaction, the adding speed of the sodium hypophosphite monohydrate is 2-2.5g/min;
the dropping speed of the aluminum hydroxide sol is 8-9g/min;
the mass fraction of the concentrated sulfuric acid solution is 97.5-98.5%;
the dropping speed of the concentrated sulfuric acid solution is 1.5-2g/min;
the dropping speed of the sodium hypophosphite monohydrate solution is 4-5g/min;
the preparation method of the sodium hypophosphite monohydrate solution comprises the steps of adding sodium hypophosphite monohydrate, deionized water and absolute ethyl alcohol into a reactor, controlling the temperature of the reactor to be 85-95 ℃, controlling the stirring speed to be 300-400rpm, and stirring for 40-60min to obtain the sodium hypophosphite monohydrate solution;
in the preparation of the sodium hypophosphite monohydrate solution, the mass ratio of the sodium hypophosphite monohydrate to deionized water to absolute ethyl alcohol is 50-51:12-13:1.4-1.5;
and (3) after-treatment, cleaning the aluminum hypophosphite crude product by deionized water with the mass of 3-4 times of the aluminum hypophosphite crude product for 2-3 times, and drying at 200-220 ℃ to obtain the aluminum hypophosphite product.
Compared with the prior art, the invention has the beneficial effects that:
(1) The preparation method of the aluminum hypophosphite can improve the content of the aluminum hypophosphite to 97.69-98.64%;
(2) The preparation method of the aluminum hypophosphite can improve the whiteness of the aluminum hypophosphite to 96.7-97.4%;
(3) According to the preparation method of the aluminum hypophosphite, the thermal decomposition temperature of the aluminum hypophosphite can be increased, and the 1% thermal decomposition temperature of the aluminum hypophosphite is increased to 333.5-359.8 ℃;
(4) According to the preparation method of the aluminum hypophosphite, the particle size of the aluminum hypophosphite can be reduced, the uniformity of the particle size distribution of the aluminum hypophosphite can be improved, and the D97 particle size of the aluminum hypophosphite is reduced to 3.460-5.366 mu m;
(5) The preparation method of the aluminum hypophosphite can improve the yield of the aluminum hypophosphite and improve the molar yield of the aluminum hypophosphite to 97.1-98.8%.
Drawings
FIG. 1 is a thermogravimetric plot of the aluminum hypophosphite product prepared in example 1;
in the figure, 1-DTA curve, 2-TG curve;
FIG. 2 is a graph of the particle size analysis of the aluminum hypophosphite product prepared in example 1;
in the figure, 1-interval distribution curve, 2-cumulative distribution curve;
FIG. 3 is a thermogravimetric plot of the aluminum hypophosphite product prepared in example 2;
in the figure, 1-DTA curve, 2-TG curve;
FIG. 4 is a graph of the particle size analysis of the aluminum hypophosphite product prepared in example 2;
in the figure, 1-interval distribution curve, 2-cumulative distribution curve;
FIG. 5 is a thermogravimetric plot of the aluminum hypophosphite product prepared in example 3;
in the figure, 1-DTA curve, 2-TG curve;
FIG. 6 is a graph of the particle size analysis of the aluminum hypophosphite product prepared in example 3;
in the figure, 1-interval distribution curve, 2-cumulative distribution curve;
FIG. 7 is a thermogravimetric plot of the aluminum hypophosphite product prepared in example 4;
in the figure, 1-DTA curve, 2-TG curve;
FIG. 8 is a graph of the particle size analysis of the aluminum hypophosphite product prepared in example 4;
in the figure, 1-interval distribution curve, 2-cumulative distribution curve.
Detailed Description
Specific embodiments of the present invention will now be described in order to provide a clearer understanding of the technical features, objects and effects of the present invention.
Example 1
The preparation method of the aluminum hypophosphite specifically comprises the following steps:
1. preparing an aluminum sulfate solution: grinding aluminum sulfate to a particle size of 400 meshes to obtain ground aluminum sulfate; 180g of deionized water and 9g of ground aluminum sulfate are added into a reactor, the temperature of the reactor is controlled to 40 ℃, the stirring speed is controlled to 200rpm, and the mixture is stirred for 50min to obtain an aluminum sulfate solution;
2. preparing aluminum hydroxide sol: adding 7.3g of aluminum chloride hexahydrate and 70g of deionized water into a reactor, controlling the temperature of the reactor to 20 ℃, controlling the stirring speed to 400rpm, stirring for 30min, dripping 38g of 15% ammonia water by mass fraction, controlling the dripping speed to 2g/min, continuing stirring for 50min after dripping, filtering, washing filter residues with deionized water with the mass of 5 times of filter residues for 3 times, adding filter residues and 80g of deionized water into the reactor, controlling the temperature of the reactor to 80 ℃, controlling the stirring speed to 400rpm, and stirring for 22h to obtain aluminum hydroxide sol;
3. the reaction: controlling the temperature of a reactor filled with aluminum sulfate solution to 85 ℃, controlling the stirring speed to 200rpm, slowly adding 18g of sodium hypophosphite monohydrate, controlling the adding speed to 2g/min, simultaneously dropwise adding aluminum hydroxide sol, controlling the dropping speed to 8g/min, continuously stirring for 3.5h when the dropwise adding of the aluminum hydroxide sol is finished, dropwise adding 16g of concentrated sulfuric acid solution with the mass fraction of 97.5%, controlling the dropping speed to 1.5g/min, continuously stirring for 50min after the dropwise adding is finished, dropwise adding 67g of sodium hypophosphite monohydrate solution, controlling the dropping speed to 4g/min, continuously stirring for 50min after the dropwise adding is finished, and filtering to obtain filter residues which are aluminum hypophosphite crude products;
the preparation method of the sodium hypophosphite monohydrate solution comprises the following steps: adding 50g of sodium hypophosphite monohydrate, 12g of deionized water and 1.4g of absolute ethyl alcohol into a reactor, controlling the temperature of the reactor to 85 ℃, controlling the stirring speed to 300rpm, and stirring for 40min to obtain sodium hypophosphite monohydrate solution;
4. post-treatment: washing the aluminum hypophosphite crude product with deionized water with the mass of 3 times of the aluminum hypophosphite crude product for 2 times, and then drying at 200 ℃ to obtain 12.6g of aluminum hypophosphite product, wherein the moisture content of the aluminum hypophosphite product is 0.23%, the aluminum hypophosphite content is 98.51%, the whiteness is 96.7%, and the aluminum hypophosphite product is subjected to thermogravimetric curve analysis, the obtained thermogravimetric curve is shown in figure 1, and as can be seen from figure 1, the 1% thermal decomposition temperature of the aluminum hypophosphite product is 359.1 ℃; the particle size analysis of the aluminum hypophosphite product is carried out, the obtained particle size analysis chart is shown in figure 2, and as can be seen from figure 2, the D97 particle size of the aluminum hypophosphite product is 4.359 mu m, the particle size is 0.02% in the range of 0.1-0.2 mu m, the particle size is 31.97% in the range of 0.2-0.5 mu m, the particle size is 37.01% in the range of 0.5-1 mu m, the particle size is 18.73% in the range of 1-2 mu m, the particle size is 10.32% in the range of 2-5 mu m, and the particle size is 1.95% in the range of 5-10 mu m;
the molar yield was calculated based on the molar amount of aluminum ions added, and the molar yield of aluminum hypophosphite was calculated to be 98.8%.
Example 2
The preparation method of the aluminum hypophosphite specifically comprises the following steps:
1. preparing an aluminum sulfate solution: grinding aluminum sulfate to a particle size of 500 meshes to obtain ground aluminum sulfate; 185g of deionized water and 9.2g of ground aluminum sulfate are added into a reactor, the temperature of the reactor is controlled to be 42 ℃, the stirring speed is controlled to be 220rpm, and the mixture is stirred for 52 minutes to obtain an aluminum sulfate solution;
2. preparing aluminum hydroxide sol: adding 7.3g of aluminum chloride hexahydrate and 71g of deionized water into a reactor, controlling the temperature of the reactor to 25 ℃, controlling the stirring speed to 450rpm, stirring for 35min, dripping 39g of ammonia water with the mass fraction of 15.2%, controlling the dripping speed to 2.1g/min, continuing stirring for 52min after dripping, filtering, washing filter residues with deionized water with the mass of 5 times of filter residues for 3 times, adding filter residues and 82g of deionized water into the reactor, controlling the temperature of the reactor to 85 ℃, controlling the stirring speed to 450rpm, and stirring for 23h to obtain aluminum hydroxide sol;
3. the reaction: controlling the temperature of a reactor filled with aluminum sulfate solution to 90 ℃, controlling the stirring speed to 250rpm, slowly adding 19g of sodium hypophosphite monohydrate, controlling the adding speed to 2.2g/min, simultaneously dropwise adding aluminum hydroxide sol, controlling the dropping speed to 8.5g/min, continuously stirring for 3.8 hours after the dropping of the aluminum hydroxide sol is finished, continuously stirring for 52 minutes after the dropping is finished, dropwise adding 67.2g of sodium hypophosphite monohydrate solution, controlling the dropping speed to 4.2g/min, continuously stirring for 52 minutes after the dropping is finished, and filtering to obtain filter residues which are aluminum hypophosphite crude products;
the preparation method of the sodium hypophosphite monohydrate solution comprises the following steps: adding 50.4g of sodium hypophosphite monohydrate, 12.2g of deionized water and 1.4g of absolute ethyl alcohol into a reactor, controlling the temperature of the reactor to 90 ℃, controlling the stirring speed to 350rpm, and stirring for 45min to obtain sodium hypophosphite monohydrate solution;
4. post-treatment: washing the aluminum hypophosphite crude product with deionized water 3 times the mass of the aluminum hypophosphite crude product for 3 times, and then drying at 210 ℃ to obtain 12.7g of aluminum hypophosphite product, wherein the moisture content of the aluminum hypophosphite product is 0.18%, the aluminum hypophosphite content is 98.64%, the whiteness is 97.3%, and the aluminum hypophosphite product is subjected to thermogravimetric curve analysis, the obtained thermogravimetric curve is shown in figure 3, and as can be seen from figure 3, the 1% thermal decomposition temperature of the aluminum hypophosphite product is 359.8 ℃; the particle size analysis of the aluminum hypophosphite product is carried out, the obtained particle size analysis chart is shown in figure 4, and as can be seen from figure 4, the D97 particle size of the aluminum hypophosphite product is 3.460 mu m, the particle size is 0.02% in the range of 0.1-0.2 mu m, the particle size is 31.36% in the range of 0.2-0.5 mu m, the particle size is 39.10% in the range of 0.5-1 mu m, the particle size is 20.23% in the range of 1-2 mu m, the particle size is 8.49% in the range of 2-5 mu m, and the particle size is 0.8% in the range of 5-10 mu m;
the molar yield was calculated based on the molar amount of aluminum ions added, and the molar yield of aluminum hypophosphite was calculated to be 98.7%.
Example 3
The preparation method of the aluminum hypophosphite specifically comprises the following steps:
1. preparing an aluminum sulfate solution: grinding aluminum sulfate to a particle size of 500 meshes to obtain ground aluminum sulfate; adding 195g of deionized water and 9.8g of ground aluminum sulfate into a reactor, controlling the temperature of the reactor to 43 ℃, controlling the stirring speed to 280rpm, and stirring for 58min to obtain an aluminum sulfate solution;
2. preparing aluminum hydroxide sol: adding 7.4g of aluminum chloride hexahydrate and 71.5g of deionized water into a reactor, controlling the temperature of the reactor to 30 ℃, controlling the stirring speed to 480rpm, stirring for 38min, dripping 39.5g of 15.5 mass percent ammonia water, controlling the dripping speed to 2.4g/min, continuing stirring for 58min after dripping is finished, filtering, washing filter residues with deionized water with the mass of 6 times of filter residues for 4 times, adding filter residues and 84g of deionized water into the reactor, controlling the temperature of the reactor to 88 ℃, controlling the stirring speed to 480rpm, and stirring for 24h to obtain aluminum hydroxide sol;
3. the reaction: controlling the temperature of a reactor filled with aluminum sulfate solution to 92 ℃, controlling the stirring speed to 280rpm, slowly adding 19.5g of sodium hypophosphite monohydrate, controlling the adding speed to 2.4g/min, simultaneously dropwise adding aluminum hydroxide sol, controlling the dropping speed to 8.8g/min, continuously stirring for 4 hours after the dropping of the aluminum hydroxide sol is finished, dropwise adding 17.5g of concentrated sulfuric acid solution with the mass fraction of 98.2%, controlling the dropping speed to 1.8g/min, continuously stirring for 58 minutes after the dropping is finished, dropwise adding 67.8g of sodium hypophosphite monohydrate solution, controlling the dropping speed to 4.7g/min, continuously stirring for 58 minutes after the dropping is finished, and filtering to obtain filter residues which are crude aluminum hypophosphite;
the preparation method of the sodium hypophosphite monohydrate solution comprises the following steps: adding 50.8g of sodium hypophosphite monohydrate, 12.8g of deionized water and 1.5g of absolute ethyl alcohol into a reactor, controlling the temperature of the reactor to 92 ℃, controlling the stirring speed to 380rpm, and stirring for 55min to obtain sodium hypophosphite monohydrate solution;
4. post-treatment: washing the aluminum hypophosphite crude product with deionized water with the mass of 4 times of the aluminum hypophosphite crude product for 3 times, and then drying at 210 ℃ to obtain 13.2g of aluminum hypophosphite product, wherein the moisture content of the aluminum hypophosphite product is 0.16%, the aluminum hypophosphite content is 98.39%, the whiteness is 97.4%, and the aluminum hypophosphite product is subjected to thermogravimetric curve analysis, so that a thermogravimetric curve is shown in FIG. 5, and as can be seen from FIG. 5, the 1% thermal decomposition temperature of the aluminum hypophosphite product is 359.3 ℃; the particle size analysis of the aluminum hypophosphite product is carried out, the obtained particle size analysis chart is shown in figure 6, and as can be seen from figure 6, the D97 particle size of the aluminum hypophosphite product is 4.332 mu m, the particle size is 0.01% in the range of 0.1-0.2 mu m, the particle size is 23.52% in the range of 0.2-0.5 mu m, the particle size is 41.70% in the range of 0.5-1 mu m, the particle size is 24.64% in the range of 1-2 mu m, the particle size is 7.51% in the range of 2-5 mu m, the particle size is 2.41% in the range of 5-10 mu m, and the particle size is 0.21% in the range of 10-20 mu m;
the molar yield was calculated based on the molar amount of aluminum ions added, and the molar yield of aluminum hypophosphite was calculated to be 98.5%.
Example 4
The preparation method of the aluminum hypophosphite specifically comprises the following steps:
1. preparing an aluminum sulfate solution: grinding aluminum sulfate to 600 meshes to obtain ground aluminum sulfate; 200g of deionized water and 10g of ground aluminum sulfate are added into a reactor, the temperature of the reactor is controlled to 45 ℃, the stirring speed is controlled to 300rpm, and the mixture is stirred for 60min to obtain an aluminum sulfate solution;
2. preparing aluminum hydroxide sol: adding 7.5g of aluminum chloride hexahydrate and 72g of deionized water into a reactor, controlling the temperature of the reactor to 35 ℃, controlling the stirring speed to 500rpm, stirring for 40min, dripping 40g of 16% ammonia water, controlling the dripping speed to 2.5g/min, continuing stirring for 60min after dripping, filtering, washing filter residues with deionized water with the mass of 6 times of filter residues for 4 times, adding filter residues and 85g of deionized water into the reactor, controlling the temperature of the reactor to 90 ℃, controlling the stirring speed to 500rpm, and stirring for 25h to obtain aluminum hydroxide sol;
3. the reaction: controlling the temperature of a reactor filled with aluminum sulfate solution to 95 ℃, controlling the stirring speed to 300rpm, slowly adding 20g of sodium hypophosphite monohydrate, controlling the adding speed to 2.5g/min, simultaneously dropwise adding aluminum hydroxide sol, controlling the dropping speed to 9g/min, continuously stirring for 4 hours after the dropwise adding of the aluminum hydroxide sol is finished, dropwise adding 18g of 98.5% concentrated sulfuric acid solution with the mass fraction, controlling the dropping speed to 2g/min, continuously stirring for 60 minutes after the dropwise adding is finished, dropwise adding 68g of sodium hypophosphite monohydrate solution, controlling the dropping speed to 5g/min, continuously stirring for 60 minutes after the dropwise adding is finished, and filtering to obtain filter residues which are aluminum hypophosphite crude products;
the preparation method of the sodium hypophosphite monohydrate solution comprises the following steps: 51g of sodium hypophosphite monohydrate, 13g of deionized water and 1.5g of absolute ethyl alcohol are added into a reactor, the temperature of the reactor is controlled to 95 ℃, the stirring speed is controlled to 400rpm, and the mixture is stirred for 60 minutes to obtain sodium hypophosphite monohydrate solution;
4. post-treatment: washing the aluminum hypophosphite crude product with deionized water with the mass of 4 times of the aluminum hypophosphite crude product for 3 times, and then drying at 220 ℃ to obtain 13.3g of aluminum hypophosphite product, wherein the moisture content of the aluminum hypophosphite product is 0.12%, the aluminum hypophosphite content is 97.69%, the whiteness is 96.8%, and the aluminum hypophosphite product is subjected to thermogravimetric curve analysis, the obtained thermogravimetric curve is shown in figure 7, and as can be seen from figure 7, the 1% thermal decomposition temperature of the aluminum hypophosphite product is 333.5 ℃; the particle size analysis of the aluminum hypophosphite product is carried out, the obtained particle size analysis chart is shown in figure 8, and as can be seen from figure 8, the D97 particle size of the aluminum hypophosphite product is 5.366 mu m, the particle size is 0.01% in the range of 0.1-0.2 mu m, the particle size is 21.34% in the range of 0.2-0.5 mu m, the particle size is 38.03% in the range of 0.5-1 mu m, the particle size is 26.81% in the range of 1-2 mu m, the particle size is 10.54% in the range of 2-5 mu m, the particle size is 3.05% in the range of 5-10 mu m, and the particle size is 0.22% in the range of 10-20 mu m;
the molar yield was calculated based on the molar amount of aluminum ions added, and the molar yield of aluminum hypophosphite was calculated to be 97.1%.
Comparative example 1
The preparation method of aluminum hypophosphite described in example 2 was used, which was different in that: omitting step 2 to prepare aluminum hydroxide sol, omitting the addition of aluminum hydroxide sol and concentrated sulfuric acid in step 3 of double decomposition reaction, and omitting the addition of 67.2g of sodium hypophosphite monohydrate solution; the reaction in the step 3 is changed into:
controlling the temperature of a reactor filled with aluminum sulfate solution to 90 ℃, controlling the stirring speed to 250rpm, slowly adding 19g of sodium hypophosphite monohydrate, controlling the adding speed to 2.2g/min, continuing stirring for 3.8h when the adding of the sodium hypophosphite monohydrate is finished, and filtering to obtain filter residues which are crude aluminum hypophosphite;
according to the method of the 4 th post-treatment, 3 times of deionized water with the mass of the aluminum hypophosphite crude product is used for cleaning the aluminum hypophosphite crude product for 3 times, and then the aluminum hypophosphite crude product is dried at 210 ℃ to obtain 5.5g of aluminum hypophosphite product, wherein the moisture content of the aluminum hypophosphite product is 0.21%, the aluminum hypophosphite content is 96.84%, the whiteness is 93.7%, the 1% thermal decomposition temperature is 327.2 ℃, the D97 particle size is 10.852 mu m, the particle size is 10.18% in the range of 0.2-0.5 mu m, the particle size is 18.14% in the range of 0.5-1 mu m, the particle size is 28.37% in the range of 1-2 mu m, the particle size is 23.76% in the range of 2-5 mu m, the particle size is 14.54% in the range of 5-10 mu m, and the particle size is 5.01% in the range of 10-20 mu m;
the molar yield was calculated based on the molar amount of aluminum ions added, and the molar yield of aluminum hypophosphite was calculated to be 89.2%.
From the above results, it can be seen that the aluminum hypophosphite prepared in examples 1-4 has higher content, whiteness and yield than those of comparative example 1, and the aluminum hypophosphite prepared in examples 1-4 has smaller particle size and higher uniformity of particle size distribution;
according to analysis, in the reaction process of aluminum sulfate and sodium hypophosphite monohydrate, the particle size of the formed aluminum hypophosphite can be controlled by adding aluminum hydroxide sol, the particle size of the aluminum hypophosphite is reduced, the uniformity of the particle size distribution of the aluminum hypophosphite is improved, after the reaction of the aluminum sulfate and sodium hypophosphite monohydrate is finished, sulfuric acid is added to prepare aluminum hydroxide sol into small-particle-size aluminum sulfate, and the small-particle-size aluminum sulfate further reacts with sodium hypophosphite monohydrate in a sodium hypophosphite monohydrate solution added later to obtain small-particle-size aluminum hypophosphite, so that the particle size and the particle size uniformity of the prepared aluminum hypophosphite are reduced;
through further analysis, the addition of the aluminum hydroxide sol is also favorable for the full reaction of aluminum sulfate and sodium hypophosphite monohydrate, and avoids the occurrence of side reaction and the generation of impurities, so that the yield and purity of the prepared aluminum hypophosphite are improved, meanwhile, the aluminum hydroxide sol can absorb the formed phosphine, and the influence of the additional addition of sodium hypochlorite on the purity of the aluminum hypophosphite is avoided, so that the influence of impurities on the thermal decomposition temperature of the aluminum hypophosphite is avoided, and the thermal decomposition temperature of the aluminum hypophosphite is improved.
The percentages used in the present invention are mass percentages unless otherwise indicated.
Finally, it should be noted that: the foregoing description is only a preferred embodiment of the present invention, and the present invention is not limited thereto, but it is to be understood that modifications and equivalents of some of the technical features described in the foregoing embodiments may be made by those skilled in the art, although the present invention has been described in detail with reference to the foregoing embodiments. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (5)
1. The preparation method of the aluminum hypophosphite is characterized by comprising the following steps of: preparing aluminum sulfate solution, preparing aluminum hydroxide sol, reacting and post-treating;
grinding aluminum sulfate to obtain ground aluminum sulfate; adding deionized water and ground aluminum sulfate into a reactor, controlling the temperature of the reactor to 40-45 ℃, and stirring to obtain an aluminum sulfate solution;
adding aluminum chloride hexahydrate and a first part of deionized water into a reactor, controlling the temperature of the reactor to be 20-35 ℃, stirring, dropwise adding ammonia water, continuously stirring after the dropwise adding is finished, filtering, cleaning filter residues, adding the filter residues and a second part of deionized water into the reactor, controlling the temperature of the reactor to be 80-90 ℃, and stirring to obtain aluminum hydroxide sol;
in the preparation of the aluminum hydroxide sol, the mass ratio of the aluminum chloride hexahydrate to the first deionized water to the ammonia water to the second deionized water is 7.3-7.5:70-72:38-40:80-85;
the mass fraction of the ammonia water is 15-16%;
the dropping speed of the ammonia water is 2-2.5g/min;
the reaction is carried out, the temperature of a reactor filled with aluminum sulfate solution is controlled to be 85-95 ℃, stirring is carried out, sodium hypophosphite monohydrate is slowly added, simultaneously aluminum hydroxide sol is dropwise added, stirring is continued after the dropwise addition of the aluminum hydroxide sol is finished, concentrated sulfuric acid solution is dropwise added, stirring is continued after the dropwise addition is finished, sodium hypophosphite monohydrate solution is dropwise added, stirring is continued after the dropwise addition is finished, and filtering is carried out, wherein the obtained filter residue is aluminum hypophosphite crude product;
the mass ratio of the ground aluminum sulfate in the aluminum sulfate solution to the aluminum chloride hexahydrate in the aluminum hydroxide sol to the sodium hypophosphite monohydrate, the concentrated sulfuric acid solution and the sodium hypophosphite monohydrate solution in the reaction is 9-10:7.3-7.5:18-20:16-18:67-68;
in the reaction, the adding speed of the sodium hypophosphite monohydrate is 2-2.5g/min;
the dropping speed of the aluminum hydroxide sol is 8-9g/min;
the mass fraction of the concentrated sulfuric acid solution is 97.5-98.5%;
the dropping speed of the concentrated sulfuric acid solution is 1.5-2g/min;
the dropping speed of the sodium hypophosphite monohydrate solution is 4-5g/min.
2. The method for preparing aluminum hypophosphite according to claim 1, wherein in the preparation of aluminum sulfate solution, the mass ratio of deionized water to ground aluminum sulfate is 180-200:9-10.
3. The method for preparing aluminum hypophosphite according to claim 1, wherein the method for preparing the sodium hypophosphite monohydrate solution comprises the steps of adding sodium hypophosphite monohydrate, deionized water and absolute ethyl alcohol into a reactor, controlling the temperature of the reactor to 85-95 ℃, and stirring to obtain the sodium hypophosphite monohydrate solution.
4. The method for preparing aluminum hypophosphite according to claim 3, wherein in the preparation of the sodium hypophosphite monohydrate solution, the mass ratio of sodium hypophosphite monohydrate, deionized water and absolute ethyl alcohol is 50-51:12-13:1.4-1.5.
5. The method for preparing aluminum hypophosphite according to claim 1, wherein the post-treatment is carried out, and the aluminum hypophosphite product is obtained by washing and drying the crude aluminum hypophosphite product.
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005060173A (en) * | 2003-08-13 | 2005-03-10 | Mitsubishi Chemicals Corp | Method of producing aluminophosphates |
| KR20100012345A (en) * | 2008-07-28 | 2010-02-08 | 순천대학교 산학협력단 | Aluminum hydroxide particle improving for fire-retardant and production method thereof |
| CN103496681A (en) * | 2013-10-18 | 2014-01-08 | 上海美莱珀化工材料科技有限公司 | Method for preparing aluminum hypophosphite |
| CN113979412A (en) * | 2021-10-29 | 2022-01-28 | 湖北航天化学技术研究所 | Synthesis method of fine-particle-size low-cost aluminum hypophosphite flame retardant |
| CN114752105A (en) * | 2022-04-18 | 2022-07-15 | 深圳市锦昊辉实业发展有限公司 | Preparation method of flame-retardant material |
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| EP2475743A4 (en) * | 2009-08-24 | 2014-01-29 | Rhodia China Co Ltd | A process for stabilizing hypophosphite salts |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005060173A (en) * | 2003-08-13 | 2005-03-10 | Mitsubishi Chemicals Corp | Method of producing aluminophosphates |
| KR20100012345A (en) * | 2008-07-28 | 2010-02-08 | 순천대학교 산학협력단 | Aluminum hydroxide particle improving for fire-retardant and production method thereof |
| CN103496681A (en) * | 2013-10-18 | 2014-01-08 | 上海美莱珀化工材料科技有限公司 | Method for preparing aluminum hypophosphite |
| CN113979412A (en) * | 2021-10-29 | 2022-01-28 | 湖北航天化学技术研究所 | Synthesis method of fine-particle-size low-cost aluminum hypophosphite flame retardant |
| CN114752105A (en) * | 2022-04-18 | 2022-07-15 | 深圳市锦昊辉实业发展有限公司 | Preparation method of flame-retardant material |
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