WO2023019746A1 - 一种低成本的镁铝水滑石制备方法 - Google Patents

一种低成本的镁铝水滑石制备方法 Download PDF

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WO2023019746A1
WO2023019746A1 PCT/CN2021/128334 CN2021128334W WO2023019746A1 WO 2023019746 A1 WO2023019746 A1 WO 2023019746A1 CN 2021128334 W CN2021128334 W CN 2021128334W WO 2023019746 A1 WO2023019746 A1 WO 2023019746A1
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magnesium
aluminum hydrotalcite
sodium
solution
magnesium aluminum
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PCT/CN2021/128334
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English (en)
French (fr)
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曾维兴
曹例祥
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湖南恒光化工有限公司
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    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D5/00—Sulfates or sulfites of sodium, potassium or alkali metals in general
    • C01D5/14—Preparation of sulfites
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P20/00—Technologies relating to chemical industry
    • Y02P20/50—Improvements relating to the production of bulk chemicals
    • Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts

Definitions

  • the invention relates to the technical field of magnesium aluminum hydrotalcite preparation, in particular to a low-cost preparation method of magnesium aluminum hydrotalcite.
  • Magnesium aluminum hydrotalcite or Mg/Al-LDHs is a functional material, which can be used in the field of preparation of flame retardant materials as a flame retardant, and can be used in the plastic heat stabilizer industry as an acid absorber.
  • the molecular formula of magnesium aluminum hydrotalcite can be expressed as 4Mg2Al(OH)12CO3 ⁇ 4H2O.
  • the raw materials for the initial preparation of magnesium aluminum hydrotalcite usually include magnesium chloride or magnesium sulfate, aluminum chloride, sodium hydroxide, and sodium carbonate.
  • the process principle is as follows:
  • Sodium sulfite is a basic chemical raw material.
  • sodium carbonate or sodium hydroxide is usually used to absorb and purify sulfur dioxide gas to form sodium sulfite products.
  • the production cost of sodium sulfite mainly lies in sodium carbonate or sodium hydroxide.
  • the cost of raw materials, and the preparation process of magnesium aluminum hydrotalcite just needs sodium carbonate and sodium hydroxide. Therefore, if sodium carbonate and sodium hydroxide are used as raw materials to realize the co-production of magnesium aluminum hydrotalcite and sodium sulfite, it can effectively solve the production problem.
  • the purpose of the present invention is to provide a low-cost magnesium aluminum hydrotalcite preparation method, which can reduce the production cost and reduce the generation of waste water through the form of co-production with sodium sulfite products.
  • a kind of low-cost magnesium aluminum hydrotalcite preparation method it comprises the following steps:
  • Step 1 Take bittern ore as raw material, add it into a reaction kettle and mix it with an appropriate amount of water, then feed sulfur dioxide gas to form a soluble magnesium bisulfite solution, and filter out insoluble impurities.
  • the main component in bittern ore is magnesium oxide
  • the remaining impurities include aluminum oxide, ferric oxide, and silicon dioxide.
  • the sulfur dioxide gas introduced into the reaction kettle will not react with the components in the impurities, but Only can react with magnesium oxide to generate magnesium bisulfite, therefore, main reaction principle in this step is as follows:
  • the concentration of the magnesium oxide slurry obtained after mixing the bittern ore with an appropriate amount of water in a reactor is controlled within the range of 2-6%.
  • Step 2 adding aluminum hydroxide to the sodium hydroxide solution and heating to dissolve, and adding sodium carbonate to prepare sodium metaaluminate and sodium carbonate solution.
  • Step 3 adding the sodium metaaluminate and sodium carbonate solution configured in step 2 to the magnesium bisulfite solution prepared in step 1, heating and stirring, the obtained reaction slurry is magnesium aluminum hydrotalcite precipitation and sodium sulfite solution,
  • the reaction principle in this step is as follows:
  • Step 4 Filter and wash the reaction slurry obtained in Step 3 to obtain magnesium aluminum hydrotalcite filter cake, sodium sulfite filtrate and washing liquid.
  • Step 5 drying the magnesium aluminum hydrotalcite filter cake to obtain the magnesium aluminum hydrotalcite product; concentrating the sodium sulfite filtrate to obtain the sodium sulfite product.
  • Step 6 the washing liquid obtained in step 4 is sent into the reactor of step 1 to repeatedly prepare magnesium bisulfite solution.
  • the magnesium oxide content in the bittern ore is 90%.
  • the reaction temperature in the reactor in step 1 is 25-65° C.
  • the reaction time is 6-12 hours.
  • the mass concentration of the magnesium bisulfite solution prepared in step one is 6-16%.
  • the mass concentration of sodium hydroxide solution in step 2 is 20-32%.
  • the reaction temperature in step 3 is 85-105° C., and the reaction time is 8-16 hours.
  • the whiteness of the aluminum hydroxide is ⁇ 90%, the effective content is ⁇ 99%, and the particle size is greater than 200 mesh; the volume content of sulfur dioxide in the sulfur dioxide gas is > 8%.
  • the principle of the present invention is: use magnesium oxide, the main component in the raw material of bitter earth ore, to mix sulfur dioxide gas in the reaction kettle to prepare a high-purity magnesium bisulfite solution, and then mix it with sodium metaaluminate and sodium carbonate solution, Reacting with sodium hydroxide can co-produce sodium sulfite while obtaining magnesium aluminum hydrotalcite product.
  • bitter earth ore is used as the raw material, the main component of which is magnesium oxide, which can dissolve and react with sulfur dioxide, and the rest of the impurities do not react, so there is no need to deliberately choose high-purity magnesium hydroxide or magnesium oxide raw materials, and the cost of use is relatively cheap .
  • the present invention uses sulfur dioxide gas as one of the raw materials, which has great application value for sulfur factories. It can make maximum use of the sulfur dioxide gas collected by discharge for production and preparation, and because the magnesium aluminum water is prepared At the same time as the talc product, sodium sulfite can also be co-produced. Therefore, compared with the traditional method for preparing magnesium aluminum hydrotalcite, the method provided by the invention is more suitable for this type of chemical plant, and the actual benefits produced are more significant.
  • the process method provided by the invention can not only prepare magnesium aluminum hydrotalcite after consuming sodium hydroxide raw material Hydrotalcite can also be co-produced to prepare sodium sulfite, so that the application of sodium hydroxide raw material can produce more than expected value. From the perspective of preparing magnesium aluminum hydrotalcite, since it is no longer necessary to consume additional sodium hydroxide raw material, it is quite In a disguised form to reduce production costs.
  • the washing solution obtained by washing magnesium aluminum hydrotalcite precipitation and sodium sulfite solution can be sent back to the initial step for batching to repeatedly prepare magnesium bisulfite solution, so as to achieve resource reuse and basically no waste liquid
  • the resulting process effect is of great significance for industrial production and has a good market prospect.
  • the molar ratio of the above-mentioned magnesium oxide to sulfur dioxide is 1.4.
  • magnesium aluminum hydrotalcite filter cake is solid Filter cake with a content of 48%.
  • the solid content represents the mass percentage of the rest of the magnesium aluminum hydrotalcite slurry after pressure filtration and washing in the total amount.
  • the above filter cake is dried and crushed to obtain the magnesium aluminum hydrotalcite product, and the sodium sulfite filtrate is removed from the MVR to concentrate and crystallize, so that the sodium sulfite product can be obtained, and the above washing liquid is sent into the reaction kettle for batching to repeatedly prepare magnesium bisulfite solution.
  • magnesium aluminum hydrotalcite product was taken as a sample, and the sample was characterized and analyzed by means of X-ray diffraction (XDR), plasma emission spectrum (ICP), transmission electron microscope (TEM) and laser particle size analysis, and the measured The particle size of the sample is between 20-92nm, and the purity is 99.6%, which proves that the product has high crystallinity and meets the performance indicators of magnesium aluminum hydrotalcite prepared by the existing industrial-grade preparation method.
  • XDR X-ray diffraction
  • ICP plasma emission spectrum
  • TEM transmission electron microscope
  • Example 1 The difference between this example and Example 1 is that the reaction conditions of bittern ore and high-concentration sulfur dioxide are 6 hours at 25°C; the molar ratio of magnesium oxide to sulfur dioxide is 1.6; during the preparation of sodium metaaluminate and sodium carbonate solution Heating to 85°C; the magnesium bisulfite solution, sodium aluminate, sodium carbonate, and sodium hydroxide solution are mixed and stirred for reaction, and the reaction condition is to raise the temperature to 85°C and react for 8 hours.
  • Example 1 The difference between this example and Example 1 is that the reaction conditions of bittern ore and high-concentration sulfur dioxide are 12 hours at 65°C; the molar ratio of magnesium oxide to sulfur dioxide is 1.8; during the preparation of sodium metaaluminate and sodium carbonate solution Heating to 105°C; the magnesium bisulfite solution, sodium aluminate, sodium carbonate, and sodium hydroxide solution are mixed and stirred for a reaction condition of heating up to 105°C and reacting for 16 hours.
  • magnesium aluminum hydrotalcite product obtained in the above preparation process Take the appropriate amount of magnesium aluminum hydrotalcite product obtained in the above preparation process as a sample, use the same detection means as in Example 1 to characterize and analyze the sample, and the particle size of the sample is measured between 20-97nm, and the purity is 99.4%. It can be proved that the product has high crystallinity and meets the performance index of the magnesium aluminum hydrotalcite product prepared by the existing industrial-grade preparation method.
  • Example 1 The difference between this example and Example 1 is that the reaction conditions of bittern ore and high-concentration sulfur dioxide are 8 hours at 50°C; the molar ratio of magnesium oxide to sulfur dioxide is 1.2; during the preparation of sodium metaaluminate and sodium carbonate solution Heating to 100°C; the magnesium bisulfite solution, sodium aluminate, sodium carbonate, and sodium hydroxide solution are mixed and stirred for a reaction condition of heating up to 100°C and reacting for 13 hours.
  • magnesium bisulfite solution is prepared by reacting sulfur dioxide gas and magnesium oxide in bittern ore in water, while the other side can be heated and dissolved by adding aluminum hydroxide in sodium hydroxide solution, and adding Sodium carbonate, configure sodium metaaluminate and sodium carbonate solution, then add sodium metaaluminate and sodium carbonate solution to magnesium bisulfite solution, heat up and stir to obtain magnesium aluminum hydrotalcite precipitation and sodium sulfite solution, and then through subsequent Filtration, washing and corresponding drying or concentration treatment can co-produce magnesium aluminum hydrotalcite products and sodium sulfite products.
  • the addition of sulfur dioxide gas can not only cooperate with magnesium oxide to prepare magnesium bisulfite solution, but also achieve the purpose of recovering and treating the tail gas produced by the sulfur production process.
  • the preparation method provided by the invention can not only obtain the magnesium aluminum hydrotalcite after consuming the sodium hydroxide raw material
  • the preparation of magnesium aluminum hydrotalcite can also be co-produced to prepare sodium sulfite, which makes the application of sodium hydroxide raw materials produce more than expected value. From the perspective of preparing magnesium aluminum hydrotalcite, it is no longer necessary to consume additional sodium hydroxide Raw materials, so it is equivalent to reducing the production cost in a disguised form.
  • magnesium oxide slurry concentration is controlled in the scope of 2-6%, and the mass concentration of magnesium bisulfite solution can be prepared to reach 6-6%. 16%, and then it can be calculated by formula (4), the magnesium bisulfite within this mass concentration range will have a lower proportion in the reaction system than sodium metaaluminate, sodium carbonate solution, and sodium hydroxide solution, then Correspondingly, the appropriate use of relatively more mass concentration of reactants (sodium metaaluminate and sodium carbonate solution, sodium hydroxide solution) can increase the conversion rate of magnesium bisulfite raw materials, thereby fully utilizing magnesium bisulfite raw materials ,reduce manufacturing cost.
  • the final product only includes a certain amount of aqueous solution except for magnesium aluminum hydrotalcite and sodium sulfite, which shows that the preparation of magnesium aluminum water by this preparation method Talc basically does not produce chemical waste liquid that requires additional treatment, which greatly reduces the troublesomeness of reaction product treatment and plays a good role in environmental protection.
  • reaction slurry obtained by formula (4) actually needs to be filtered and washed, and a large amount of washing liquid generated during the washing process is mainly an aqueous solution, so it can be sent back to step 1 for the preparation of sub Magnesium hydrogen sulfate solution, thereby realizing the repeated utilization of resources, reducing the production cost of enterprises, and realizing a green and sustainable circular production preparation system.
  • a commercially available nano-scale magnesium aluminum hydrotalcite has an average particle size of 50nm and a purity of >96%.
  • magnesium aluminum hydrotalcite is a layered double metal hydroxide, it has the advantages of both magnesium hydroxide and aluminum hydroxide flame retardants, and overcomes their respective shortcomings. It has three properties: flame retardancy, smoke elimination, and filling. Function, is a promising high-efficiency, halogen-free, non-toxic, low-smoke new environmentally friendly flame retardant.
  • the magnesium aluminum hydrotalcite flame retardant is decomposed by heat, the heat absorption will reduce the surface temperature of the polymer, and the released inert carbon dioxide gas and water vapor can dilute the concentration of combustible gas, weaken the fire, and play a role in gas phase flame retardancy.
  • the magnesium aluminum hydrotalcite prepared in the present invention also has an excellent flame retardant effect, it is verified by the following tests.
  • this foam material mainly comprises EVA, whipping agent, coupling agent, crosslinking agent, Flame retardant (magnesium aluminum hydrotalcite) and release agent.
  • the EVA foam material prepared by Examples 1-4 and Comparative Example 1-2 is tested for mechanical properties and flame retardancy, wherein the test method includes: measuring hardness according to the national standard GB/T3903.4-2008; /T528-2009 for tensile strength determination; according to the national standard GB/T2406-93, test the limiting oxygen index (LOI) on the HC-2 oxygen index instrument; according to the national standard GB2408-80, test it on the CZF-3 type horizontal vertical combustion The vertical combustion test is tested on the instrument; the cone calorimeter test is carried out according to the 1SO5600 standard test method to measure the maximum heat release rate (PHRR). The test results are shown in Table 1.
  • each group of EVA foam materials has certain mechanical properties and flame retardant properties.
  • Comparative Example 1 and Example 1 under the same amount, commercially available micron-sized magnesium aluminum
  • nanoscale magnesium aluminum hydrotalcite as flame retardant as flame retardant
  • the tensile strength and flame retardant effect of EVA foam material are all reduced, this is because the nanoscale magnesium aluminum prepared in Example 1 Hydrotalcite has better dispersibility and compatibility, and as a flame retardant, the foamed material can maintain relatively good mechanical properties and flame retardant properties.

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  • Organic Chemistry (AREA)
  • Engineering & Computer Science (AREA)
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  • Inorganic Chemistry (AREA)
  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Abstract

一种低成本的镁铝水滑石制备方法，涉及镁铝水滑石制备技术领域，其步骤包括以苦土矿为原料，加入到反应釜中与适量水混合后，通入二氧化硫气体，形成可溶性的亚硫酸氢镁溶液；同时通过在氢氧化钠溶液中加入氢氧化铝加热溶解，并加入碳酸钠，以配置出偏铝酸钠及碳酸钠溶液；然后可将偏铝酸钠及碳酸钠溶液加入到制得的亚硫酸氢镁溶液中，升温加热并搅拌，得到的反应浆料为镁铝水滑石沉淀与亚硫酸钠溶液；再将得到的反应浆料进行过滤和洗涤，可得到镁铝水滑石滤饼、亚硫酸钠滤液以及洗涤液；最后将镁铝水滑石滤饼进行干燥即可得到镁铝水滑石产品；同时可将亚硫酸钠滤液浓缩，以联产亚硫酸钠产品。

Description

一种低成本的镁铝水滑石制备方法 技术领域
本发明涉及镁铝水滑石制备技术领域，尤其指一种低成本的镁铝水滑石制备方法。
 背景技术
镁铝水滑石即Mg/Al-LDHs是一种功能性材料，作为阻燃剂可应用于阻燃材料的制备领域，作为吸酸剂可应用于塑料热稳定剂行业。当镁铝摩尔比为2时，镁铝水滑石的分子式可表示为4Mg2Al(OH)12CO3·4H2O。
 技术问题
在镁铝水滑石最初的制备原料通常包括氯化镁或硫酸镁、氯化铝、氢氧化钠、碳酸钠，其工艺原理如下：
4MgCl 2+2AlCl 3+Na 2CO 3+12NaOH+2H2O=4Mg2Al(OH) 12CO 3·4H 2O+14NaCl                                         式（1）
通过式（1）可以看出，上述制备过程需要消耗大量的氢氧化钠溶液，导致生产成本过高，同时还会形成大量的盐水溶液，即氯化钠废水，在实际生产中的氯化钠废水很难进行回收处理，因此很难实现工业化生产。
为了降低生产成本，减少废液的排放量，现有的一些厂家直接采用高纯度的氢氧化铝以及高纯度的氢氧化镁或氧化镁与碳酸钠为原料，制备镁铝水滑石产品，其工艺原理如下：
4Mg(OH) 2+2Al(OH) 3+Na 2CO 3+2H2O=4Mg2Al(OH) 12CO 3·4H 2O+2NaOH                                            式（2）
通过式（2）可以看出，该生产工艺过程中有低浓度的氢氧化钠溶液产生，其形成的废水依旧需要处理，不仅如此，高纯度的氧化镁或高纯度的氢氧化镁其实是专门生产氧化镁或氢氧化镁厂家的公司通过采用可溶性镁盐为原料加碱制备得到的，其本身的制备成本较高，销售价格也很高。因此采用高纯度的氧化镁或氢氧化镁来制备镁铝水滑石依旧存在前期制备成本偏高的问题。
亚硫酸钠是一种基础化工原料，对于生产硫酸的厂家而言，通常会采用碳酸钠或氢氧化钠吸收净化的二氧化硫气体，从而形成亚硫酸钠产品，亚硫酸钠生产成本的高低则主要在于碳酸钠或氢氧化钠原料的成本，而镁铝水滑石的制备过程恰好需要的碳酸钠与氢氧化钠，因此若利用碳酸钠与氢氧化钠为原料，实现镁铝水滑石与亚硫酸钠的联产，则可有效解决生产成本偏高以及需要处理废水的问题。
 技术解决方案
在本发明的目的在于提供一种低成本的镁铝水滑石制备方法，可通过与亚硫酸钠产品联产的形式变相降低生产成本，并减少废水的产生。
为了解决上述技术问题，本发明采用如下技术方案：一种低成本的镁铝水滑石制备方法，其包括以下步骤：
步骤一、以苦土矿为原料，加入到反应釜中与适量水混合后，通入二氧化硫气体，形成可溶性的亚硫酸氢镁溶液，并过滤掉不溶性的杂质。其中，苦土矿中的主要成分为氧化镁，其余杂质则包括氧化铝、三氧化二铁、二氧化硅，反应釜中通入的二氧化硫气体并不会与杂质中的成分发生反应，而是仅会与氧化镁反应来生成亚硫酸氢镁，因此，该步骤中主要的反应原理如下：
MgO+2SO 2+H 2O=Mg(HSO 3) 2           式（3）
为配置亚硫酸氢镁溶液，以苦土矿为原料在反应釜中与适量水混合后得到的氧化镁浆料浓度控制在2-6%的范围内。
步骤二、在氢氧化钠溶液中加入氢氧化铝加热溶解，并加入碳酸钠，配置出偏铝酸钠及碳酸钠溶液。
步骤三、将步骤二配置的偏铝酸钠及碳酸钠溶液加入到步骤一制得的亚硫酸氢镁溶液中，升温加热并搅拌，得到的反应浆料为镁铝水滑石沉淀与亚硫酸钠溶液，该步骤中的反应原理如下：
4Mg(HSO 3) 2+2NaAl(OH) 4+12NaOH+Na 2CO 3=4Mg2Al(OH) 12CO 3·4H 2O↓+8Na 2SO 3+2H 2O；                           式（4）
步骤四、将步骤三得到的反应浆料进行过滤和洗涤，得到镁铝水滑石滤饼、亚硫酸钠滤液以及洗涤液。
步骤五、将镁铝水滑石滤饼进行干燥，从而可得到镁铝水滑石产品；将亚硫酸钠滤液浓缩，从而可得到亚硫酸钠产品。
步骤六、将步骤四得到的洗涤液送入到步骤一的反应釜中以重复制备亚硫酸氢镁溶液。
优选地，所述苦土矿中的氧化镁含量为90%。
优选地，步骤一中反应釜内的反应温度为25-65℃，反应时间为6-12小时。
更优选地，步骤一中制备得到的亚硫酸氢镁溶液的质量浓度为6-16%。
更优选地，步骤二中氢氧化钠溶液的质量浓度为20-32%。
更优选地，步骤三中的反应温度为85-105℃，反应时间为8-16小时。
更优选地，所述氢氧化铝的白度≥90%，有效含量≥99%，粒度大于200目；所述二氧化硫气体中的二氧化硫体积含量＞8%。
本发明的原理是：利用苦土矿原料中的主要成分即氧化镁在反应釜中混合二氧化硫气体制备以出高纯度的亚硫酸氢镁溶液，然后与偏铝酸钠及碳酸钠溶液、并配以氢氧化钠进行反应，可在得到镁铝水滑石产品的同时，联产亚硫酸钠。
 有益效果
在与现有技术相比，本发明的有益效果在于：
1、以苦土矿作为原料，其中所含的主要成分氧化镁可与二氧化硫溶解反应，且其余杂质则不发生反应，因此无需刻意选用高纯度的氢氧化镁或氧化镁原料，使用成本较为廉价。
2、本发明采用二氧化硫气体作为原料之一，这对于制硫的工厂而言具有较大的应用价值，其可以最大限度的利用排放收集的二氧化硫气体来进行生产制备，而且由于制备出镁铝水滑石产品的同时，还可联产亚硫酸钠，因此相较于传统的制备镁铝水滑石的方法而言，本发明提供的方法会更加适合此类化工厂，所产生的实际效益更显著。
3、由于现有的工艺方法需通过消耗较大量的碳酸钠或氢氧化钠原料来得到镁铝水滑石的单一产物，而本发明提供的工艺方法在消耗氢氧化钠原料后不仅可制备镁铝水滑石，还可联产制备亚硫酸钠，使得氢氧化钠原料的应用能够产生超预期的价值，那么从制备镁铝水滑石的角度而言，由于不再需要消耗额外的氢氧化钠原料，因此相当于变相地降低了生产成本。
4、本发明提供的方法最后还可将洗涤镁铝水滑石沉淀与亚硫酸钠溶液得到的洗涤液送回到初始步骤中配料以重复制备亚硫酸氢镁溶液，从而达到资源重复利用且基本无废液形成的工艺效果，这对于工业生产来说意义重大，具有良好的市场前景。
 本发明的实施方式
在为了便于本领域技术人员的理解，下面结合实施例对本发明作进一步的说明，实施方式提及的内容并非对本发明的限定。
实施例1
在30m 3的搅拌反应釜中，加入20m 3的工业用水，加入苦土矿1吨（氧化镁含量为90%），搅拌，然后通入高浓二氧化硫，在45℃下反应10小时后，氧化镁转变为可溶性的亚硫酸氢镁溶液，过滤，除去杂质，得到精制的亚硫酸氢镁溶液。
其中，上述氧化镁与二氧化硫的摩尔比为1.4。
在15 m 3的溶解槽中加入32%浓度的氢氧化钠溶液8.44吨，加入氢氧化铝0.8775吨，加热到95℃溶解后，加入0.6吨碳酸钠，搅拌至溶解，得到偏铝酸钠及碳酸钠溶液。
在50 m 3的反应槽中，加入20 m 3的亚硫酸氢镁溶液，并加入偏铝酸钠及碳酸钠、氢氧化钠溶液，搅拌，升温到95℃，反应10小时，得到镁铝水滑石沉淀与亚硫酸钠溶液的反应浆料，然后将该反应浆料打入压滤机中进行压滤洗涤，得到镁铝水滑石滤饼、亚硫酸钠滤液以及洗涤液，其中镁铝水滑石滤饼为固含量48%的滤饼。
需要说明的是，本领域的技术人员应该知道，固含量即代表镁铝水滑石浆料压滤洗涤之后的剩余部分占总量的质量百分数。
进一步，将上述滤饼干燥粉碎处理，得到镁铝水滑石产品，将亚硫酸钠滤液去MVR浓缩结晶，从而可得到亚硫酸钠产品，并将上述洗涤液送入到反应釜中配料以重复制备亚硫酸氢镁溶液。
取上述适量的镁铝水滑石产品作样品，分别采用X射线衍射（XDR）、等离子体发射广谱（ICP）、透射电镜（TEM）和激光粒度分析等手段表征和分析该样品，测得该样品的粒径尺寸在20-92nm之间，纯度为99.6%，可证明该产品具有较高的结晶度，满足现有工业级制备方法制备得到的镁铝水滑石产品性能指标。
实施例2
本实施例与实施例1的区别仅在于苦土矿与高浓二氧化硫的反应条件为25℃下反应6小时；氧化镁与二氧化硫的摩尔比为1.6；制备偏铝酸钠及碳酸钠溶液过程中加热到85℃；亚硫酸氢镁溶液、铝酸钠及碳酸钠、氢氧化钠溶液混合搅拌反应的条件为升温到85℃并反应8小时。
取上述制备过程得到的适量镁铝水滑石产品作样品，采用如实施例1同样的检测手段表征和分析该样品，测得该样品的粒径尺寸在20-94nm之间，纯度为99.3%，可证明该产品具有较高的结晶度，满足现有工业级制备方法制备得到的镁铝水滑石产品性能指标。
实施例3
本实施例与实施例1的区别仅在于苦土矿与高浓二氧化硫的反应条件为65℃下反应12小时；氧化镁与二氧化硫的摩尔比为1.8；制备偏铝酸钠及碳酸钠溶液过程中加热到105℃；亚硫酸氢镁溶液、铝酸钠及碳酸钠、氢氧化钠溶液混合搅拌反应的条件为升温到105℃并反应16小时。
取上述制备过程得到的适量镁铝水滑石产品作样品，采用如实施例1同样的检测手段表征和分析该样品，测得该样品的粒径尺寸在20-97nm之间，纯度为99.4%，可证明该产品具有较高的结晶度，满足现有工业级制备方法制备得到的镁铝水滑石产品性能指标。
实施例4
本实施例与实施例1的区别仅在于苦土矿与高浓二氧化硫的反应条件为50℃下反应8小时；氧化镁与二氧化硫的摩尔比为1.2；制备偏铝酸钠及碳酸钠溶液过程中加热到100℃；亚硫酸氢镁溶液、铝酸钠及碳酸钠、氢氧化钠溶液混合搅拌反应的条件为升温到100℃并反应13小时。
取上述制备过程得到的适量镁铝水滑石产品作样品，采用如实施例1同样的检测手段表征和分析该样品，测得该样品的粒径尺寸在20-95nm之间，纯度为99.5%，可证明该产品具有较高的结晶度，满足现有工业级制备方法制备得到的镁铝水滑石产品性能指标。
上述各实施例中首先通过二氧化硫气体与苦土矿中的氧化镁在水中发生反应，制备出亚硫酸氢镁溶液，同时另一边可通过在氢氧化钠溶液中加入氢氧化铝加热溶解，并加入碳酸钠，配置出偏铝酸钠及碳酸钠溶液，然后将偏铝酸钠及碳酸钠溶液加入到亚硫酸氢镁溶液中升温加热搅拌即可得到镁铝水滑石沉淀与亚硫酸钠溶液，再经过后续的过滤、洗涤以及相应的干燥或浓缩处理，即可联产出镁铝水滑石产品和亚硫酸钠产品。其中，二氧化硫气体的加入不仅可以配合氧化镁制备亚硫酸氢镁溶液，还可同时达到回收处理制硫工艺生产尾气的目的。而相较于由于现有的工艺方法需通过消耗较大量的碳酸钠或氢氧化钠原料来得到镁铝水滑石的单一产物而言，本发明提供的制备方法在消耗氢氧化钠原料后不仅可制备镁铝水滑石，还可联产制备亚硫酸钠，这使得氢氧化钠原料的应用能够产生超预期的价值，那么从制备镁铝水滑石的角度而言，由于不再需要消耗额外的氢氧化钠原料，因此相当于变相地降低了生产成本。
本领域的技术人员应该知道，通过式（3）的反应原理可以看出，将氧化镁浆料浓度控制在2-6%的范围内，可使制备得到亚硫酸氢镁溶液质量浓度达到6-16%，再通过式（4）可计算得出，该质量浓度范围内的亚硫酸氢镁在反应体系中相对偏铝酸钠及碳酸钠溶液、氢氧化钠溶液而言会占比较低，那么相应的，适当使用相对更多质量浓度的反应物（偏铝酸钠及碳酸钠溶液、氢氧化钠溶液），则可提高亚硫酸氢镁原料的转化率，从而充分地利用亚硫酸氢镁原料，降低生产成本。
另外，值得一提的是，从式（4）的反应原理来看，最后得到的产物除了镁铝水滑石和亚硫酸钠之外，仅包括一定量的水溶液，这说明通过该制备方法制备镁铝水滑石，基本没有需要额外进行处理的化工废液产生，在极大程度上减轻了反应产物处理的麻烦程度，并起到了良好的环保作用。进一步而言，式（4）得到的反应浆料实际上还需进行过滤和洗涤，在洗涤过程中所产生的大量洗涤液由于主要是水溶液，因此又能重新送入到步骤一用于制备亚硫酸氢镁溶液，从而实现了资源的重复利用，降低了企业的生产成本，实现了绿色、可持续的循环生产制备体系。
对比例1
某市售非纳米级镁铝水滑石，粒径0.6-1μm，纯度＞96%。
对比例2
某市售纳米级镁铝水滑石，平均粒径为50nm，纯度＞96%。
试验检测
由于镁铝水滑石是一种层状双金属氢氧化物，其兼具氢氧化镁和氢氧化铝阻燃剂的优点，又克服了它们各自的不足，具有阻燃、消烟、填充三项功能，是一种很有希望的高效、无卤、无毒、低烟的新型环保阻燃剂。镁铝水滑石阻燃剂受热分解时，由于吸热会降低聚合物表面温度，释放出的惰性二氧化碳气体和水蒸汽能稀释可燃气体浓度，减弱火势，起到气相阻燃作用。为了验证本发明制备的镁铝水滑石同样具备优异的阻燃效果，在此通过下面的试验来对其进行验证。
将各实施例与对比例中的镁铝水滑石作为阻燃剂，以相同分量分别制备相应的EVA发泡材料，该发泡材料主要包括EVA、发泡剂、偶联剂、交联剂、阻燃剂（镁铝水滑石）以及脱模剂。将实施例1-4以及对比例1-2制备得到的EVA发泡材料进行力学性能和阻燃性能检测，其中，测试方法包括：按国标 GB/T3903.4-2008 进行硬度测定；按国标 GB/T528-2009 进行拉伸强度测定；按国标 GB/T2406-93 标准在 HC-2 型氧指数仪上测试极限氧指数 (LOI)；按国标 GB2408-80 标准在 CZF-3 型水平垂直燃烧测定仪上测试垂直燃烧试验；按照 1SO5600 标准试验方法进行锥型量热计试验测量最大热释放速率 (PHRR)。测试结果如表1所示。
Figure dest_path_image002
                        表  1
从表1可以看出，各组EVA发泡材料都具备了一定的力学性能和阻燃性能，将对比例1和实施例1相比，在用量相同的情况下，使用市售微米级镁铝水滑石作为阻燃剂与纳米级镁铝水滑石作为阻燃剂相比，EVA发泡材料的拉升强度和阻燃效果都有所下降，这是因为实施例1所制备的纳米级镁铝水滑石分散性和相容性更好，作为阻燃剂使发泡材料能够保持相对较好的力学性能和阻燃性能。
另外，通过将对比例2和实施例1相比，在用量相同的情况下，二者在力学性能和阻燃性能上的差异都不大，这说明本发明所制备的镁铝水滑石作为阻燃剂与市面上同等产品相比较，同样能够起到优异的阻燃效果。但作为本发明制备方法得到的镁铝水滑石产品，其相较于市面上同等产品而言，制备成本却更低，因此能够拥有更好的市场前景和应用价值。
上述实施例为本发明较佳的实现方案，除此之外，本发明还可以其它方式实现，在不脱离本技术方案构思的前提下任何显而易见的替换均在本发明的保护范围之内。

Claims (7)

  1. 一种低成本的镁铝水滑石制备方法，其特征在于，包括以下步骤：
    步骤一、以苦土矿为原料，加入到反应釜中与适量水混合后，通入二氧化硫气体，形成可溶性的亚硫酸氢镁溶液；
    步骤二、在氢氧化钠溶液中加入氢氧化铝加热溶解，并加入碳酸钠，配置出偏铝酸钠及碳酸钠溶液；
    步骤三、将步骤二配置的偏铝酸钠及碳酸钠溶液加入到步骤一制得的亚硫酸氢镁溶液中，升温加热并搅拌，得到的反应浆料为镁铝水滑石沉淀与亚硫酸钠溶液；
    步骤四、将步骤三得到的反应浆料进行过滤和洗涤，得到镁铝水滑石滤饼、亚硫酸钠滤液以及洗涤液；
    步骤五、将镁铝水滑石滤饼进行干燥，从而可得到镁铝水滑石产品；将亚硫酸钠滤液浓缩，从而可得到亚硫酸钠产品；
    步骤六、将步骤四得到的洗涤液送入到步骤一的反应釜中以重复制备亚硫酸氢镁溶液。
  2. 根据权利要求1所述的低成本的镁铝水滑石制备方法，其特征在于：所述苦土矿中的氧化镁含量为90%。
  3. 根据权利要求1所述的低成本的镁铝水滑石制备方法，其特征在于：步骤一中反应釜内的反应温度为25-65℃，反应时间为6-12小时。
  4. 根据权利要求3所述的低成本的镁铝水滑石制备方法，其特征在于：步骤一中制备得到的亚硫酸氢镁溶液的质量浓度为6-16%。
  5. 根据权利要求1所述的低成本的镁铝水滑石制备方法，其特征在于：步骤二中氢氧化钠溶液的质量浓度为20-32%。
  6. 根据权利要求1所述的低成本的镁铝水滑石制备方法，其特征在于：步骤三中的反应温度为85-105℃，反应时间为8-16小时。
  7. 根据权利要求1所述的低成本的镁铝水滑石制备方法，其特征在于：所述氢氧化铝的白度≥90%，有效含量≥99%，粒度大于200目；所述二氧化硫气体中的二氧化硫体积含量＞8%。
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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1600690A (zh) * 2004-10-13 2005-03-30 浙江大学 以拜尔赤泥为原料制备双金属氧化物和水滑石的方法
WO2006043352A1 (ja) * 2004-10-20 2006-04-27 Sakai Chemical Industry Co., Ltd. ハイドロタルサイト及び合成樹脂組成物
CN1922108A (zh) * 2004-03-16 2007-02-28 学校法人早稻田大学 类水滑石物质及其制造方法、以及有害物质的固定化方法
CN101137581A (zh) * 2005-02-01 2008-03-05 Bhp比利通Ssm技术有限公司 氧化镁的生产方法
CN102203013A (zh) * 2008-11-03 2011-09-28 权五玲 水滑石制备方法
CN102633285A (zh) * 2012-04-17 2012-08-15 北京化工大学 一种一维形貌类水滑石材料及其制备方法
CN106745118A (zh) * 2016-12-30 2017-05-31 洛阳中超新材料股份有限公司 一种镁铝水滑石及制备镁铝水滑石的方法
CN109467109A (zh) * 2018-07-17 2019-03-15 兰州大学 一种形貌可控的镁铝纳米水滑石及其制备方法

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4288452B2 (ja) * 2001-04-03 2009-07-01 戸田工業株式会社 Ｍｇ−Ａｌ系ハイドロタルサイト型粒子粉末の製造法及び塩素含有樹脂安定剤並びに塩素含有樹脂組成物
CN101607173B (zh) * 2008-06-17 2012-05-23 陆泳凯 外部再生循环亚硫酸镁法烟气或废气的脱硫工艺
CN101823697B (zh) * 2010-04-21 2012-02-01 苏州科技学院 利用烟气脱硫废渣制备类水滑石的方法
CN102093525B (zh) * 2010-12-30 2013-07-31 苏州科技学院 一种含有类水滑石的大分子型阻燃剂的制备方法
WO2014033760A1 (en) * 2012-09-02 2014-03-06 Council Of Scientific & Industrial Research A novel process for preparation of synthetic hydrotalcite from industrial waste
CN106882827A (zh) * 2015-12-16 2017-06-23 营口渤海科技有限公司 用于协效阻燃树脂的改性氧化镁脱硫废渣及其制备方法
CN110980779A (zh) * 2019-12-17 2020-04-10 江苏联慧资源环境科技有限公司 一种氧化镁脱硫剂的回收方法
CN110844926A (zh) * 2019-12-17 2020-02-28 江苏联慧资源环境科技有限公司 一种高纯度亚硫酸镁的生产方法

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1922108A (zh) * 2004-03-16 2007-02-28 学校法人早稻田大学 类水滑石物质及其制造方法、以及有害物质的固定化方法
CN1600690A (zh) * 2004-10-13 2005-03-30 浙江大学 以拜尔赤泥为原料制备双金属氧化物和水滑石的方法
WO2006043352A1 (ja) * 2004-10-20 2006-04-27 Sakai Chemical Industry Co., Ltd. ハイドロタルサイト及び合成樹脂組成物
CN101137581A (zh) * 2005-02-01 2008-03-05 Bhp比利通Ssm技术有限公司 氧化镁的生产方法
CN102203013A (zh) * 2008-11-03 2011-09-28 权五玲 水滑石制备方法
CN102633285A (zh) * 2012-04-17 2012-08-15 北京化工大学 一种一维形貌类水滑石材料及其制备方法
CN106745118A (zh) * 2016-12-30 2017-05-31 洛阳中超新材料股份有限公司 一种镁铝水滑石及制备镁铝水滑石的方法
CN109467109A (zh) * 2018-07-17 2019-03-15 兰州大学 一种形貌可控的镁铝纳米水滑石及其制备方法

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