WO2023056675A1 - Method for preparing magnesium-aluminum hydrotalcite by means of mother liquor circulation - Google Patents

Method for preparing magnesium-aluminum hydrotalcite by means of mother liquor circulation Download PDF

Info

Publication number
WO2023056675A1
WO2023056675A1 PCT/CN2021/128173 CN2021128173W WO2023056675A1 WO 2023056675 A1 WO2023056675 A1 WO 2023056675A1 CN 2021128173 W CN2021128173 W CN 2021128173W WO 2023056675 A1 WO2023056675 A1 WO 2023056675A1
Authority
WO
WIPO (PCT)
Prior art keywords
magnesium
aluminum
sodium bicarbonate
source
aluminum hydrotalcite
Prior art date
Application number
PCT/CN2021/128173
Other languages
French (fr)
Chinese (zh)
Inventor
刘志启
吴青山
赵鹏程
周自圆
李娜
焦玲丽
Original Assignee
安徽大学绿色产业创新研究院
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 安徽大学绿色产业创新研究院 filed Critical 安徽大学绿色产业创新研究院
Publication of WO2023056675A1 publication Critical patent/WO2023056675A1/en

Links

Images

Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F7/00—Compounds of aluminium
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2002/00—Crystal-structural characteristics
    • C01P2002/70—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data
    • C01P2002/72—Crystal-structural characteristics defined by measured X-ray, neutron or electron diffraction data by d-values or two theta-values, e.g. as X-ray diagram
    • 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

Definitions

  • the invention relates to the field of preparation methods of magnesium aluminum hydrotalcite, in particular to a method for preparing magnesium aluminum hydrotalcite by circulating mother liquor.
  • Magnesium aluminum hydrotalcite is a layered double hydroxide compound. Because of its structural characteristics, it has important applications in medicine, water purification, and polymer heat stabilizers.
  • magnesium aluminum hydrotalcite Mg 6 Al 2 CO 3 (OH) 16 4H 2 O
  • synthetic magnesium aluminum hydrotalcite is used.
  • the main synthesis method of magnesium aluminum hydrotalcite is co-precipitation method.
  • the most notable feature of the co-precipitation method is that the target material structure can be synthesized by controlling the molar ratio of M 2+ and M 3+ , the type of interlayer anions, reaction time, temperature and pH value of the solution, and it is widely used.
  • the purpose of the present invention is to provide a method for preparing magnesium-aluminum hydrotalcite by circulating mother liquor, so as to solve the cumbersome operation, high cost of raw materials, generation of by-products and waste liquid, and the prepared finished product in the preparation method of magnesium-aluminum hydrotalcite in the prior art.
  • a method for preparing magnesium aluminum hydrotalcite by mother liquor circulation is characterized in that, comprises the following steps:
  • the ratio of the amount of magnesium source to the aluminum source is 1:1 to 5:1; the ratio of the amount and concentration of sodium bicarbonate to the aluminum source is 1:2 to 3:1; the solid content of the mixed slurry is 5% ⁇ 12%;
  • step S2 stirring and reacting the mixed slurry obtained in step S1 at a constant temperature, and suction filtering after the reaction to obtain a filter cake and a filtrate;
  • step S3 washing and drying the filter cake obtained in step S2 to obtain magnesium aluminum hydrotalcite
  • step S4 passing CO 2 into the filtrate obtained in step S3 to obtain a sodium bicarbonate solution;
  • step S4 sodium bicarbonate is added to the obtained sodium bicarbonate solution, so that the concentration of the sodium bicarbonate solution meets the requirements in step S1.
  • step S4 the amount of sodium bicarbonate added to the sodium bicarbonate solution is 0.01-0.05 mol/L.
  • step S1 the ratio of the amount of the magnesium source to the aluminum source is 2.5:1.
  • the ratio of the amount of sodium bicarbonate to the amount of aluminum source is 1:1.
  • the solid content of the finally obtained mixed slurry was 10%.
  • step S2 the mixed slurry is added into a hydrothermal reaction kettle for a constant temperature stirring reaction, the reaction temperature of the constant temperature stirring reaction is 100-200°C, the hydrothermal reaction time is 1-8h, and the stirring speed is 200-700r /min.
  • the optimum value of reaction temperature is 140°C
  • the optimum value of reaction time is 4h
  • the optimum value of stirring speed is 500r/min.
  • step S3 the filter cake is dried at a temperature of 60-90°C.
  • the optimal value of the temperature is 80°C.
  • step S4 the flow rate of CO 2 is 15-100ml/min, and the time of introduction is 0.5-8h. Among them, the optimal value of the flow rate is 50ml/min, and the optimal value of the time is 4h.
  • the present invention is a brand-new method for preparing magnesium aluminum hydrotalcite from mother liquor circulation, and the reaction expression of the present invention is:
  • reaction (1) sodium bicarbonate participates in the reaction and provides an alkaline environment for the reaction, and magnesium hydroxide and aluminum hydroxide are used as magnesium source and aluminum source respectively.
  • the entire reaction process does not introduce anions other than carbonate or bicarbonate ions, so the slurry after the reaction in (1) can be suction-filtered, the filtrate is collected and CO 2 is introduced, and the by-products after the reaction (1) Na 2 CO 3 is converted into NaHCO 3 according to the reaction (2), so as to realize the recycling of raw materials, no waste water discharge, and meet the relevant requirements of the national environmental protection.
  • the magnesium source and the aluminum source do not need to be treated separately, and can be directly used to participate in the preparation of magnesium aluminum hydrotalcite, and the constant temperature stirring reaction can be carried out, without adding other catalysts, etc., and without taking other measure.
  • the by-product of reaction can be directly prepared into sodium bicarbonate solution, and this sodium bicarbonate solution can be used as mother liquor for next time adopting the method of the present invention to prepare magnesium-aluminum hydrotalcite, so the present invention can form mother liquor circulation when preparing magnesium-aluminum hydrotalcite, The whole process is free of any useless by-products.
  • the advantage of the present invention is:
  • the invention has simple operation steps, low cost, no waste liquid generation, all liquids used can be recycled to participate in the reaction again, no by-products and waste water are generated, the atom utilization rate is high, and the concept of green chemistry and national environmental protection requirements are met.
  • the magnesium aluminum hydrotalcite product prepared by the invention has the characteristics of wide source of raw materials, small particle size distribution, few by-products, high purity, regular shape, no anions that are difficult to remove, and the like.
  • Fig. 1 is a flowchart of an embodiment of the present invention.
  • Fig. 2 is an XRD pattern of cyclically synthesized magnesium aluminum hydrotalcite in Example 1 of the present invention.
  • Embodiment 1 As shown in Figure 1, the process of Embodiment 1 is as follows:
  • Step 1 Use aluminum hydroxide as the aluminum source, the dosage is 19.5g; magnesium hydroxide is used as the magnesium source, the dosage is 36.25g; the dosage of sodium bicarbonate is 21g, add 550ml deionized water, and configure the concentration to be 0.36mol/L sodium bicarbonate solution; then aluminum hydroxide and magnesium hydroxide are added to the sodium bicarbonate solution to form a mixed slurry with a magnesium-aluminum ratio of 2.5:1 and a solid content of 10%.
  • Step 2 Add the mixed slurry obtained in Step 1 into a 2L hydrothermal reaction kettle, raise the temperature to 140° C., and stir for 4 hours at a stirring speed of 500 r/min.
  • Step 3 After the reaction in step 2, the filter cake and filtrate were obtained by suction filtration, wherein the filter cake was washed three times, and then dried at 85° C. for 10 h, and the obtained product was magnesium aluminum hydrotalcite.
  • Step 4 feed CO gas into the filtrate obtained in step 3 at a flow rate of 50ml/min, and the feed time continues for 2.5h to obtain sodium bicarbonate solution.
  • Step 5 in the sodium bicarbonate solution that step 4 obtains, add 0.53g sodium bicarbonate, make the concentration of sodium bicarbonate solution meet the requirement of step 1.
  • the present embodiment 2 is basically the same as the embodiment 1, except that in the present embodiment 2, the flow rate of CO2 gas is 25ml/min, and the feeding time is 3h.
  • Present embodiment 2 process is as follows:
  • Step 1 Use aluminum hydroxide as the aluminum source, the dosage is 19.5g; magnesium hydroxide is used as the magnesium source, the dosage is 36.25g; the dosage of sodium bicarbonate is 21g, add 550ml deionized water, and configure the concentration to be 0.36mol/L sodium bicarbonate solution; then aluminum hydroxide and magnesium hydroxide are added to the sodium bicarbonate solution to form a mixed slurry with a magnesium-aluminum ratio of 2.5:1 and a solid content of 10%.
  • Step 2 Add the mixed slurry obtained in Step 1 into a 2L hydrothermal reaction kettle, raise the temperature to 140° C., and stir for 4 hours at a stirring speed of 500 r/min.
  • Step 3 After the reaction in step 2, the filter cake and filtrate were obtained by suction filtration, wherein the filter cake was washed three times, and then dried at 85° C. for 10 h, and the obtained product was magnesium aluminum hydrotalcite.
  • Step 4 feed CO gas into the filtrate obtained in step 3 at a flow rate of 25ml/min, and the feed time continues for 3h to obtain sodium bicarbonate solution.
  • Step 5 in the sodium bicarbonate solution that step 4 obtains, add 0.53g sodium bicarbonate, make the concentration of sodium bicarbonate solution meet the requirement of step 1.
  • the present embodiment 3 is basically the same as the embodiment 1, except that in the present embodiment 3, the flow rate of CO2 gas is 75ml/min, and the feeding time is 1.5h.
  • Present embodiment 3 process is as follows:
  • Step 1 Use aluminum hydroxide as the aluminum source, the dosage is 19.5g; magnesium hydroxide is used as the magnesium source, the dosage is 36.25g; the dosage of sodium bicarbonate is 21g, add 550ml deionized water, and configure the concentration to be 0.36mol/L sodium bicarbonate solution; then aluminum hydroxide and magnesium hydroxide are added to the sodium bicarbonate solution to form a mixed slurry with a magnesium-aluminum ratio of 2.5:1 and a solid content of 10%.
  • Step 2 Add the mixed slurry obtained in Step 1 into a 2L hydrothermal reaction kettle, raise the temperature to 140° C., and stir for 4 hours at a stirring speed of 500 r/min.
  • Step 3 After the reaction in step 2, the filter cake and filtrate were obtained by suction filtration, wherein the filter cake was washed three times, and then dried at 85° C. for 10 h, and the obtained product was magnesium aluminum hydrotalcite.
  • Step 4 feed CO gas into the filtrate obtained in step 3 at a flow rate of 75ml/min, and the feed time continues for 1.5h to obtain sodium bicarbonate solution.
  • Step 5 in the sodium bicarbonate solution that step 4 obtains, add 0.53g sodium bicarbonate, make the concentration of sodium bicarbonate solution meet the requirement of step 1.

Abstract

A method for preparing magnesium-aluminum hydrotalcite by means of mother liquor circulation. The method comprises the following steps: S1, adding a magnesium source and an aluminum source to a sodium bicarbonate solution to prepare a mixed slurry; S2, subjecting the mixed slurry to a constant-temperature stirring reaction; S3, after the reaction in step S2 is finished, carrying out suction filtration to obtain a filter cake and a filtrate, and obtaining a magnesium-aluminum hydrotalcite from the filter cake; S4, introducing CO2 into the filtrate to obtain a sodium bicarbonate solution; and S5, taking the sodium bicarbonate solution obtained in step S4, and repeating steps S1 to S4. The method has simple operation steps, low cost, and no generation of waste liquid; all the liquids used therein can be recycled and repeatedly involved in the reaction without generating any by-products and wastewater; the atom utilization rate is high; and the concept of green chemistry and national environmental protection requirements are met. The magnesium-aluminum hydrotalcite product prepared by means of the method is characterized by having broad sources of raw materials, small particle size distribution, few by-products, a high purity, regular morphology, no anions which are difficult to remove, etc.

Description

一种母液循环制备镁铝水滑石的方法A kind of method that mother liquor circulates and prepares magnesium aluminum hydrotalcite 技术领域technical field
本发明涉及镁铝水滑石制备方法领域，具体是一种母液循环制备镁铝水滑石的方法。The invention relates to the field of preparation methods of magnesium aluminum hydrotalcite, in particular to a method for preparing magnesium aluminum hydrotalcite by circulating mother liquor.
背景技术Background technique
镁铝水滑石是一种层状双氢氧化合物，因其结构的特点使得其在医药，水资源净化，高分子聚合物的热稳定剂等方面都具有重要应用。Magnesium aluminum hydrotalcite is a layered double hydroxide compound. Because of its structural characteristics, it has important applications in medicine, water purification, and polymer heat stabilizers.
据相关文献报道，天然镁铝水滑石(Mg 6Al 2CO 3(OH) 16·4H 2O)主要存在乌拉尔山脉和挪威，且大多数与尖晶石混合，开采和提纯难度较高，故通常采用人工合成镁铝水滑石。目前镁铝水滑石的主要合成办法是共沉淀法。共沉淀法最显著的特点就是可以通过控制M 2+和M 3+的摩尔比、层间阴离子的类型、反应时间、温度和溶液的pH值来合成目标材料结构，应用非常广泛。但共沉淀法成核和晶化同时进行，产物粒径较大颗粒分布不均匀，加工难度较大；通常在合成过程中需要用镁盐溶液或者铝盐溶液作为反应原料，故不可避免的导致有大量碱性废液产生，且副产物较多，处理废液成本较大，不符合国家环保理念。 According to relevant literature reports, natural magnesium aluminum hydrotalcite (Mg 6 Al 2 CO 3 (OH) 16 4H 2 O) mainly exists in the Ural Mountains and Norway, and most of them are mixed with spinel, so it is difficult to mine and purify. Usually synthetic magnesium aluminum hydrotalcite is used. At present, the main synthesis method of magnesium aluminum hydrotalcite is co-precipitation method. The most notable feature of the co-precipitation method is that the target material structure can be synthesized by controlling the molar ratio of M 2+ and M 3+ , the type of interlayer anions, reaction time, temperature and pH value of the solution, and it is widely used. However, the nucleation and crystallization of the co-precipitation method are carried out at the same time, and the particle size of the product is large and the particle distribution is uneven, so the processing is difficult; usually in the synthesis process, magnesium salt solution or aluminum salt solution is used as the reaction raw material, so it is inevitable to cause A large amount of alkaline waste liquid is produced, and there are many by-products, and the cost of waste liquid treatment is relatively high, which does not conform to the national environmental protection concept.
现有技术中，王晓卡等在《一种镁铝水滑石及制备镁铝水滑石的方法》的专利(申请号201611262309.3)中采用氧化镁、氢氧化铝、CO 2以及催化剂催化制备水滑石，该方法在实验过程中首先需要将镁源等制成溶胶前驱体，并且需要将溶胶前驱体与酸溶液性物质接触反应，因此工艺过程繁琐，还会产生难以处理的废酸，不符合绿色化学理念。 In the prior art, Wang Xiaoka et al. used magnesium oxide, aluminum hydroxide, CO 2 and a catalyst to catalyze the preparation of hydrotalcite in the patent (Application No. 201611262309.3) of "A Magnesium Aluminum Hydrotalcite and Its Preparation Method for Magnesium Aluminum Hydrotalcite" , in the experimental process, this method first needs to make a magnesium source into a sol precursor, and needs to contact the sol precursor with an acid solution substance, so the process is cumbersome, and waste acid that is difficult to handle will be produced, which does not meet the requirements of green chemistry concept.
现有技术中，王力耕等申请的《一种镁铝水滑石的制备方法》专利(申请号201210273420.8)中在制备过程中采用可溶性镁盐和铝盐分别作为镁源和铝源制备镁铝水滑石，该方法实验无用的副产物较多，原子利用率较低。In the prior art, in the patent "A Preparation Method of Magnesium Aluminum Hydrotalcite" (application number 201210273420.8) applied by Wang Ligeng, etc., in the preparation process, soluble magnesium salt and aluminum salt are used as magnesium source and aluminum source respectively to prepare magnesium aluminum hydrotalcite , the experimental useless by-products of this method are more, and the utilization rate of atoms is lower.
现有技术中，吴淑航等申请《镁铝碳酸根型水滑石的制备方法》的专利(申请号201710779683.9)通过催化剂催化镁源、铝源和CO 2反应，该反应需要向反应釜内反复通入二氧化碳维持在0.7MPa，并且在反应过程中需要采用碱性催化剂，所使用的原料较多，操作过于繁琐，且该反应合成出的镁铝水滑石有氢氧化 镁残留，纯度不高。 In the prior art, Wu Shuhang and others applied for the patent (application number 201710779683.9) of "Preparation Method of Magnesium Aluminum Carbonate Hydrotalcite" through catalysts to catalyze the reaction of magnesium source, aluminum source and CO 2 , which needs to be repeatedly introduced into the reactor The carbon dioxide is maintained at 0.7MPa, and a basic catalyst needs to be used in the reaction process. The raw materials used are many, and the operation is too cumbersome, and the magnesium aluminum hydrotalcite synthesized by this reaction has magnesium hydroxide residue, and the purity is not high.
发明内容Contents of the invention
本发明的目的是提供一种母液循环制备镁铝水滑石的方法，以解决现有技术镁铝水滑石制备方法存在的操作繁琐、原料成本高、有副产物和废液产生、制备出的成品纯度不高的问题。The purpose of the present invention is to provide a method for preparing magnesium-aluminum hydrotalcite by circulating mother liquor, so as to solve the cumbersome operation, high cost of raw materials, generation of by-products and waste liquid, and the prepared finished product in the preparation method of magnesium-aluminum hydrotalcite in the prior art. The problem of low purity.
为了达到上述目的，本发明所采用的技术方案为：In order to achieve the above object, the technical scheme adopted in the present invention is:
一种母液循环制备镁铝水滑石的方法，其特征在于，包括以下步骤：A method for preparing magnesium aluminum hydrotalcite by mother liquor circulation, is characterized in that, comprises the following steps:
S1、取用镁源和铝源，将镁源和铝源加入至碳酸氢钠溶液中配成混合浆料，其中：S1. Take the magnesium source and the aluminum source, add the magnesium source and the aluminum source to the sodium bicarbonate solution to form a mixed slurry, wherein:
镁源和铝源的物质的量之比为1∶1～5∶1；碳酸氢钠与铝源的物质的量浓度之比为1∶2～3∶1；混合浆料固含量为5％～12％；The ratio of the amount of magnesium source to the aluminum source is 1:1 to 5:1; the ratio of the amount and concentration of sodium bicarbonate to the aluminum source is 1:2 to 3:1; the solid content of the mixed slurry is 5% ~12%;
S2、将步骤S1得到的混合浆料恒温搅拌反应，反应结束后抽滤得到滤饼、滤液；S2, stirring and reacting the mixed slurry obtained in step S1 at a constant temperature, and suction filtering after the reaction to obtain a filter cake and a filtrate;
S3、将步骤S2得到的滤饼进行洗涤、干燥，得到镁铝水滑石；S3, washing and drying the filter cake obtained in step S2 to obtain magnesium aluminum hydrotalcite;
S4、向步骤S3得到的滤液通入CO 2，得到碳酸氢钠溶液； S4, passing CO 2 into the filtrate obtained in step S3 to obtain a sodium bicarbonate solution;
S5、取用步骤S4得到的碳酸氢钠溶液，并重复步骤S1-S4。S5. Take the sodium bicarbonate solution obtained in step S4, and repeat steps S1-S4.
进一步的，步骤S4中，向得到的碳酸氢钠溶液中加入碳酸氢钠，使碳酸氢钠溶液的浓度符合步骤S1中的要求。Further, in step S4, sodium bicarbonate is added to the obtained sodium bicarbonate solution, so that the concentration of the sodium bicarbonate solution meets the requirements in step S1.
进一步的，步骤S4中，向碳酸氢钠溶液中加入的碳酸氢钠的添加量为0.01～0.05mol/L。Further, in step S4, the amount of sodium bicarbonate added to the sodium bicarbonate solution is 0.01-0.05 mol/L.
进一步的，步骤S1中，镁源和铝源的物质的量之比为2.5∶1。碳酸氢钠与铝源的物质的量之比为1∶1。最终得到的混合浆料的固含量为10％。Further, in step S1, the ratio of the amount of the magnesium source to the aluminum source is 2.5:1. The ratio of the amount of sodium bicarbonate to the amount of aluminum source is 1:1. The solid content of the finally obtained mixed slurry was 10%.
进一步的，步骤S2中，将混合浆料加入到水热反应釜中进行恒温搅拌反应，恒温搅拌反应的反应温度为100～200℃，水热反应时间为1～8h，搅拌速度为200～700r/min。其中，反应温度的最优值为140℃，反应时间的最优值为4h，搅拌速度的最优值为500r/min。Further, in step S2, the mixed slurry is added into a hydrothermal reaction kettle for a constant temperature stirring reaction, the reaction temperature of the constant temperature stirring reaction is 100-200°C, the hydrothermal reaction time is 1-8h, and the stirring speed is 200-700r /min. Among them, the optimum value of reaction temperature is 140°C, the optimum value of reaction time is 4h, and the optimum value of stirring speed is 500r/min.
进一步的，步骤S3中，在60～90℃温度下对滤饼进行干燥。其中温度的最优值为80℃。Further, in step S3, the filter cake is dried at a temperature of 60-90°C. The optimal value of the temperature is 80°C.
进一步的，步骤S4中，CO 2通入的流速为15～100ml/min，通入的时间为 0.5～8h。其中通入流速的最优值为50ml/min，通入时间的最优值为4h。 Further, in step S4, the flow rate of CO 2 is 15-100ml/min, and the time of introduction is 0.5-8h. Among them, the optimal value of the flow rate is 50ml/min, and the optimal value of the time is 4h.
本发明是一种全新从母液循环制备镁铝水滑石的方法，本发明的反应表达式为：The present invention is a brand-new method for preparing magnesium aluminum hydrotalcite from mother liquor circulation, and the reaction expression of the present invention is:
Mg(OH) 2+Al(OH) 3+NaHCO 3+H 2O→Mg 6Al 2(OH) 16CO 3·4H 2O+Na 2CO 3   (1)， Mg(OH) 2 +Al(OH) 3 +NaHCO 3 +H 2 O→Mg 6 Al 2 (OH) 16 CO 3 4H 2 O+Na 2 CO 3 (1),
Na 2CO 3+CO 2+H 2O→NaHCO 3      (2)， Na 2 CO 3 +CO 2 +H 2 O→NaHCO 3 (2),
反应(1)中碳酸氢钠参与反应并为反应提供碱性环境，氢氧化镁和氢氧化铝分别作为镁源和铝源。整个反应过程未引入除碳酸根或碳酸氢根离子以外的阴离子，故可以将(1)中的反应后的浆料抽滤，收集滤液并通入CO 2，将反应(1)后的副产物Na 2CO 3按照反应(2)转化为NaHCO 3，从而实现原料的循环使用，无废水排出，符合国家环保有关要求。 In the reaction (1), sodium bicarbonate participates in the reaction and provides an alkaline environment for the reaction, and magnesium hydroxide and aluminum hydroxide are used as magnesium source and aluminum source respectively. The entire reaction process does not introduce anions other than carbonate or bicarbonate ions, so the slurry after the reaction in (1) can be suction-filtered, the filtrate is collected and CO 2 is introduced, and the by-products after the reaction (1) Na 2 CO 3 is converted into NaHCO 3 according to the reaction (2), so as to realize the recycling of raw materials, no waste water discharge, and meet the relevant requirements of the national environmental protection.
通过上述过程可以看出，本发明中无须将镁源和铝源另做处理，可直接用于参与制备镁铝水滑石，并且进行恒温搅拌反应即可，无须添加其他催化剂等，也无须采取其他措施。反应的副产物可直接制备成碳酸氢钠溶液，该碳酸氢钠溶液可作为母液用于下次采用本发明方法制备镁铝水滑石，因此本发明在制备镁铝水滑石时可形成母液循环，整个过程没有任何无用的副产物。It can be seen from the above process that in the present invention, the magnesium source and the aluminum source do not need to be treated separately, and can be directly used to participate in the preparation of magnesium aluminum hydrotalcite, and the constant temperature stirring reaction can be carried out, without adding other catalysts, etc., and without taking other measure. The by-product of reaction can be directly prepared into sodium bicarbonate solution, and this sodium bicarbonate solution can be used as mother liquor for next time adopting the method of the present invention to prepare magnesium-aluminum hydrotalcite, so the present invention can form mother liquor circulation when preparing magnesium-aluminum hydrotalcite, The whole process is free of any useless by-products.
与现有技术相比，本发明的优点为：Compared with prior art, the advantage of the present invention is:
本发明操作步骤简单，成本低，无废液产生，所用所有液体均可循环重新参与反应且无副产物和废水产生，原子利用率高，符合绿色化学理念和国家环保要求。本发明所制备的镁铝水滑石产物具有原料来源广，粒径分布小、副产物少、纯度高、形貌规整、不含难除去的阴离子等特点。The invention has simple operation steps, low cost, no waste liquid generation, all liquids used can be recycled to participate in the reaction again, no by-products and waste water are generated, the atom utilization rate is high, and the concept of green chemistry and national environmental protection requirements are met. The magnesium aluminum hydrotalcite product prepared by the invention has the characteristics of wide source of raw materials, small particle size distribution, few by-products, high purity, regular shape, no anions that are difficult to remove, and the like.
附图说明Description of drawings
图1是本发明实施例流程框图。Fig. 1 is a flowchart of an embodiment of the present invention.
图2是本发明实施例1循环合成镁铝水滑石的XRD图。Fig. 2 is an XRD pattern of cyclically synthesized magnesium aluminum hydrotalcite in Example 1 of the present invention.
具体实施方式Detailed ways
下面结合附图和实施例对本发明进一步说明。The present invention will be further described below in conjunction with the accompanying drawings and embodiments.
实施例1Example 1
如图1所示，本实施例1过程如下：As shown in Figure 1, the process of Embodiment 1 is as follows:
步骤1.采用氢氧化铝作为铝源，用量是19.5g；采用氢氧化镁作为镁源，用量是36.25g；碳酸氢钠用量为21g，加入550ml去离子水，配置成浓度为0.36mol/L的碳酸氢钠溶液；然后将氢氧化铝、氢氧化镁加入碳酸氢钠溶液，由此配成镁铝 比为2.5∶1，固含量为10％的混合浆料。Step 1. Use aluminum hydroxide as the aluminum source, the dosage is 19.5g; magnesium hydroxide is used as the magnesium source, the dosage is 36.25g; the dosage of sodium bicarbonate is 21g, add 550ml deionized water, and configure the concentration to be 0.36mol/L sodium bicarbonate solution; then aluminum hydroxide and magnesium hydroxide are added to the sodium bicarbonate solution to form a mixed slurry with a magnesium-aluminum ratio of 2.5:1 and a solid content of 10%.
步骤2.将步骤1得到的混合浆料加入到2L的水热反应釜中，水热升温至140℃，按搅拌转数500r/min搅拌反应4h。Step 2. Add the mixed slurry obtained in Step 1 into a 2L hydrothermal reaction kettle, raise the temperature to 140° C., and stir for 4 hours at a stirring speed of 500 r/min.
步骤3.步骤2反应完毕后抽滤得到滤饼、滤液，其中将滤饼洗涤三次，然后在85℃下干燥10h，得到的产物即为镁铝水滑石。Step 3. After the reaction in step 2, the filter cake and filtrate were obtained by suction filtration, wherein the filter cake was washed three times, and then dried at 85° C. for 10 h, and the obtained product was magnesium aluminum hydrotalcite.
步骤4.向步骤3得到的滤液按流速50ml/min通入CO 2气体，并且通入时间持续2.5h，得到碳酸氢钠溶液。 Step 4. feed CO gas into the filtrate obtained in step 3 at a flow rate of 50ml/min, and the feed time continues for 2.5h to obtain sodium bicarbonate solution.
步骤5.向步骤4得到的碳酸氢钠溶液中加入0.53g碳酸氢钠，使碳酸氢钠溶液的浓度符合步骤1的要求。Step 5. in the sodium bicarbonate solution that step 4 obtains, add 0.53g sodium bicarbonate, make the concentration of sodium bicarbonate solution meet the requirement of step 1.
步骤6.重复步骤1-5。Step 6. Repeat steps 1-5.
实施例2Example 2
本实施例2与实施例1基本相同，不同的是本实施例2中CO 2气体通入流速为25ml/min，通入时间为3h。本实施例2过程如下： The present embodiment 2 is basically the same as the embodiment 1, except that in the present embodiment 2, the flow rate of CO2 gas is 25ml/min, and the feeding time is 3h. Present embodiment 2 process is as follows:
步骤1.采用氢氧化铝作为铝源，用量是19.5g；采用氢氧化镁作为镁源，用量是36.25g；碳酸氢钠用量为21g，加入550ml去离子水，配置成浓度为0.36mol/L的碳酸氢钠溶液；然后将氢氧化铝、氢氧化镁加入碳酸氢钠溶液，由此配成镁铝比为2.5∶1，固含量为10％的混合浆料。Step 1. Use aluminum hydroxide as the aluminum source, the dosage is 19.5g; magnesium hydroxide is used as the magnesium source, the dosage is 36.25g; the dosage of sodium bicarbonate is 21g, add 550ml deionized water, and configure the concentration to be 0.36mol/L sodium bicarbonate solution; then aluminum hydroxide and magnesium hydroxide are added to the sodium bicarbonate solution to form a mixed slurry with a magnesium-aluminum ratio of 2.5:1 and a solid content of 10%.
步骤2.将步骤1得到的混合浆料加入到2L的水热反应釜中，水热升温至140℃，按搅拌转数500r/min搅拌反应4h。Step 2. Add the mixed slurry obtained in Step 1 into a 2L hydrothermal reaction kettle, raise the temperature to 140° C., and stir for 4 hours at a stirring speed of 500 r/min.
步骤3.步骤2反应完毕后抽滤得到滤饼、滤液，其中将滤饼洗涤三次，然后在85℃下干燥10h，得到的产物即为镁铝水滑石。Step 3. After the reaction in step 2, the filter cake and filtrate were obtained by suction filtration, wherein the filter cake was washed three times, and then dried at 85° C. for 10 h, and the obtained product was magnesium aluminum hydrotalcite.
步骤4.向步骤3得到的滤液按流速25ml/min通入CO 2气体，并且通入时间持续3h，得到碳酸氢钠溶液。 Step 4. feed CO gas into the filtrate obtained in step 3 at a flow rate of 25ml/min, and the feed time continues for 3h to obtain sodium bicarbonate solution.
步骤5.向步骤4得到的碳酸氢钠溶液中加入0.53g碳酸氢钠，使碳酸氢钠溶液的浓度符合步骤1的要求。Step 5. in the sodium bicarbonate solution that step 4 obtains, add 0.53g sodium bicarbonate, make the concentration of sodium bicarbonate solution meet the requirement of step 1.
步骤6.重复步骤1-5。Step 6. Repeat steps 1-5.
实施例3Example 3
本实施例3与实施例1基本相同，不同的是本实施例3中CO 2气体通入流 速为75ml/min，通入时间为1.5h。。本实施例3过程如下： The present embodiment 3 is basically the same as the embodiment 1, except that in the present embodiment 3, the flow rate of CO2 gas is 75ml/min, and the feeding time is 1.5h. . Present embodiment 3 process is as follows:
步骤1.采用氢氧化铝作为铝源，用量是19.5g；采用氢氧化镁作为镁源，用量是36.25g；碳酸氢钠用量为21g，加入550ml去离子水，配置成浓度为0.36mol/L的碳酸氢钠溶液；然后将氢氧化铝、氢氧化镁加入碳酸氢钠溶液，由此配成镁铝比为2.5∶1，固含量为10％的混合浆料。Step 1. Use aluminum hydroxide as the aluminum source, the dosage is 19.5g; magnesium hydroxide is used as the magnesium source, the dosage is 36.25g; the dosage of sodium bicarbonate is 21g, add 550ml deionized water, and configure the concentration to be 0.36mol/L sodium bicarbonate solution; then aluminum hydroxide and magnesium hydroxide are added to the sodium bicarbonate solution to form a mixed slurry with a magnesium-aluminum ratio of 2.5:1 and a solid content of 10%.
步骤2.将步骤1得到的混合浆料加入到2L的水热反应釜中，水热升温至140℃，按搅拌转数500r/min搅拌反应4h。Step 2. Add the mixed slurry obtained in Step 1 into a 2L hydrothermal reaction kettle, raise the temperature to 140° C., and stir for 4 hours at a stirring speed of 500 r/min.
步骤3.步骤2反应完毕后抽滤得到滤饼、滤液，其中将滤饼洗涤三次，然后在85℃下干燥10h，得到的产物即为镁铝水滑石。Step 3. After the reaction in step 2, the filter cake and filtrate were obtained by suction filtration, wherein the filter cake was washed three times, and then dried at 85° C. for 10 h, and the obtained product was magnesium aluminum hydrotalcite.
步骤4.向步骤3得到的滤液按流速75ml/min通入CO 2气体，并且通入时间持续1.5h，得到碳酸氢钠溶液。 Step 4. feed CO gas into the filtrate obtained in step 3 at a flow rate of 75ml/min, and the feed time continues for 1.5h to obtain sodium bicarbonate solution.
步骤5.向步骤4得到的碳酸氢钠溶液中加入0.53g碳酸氢钠，使碳酸氢钠溶液的浓度符合步骤1的要求。Step 5. in the sodium bicarbonate solution that step 4 obtains, add 0.53g sodium bicarbonate, make the concentration of sodium bicarbonate solution meet the requirement of step 1.
步骤6.重复步骤1-5。Step 6. Repeat steps 1-5.
对上述实施例1的产物进行XRD测试，从图2中可以看出，上述实施例1所获得的产物的XRD衍射峰与国际衍射数据中心发布的No.14-0196镁铝水滑石标准谱图一致且在11°，22°，34°分别对应(003)、(006)、(009)晶面，基线平稳，特征峰型尖锐且对称分布，说明结晶度高。且无明显杂质峰，说明合成的水滑石纯度高。Carry out XRD test to the product of above-mentioned embodiment 1, as can be seen from Fig. 2, the XRD diffraction peak of the product obtained in above-mentioned embodiment 1 and the No.14-0196 magnesium aluminum hydrotalcite standard spectrogram issued by International Diffraction Data Center Consistent and corresponding to (003), (006), (009) crystal planes at 11°, 22°, and 34° respectively, the baseline is stable, and the characteristic peaks are sharp and symmetrically distributed, indicating high crystallinity. And there is no obvious impurity peak, indicating that the synthesized hydrotalcite has high purity.
本发明所述的实施例仅仅是对本发明的优选实施方式进行的描述，并非对本发明构思和范围进行限定，在不脱离本发明设计思想的前提下，本领域中工程技术人员对本发明的技术方案作出的各种变型和改进，均应落入本发明的保护范围，本发明请求保护的技术内容，已经全部记载在权利要求书中。The embodiments described in the present invention are only a description of the preferred implementation of the present invention, and are not intended to limit the concept and scope of the present invention. Various modifications and improvements made should fall within the protection scope of the present invention, and the technical content claimed in the present invention has been fully recorded in the claims.

Claims (10)

  1. 一种母液循环制备镁铝水滑石的方法，其特征在于，包括以下步骤：A method for preparing magnesium aluminum hydrotalcite by mother liquor circulation, is characterized in that, comprises the following steps:
    S1、取用镁源和铝源，将镁源和铝源加入至碳酸氢钠溶液中配成混合浆料，其中：S1. Take the magnesium source and the aluminum source, add the magnesium source and the aluminum source to the sodium bicarbonate solution to form a mixed slurry, wherein:
    镁源和铝源的物质的量之比为1∶1～5∶1；碳酸氢钠与铝源的物质的量之比为1∶2～3∶1；混合浆料固含量为5％～12％；The ratio of the amount of substances between the magnesium source and the aluminum source is 1:1~5:1; the ratio of the amount of substances between the sodium bicarbonate and the aluminum source is 1:2~3:1; the solid content of the mixed slurry is 5%~ 12%;
    S2、将步骤S1得到的混合浆料恒温搅拌反应，反应结束后抽滤得到滤饼、滤液；S2, stirring and reacting the mixed slurry obtained in step S1 at a constant temperature, and suction filtering after the reaction to obtain a filter cake and a filtrate;
    S3、将步骤S2得到的滤饼进行洗涤、干燥，得到镁铝水滑石；S3, washing and drying the filter cake obtained in step S2 to obtain magnesium aluminum hydrotalcite;
    S4、向步骤S3得到的滤液通入CO 2，得到碳酸氢钠溶液； S4, passing CO 2 into the filtrate obtained in step S3 to obtain a sodium bicarbonate solution;
    S5、取用步骤S4得到的碳酸氢钠溶液，并重复步骤S1-S4。S5. Take the sodium bicarbonate solution obtained in step S4, and repeat steps S1-S4.
  2. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S4中，向得到的碳酸氢钠溶液中加入碳酸氢钠，使碳酸氢钠溶液的浓度符合步骤S1中的要求。The method for preparing magnesium aluminum hydrotalcite according to claim 1, wherein in step S4, sodium bicarbonate is added to the obtained sodium bicarbonate solution so that the concentration of the sodium bicarbonate solution meets step S1 in the requirements.
  3. 根据权利要求2所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S4中，向碳酸氢钠溶液中加入的碳酸氢钠的添加量为0.01～0.05mol/L。The method for preparing magnesium aluminum hydrotalcite by circulating mother liquor according to claim 2, characterized in that, in step S4, the amount of sodium bicarbonate added to the sodium bicarbonate solution is 0.01-0.05 mol/L.
  4. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S1中，镁源为氢氧化镁、氧化镁中的任意一种或两种按任意比例的混合物。A method for preparing magnesium aluminum hydrotalcite by circulating mother liquor according to claim 1, characterized in that, in step S1, the magnesium source is any one of magnesium hydroxide and magnesium oxide or a mixture of the two in any proportion.
  5. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S1中，铝源为氢氧化铝、氧化铝中的任意一种或两种按任意比例的混合物。The method for preparing magnesium-aluminum hydrotalcite by circulating mother liquor according to claim 1, characterized in that, in step S1, the aluminum source is any one of aluminum hydroxide and aluminum oxide or a mixture of the two in any proportion.
  6. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S1中，镁源和铝源的物质的量之比为2.5∶1。The method for preparing magnesium-aluminum hydrotalcite by circulating mother liquor according to claim 1, characterized in that, in step S1, the ratio of the amount of magnesium source to aluminum source is 2.5:1.
  7. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S1中，碳酸氢钠与铝源的物质的量之比为1∶1。The method for preparing magnesium-aluminum hydrotalcite by circulating mother liquor according to claim 1, characterized in that, in step S1, the ratio of the amount of sodium bicarbonate to the aluminum source is 1:1.
  8. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S2中，将混合浆料加入到水热反应釜中进行恒温搅拌反应，恒温搅拌反应的反应温度为100～200℃，水热反应时间为1～8h，搅拌速度为200～ 700r/min。The method for preparing magnesium-aluminum hydrotalcite according to claim 1, wherein in step S2, the mixed slurry is added to a hydrothermal reaction kettle for a constant temperature stirring reaction, and the reaction temperature of the constant temperature stirring reaction is 100-200°C, the hydrothermal reaction time is 1-8h, and the stirring speed is 200-700r/min.
  9. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S3中，在60～90℃温度下进行干燥。The method for preparing magnesium aluminum hydrotalcite by circulating mother liquor according to claim 1, characterized in that, in step S3, drying is carried out at a temperature of 60-90°C.
  10. 根据权利要求1所述的一种母液循环制备镁铝水滑石的方法，其特征在于，步骤S4中，CO 2通入的流速为15～100ml/min，通入的时间为0.5～8h。 A method for preparing magnesium-aluminum hydrotalcite by circulating mother liquor according to claim 1, characterized in that, in step S4, the flow rate of CO 2 is 15-100ml/min, and the time of feeding is 0.5-8h.
PCT/CN2021/128173 2021-10-09 2021-11-02 Method for preparing magnesium-aluminum hydrotalcite by means of mother liquor circulation WO2023056675A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202111175388.5A CN113830806A (en) 2021-10-09 2021-10-09 Method for preparing magnesium-aluminum hydrotalcite through mother liquor circulation
CN202111175388.5 2021-10-09

Publications (1)

Publication Number Publication Date
WO2023056675A1 true WO2023056675A1 (en) 2023-04-13

Family

ID=78968107

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2021/128173 WO2023056675A1 (en) 2021-10-09 2021-11-02 Method for preparing magnesium-aluminum hydrotalcite by means of mother liquor circulation

Country Status (2)

Country Link
CN (1) CN113830806A (en)
WO (1) WO2023056675A1 (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114904457A (en) * 2022-03-28 2022-08-16 自然资源部天津海水淡化与综合利用研究所 Continuous production equipment and process for carbonate type layered magnesium aluminum hydroxide neutralized by mother liquor carbon
CN114988451A (en) * 2022-05-30 2022-09-02 安徽大学绿色产业创新研究院 Preparation method for synthesizing magnesium-aluminum intercalation material by using magnesium carbonate
CN115057460A (en) * 2022-06-06 2022-09-16 安徽大学绿色产业创新研究院 Method for preparing magnesium-aluminum hydrotalcite from natural hydromagnesite

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5250279A (en) * 1991-12-20 1993-10-05 J. M. Huber Corporation Method for the manufacture of hydrotalcite
CN103288108A (en) * 2013-06-19 2013-09-11 肇庆学院 Method for preparing hydrotalcite compound using brucite
CN107416872A (en) * 2017-09-01 2017-12-01 上海华峰新材料研发科技有限公司 The preparation method of magnalium carbonate form hydrotalcite
CN110092387A (en) * 2019-06-20 2019-08-06 肇庆学院 A kind of hydrotalcite-like composite material and preparation method thereof
CN112479238A (en) * 2020-12-08 2021-03-12 重庆华森制药股份有限公司 Method for preparing aluminum magnesium carbonate
CN113461037A (en) * 2021-07-12 2021-10-01 安徽大学绿色产业创新研究院 Preparation method of magnesium-aluminum hydrotalcite

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102795649A (en) * 2012-08-02 2012-11-28 浙江工业大学 Preparation method for magnesium-aluminium hydrotalcite
EP2890641B1 (en) * 2012-09-02 2019-04-24 Council of Scientific & Industrial Research A novel process for preparation of synthetic hydrotalcite from industrial waste
CN106745118B (en) * 2016-12-30 2018-01-05 洛阳中超新材料股份有限公司 A kind of magnalium hydrotalcite and the method for preparing magnalium hydrotalcite
CN112811449A (en) * 2020-12-30 2021-05-18 江苏艾特克阻燃材料有限公司 Novel method for preparing magnesium-aluminum hydrotalcite

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5250279A (en) * 1991-12-20 1993-10-05 J. M. Huber Corporation Method for the manufacture of hydrotalcite
CN103288108A (en) * 2013-06-19 2013-09-11 肇庆学院 Method for preparing hydrotalcite compound using brucite
CN107416872A (en) * 2017-09-01 2017-12-01 上海华峰新材料研发科技有限公司 The preparation method of magnalium carbonate form hydrotalcite
CN110092387A (en) * 2019-06-20 2019-08-06 肇庆学院 A kind of hydrotalcite-like composite material and preparation method thereof
CN112479238A (en) * 2020-12-08 2021-03-12 重庆华森制药股份有限公司 Method for preparing aluminum magnesium carbonate
CN113461037A (en) * 2021-07-12 2021-10-01 安徽大学绿色产业创新研究院 Preparation method of magnesium-aluminum hydrotalcite

Also Published As

Publication number Publication date
CN113830806A (en) 2021-12-24

Similar Documents

Publication Publication Date Title
WO2023056675A1 (en) Method for preparing magnesium-aluminum hydrotalcite by means of mother liquor circulation
CN102267713B (en) Method for producing high-quality light calcium carbonate by ammonium salt circulation process
CN103130250B (en) Method for preparing active magnesium oxide
CN101259968A (en) Method for preparing trihydrated magnesium carbonate from magnesium chloride-containing bittern by using ammonium carbonate
CN102190320A (en) Method for preparing trihydrated magnesium carbonate by using continuous crystallization process
CN102092749A (en) Preparation method of boehmite
CN107416872B (en) Preparation method of magnesium-aluminum carbonate hydrotalcite
CN1830787A (en) Method of preparing high purity magnesium oxide by closed pyrolysis magnesium chloride hydrate
CN106045523A (en) Method for producing aluminum nitride ceramic powder on basis of Bayer process
CN104591234A (en) Process for preparing light magnesium carbonate from industrial magnesium hydroxide
CN114988451A (en) Preparation method for synthesizing magnesium-aluminum intercalation material by using magnesium carbonate
CN113461037A (en) Preparation method of magnesium-aluminum hydrotalcite
CN114180604A (en) Comprehensive utilization method of waste residues in spice production and synthetic ammonia purge gas
CN109665549A (en) A kind of technique preparing calcium aluminum hydrotalcite using carbon dioxide
CN103044239A (en) Production method of sodium citrate
CN101993097B (en) Method for producing magnesium oxide with co-production of ammonium chloride by taking magnesium carbonate hydrate as intermediate
CN102424409B (en) Method for preparing light magnesium carbonate
CN110078103A (en) A kind of calcium aluminium houghite and preparation method thereof
KR20150104479A (en) Carbon Dioxide Sorbent and Method for Preparing the Same
JP2007126333A (en) Vaterite type disk-shaped calcium carbonate and its production method
CN1174921C (en) High-purity mangesium oxide or magnesium carbonate preparing process in circular medium
WO2019144475A1 (en) Method for preparing high-valence iron salt
WO2017041738A1 (en) Recycling process of wastewater containing ammonium ion and preparation method of metal oxide
RU2283280C1 (en) Method of preparing synthetic a-type zeolite
JP7041784B1 (en) How to make taurine

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 21959764

Country of ref document: EP

Kind code of ref document: A1