Nano-Magnesium Hydroxide Water Purification **![](0logo.gif) [rexresearch.com](../index.htm)** --- **Nano-Magnesium Hydroxide Water Purification** --- [**http://www.azonano.com/news.aspx?newsID=28653**](http://www.azonano.com/news.aspx?newsID=28653) October 31, 2013 **Recycling Rare Earth Elements from Waste Water Using Nano-Magnesium Hydroxide Particles** Many of today's technologies, from hybrid car batteries to flat-screen televisions, rely on materials known as rare earth elements (REEs) that are in short supply, but scientists are reporting development of a new method to recycle them from wastewater. The process, which is described in a study in the journal ACS Applied Materials & Interfaces, could help alleviate economic and environmental pressures facing the REE industry. Zhang Lin and colleagues point out that REEs, such as terbium a a silvery metal so soft it can be cut with a knife a behave in unique ways as super magnets, catalysts or superconductors. That makes them irreplaceable in many of today's tech gadgets and machines. Market watchers expect global demand to rise to at least 185,000 tons by 2015. Although some of these elements are actually plentiful, others are indeed in short supply. According to reports, terbium and dysprosium supplies may only last another 30 years. Attempts so far to recycle them from industrial wastewater are expensive or otherwise impractical. A major challenge is that the elements are typically very diluted in these waters. The team knew that a nanomaterial known as nano-magnesium hydroxide, or nano-Mg(OH)2, was effective at removing some metals and dyes from wastewater. So they set out to understand how the compound worked and whether it would efficiently remove diluted REEs, as well. To test their idea, they produced inexpensive nano-Mg(OH)2 particles, whose shapes resemble flowers when viewed with a high-power microscope. They showed that the material captured more than 85 percent of the REEs that were diluted in wastewater in an initial experiment mimicking real-world conditions. "Recycling REEs from wastewater not only saves rare earth resources and protects the environment, but also brings considerable economic benefits," the researchers state. "The pilot-scale experiment indicated that the self-supported flower-like nano-Mg(OH)2 had great potential to recycle REEs from industrial wastewater." --- [**http://www.acs.org/content/acs/en/pressroom/presspacs/2013/acs-presspac-october-30-2013/Recycling-valuable-materials-used-in-TVs-car-batteries-cell-phones.html**](http://www.acs.org/content/acs/en/pressroom/presspacs/2013/acs-presspac-october-30-2013/Recycling-valuable-materials-used-in-TVs-car-batteries-cell-phones.html) **"Recycling Rare Earth Elements from Industrial Wastewater with Flowerlike Nano-Mg(OH)2"** **ACS Applied Materials & Interfaces** **Recycling valuable materials used in TVs, car batteries, cell phones** Many of todayas technologies, from hybrid car batteries to flat-screen televisions, rely on materials known as rare earth elements (REEs) that are in short supply, but scientists are reporting development of a new method to recycle them from wastewater. The process, which is described in a study in the journal ACS Applied Materials & Interfaces, could help alleviate economic and environmental pressures facing the REE industry. Zhang Lin and colleagues point out that REEs, such as terbium a a silvery metal so soft it can be cut with a knife a behave in unique ways as super magnets, catalysts or superconductors. That makes them irreplaceable in many of todayas tech gadgets and machines. Market watchers expect global demand to rise to at least 185,000 tons by 2015. Although some of these elements are actually plentiful, others are indeed in short supply. According to reports, terbium and dysprosium supplies may only last another 30 years. Attempts so far to recycle them from industrial wastewater are expensive or otherwise impractical. A major challenge is that the elements are typically very diluted in these waters. The team knew that a nanomaterial known as nano-magnesium hydroxide, or nano-Mg(OH)2, was effective at removing some metals and dyes from wastewater. So they set out to understand how the compound worked and whether it would efficiently remove diluted REEs, as well. To test their idea, they produced inexpensive nano-Mg(OH)2 particles, whose shapes resemble flowers when viewed with a high-power microscope. They showed that the material captured more than 85 percent of the REEs that were diluted in wastewater in an initial experiment mimicking real-world conditions. aRecycling REEs from wastewater not only saves rare earth resources and protects the environment, but also brings considerable economic benefits,a the researchers state. aThe pilot-scale experiment indicated that the self-supported flower-like nano-Mg(OH)2 had great potential to recycle REEs from industrial wastewater.a --- [**http://pubs.acs.org/doi/abs/10.1021/am4027967**](http://pubs.acs.org/doi/abs/10.1021/am4027967) **Recycling Rare Earth Elements from Industrial Wastewater with Flowerlike Nano-Mg(OH)2** Chaoran Li a a!, Zanyong Zhuang a a!, Feng Huang AS, Zhicheng Wu a a!, Yangping Hong a a!, and Zhang Lin \*a a! a State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002 P. R. China a! Key Laboratory of design and assembly of functional nanostructures, Chinese Academy of Sciences, Fuzhou, Fujian, 350002 China AS Key Laboratory of Optoelectronic Materials Chemistry and Physical Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, Fujian, 350002 China ACS Appl. Mater. Interfaces, 2013, 5 (19), pp 9719a9725 DOI: 10.1021/am4027967 \*E-mail: zlin@fjirsm.ac.cn. Tel/Fax: (+086)591-83705474. **![](nanomgoh.gif)** Treatment of wastewater containing low-concentration yet highly-expensive rare earth elements (REEs) is one of the vital issues in the REEs separation and refining industry. In this work, the interaction and related mechanism between self-supported flowerlike nano-Mg(OH)2 and low-concentration REEs wastewater were investigated. More than 99% REEs were successfully taken up by nano-Mg(OH)2. Further analysis revealed that the REEs could be collected on the surface of Mg(OH)2 as metal hydroxide nanoparticles (<5 nm). An ion-exchange model was proposed as a critical factor for both guaranteeing the reaction speed and maintaining the self-supported structure of the materials. In addition, a method was developed to further separate the immobilized REEs and the residual magnesium hydroxide by varying the solution pH. In a pilot-scale experiment, the REEs from practical wastewater were immobilized effectively at a high flow rate. We anticipate this work can provide a good example for the recycling of valuable REEs in practical industrial applications. --- **NANO MAGNESIUM HYDROXIDE PATENTS** **Method for enriching low-concentration heavy metal in water by recyclable magnesium hydroxide adsorbent CN102190345 Inventor: ZHANG LIN // WEIZHEN LIU**The invention provides a method for enriching low-concentration heavy metal in water by recyclable magnesium hydroxide adsorbent, which is characterized in that cheap, safe, nontoxic and environment-friendly water treatment agent-magnesium hydroxide serves as adsorbent to treat low-concentration heavy metal in water; then, the magnesium hydroxide reacts with carbon dioxide to desorb and enrich heavy metal; and then, calcination is carried out to recycle the magnesium hydroxide. The method has the advantages of low cost and high treatment capacity, is simple to operate and is environment-friendly; no chemical impurities are introduced into the system; the low-concentration heavy metal can be enriched by tens of times; and the invention can form a continuous technology, and has good environmental benefit and economic benefit **Preparation method of whisker-shaped magnesium hydroxide CN102877115** **Inventor: ZHANG LIN // WEIZHEN LIU**The invention relates to a preparation method of whisker-shaped magnesium hydroxide. The preparation method includes taking magnesium salt crystal whiskers, adding a crystal transforming agent and basic hydroxide, performing crystal form transformation at a certain temperature, subjecting crystallized materials to filtering, washing and drying to obtain the whisker-shaped magnesium hydroxide, wherein the filtrate after the filtration can be recycled through distillation. The magnesium hydroxide prepared through the method is in the whicker shape and provided with good reinforcement effect, and the defect of the deteriorative mechanical property caused by addition of common magnesium hydroxide into polymer based composites is overcome. **Method for preparing flame retardant magnesium hydroxide** **CN102659146****Inventor: ZHICHENG WU // ZHANG LIN**The invention relates to a method for preparing flame retardant magnesium hydroxide. The method is characterized by using undercalcined magnesia powders as raw materials, adding the undercalcined magnesia powders into water containing a composite dispersing agent, stirring and hydrating at a certain temperature for a certain time, and performing a hydrothermal crystallization in a pressure reaction kettle for a certain time. Flame retardant magnesium hydroxide powders with a high dispersibility can be obtained by filtering and drying materials which are subjected to the hydrothermal crystallization, and a filter liquor can be added with a proper amount of water and the dispersing agent to be recycled as water and the dispersing agent in the hydrating. By means of the method, the prepared flame retardant magnesium hydroxide is flaky with the high dispersibility, and the defects of a poor dispersibility, a large specific surface area, easy conglomeration and the like of common magnesium hydroxide in materials such as plastics or rubbers and the like are overcome. According to the method, the sources of required raw materials are rich, the used device and process are simple, and the production cost is low. The prepared flame retardant magnesium hydroxide with the high dispersibility can be widely applied to various industrial production processes. **Nano-Sized Particle-Coated Proppants for Formation Fines Fixation in Proppant Packs****US2013157906**A fracturing fluid, gravel pack fluid and/or frac pack fluid containing particles such as proppants, gravel and/.or sand, may contain an effective amount of a nano-sized particulate additive to fixate or reduce fines migration, where the particulate additive is an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides piezoelectric crystals and pyroelectric crystals. The nano-sized particulate additive is optionally bound to the particles with a coating agent such as an oil, alcohol, glycol, glycol ethers, ketones, terpenes, etc. The particle size of the magnesium oxide or other agent may be nanometer scale but may be a larger scale than nanometer but still relatively small, which scale may provide unique particle charges that help fixate the formation fines. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based. **Novel technology for simultaneously preparing rodlike and sheetlike nano-sized magnesium hydroxide CN103193254**The present invention provides a novel technology combining a precursor precipitation conversion method and an ion exchange technology for simultaneously preparing rodlike and sheetlike nano-sized magnesium hydroxide. Rodlike basic magnesium chloride [Mg2(OH)3Cl.4H2O] is used as a precursor. A mixed solution of sodium hydroxide, alcohol and water flows an ion exchange column filled with rodlike basic magnesium chloride from top to bottom. A solid product in the ion exchange column is washed and dried to get magnesium hydroxide nanorods with a wideth of 100-500 nm and a length of 15-30 [mu]m. The yield is 40%-45%. The eluant is concentrated and separated by crystallization. Magnesium hydroxide nanosheets with a thickness of 20-50 nm and a diameter of 100-300 nm are then prepared through the processes of filtering, washing and drying. The yield is 42%-46%. The present invention has the advantages that: the preparation operations are performed at ambient temperature, the process is simple, and rodlike and sheetlike magnesium hydroxide are prepared simultaneously **SYNTHESIS OF NANO SIZED MAGNESIUM HYDROXIDE KR20130039836**PURPOSE: A manufacturing method of nanosized magnesium hydroxide is provided to synthesize magnesium hydroxide with excellent dispersity and crystallinity in short time by using microwaves. CONSTITUTION: A manufacturing method of nanosized magnesium comprises a step of mixing a magnesium salt and alkali source; a step of treating microwaves of the mixture solution; a step of cooling washing the result; and a step of drying the result. Waves with an ultra high frequency of 40-1400W is irradiated to the mixture solution for 5-30 minutes. The mixture solution is one or more of MgSO4, MgCl2, and MgNO3. The magnesium salt is used with a concentration of 0.5-3.0 mol/L. The alkali source is one selected from NaOH, ammonia solution, and amine-based compound. **Preparation method of magnesium oxide nano particle with yolk-shaped core-shell structure CN103011208**The invention relates to a preparation method of a magnesium oxide nano particle with a yolk-shaped core-shell structure. The preparation method is characterized in that the preparation method comprises the following steps of (1) weighing 0.01-0.06g magnesium hydroxide, adding 30-60ml sodium dodecyl sulfate solution with a concentration of 10-50g/L, mixing for 20-40min, conducting ultrasonic treatment for 1-5min, and marking as a solution (1), (2) placing the solution (1) into a 100ml hydrothermal reaction kettle, treating for 2-5h at 150-180 DEG C, naturally cooling for 12-24h, conducting water washing and absolute ethyl alcohol washing for three times respectively, centrifuging, drying for 2-5h at 50-80 DEG C, and obtaining a product (2), and (3) calcining the product (2) for 30-120min at 400-600 DEG C, and obtaining the magnesium oxide nano particle with the core-shell structure. The preparation method is simple and easy to control, and the prepared magnesium oxide nano particle with the yolk core-shell structure has the characteristics of large specific surface area, large mesoporous rate, high gas adsorbability, and the like. **Method for preparing surface modification nano-magnesium hydroxide CN102964879**The invention discloses a method for preparing surface modification nano-magnesium hydroxide. Firstly, phosphate ester compound solution with the mass fraction of 5-20% is adopted to carry out surface modification on magnesium hydroxide, and then, terminal amino polyhydric alcohol ester solution with the mass fraction of 10-20% is adopted to carry out secondary modification through a dry modification method. The prepared modified magnesium hydroxide is applied to the high filling modification of macromolecular materials, and the processing fluidity and flame retardant property of the materials can be obviously improved. **Nano-Sized Particles for Formation Fines Fixation US2012267102**A treating fluid may contain an effective amount of a particulate additive to fixate or reduce fines migration, where the particulate additive is an alkaline earth metal oxide alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides piezoelectric crystals and pyroelectric crystals. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that help fixate the formation fines. These treating fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing, completion fluids, gravel packing fluids and fluid loss pills. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based. **Method for preparing magnesium oxide nano powder material CN102502723**The invention provides a method for preparing a magnesium oxide nano powder material, comprising the following specific steps: adding polyvinyl alcohol aqueous solution of concentration 3 wt% into magnesium hydroxide solid at a ratio of 0.5-0.8L/kg, and uniformly mixing; adding oxalic acid dihydrate solid with equal matter of as magnesium hydroxide; grinding for 20-30 min, and drying the mixture at 70-100 DEG C; calcinating the mixture to a temperature in a range of 650-750 DEG C and keeping for 1-2 h. The obtained magnesium oxide particles are spherical, with particle size of 10-20 nm and uniform granularity. **Reaction system and method for preparing nano magnesium hydroxide CN102153114**The invention discloses a reaction system and a method for preparing nano magnesium hydroxide. The invention adopts the technical scheme that the reaction system comprises a feeding device, a reaction device and a storage tank; the feeding device is connected with the reaction device; and the reaction device is connected with the storage tank. The method for preparing the nano magnesium hydroxidecomprises the following steps of: respectively placing soluble magnesium salt solution and alkali liquor in different material tanks; simultaneously starting a constant flow pump of the feeding device, simultaneously feeding the same volume of the soluble magnesium salt solution and the alkali liquor into the reaction device, controlling the flowing speed of reaction solution in the range of 2 to20m/s, simultaneously starting ultrasonic waves of the reaction device, controlling the frequency of the ultrasonic waves in the range of 20 to 100kHz and controlling the power of the ultrasonic waves in the range of 50 to 800W; and carrying out washing, solid-liquid separation and drying on reacted slurry to obtain a target product.; The reaction system and the method are simple to operate and have small investment, short production period and mild production condition. The prepared nano powder have homogeneous appearance, narrow size distribution and good dispersity and is particularly suitable for industrial production. **MANUFACTURING METHOD OF MAGNESIUM OXIDE PARTICLES WITH CONTROLLED SIZE KR101193261**PURPOSE: A manufacturing method of magnesium oxide is provided to manufacture magnesium oxide into various nano and micro particle sizes by controlling dilution concentration when washing the magnesium oxide. CONSTITUTION: A manufacturing method of magnesium oxide comprises the following steps: manufacturing a mixture by mixing a magnesium compound solution with a base solution; agitating the mixture at 10-40 deg. Celsius for 2-30 hours at 50-800 rpm in the water phase to manufacture and precipitate magnesium hydroxide; diluting the precipitated magnesium hydroxide with one of distilled water or hydrophilic organic solvent; washing the diluted magnesium hydroxide in a pressure filtration mode; drying the washed magnesium hydroxide; and manufacturing magnesium hydroxide by sintering the dried magnesium oxide. 1-3 equivalence ratio of the base is used for the magnesium compound. **Method for preparing monodisperse flaky magnesium hydroxide flame retardant CN102205980**The invention relates to a method for preparing a monodisperse flaky magnesium hydroxide flame retardant. The method comprises the following steps of: preparing a soluble magnesium salt into a solution with magnesium ion concentration of more than 0.5mol/l; adding sodium hydroxide with hydroxyl ion concentration of more than 0.5mol/l or an ammonia aqueous solution at a temperature of 25-60 DEG C, a stirring rate of 1,500-4,000rmp and a constant flow rate under a constant pressure for precipitation reaction; reacting until the molar ratio of magnesium ions to hydroxyl ions is 1 to 2; transferring the reacted slurry into a high pressure reaction kettle, wherein the hydro-thermal reaction temperature is 100-200 DEG C, the reaction time is 1-6 hours and the stirring rate is 300-700 rpm; and after filtering and washing a product, drying the product at the temperature of 100-160 DEG C for 4-6 hours to obtain the magnesium hydroxide flame retardant which has a shape of hexagonal sheet or circular sheet, a grain size from 200nm to 500 nm and excellent dispersibility. By using the method provided by the invention, the problems that nano-sized magnesium hydroxide is subjected to hydro-thermal reaction only in a strong alkali system at a higher temperature and the requirement on equipment material is higher are solved. **Preparation method of flaky nano-sized magnesium oxide CN101920977**The invention relates to a preparation method of flaky nano-sized magnesium oxide, belonging to the technical field of materials. The preparation method comprises the following steps of: (1) adding soluble magnesium salt, organic dispersant and precipitant ammonia water into water, and carrying out precipitation reaction under the condition of stirring to obtain precipitate magnesium hydroxide precursor, wherein the reaction temperature is 40-50 DEG C, the stirring speed is 300-400rpm, and the reaction time is at least 60min; and (2) calcining the magnesium hydroxide precursor at 500-600 DEG C to obtain the flaky nano-sized magnesium oxide. The method of the invention has the advantages of easy acquisition of raw materials, simple processes and the like, is suitable for industrialized production, and has good application prospects in the technical field of infrared camouflage materials. **Method for preparing magnesium hydroxide CN101698490**The invention relates to a method for preparing magnesium hydroxide, which comprises the following steps: a step of preparing magnesium hydroxide suspension, a step of separating magnesium hydroxide from the magnesium hydroxide suspension and a step of modifying the obtained magnesium hydroxide by using a modifier, wherein the step of preparing the magnesium hydroxide suspension comprises the following steps: adding a magnesium salt solution and an ammonia water solution to a spiral-channel type revolving bed for reacting to obtain the magnesium hydroxide suspension, wherein the concentration of the magnesium salt solution is 0.5-3mol/L, and the concentration of the ammonia water solution is 1-7mol/L. By using the method of the invention, on one hand, fine-grained nano-level magnesium hydroxide can be obtained, and on the other hand, the spiral-channel type revolving bed can not be blocked, thus the method of the invention can improve the production efficiency and can be applied to large-scale industrial production. **METHOD OF CHEAP NANOPARTICLE MAGNESIA KR20110034887**PURPOSE: A method for cost effectively manufacturing nano-particle magnesia is provided to simplify manufacturing processes by capturing and recycling carbon dioxide generated from the calcinations of dolomite. CONSTITUTION: Dolomite is calcined to obtain lightly burned dolomite. Carbon dioxide generated from the calcinating process of the dolomite is captured. The lightly burned dolomite, water, and magnesium chloride are mixed and undergoes a hydrothermal reaction in order to obtain magnesium hydroxide particles. The magnesium hydroxide particles are dispersed in water. The carbon dioxide is introduced to obtain magnesium carbonate particles. The magnesium carbonate is calcined to obtain magnesia particles. C**omplex magnesium hydroxide nano structure CN101654263**The invention relates to a method for synthesizing a complex magnesium hydroxide nano structure, belonging to the technical field of nano materials for fireproof coatings. The method comprises the following steps: taking magnesium chloride hexahydrate (MgCl2.H2O), glycine (glycine, CH2(NH2)COOH, C2H5NO2) and sodium hydroxide (NaOH) as raw materials and preparing aqueous solution containing the three raw materials as initial reaction solution at room temperature, placing the initial reaction solution in a stainless steel reaction kettle with a polytetrafluoroethylene liner to be heated at 210-240 DEG C for 8-48h, thus obtaining the complex magnesium hydroxide nano structure. Synthesis of the complex magnesium hydroxide nano structure by the method is realized by employing the glycine, a biomolecule, as one of the raw materials to participate in the reaction, which provides a new synthetic method and a new material for researching the properties and practical purposes of the complex magnesium hydroxide nano structure. Synthesis of the complex magnesium hydroxide nano structure has great significance in both academic research and application. **Method of producing large-scale and/or nano-scale, coated, disagglomerated magnesium hydroxide particles EP2141124**Producing coated magnesium hydroxide particles, comprises contacting (a) a magnesium salt solution with (b) an alkali hydroxide solution under the formation of a reaction mixture to precipitate coated magnesium hydroxide particles, where at least one of the additives comprising a growth inhibitor, a dispersing agent-b and/or an aqueous stearate solution is contained in at least one of the solutions (a) and (b), or brought into contact with the reaction mixture obtained by contacting (a) and (b), for producing an aqueous suspension or dispersion of coated magnesium hydroxide particles. Independent claims are included for: (1) coated primary magnesium hydroxide particles obtained by the process; and (2) an organic or aqueous suspension or dispersion comprising coarse- and/or nanoscale, and preferably coated, optionally deagglomerated and optionally functionalized magnesium hydroxide particles obtained by the process. **Method of producing large-scale and/or nano-scale, coated, disagglomerated and preferably functionalised magnesium hydroxide particles EP2141189**Preparation of hardenable mass containing coarse and/or nanoscalic, coated, deagglomerated magnesium hydroxide particle, comprises (a) providing the magnesium hydroxide particle in dried form; (b) dispersing or suspending the particle in an organic solvent; (c1) either bead milling the suspension or dispersion in the presence of a dispersing agent or (c2) treating the suspension or dispersion with ultrasound in the presence of the dispersing agent; and (d1) mixing the obtained dispersion containing the particle with a component of a hardenable mass. Preparation of hardenable mass containing coarse and/or nanoscalic, coated, deagglomerated magnesium hydroxide particle, comprises (a) providing the magnesium hydroxide particle in dried form; (b) dispersing or suspending the particle in an organic solvent; (c1) either bead milling the suspension or dispersion in the presence of a dispersing agent or (c2) treating the suspension or dispersion with ultrasound in the presence of the dispersing agent; and (d1) either mixing the obtained dispersion containing the particle with a component of a hardenable mass or (d2) mixing the dispersion containing the particle with a components of the hardenable mass. Independent claims are included for: (1) the preparation of filled polymer dispersion containing the particle comprising (aa) providing the particle as a suspension or dispersion in an aqueous solvent containing a dispersing agent or in dried form, (bb) optionally dispersing and/or suspending the dried magnesium hydroxide powder in an aqueous solvent, carrying out the steps (c1) or (c2), (dd1) mixing the dispersion obtained from (c1) with an aqueous polymer dispersion or (dd2) mixing the dispersion obtained from (c2) with the aqueous polymer dispersion, and (e1) forming the polymers from the obtained polymer dispersion; (2) the hardenable mass, preferably filled duroplast or thermoplast obtained by the above process; (3) an aqueous filled polymer dispersion containing the magnesium hydroxide particle obtained by the above process; and (4) a composite material containing the hardenable mass and further a reinforcing agent. **Manufacturing procedure for large-scale and/or nano-scale, coated, disagglomerated magnesium hydroxide particles EP2154177**Preparing filled thermoplastic material, comprises: (a) providing a thermoplastic material; (b) providing a rough- and/or nanoscale, coated, magnesium hydroxide particles as suspension or dispersion in an aqueous or organic solvents; (c) feeding the coarse and/or nanoscale, coated magnesium hydroxide particles in suspension or dispersion of the thermoplastic material; (d) mixing the magnesium hydroxide particles with the heated, molten thermoplastic material; and (e) removing the solvent of the suspension or dispersion from the mixture. Preparing filled thermoplastic material containing coarse- and/or nanoscale, coated and deagglomerated magnesium hydroxide particles in the form of coated primary particles, comprises: (a) providing a thermoplastic material; (b) providing a rough- and/or nanoscale, coated, magnesium hydroxide particles as suspension or dispersion in an aqueous or organic solvents; (c) feeding the coarse and/or nanoscale, coated magnesium hydroxide particles in suspension or dispersion to thermoplastic material; (d) mixing the magnesium hydroxide particles with the heated, molten thermoplastic material; and (e) optionally removing the solvent of the suspension or dispersion from the mixture.; Independent claims are included for: (1) an apparatus for producing filled thermoplastic comprising coarse and/or nanoscale, coated magnesium hydroxide particles in the form of coated primary particles, where the magnesium hydroxide particles are added to the thermoplastic material in the form of a suspension or dispersion, comprises a first injection device (2) for thermoplastic polymer, a second injection device (3) for a dispersion/suspension containing coarse and/or nanoscale, coated, deagglomerated magnesium hydroxide particles, a first zone in which the thermoplastic is fed by the injection device, a second zone, in which the dispersion/suspension of the magnesium hydroxide particles is fed by injection device, optionally a first- and second degassing zone (7), a heated region for melting the thermoplastic and a device for mixing molten thermoplastics and magnesium hydroxide particles; and (2) the filled thermoplastic material containing coarse- and/or nanoscale, coated and deagglomerated magnesium hydroxide particles obtained by the process. **Method of preparing loose acicular magnesium hydroxide nano-particle CN101549877**The present invention relate to a method of preparing loose acicular magnesium hydroxide nano-particle. The particular steps are: preparing the magnesian soluble metal salt into 0.1-4 mol/l solution; second step, preparing the settling agent molar conentration with the metallic ion molar conentration of the salt solution in the first step as 1-3:1; third step, the coating agent solution prepared with concentration of 0.01-0.2mol/l; fourth step, in the ventilation condition, adding the obtained solution of the first, second, third step into reactor simultaneity at a temperature of 10-25 DEG; fifth step, using stirrer agitating strongly in the charging barrel, and foamy product can float to water surface in short time, standing and aging at the temperature of 10-25 DEG for 8-14 hours; sixth step, when washing, ejecting the solution beneath the floating particles, and adding de-ionized water or distilled water. To agitate for 15-30 minutes and standing ejecting, the coating particles can float to solution surface in few minutes and the lower layer is transparent water solution, doing like this for 3-5 times and pumping filtration, vacuum drying the filter mass at a temperature of 75-100 DEG for 8-24 hours. The invention is provided with advantages of simple apparatus and technics, easy operation; small apparatus, small occupying, low cost, convenient maintenance; continuous production and the production process is green and environment friendly. **Solid-phase method for preparing nano-sized magnesium hydroxide CN101780968**The invention relates to a solid-phase method for preparing nano-sized magnesium hydroxide. The solid-phase method comprises the following steps of: weighting and putting MgCl2\*6H2O in a drying cabinet, drying at 100 DEG C and taking out; putting a part of drying matter and NaOH in an agate mortar, grinding and taking out; then, grinding the other part of drying matter in the agate mortar, mixing and grinding the ground products of the NaOH and the NaCl; enabling the two ground products to respectively stand for 24h, respectively washing with distilled water to remove NaCl, drying and grinding into powder nano-sized magnesium hydroxide to obtain a sample 3 and a sample 1; and then, respectively adding a certain amount of surface active agents and grinding to obtain a sample 4 and sample 2. The invention overcomes the defects of preparation methods, such as a direct precipitation method, an even precipitation method, a precipitation-azeotropic distillation method, a hydro-thermal method, and the like, prepares nano-sized magnesium hydroxide by utilizing a solid-phase reaction and has the advantages of high product purity, smaller particle diameters, regular shapes, easy and practical reaction, mild conditions, short time, less energy consumption, low cost and little environmental pollution. **Method for preparing magnesium oxide powder by magnesium sulphate demanganization CN101456564**The invention relates to a method for preparing magnesia nano powder through demanganization of a magnesium sulphate waste solution, which comprises: adopting the magnesium sulphate waste solution obtained after acidolysis and nickel extraction of nickel-containing serpentine as a raw material, and adopting an oxidant and ammonia water or a sodium hydroxide solution to adjust the pH value and perform aging, filtration and demanganization; adopting a sodium carbonate solution or sodium bicarbonate and ammonia water or an ammonium carbonate solution as a precipitant and anhydrous alcohol as a stabilizer and dehydrant, and performing ultrasonic chemical precipitation reaction at a temperature of between 30 and 55 DEG C; and preparing the magnesia nano powder after heat insulation, aging, centrifugal separation, washing, microwave drying and calcination. The particle diameter of the prepared magnesia nano powder is between 20 and 50 nanometers; powder particles are spherical, are uniformly distributed and have less agglomeration; and the recovery rate of magnesia reaches more than 95 percent. **Method for preparing magnesium hydrate nano powder by active acid leaching nickel-containing serpentine CN101456565**The invention relates to a method for preparing magnesium hydroxide nano powder through activation and acid leaching of nickel-containing serpentine, which comprises: adopting the nickel-containing serpentine as a raw material and a sulfuric acid as a leaching agent, removing iron by an amarillite method, removing heavy metals by a vulcanization method, adopting a NaOH solution for neutralization and nickel deposit, and adopting an oxidant and an ammonia water solution to adjust the pH value and perform aging, filtration and demanganization; and adopting ammonia water or a sodium hydroxide solution as a precipitant and anhydrous alcohol as a stabilizer and dehydrant, and performing ultrasonic chemical precipitation reaction at a temperature of between 30 and 55 DEG C; ; and preparing the magnesium hydroxide nano powder after heat insulation, aging, centrifugal separation, washing and microwave drying, wherein the particle diameter of the magnesium hydroxide nano powder is between 20 and 50 nanometers, and particles of the magnesium hydroxide nano powder are uniformly distributed. **NANO-SIZED PARTICLE-COATED PROPPANTS FOR FORMATION FINES FIXATION IN PROPPANT PACKS WO2009085377**A fracturing fluid, gravel pack fluid and/or frac pack fluid containing particles such as proppants, gravel and/.or sand, may contain an effective amount of a nano-sized particulate additive to fixate or reduce fines migration, where the particulate additive is an alkaline earth metal oxide, alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides piezoelectric crystals and pyroelectric crystals. The nano-sized particulate additive is bound to the particles with a coating agent such as an oil. The particle size of the magnesium oxide or other agent may be nanometer scale, which scale may provide unique particle charges that help fixate the formation fines. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon- based. **NANO-SIZED PARTICLES FOR FORMATION FINES FIXATION WO2009079092**A treating fluid may contain an effective amount of a particulate additive to fixate or reduce fines migration, where the particulate additive is an alkaline earth metal oxide alkaline earth metal hydroxide, alkali metal oxides, alkali metal hydroxides transition metal oxides, transition metal hydroxides, post-transition metal oxides, post-transition metal hydroxides piezoelectric crystals and pyroelectric crystals. The particle size of the magnesium oxide or other agent may be nano-meter scale, which scale may provide unique particle charges that help fixate the formation fines. These treating fluids may be used as treatment fluids for subterranean hydrocarbon formations, such as in hydraulic fracturing, completion fluids, gravel packing fluids and fluid loss pills. The carrier fluid used in the treating fluid may be aqueous, brine, alcoholic or hydrocarbon-based. **Method for preparing nano-scale magnesium hydrate by extracting magnesium from low grade laterite nickel ore hydrochloric acid leaching liquid CN101376510**The invention discloses a method for preparing nano magnesium hydroxide through extracting magnesium from low-grade lateritic nickel hydrochloric-acid leaching liquid. Ferrum is extracted and separated from the leaching liquid at room temperature; the pH value is adjusted to remove Al and Cr; a curing ingredient is added to separate valuable metals that are Ni, Co, Mn and Cu from the leaching liquid; excess oxalic amine is added to remove calcium; alkali is added to the leaching liquid at the temperature ranging from 30 to 90 DEG C and used as a precipitator; a surface active agent, the concentration of which is 2 to 10 percent, is added; the reaction is conducted for 10 to 120 minutes under a constant temperature, the ageing is conducted for 30 to 240 minutes, and the nano magnesium hydroxide is obtained.; The method extracts the magnesium from the leaching liquid of the low-grade lateritic nickel to prepare the nano magnesium hydroxide under the room temperature and normal atmosphere, overcomes the magnesium resource waste problem in the existing low-grade lateritic nickel hydrochloric-acid leaching technology, saves the resource, and reduces the waste. **Preparation of high length-diameter ratio magnesium hydroxide sulfate hydrate whisker CN101348937**A preparation method for hydrated basic magnesium sulfate crystal whisker with high-aspect ratio belongs to the technical field of inorganic chemical material preparation. The method comprises the following steps: water-soluble magnesium salt and inorganic base are taken as raw materials so as to prepare a precursor for nano magnesium hydroxide with better crystallinity and dispersivity in a substrate double-injection synthesis mode at a temperature between 10 and 90 DEG C; then the precursor is added into aqueous solution containing sulfate and micro chelated morphological control agent so as to carry out hydrothermal reaction at a temperature between 100 and 250 DEG C for 2 to 20 hours; and finally, one-dimensional growth of hydrothermal products is promoted by means of the selective adsorption and slow release action of the morphological control agent so as to prepare the hydrated basic magnesium sulfate crystal whisker with the average length of between 40 and 400mu m, the average diameter of between 0.05 and 0.2 mu m, the aspect ratio of between 200 and 2,000 and the main content more than 98 percent. The preparation method has the advantages of simple process, low cost, high added value of the product and easy industrial popularization; moreover, the product can be used in industries such as plastics, rubber, resin and ceramics as a reinforcing material. **NANOPARTICLE MAGNESIA AND METHOD FOR PREPARING THE SAME KR20100024288**PURPOSE: A nano particle magnesia and a method of manufacturing thereof are provided to facilitate a crystallizing process of a nano particle in a low temperature with an improved sintering characteristic. CONSTITUTION: A method of manufacturing nano particle magnesia comprises the following steps: step 1, producing magnesium hydroxide by adding an alkali compound to magnesium chloride; step 2, forming magnesium oxide by heating magnesium hydroxide at 40~150 deg C; and step 3, forming a nano particle magnesia by heating magnesium oxide at 800~1,600 deg C in an electric furnace under a pressure reduction. A template material and a solvent are added to the first or the third step. **Method for preparing magnesium hydroxide with microemulsion in phase opposition CN101318673**The invention discloses a method for preparing magnesium hydroxide by a reversed phase single micro-emulsion. The method adopts a new preparation process; after selection of the raw chemical substances, a surfactant polyethylene glycol octyl phenyl ether, a cosurfactant n-hexyl alcohol, the oil-phase cyclohexane, and the aqueous-phase magnesium chloride water solution are placed in a flask for stirring and mixing to gain a clear reversed phase single micro-emulsion; ; the micro-emulsion is added with ammonia gas to adjust the pH value until the micro-emulsion is alkaline, and a white emulsion is gained after reaction and becomes a clear precipitate after heating and emulsion breaking, the clear precipitate is filtered under the vacuum state, washed and filtered by deionized water and absolute ethyl alcohol, dried under minus 55 DEG C frozen state and 15Pa vacuum state, ground, sieved by a 625-mesh sieve, and the white, flakelike, crystalline, and nano-sized magnesium hydroxide powder is obtained. The method has the advantages of less equipment requirement, short technological process and no environmental pollution; the product yield is up to 97%, the product purity is up to 98%, the product has high precision, the powder has the average particle size of 80nm and the average thickness of 20nm, good thermal stability, 353 DEG C initial decomposition temperature, reaches the maximum decomposition rate at the temperature of 387 DEG C, and can match a plurality of organic matters to prepare a plurality of fire retardant materials. **Nano magnesium hydrate combustion inhibitor using agustite as crystal nucleon component and preparation method CN101284993**The invention relates to nanometer magnesium hydroxide flame retardant with apatite as crystal nucleus composition, wherein the proportion of apatite composition and magnesium hydroxide composition which are respectively calculated with the molar weight of calcium and magnesium is (1-3):(3-6). A preparation method of the invention comprises the following steps that: under the condition of sufficient stirring, a phosphate aqueous solution and a magnesium salt solution are added to an aqueous solution which has the pH value between 10 and 13 and comprises calcium salt and surfactant composition so as to carry out reaction; the proportion of calcium salt and magnesium salt which are calculated with the molar weight of calcium and magnesium is (1-3):(3-6); the proportion of magnesium salt and phosphate which are calculated with the molar weight of magnesium and phosphorus is (27-72):(0.5-1); the solution is precipitated after reaction for sufficient crystallization, and then crystal is precipitated and separated, thus a product can be obtained. The flame retardant has good dispersity in solution, and the thermogravimetric curve analysis shows that the flame retardant is wider in thermal decomposition range, faster to release water at high temperature than ordinary Mg(OH)2, capable of decomposing more water and good in flame retarding effect. The preparation method is simple, moderate in reaction conditions, high in magnesium hydroxide, suitable for industrial production. **Modification method of nano-magnesium hydroxide CN101368009**The invention relates to a modification method of nano magnesium hydroxide, which comprises the following steps: nano magnesium hydroxide powder is added into deionized water to be prepared into slurry; the slurry is added into a container which is arranged in an ultrasonic trough and provided with a stirrer to be stirred and receives ultrasonic dispersing activation treatment; and then surface modifier is added in to continue the ultrasonic stirring modification; the modified magnesium hydroxide receives suction filtration and is washed, heated, dried, ground and screened to obtain surface modified magnesium hydroxide powder. The method really realizes the nano dispersion of nano particles in the solution and modifies the surface of the nano particles with the help of the multiple functions of ultrasonic cavitation to the dispersion and surface activation of the nano particles as well as the accelerated hydrolysis, accelerated polymerization and polycondensation reaction of the modifier. The surface modification is carried out at normal temperature, so that the process is simplified, the time is short, the efficiency is high and the energy consumption is greatly reduced; the prepared modified nano magnesium hydroxide powder has good dispersivity, and the size and distribution of the particles are even. **Preparation of nano magnesium hydrate CN101376511 T**he invention relates to a preparation method of nano-sized magnesium hydroxide, which is characterized in that a soluble magnesium salt solution and soluble lye which are added with a dispersant react in a reactor which is put in an ultrasonic tank and provided with a stirrer to obtain magnesium hydrate suspension; the magnesium hydrate suspension is processed through ultrasonic ageing at room temperature; the magnesium hydrate which is processed through ageing is dried through heating to obtain nano-sized magnesium hydroxide powders after being filtered and washed. The ultrasonic wave which is exerted during the reaction process promotes the nucleation, inhibits crystal nucleus growth velocity, and controls the size and the distribution of particles; the ultrasonic cavitation avoids the occurrence of aggregate phenomenon, and increases the uniformity and the dispersibility of nano particles; the thermal effect of the ultrasonic wave increases the crystallinity degree of the nano particles and shortens the ageing time of samples. Therefore, the preparation method has the advantages of simple technology, short production period, mild production conditions, good product dispersibility, and even particle distribution. **Method of preparing surface modified nano magnesium hydroxide CN101054190**A method for preparing surface modified nano-scaled Mg(OH)2 comprises the steps of: preparing the soluble magnesium salt into magnesium salt solution, preparing the surface modification agent and alkali into a mixed solution, dipping the magnesium salt solution into the mixed solution at the temperature of 20-100 degree, stirring strongly for 1-10H, cooling for 2-24H at room temperature, filtering and washing with de-ionized water till PH6-7, drying in vacuum oven and hence obtaining the surface modified nano-scaled Mg(OH)2. The invention is characterized in integral crystal shape of the sample during preparation, simple processing and soft reaction conditions etc. **Process for producing nano-flame-proof magnesium hydroxide CN101219801**The invention relates to a method for preparing nanometer flame-retardant-grade magnesium hydrate by using an impinging stream and through the surface modification. The main processes are: the magnesia ion solution obtained by means of the salt lake water chloromagnesite or impurity removal of concentrated brine after sea water desalinization is reacted with a sodium hydroxide to crystallize and couple to prepare nanometer magnesium hydrate; proper surface activator is selected to modify the nanometer magnesium hydrate, which can obtain acicular or flake magnesium hydrate of 10-20nm. The technological characteristics are: 1) the purity of the magnesium hydrate of which the material source is widely obtained can be above 98 percent; 2) by adopting a jet impinging stream reaction crystallizer, the reacting conditions such as impinging stream rate can be regulated to control granularity and the shape of the crystal; 3) the reacting condition is moderate and the selected surface modifier has no harm to environment. **Method for producing nano-magnesium hydroxide by using low-level magnesite CN101219800**The invention relates to a method for comprehensive utilizing low-taste magnesite, which belongs to a mineral process and environmental protection field. The magnesite powder is calcinated under a temperature ranging from 800 DEG C to 1200 DEG C to prepare magnesia; the magnesia is reacted with sulfuric acid or nitric acid to prepare dissolvable magnesium salt (magnesium sulfate or magnesium nitrate) and the pH value of the system is regulated to 3-9; the reacted slurry is filtered to get filtrate; the filtrate is reacted with alkali (sodium hydroxide or ammonia) and the technological condition is controlled to prepare the slurry of magnesium hydroxide with a granularity of nanometer and a shape of flake; nanometer magnesium hydroxide product is prepared by filtering, aging, drying and scattering the slurry. The filtrate and washings are substantially composed of sodium sulfate, sodium nitrate, ammonium sulfate or ammonium nitrate, from which products of the sodium sulfate, the sodium nitrate, the ammonium sulfate or the ammonium nitrate can be acquired after high efficient evaporation and drying process. **Method for preparing Nano anthoid magnesium hydroxide film in microcosmic appearance CN1958850**This invention discloses a method for preparing Mg (OH) 2 nanofilm with flower-like microstructure. The method comprises electrolyzing Mg (NO3)2 aqueous solution using ionic liquid as the additive by cathode electrodeposition to obtain Mg (OH) 2 nanofilm with flower-like microstructure. The Mg (NO3)2 concentration in the electrolyte is 0.01-0.1 mol/L. The ionic liquid (1-methyl-3-ethylimidazole ethylsulfate) content in the electrolyst is 2.5-30 mL/L. The method can obtain large-area Mg (OH) 2 nanofilms on different substrates, and has such advantages as easy operation, low energy consumption and low preparation temperature (room temperature). **Preparation of an aqueous suspension of surface-modified nanoparticles of metallic oxides DE102005046263**Preparation of an aqueous suspension of surface-modified nano-particles of a metallic oxide, a metal hydroxide and/or a metallic oxide hydroxide, where the metal is aluminum, magnesium, cerium, iron, titanium, zinc and zirconium, comprises mixing an aqueous solution of a metal salt with an aqueous solution of a polymer at a pH of 3-13 and at a temperature (T1) of 0-50[deg]C and precipitating the surface-modified nanoparticles of the metallic oxide, metal hydroxide and/or the metallic oxide hydroxide by heating the mixture at a temperature (T2) of 60-300[deg]C. Independent claims are included for: (1) a method for the production of a powdered surface-modified nanoparticles of metallic oxide, metal hydroxide and/or metallic oxide hydroxide, comprising mixing an aqueous solution of a metal salt with an aqueous solution of a polymer at a pH value of 3-13 and at a temperature (T1) of 0-50[deg]C, precipitating the surface-modified nano-particle of the metallic oxide, metal hydroxide and/or the metallic oxide hydroxide by heating the mixture at 60-300[deg]C, isolating the precipitated nanoparticles from the aqueous reaction mixture, and drying the nanoparticles; and (2) a powdered surface-modified nanoparticles of a metallic oxide, metal hydroxide, and/or a metallic oxide hydroxide, having a coating with polyasparaginic acid, with a BET surface area of 25-500 m2>/g. **Slice type nonporous nano magnesia and its preparation method CN1865139**This invention relates to a flaky imperforate nanometer magnesium oxide crystal and the preparation method thereof. The procedures comprise: add compounded high molecular surfactant comprising of water-soluble high molecular surfactant and ionic surfactant at weight ratio between 0.2:1 and 5:1 into the 40-70%(wt) magnesium solution at weight ratio of 1-3% of the total solution weight, add alkaline solution dropwise at 0-50Deg C, the sediment is processed by filtration, washing, vacuum-drying and abrasion to produce magnesium hydroxide pioneer body; conduct controlled calcining process by stepwise heating-up in air, followed by decreasing the temperature to the room temperature at less than 2Deg C/min, to obtain the nanometer magnesium oxide white powder product.; The magnesium oxide crystal has a hexangular flake shape, with 20-180 nm length or width and 3-25nm thickness, and can be used as raw material for producing high-density, imperforate and high-performance dense ceramics and thermostable and electrically insulating material, catalyst carrier, intensifier and flexibilizer of functional material, and additive of superconductive and disinfectant material. This method is characterized of simple process, environment-friendly, low-price and convenient raw material, and mass batch production. **Process for preparing magnesium hydroxide loose nano blocked flame retardant and products therefrom CN1667029**This invention relates to manufacturing method and product of magnesium hydroxide loosen nanometer particle block fire retardant, it belongs to unorganic chemical nanometer material manufacturing. The capability of nanometer particle surface adsorbability is used. During the preparation process, after it is coated by surface modifier, high speed exiguous air current bubble is added, and it is strongly gas charged, dispersed, isotroped and emulsified in order to make massive gas between the created nanometer capsule particles and form multi material, then magnesium hydroxide loosen nanometer particle block fire retardant is made. The equipment of this invention is simple, technique is fluency, and can be executed scale generation.; In bubble cap disc style agitator, material is water soluble salt or oxide of magnesium, precipitant is NH3A-A+/-H2O, NaOH or Ca(OH)2, surface modifier is at least one of fatty acid, poly unsaturated fatty acid and its salt, then magnesium hydroxide loosen nanometer particle block fire retardant is made after it is separated and purified. The magnesium hydroxide particle scale consisted has at least one dimension in 1~100nm extent in three space. **Method of preparing nanometer magnesium oxide using uniform precipitation-supercritical carbon dioxide drying method CN1597520**A process for preparing nano-magnesium oxide by uniform deposition-supercritical CO2 drying method includes such steps as preparing magnesium hydroxide deposit in aqueous solution by uniform deposition method, displacing water from the deposit by alcohol, removing alcohol from deposit by supercritical CO2 drying method, separating alcohol for recovering it, cyclic use of CO2, and calcining the dried magnesium hydroxide. **Preparation method of high purity nano-magnesium hydroxide CN1718542**A process for preparing high-purity nano-magnesium hydroxide from the magnesium hexaminochloride features use of liquid-phase alkali hydrolyzing method. **Synthesis method of magnesium hydroxide nano pipe CN1556034**A process for synthesizing the magnesium hydroxide nanotubes includes adding aqueous solution of ammonia to the solution of magnesium nitrate (or chloride), stirring to generate deposit, centrifugal washing until its pH value is neutral, dispersing the deposit in the solution of methanol or ethanol and water, adding inorganic salt chosen from potassium chloride, sodium chloride, sodium sulfate, potassium sulfide, potassium nitrate, sodium nitrate and their mixture, stirring, reacting at 200-250 deg.C for 15-24 hr in a sealed reactor, cooling, washing and drying. **Method for manufacturing nanometer magnesium hydroxide fire retardant CN1542036**The present invention relates to the making process of nano magnesium hydroxide fire retardant and belongs to physical chemical process for preparing compound. The process of the present invention features that under the action of polymer protectant, soluble magnesium salt and soluble alkali as material are produced into magnesium hydroxide powder through forced emulsification and precipitation in high shearing homogenizing emulsifier, filtering, washing and drying. The special high shearing homogenizing emulsifier is provided with motor, casing, stator, rotor, liquid flow guide unit and other parts, and has rotation speed regulated based on the grain size of the product. The magnesium hydroxide product has grain size of 5-200 nm, high purity and excellent fire retarding performance. **PROCESS FOR PRODUCING NANO-SIZED HYDROTALCITE KEEPING ANION EXCHANGE ABILITY AND ANION REMOVING ABILITY KR20050010610**PURPOSE: A process is provided to produce a nano-sized hydrotalcite keeping an anion exchange ability and an anion removing ability, which is a layered double hydroxide(LDH) comprising Mg and Al and can be used as a filler in fiber or a polymer to remove anions. CONSTITUTION: The process contains the steps of: reacting an acid reactant and a base reactant under the condition of pH 8.5-12; aging the resultant in a constant temperature stirrer of 25-200deg.C; recovering the solid phase hydrotalcite from the aged resultant. The acid reactant comprises a magnesium source, selected from the group consisting of MgCl2, magnesium ethoxide, and Mg(OH)2, and an aluminum source, selected from the group consisting of Al(acac), aluminum tri-secbutoxide, and Al(OH)3, wherein the cation molar ratio( GBP Mg2 not +A|/ GBP Al3 not +A|) is 1-4.; And the base reactant contains NaOH and one or at least two selected from the group consisting of Na2CO3, Ca(OH)3, C8H6O4, NaHCO3, CO2, H3BO3, Na3PO4-12H2O, and Na2SiO3-9H2O. **Method for preparing composite microsphere of polymer-nano magnesium hydroxide CN1519262**A process for preparing the composite polymer-nano magnesium hydroxide microspheres includes sphericizing the magnesium hydroxide nanoparticles by use of polymer monomer, cross-linking agent and trigger, and the simulative emulsion polymerizing method and spray drying. Its advantages are high product performance in coated rate, quality, flame retarding, compatibility, etc. **Preparation method of nano-level magnesium hydroxide CN1513761**A process for preparing magnesium hydroxide nanoparticles by reverse deposition method features that the solution of magnesium salt is used as its raw material, the sodium hydroxide and ammonia water are used as mixed precipitant, and the crystal growth mechanism is used to control the granularity. Its advantages are simple equipment, high purity, low cost and (30-100)-nm diameter. **Method for preparing nano magnesium oxide CN1508072**The method for preparing nano-grade magnesium oxide is characterized by that it uses soluble magnesium salt, sodium hydroxide and basic magnesium carbonate precipitant as raw material, firstly the basic magnesium carbonate precursor is prepared, then said precursor is undergone the process of programmed heating and roasting treatment so as to obtain the invented nano-grade magnesium oxide powder body whose grain size is 7-100 nm, distribution is narrow, dispersivity is good and purity is high. **Prepn of nanometer-sized magnesium hydroxide CN1361062**The present invention is preparation of nano-sized magnesium hydroxide. It the liquid-liquid two-phase coprecipitation reaction of magnesium salt and alkali liquid in an all backmixing liquid membrane reactor, the nucleation and the crystallization are performed separated in the controlled nucleation and the crystallization conditions. The present invention can overcome the demerits of available technology, and produce magnesium hydroxide powder in nano size and with homogeneously distributed size. **Acidular or flaky nano magnesium hydroxide and its preparing process CN1359853**A process for preparing acicular or flaky nano magnesium hydroxide cystal used as additive of flame retarding agent or for preparing nano magnesium oxide includes such steps as adding surfactant to the aqueous solution containing Mg ions, stirring, adding alkali solution dropwise at 10-60 deg.C, and precipitation. Its advantages are simple process, low cost and continuous production. ---