260 Solution Extraction of Magnesium Chloride
(a) The magnesium chloride aqueous solution with a magnesium content of 50～120g/L is extracted with diisooctyl phosphate or 2-ethylhexyl ester extractant in countercurrent, and the extractant is diluted with isooctane or solvent oil sulfonated kerosene to The volume concentration of the organic phase is 10-50%, and the organic phase is saponified with 5-15M or solution according to the conventional method. The volume ratio of the two is 8-12:1, and the extraction ratio O/W is 1-2 , The number of extraction stages is 8-12, and the extraction time is 5-10 minutes. After extraction, a saturated organic phase containing magnesium and an aqueous phase are separated; b) Use a stripping agent to extract the saturated organic phase containing magnesium after extraction in item (a) Phase extraction, the stripping agent is prepared with methanol, ethanol, ethylene glycol, propanol, butanol, glycerol or any two or more of the above-mentioned mixtures in any ratio to prepare the organic phase for stripping with a concentration of 0.5-8M The ratio of the saturated organic phase to the back-extracted organic phase is 1 to 5, the number of back-extraction stages is 1 to 2, and the time is 5 to 8 minutes. After the back-extraction is separated, an anhydrous magnesium chloride alcohol solution is obtained. The organic phase after the back-extraction is saponified Recycle afterwards; c). Put the anhydrous magnesium chloride alcohol solution of item (b) into a closed reactor, and pass ammonia gas at a temperature of -10～50 ℃ and stir, the amount of ammonia gas flowing is the magnesium chloride alcohol solution The magnesium ion equivalent concentration is 8-12 times. After the precipitate is formed, it is filtered or centrifuged to separate the magnesium chloride precipitate and the alcohol solution, and then the precipitate is washed with ammonia-saturated methanol for 1 to 3 in a conventional method to obtain the hexaammonium magnesium chloride precipitate and the alcohol solution. Then wash the precipitate with ammonia-saturated methanol for 1 to 3 times according to the conventional method. The alcohol solution is separated and recovered by distillation and returned to the stripping, and the ammonia gas is returned to use; Dry under the vacuum condition of 0.05～-0.1Mpa or under the protection of inert gas at a temperature of 50～120℃ for 1～3 hours to obtain hexaammonium magnesium chloride; e) Finally, the hexaammonium magnesium chloride is under the protection of inert gas at 400～600℃ Heating and deamination is carried out at a temperature for 1 to 3 hours to obtain anhydrous magnesium chloride product with a purity of 99.3 to 99.5%.
In order to improve the hydraulic properties of the extraction process in modern metal extraction, a diluent with a small specific gravity, low viscosity and miscibility with the extractant is usually added. 260 mineral spirit thinner must have the characteristics of high flash point, non-volatile, non-corrosive and cheap. Another more important criterion for choosing a diluent is chemical inertness. Because of the high quality/price ratio of kerosene, it is the most commonly used diluent. However, general kerosene is prepared by distillation of crude oil according to the requirements of fuel oil, so it does not meet the technical requirements of hydrometallurgy. This kerosene is a mixture of paraffins, aromatics and naphthenes. Therefore, when analyzing the composition of kerosene, not only its physical properties, but also its chemical inertness and its behavior in the solvent extraction process must be tested. The stability of a mixture of hydrocarbons to chemical reagents depends on it having double bonds. In this way, it provides a preferential location for the oxidation reaction and even the fixation of radioactive elements. An important role of the diluent is to effectively improve the physical properties of the extracted organic phase, such as reducing the viscosity of the extractant to increase its fluidity, changing the density of the organic phase, and expanding the density difference between it and the water phase, which is conducive to the separation and clarification of the two phases. This requires the viscosity of the diluent itself to be small. In addition, the diluent used for extraction must have low volatility and high flash point, which can reduce volatile losses and prevent fires. ・
260 solvent oil is suitable for mining metal extraction and defoaming washing production
1. It is widely used in the extraction and smelting of rare earths and non-ferrous metals (including cobalt, nickel, gold, copper, manganese, vanadium, etc.);
2, used to clean mechanical parts and precision metal products as detergents, such as aluminum foil and various aluminum alloy products, to improve brightness;
3, used as a cooling cleaning agent for electric spark cutting, can keep the surface of the workpiece smooth and clean;
4. Instillation decomposition to carburize metal workpieces, which can improve the hardness and wear resistance of the surface of metal processing parts; as a textile printing and dyeing auxiliary, as a fuel for miner’s lamp lighting, as a spice extractant, and for preparing cosmetics;
5. Fuel used for lighting and various blowtorches, steam lamps, vaporizers and kerosene furnaces;
6. ??Solvents in rubber and pharmaceutical industries, ink thinners, and pyrolysis materials for organic chemicals;
7. Process oil for glass ceramic industry, aluminum plate rolling, chemical heat treatment of metal workpiece surface, etc.;
260# solvent oil is unique in the extraction and smelting of rare earths and non-ferrous metals: first, it has no mechanical impurities, is colorless and transparent, and relatively improves the purity of the extracted products; second, the content of aromatic hydrocarbons is low, and the volatility is particularly low, which is suitable for non-ferrous metal smelting The amount of additive used in the production process is greatly reduced, and compared with similar products, the amount of use can be reduced by 30% to 50%. Therefore, many rare earth smelting enterprises and non-ferrous metal smelting enterprises in Guangdong, Guangxi, Jiangsu, Hunan, Yunnan, Henan and other provinces and cities use this product, and it is well received and praised by users and manufacturers.