White crystalline powder.Soluble in water, slightly soluble in alcohol.Can deteriorate by absorbing carbon dioxide from the air.Strongly alkaline.Does not burn, but is highly corrosive.Usually in the form of a monohydrate.It loses water of crystallization when the temperature is higher than 100°C, and lithium hydroxide produces lithium oxide and water vapor at about 1000°C.Lithium hydroxide monohydrate is one of the most important lithium compounds, mainly used in the production of lithium grease, but also used in the production of other lithium compounds, is an additive for alkaline battery electrolyte.The main raw materials for the production of lithium hydroxide monohydrate are lithium mica and lithium pyroxene.
Solubility of lithium hydroxide monohydrate in water
| 温度℃ | 0 | 10 | 20 | 30 | 40 | 50 | 60 | 70 | 80 | 90 | 100 |
| 溶解度g | 12.7 | 12.7 | 12.8 | 12.9 | 13 | 13.3 | 13.8 | 14.4 | 15.3 | 16.2 | 17.5 |
Process profile of monohydrate lithium hydroxide evaporation and crystallization system:
The boiling point of lithium hydroxide solution rises lower, the solution is strongly alkaline, there are bubbles generated during the evaporation process; monohydrate lithium hydroxide crystals require large particle size. Evaporation system can be based on the price of electricity and steam prices, monohydrate lithium hydroxide evaporation and crystallization can be used MVR evaporation and crystallization, or multi-effect evaporation and crystallization.
MVR evaporation crystallization process of lithium hydroxide monohydrate: raw material liquid through the raw material pump conveying through the condensate preheater, steam preheater preheating into the MVR forced circulation evaporation crystallizer, crystallizer material in the forced circulation pump, after the heater heated up and returned to the crystallizer flash evaporation.Crystallization of the finished liquid under the action of the elution leg by the crystallization of the discharge pump extracted, extracted slurry through the centrifuge centrifugal separation, separation of wet materials into the next process, the separation of the mother liquor part of the return to the evaporation crystallization system, part of the extracted return to the previous process.Crystallizer flash secondary steam through the secondary spray tower spray defoaming, compressed by the compressor to get superheated steam, superheated steam and then through the elimination of superheat to return to the heating chamber to heat the material, and the material after the heat transfer of condensate condensate into the condensate tank, and then by the condensate pump conveying preheated material into the next process.
Characterization of the lithium hydroxide evaporative crystallization process:
①Crystallizer do enlarge the design, increase the residence time of the crystallized material, so that the crystal particles grow as large as possible, and at the same time set up a defoaming device to reduce the alkaline material in the process of evaporation of the secondary steam of the mist froth entrainment;
② The crystallizer is designed with an elution leg to screen the crystal particles, large particles are discharged from the system for centrifugal separation, and small particles continue to grow in the crystallizer;
③ Evaporation and crystallization temperature selection of lower temperatures, to avoid a sudden drop in temperature in the discharge process to produce a large number of fine crystals, affecting product quality;
④ Set up the secondary steam washing tower to avoid the foam entering the compressor with the secondary steam and affecting the normal operation of the compressor. In order to avoid the cooling down of the washing liquid affecting the flow of the secondary steam, set up the washing liquid heater to keep the washing liquid at a certain temperature;
⑤ The system piping is designed to prevent clogging of the transistor piping, which may affect normal production.