| 摘要 |
The present invention relates to a process method for extracting magnesium and lithium from a brine and coproducing hydrotalcite. The method comprises the following specific steps: adding an aluminum salt to a brine so as to prepare a mixed salt solution A used for preparing a magnesium-aluminum hydrotalcite, adding an alkaline solution, performing a coprecipitation reaction and then performing a crystallization reaction, and after the completion of the reaction, performing solid-liquid separation to obtain an MgAl-LDH solid product and a filtrate; evaporating and concentrating the filtrate to obtain a lithium-rich brine, then adding an aluminum salt to prepare a mixed salt solution B used for preparing a lithium-aluminum hydrotalcite, adding same to an alkaline solution so as to perform a precipitation reaction, and after the completion of the reaction, performing solid-liquid separation to obtain an LiAl-LDH solid product and a filtrate; and evaporating and concentrating the filtrate, and returning the solution obtained after the evaporation and concentration to the lithium-rich brine for recycling. In the method of the present invention, the reaction is mild, the equipment is simple, the loss amount of lithium is small, and not only the resource separation of a salt lake can be realized, but also a functional material having a high additional value can be obtained. |
