57results about How to "Lower initial temperature" patented technology

The invention discloses a method for preparing high-purity lithium oxide from lithium carbonate. The method comprises the following steps: A, performing acidification neutralization, namely putting battery-grade lithium carbonate into a reaction container, adding concentrated nitric acid, dropwise adding lithium hydroxide and nitric acid, and controlling the pH value to 6-8; B, performing filtering decontamination, namely filtering a mixed solution, dropwise adding lithium hydroxide and nitric acid till the pH value is 11-13, filtering so as to obtain a secondary filtering solution, and dropwise adding lithium hydroxide and nitric acid into the secondary filtering solution till the pH value is 1-2 so as to obtain an adjusted solution; C, performing crystallization, separation and drying, namely performing evaporation crystallization on the adjusted solution, performing cooling centrifugal separation, and drying so as to obtain lithium nitrate; and D, performing high-temperature decomposition, namely putting the lithium nitrate into a decomposition furnace, vacuuming to minus 0.01MPa to minus 0.09MPa, rapidly heating to 500 DEG C within 2-3 hours, heating to 650-750 DEG C within 6-10 hours, keeping the temperature for 8-12 hours, and keeping a vacuum degree of minus 0.01MPa to minus 0.09MPa in the heating and temperature keeping process, thereby obtaining high-purity lithium oxide finally. The method disclosed by the invention is simple in process, low in cost of raw materials and the like, low in unit energy consumption, relatively thorough in decomposition, high in purity of the prepared lithium oxide, and high in production efficiency.