| 摘要 |
The invention is directed towards a process for the concentration of aqueous hydrogen peroxide, comprising discontinuous crystallisation. According to the invention, a cooling surface arranged in a crystallising vessel and first wetted with hydrogen peroxide is cooled at a high cooling rate, whereupon seed crystals form. The cooling rate is at least 1 K/s, preferably from 10 to 30 K/s. When the vessel has been filled with H2O2 starting material, the latter crystallises, starting from the seed crystals, and forms a crystal layer. When the mother liquor of lower H2O2 concentration has been discharged, there follows a sweating operation with a slow increase in temperature, as a result of which the H2O2 concentration in the crystal layer is increased further.
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