| abstract |
Preparation provided herein includes at least Mg 2+ At least Fe 3+ , aluminium content less than 10000ppm, average crystalline size less than 20nm Mixed-metal compounds method, comprising the following steps: (a) is by Mg 2+ Salt and Fe 3+ Salt and Na 2 CO 3 Merge with NaOH to generate slurry, wherein the pH value of the slurry is maintained at 9.5 to 11, and wherein by than completing to provide the Na for excessive 0 to 4.0 mole needed for reacting 2 CO 3 (b) 0.03 to 1.6kW/m is being provided 3 Per unit volume power under conditions of (c) mixed to the slurry separate the mixed-metal compounds from the slurry, by obtain crude product (d) that dry solid content is at least 10 weight % by it is following it is any in a manner of the dry crude product (i) crude product be heated to not higher than 150 DEG C and be enough to provide the temperature of every kg dryed product 0.05 water evaporation rate to 1.5kg water per hour, or (H) exposure crude product 500 to carry out rapid draing to the water evaporation rate of 50000kg water per hour by every kg dryed product. |