| 摘要 |
Process for the preparation of at least one boric oxide, in the anhydrous or hydrated form, of general formula B2O3.xH2O, in which x is a number from 0 to 3, by hydrolysis of methyl borate, in which methyl borate and water are introduced, into a hydrolysis region, in a molar ratio of at least 1.3 mol of water per mole of methyl borate, then the product resulting from the hydrolysis region, at least one compound (preferably a hydrocarbon such as, for example, 2,3-dimethylbutane or 2-methylpentane) which forms a heteroazeotrope with methanol, the said heteroazeotrope having a boiling point below that of the azeotrope which methyl borate forms with methanol, and at least one compound (preferably a hydrocarbon such as, for example, cyclohexane or a saturated hydrocarbon having from 7 to 20 carbon atoms in its molecule) having a boiling point greater than that of methyl borate, the said compound not forming an azeotrope with a boiling point below that of the said heteroazeotrope, are introduced into a distillation column and then the said heteroazeotrope is recovered at the head of the column and a suspension containing at least one boric oxide is recovered at the bottom of the column.
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