| 摘要 |
<p>New K perborate hydrate (I) is of empirical formula - KBO3.nH2O - (n = 0-1). - (I) is pref. the monohydrate, with n = 0.05-1 (0.20-0.95), esp. 1 or 0. - (I) monohydrate is prepd. by reacting H2O2 with K metaborate (II) in a mixt. contg. a stoichiometric excess of K ions and sepg. (I) from the mother liquor. The mixt. in the reaction zone contains 70-150, pref. 80-110 g/l H2O2, 10-400, pref. 30-200 mole % excess of K ions and 70-180, pref. 80-120 g/l B2O3. The stoichiometric excess is produced (in part) by adding a soluble K salt, pref. K sulphate and/or KCl. Reaction is pref. carried out for 0.5-4 (1-3) h at 0-30 (0-20) deg.C. The reaction can be carried out continuously by charging the reaction zone with H2O2, (II) soln., soluble K salt, if necessary, and (part of) the mother liquor from the second stage. (I) with n = less than 1 is prepd. by dehydrating the monohydrate.</p> |
