| 摘要 |
<p>The cpd. is made by (a) reacting bismuth with HNO3 in wt. ratio 1:3, regulating the temp. to avoid release of NO and obtain a soln; (b) concentrating it to 50-70%; (c) adding water to produce a Bi(NO3)3 soln; (d) treating this with ammonia soln. to form a ppte; (e) washing with water to remove soluble salts; (f) adding 2-4 moles citric acid per mole Bi, and water; (g) heating to reflux; (h) standing for 0.5-3 hours; (i) cooling to 40 deg.C; (j) adding 7-12 moles ammonia soln and water; and (k) spray drying the colloidal soln to obtain the prod. as powder.</p> |
