Pure gold dissolution with hydrogen peroxide as the oxidizer in HBr or HI solution
作者:Masashi Hojo、Shunsuke Iwasaki、Kei Okamura
DOI:10.1016/j.molliq.2017.09.080
日期:2017.11
influences of “indifferent” salts or supporting electrolytes, LiCO4, NaClO4, or Mg(ClO4)2 on the log (k/s− 1) value have been very small. Contrastingly, the log (k/s− 1) value of − 4.22 in 2.0 mol dm− 3 HNO3 (as the oxidizer) solution containing 2.0 mol dm− 3 NaCl at 50 °C has been accelerated remarkably with increasing electrolyte concentrations, e.g., Δlog (k/s− 1) = 0.66 (ca. 4.5 times) at 1.0 mol dm− 3 Mg(ClO4)2
在35°C的HBr或HI存在下,已探索了H 2 O 2作为氧化剂的纯金溶解情况,并作为参考,研究了含NaCl的稀HNO 3系统的纯金溶解情况。已发现具有0.2–2.0 mol dm − 3 HBr的0.02–0.2 mol dm − 3 H 2 O 2溶液为溶解纯金线提供了有效的介质(99.95%,直径0.25 mm,约20 mg)在20 mL反应容器中:随着H 2 O 2浓度的增加,溶出速率常数log(k / s − 1)从− 6.17增至− 3.33和HBr。“无差别”的盐或辅助电解质,LiCO 4,NaClO 4或Mg(ClO 4)2对log(k / s -1)值的影响很小。相反,随着电解质浓度的增加,例如在2.0 mol dm -3 HNO 3(作为氧化剂)溶液中含有2.0 mol dm -3 NaCl的2.0 mol dm -3 HNO 3(在氧化剂中)的log(k / s -1