Rodkey F L, Robertson R F
Clin Chem. 1978 Dec;24(12):2184-5.
Solutions of KCN in 0.1 mol/liter NaOH, stored for six months at 4 degrees C, were unchanged as determined by silver titration and color development with pyridine-pyrazalone reagent. At room temperature the cyanide concentration of such solutions decreased by 0.079% per day (half life = 880 days) and the extent of color development changed in direct proportion to the change in silver titer. Rubber stoppers adsorb (or dissolve) HCN when in contact with this gas. The cyanide tends to come out of the stopper long after the source of the gas is removed. Rubber stoppers and expired air contaminated by HCN must be carefully avoided during cyanide analysis. Expired air contains HCN, generally in larger amounts for persons who smoke.
0.1摩尔/升氢氧化钠中的氰化钾溶液,在4℃下储存六个月后,通过银滴定法和用吡啶 - 吡唑啉酮试剂显色测定,溶液未发生变化。在室温下,此类溶液的氰化物浓度每天降低0.079%(半衰期 = 880天),显色程度的变化与银滴定度的变化成正比。橡胶塞与这种气体接触时会吸附(或溶解)氰化氢。在气体源去除很久之后,氰化物仍倾向于从塞子中逸出。在氰化物分析过程中,必须小心避免使用橡胶塞和被氰化氢污染的呼出空气。呼出空气含有氰化氢,对于吸烟者来说,其含量通常更高。