利用含碘废液制备碘化钾的实验研究

以“化学反应速度与活化能”实验产生的含碘废液为研究对象,分析了废液中碘的存在形式及碘的含量,提出了利用含碘废液制备碘化钾的方法。首先利用CuSO4沉淀废液中的碘,得到CuI,加入Fe粉发生置换反应后,再加入K2CO3溶液即可反应得到KI。该法对废液中碘的回收率为80.5%,制备碘化钾的纯度为98.7%,可作为常规化学试剂使用。本实验可以作为本科生的开放实验,有助于培养学生的创新思维,增强环保意识。制备的KI可以重新作为学生实验的原材料,做到了废物的循环利用,符合绿色化学实验的要求。

Experimental study on the preparation of potassium iodide from waste liquid containing iodine

The waste liquid containing iodine produced by the experiment of ＂ Chemical reaction speed and activation energy＂ was explored in this study. The forms and the content of the iodine from waste liquid containing iodine were analyzed. A method of potassium iodide preparation using waste solution was proposed. Firstly,CuSO4 was added to the waste liquid containing iodine and CuI deposition was obtained. Secondly,iron powder was added to he solution and replacement reaction occurred. After completion of reaction,potassium carbonate added to the filtered solution,and KI can be produced. The recovery rate of iodine of this method was 80. 5%. The purity of KI by this method was 98. 7% which can be used as regular chemical reagent. This experiment can be conducted as the opening experiment for the undergraduates,helping to cultivate students＇ innovative thinking,improving their awareness of environmental protection. The potassium iodide can be reused as raw material of teaching experiment,which will achieve the recycling of waste and meet the requirements of green chemistry experiment.