大修渣浸出液中氟离子快速测定方法研究

作为固体危险废物,电解铝大修渣浸出液中含有大量氟离子,其处理处置都需测定氟离子含量。目前,测定大修渣浸出液中氟离子含量的方法普遍采用的是GB 5086.1—1997《固体废物 浸出毒性浸出方法 翻转法》,耗时长、效率低。针对这一问题,提出了一种快速测定大修渣浸出液中氟离子含量的方法,即通过强化固液界面传质过程,促进大修渣中可溶性氟化物的固液转移,从而大大提高了检测效率,由18 h缩减至0.5 h。实验结果表明,大修渣氟离子浸出质量为9 000~70 000 mg/kg,相对标准偏差均小于5.0%,加标回收率为96.35%~108.8%,说明快速测定法测定结果稳定,准确性高,有望成为测定大修渣浸出液中氟离子含量的标准方法。

Research on rapid determination method of fluoride ion in leachate of overhaul residue

As solid hazardous waste,the leaching solution of electrolytic aluminum overhaul slag contains a large amount of fluoride ions,which should be determined for treatment and disposal.At present,the method for determining the fluoride ion content in the leaching solution of overhaul residues is generally adopted GB 5086.1—1997,namely,《Solid Waste Leaching Toxicity Leaching Method-Turnover Method》,which is time-consuming and low efficiency.In response to this problem,a method to quickly determine the fluoride ion content in the overhaul slag leachate was proposed.Through the enhancement of the solid-liquid interface mass transfer process to promote the solid-liquid transfer of soluble fluoride in the overhaul slag,thereby the detection efficiency was greatly improved and the time was reduced from 18 h to 0.5 h.The experimental results showed that the leaching quality of fluoride ion in the overhaul slag was in the range of 9 000 to 70 000 mg/kg,the relative standard deviation was less than 5.0%,and the recovery rate of standard addition was between 96.35% to 108.8%,indicating that the rapid determination method was stable and high accuracy,which was expected to become a standard method for determining the fluoride ion content in the leaching solution of overhaul residue.