摘要研究了用8-羟基喹啉-Mg(Ⅱ)共沉淀体系,以Mn(Ⅱ)为内标,快速共沉淀分离富集啤酒中的铜和铅,并用火焰原子吸收光谱(FAAS)测定的方法。共沉淀受pH值、载体镁和内标锰用量的影响。结果显示在pH为9的条件下,能够定量共沉淀试样中的铜和铅。当试液为100mL^-1。时,方法的检出限分别为铜6.28×10^-3μg·mL^-1,Pb2.26×10^-2μg·mL^-1回收率为97.6%~103.0%,基本消除了基体干扰,取得了较为满意的结果。该方法无需收集全部沉淀,与传统的共沉淀方法比较,克服了收集沉淀费时的缺点。方法快速、简便、重现性好。
A method was proposed for the determination of trace copper and lead in beer with flame atomic absorption spectrometry after preconcentration of copper and lead by rapid coprecipitation technique with 8-oxyquinoline-Mg( Ⅱ ) using manganese as an internal standard at pH 9. The standard addition recovery of lead is between 97.6%-103.0%. The detection limit is 6.28×10^-3μg·mL^-1 for copper and 2. 26×10^-2μg·mL^-1 for lead when the sample volume is 100 mL. The effect of matrix can be overcome by the method and the results are satisfying. The method proposed here is rapid and has good reproducibility.