火焰原子吸收光谱法间接测定氯化石蜡中氯

Indirect determination of chlorine in chlorinated paraffin by flame atomic absorption spectrometry

以Na2CO3-MgO-KOH为灰化固定剂，灰化法处理氯化石蜡样品，加入过量Ag^＋沉淀Cl^-，通过火焰原子吸收光谱法测定银以间接测定氯。对测定条件、灰化固定剂的选择及线性范围进行了考察。在25mL溶液中，Cl^-的线性范围为0～3．5μmoL，方法用于氯化石蜡中氯的测定，结果与比浊法吻合，相对标准偏差为1．9％（n=6），加标回收率为96．7％～101．2％。

Through ashing method to treat sample of chlorinated paraffin, using the mixed reagent of Na2CO3-MgO-KOH as ashing fixative, adding excessive Ag^＋ for precipitation of Cl^- and determining Ag^＋ in the filtrate by flame atomic absorption spectrometry, chlorine was indirectly determined. The optimum conditions for determination, choice of ashing fixative and linear range were studied. In 25mL solution, the linear range of Cl^- was 0-3.5 μmol. The method has been applied to the determination of chlorine in chlorinated paraffin, and the results are good agreement with those of turbidimetry, with RSD of 1.9% （n=6）. The recoveries are over the range of 96.7%-101.2%.