倍数光度滴定法测定微量过氧化苯甲酰

MULTIPLICATION-PHOTOMETRIC TITRATION OF MICRO-AMOUNTS OF BENZOYL PEROXIDE

联合应用BPO与KIO3（在KI存在下）的倍增反应和光度滴定数据的二阶导数法处理，使面粉中微量BPO测定的灵敏度较常规碘量法提高了200倍，方法的检出限可达0.1mg·L^-1。在面粉实样分析中，测定结果的RSD值在1.3％～2.8％之间，加标回收率在98.6％～102.2％之间。提出的方法所得测定结果与国标法（GB／T18415—2001）所得结果一致。

By the combining application of the multiplication reaction between benzoyl peroxide （BPO） and potassium iodate in the presence of potassium iodide and of the 2 nd derivation in the photometric titration, the sensitivity of the conventional iodimetric determination of BPO in wheat flour was reported to be raised to about 200 times, and a detection limit of 0. 1 mg· L^-1 was acheved. In its application to the analysis of wheat flour samples, RSD＇s obtained were in the range of 1.3%-2. 8% and recoveries found were in the range from 98. 6%-102. 2%. Results obtained by the proposed method were found to be in consistency with those obtained by the GB standard method （GB/T 18415-2001）.