土壤中碘含量的测定方法

Determination of Iodine Content in Soil

目的探讨土壤中碘经艾氏试剂混合灼烧试样,砷铈氧化还原分光光度法测定碘含量的方法。方法土壤经自然风干,粉碎过100目筛,取适量试样于盛有0.5 g艾氏试剂的瓷坩埚中,再取2 g艾氏试剂覆盖试样,置高温炉中灼烧,冷却,水浸提,砷铈氧化还原分光光度法测定碘含量。结果试样灼烧最佳温度750℃,时间为1h,回收率范围为92%～103%,相对标准偏差(RSD)为1.71%。结论采用艾氏试剂技术,砷铈氧化还原分光光度法测定碘含量,方法简便、快速、准确、重复性好。

[ Objective ] To investigate the determination of iodine content in soil by arsenic-cerium redox spectrophotometry with soil sample and Aldrin reagents incineration. [ Methods ] Soil was air-dried, grinded, and screened through 100 mesh sieve. Appropriate sample was put in porcelain crucible with 0.5 g Aldrin reagents, and another 2 g Aldrin was used to cover the sample. Then the mixture was burned, cooled off, lixiviated by water, and determined by arsenic-cerium redox spectrophotometry. [ Results] The optimum temperature for burning sample was 750℃, optimum time was 1 hour, recovery range was 92% - 103%, relative standard deviation （RSD） was 1.71%. [ Conclusion ] Adopting Aldrin reagents, arsenic cerium-redox spectrophotometry for determination iodine content in soil is simple, rapid, accurate, and reproducible.