Determination of bromine, fluorine and iodine in mineral supplements using pyrohydrolysis for sample preparation

Journal of the Brazilian Chemical Society

Duarte, Fábio A.¹  Antes, Fabiane G.¹  Flores, Érico M. M.¹  Taflik, Ticiane¹  Universidade Federal do Rio Grande, Rio Grande, Brazil¹  Paniz, José N. G.¹  Flores, Éder L. M.¹  Universidade Tecnológica Federal do Paraná, Medianeira, Brazil¹  Dressler, Valderi L.¹  Universidade Federal de Santa Maria, Santa Maria, Brazil¹ 

关键词: pyrohydrolysis;    halogens determination;    mineral supplement;   

DOI  :  10.1590/S0103-50532012000300016

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

Pyrohydrolysis was employed for mineral supplements decomposition prior to F, Br and I determination. Fluoride determination was carried out by potentiometry using a fluoride-ion selective electrode, whereas Br and I were determined by inductively coupled plasma mass spectrometry. The main parameters that influence on pyrohydrolysis were investigated. After evaluation, the following conditions were established: reactor temperature of 1000 ºC during 10 min; sample plus accelerator mass ratio of 1 + 5 and carrier gas (air) flow rate of 200 mL min-1. The accuracy of the proposed method was evaluated by analyte recovery tests and analysis of certified reference materials of phosphate rock and soil. Commercial mineral supplement samples were analyzed. The limits of quantification were 16, 0.3 and 0.07 µg g-1 for F, Br and I, respectively. By using a relatively simple and low cost pyrohydrolysis system up to 5 samples can be processed per hour. The developed sample preparation procedure can be routinely employed for F, Br and I determination in mineral supplements.

【 授权许可】

Unknown