Determination of sulfur in coal using direct solid sampling and high-resolution continuum source molecular absorption spectrometry of the CS molecule in a graphite furnace

TALANTA

卷:106

Article

Mior, Renata¹  Mores, Silvane¹  Welz, Bernhard^1,2  Carasek, Eduardo¹  de Andrade, Jailson B.² 

[1] Univ Fed Santa Catarina, Dept Quim, BR-88040900 Florianopolis, SC, Brazil

[2] Univ Fed Bahia, Inst Nacl Ciencia & Tecnol CNPq, INCT Energia & Ambiente, BR-40170115 Salvador, BA, Brazil

关键词: High-resolution continuum source molecular absorption spectrometry;    Coal analysis;    Sulfur determination;    Carbon monosulfide;    Direct solid sample analysis;   

DOI  :  10.1016/j.talanta.2013.01.004

来源: Elsevier

【 摘 要 】

An analytical method has been developed for the determination of sulfur in coal using direct solid sample analysis in a graphite tube furnace and high-resolution continuum source molecular absorption spectrometry (HR-CS GF MAS). The molecular absorbance of the carbon monosulfide molecule (CS), which is formed in the vaporization stage, has been measured using the rotational line at 258.033 nm. Several chemical modifiers were tested and Ru, applied as permanent modifier was chosen, because it exhibited the best performance. The optimum pyrolysis and vaporization temperatures were found to be 500 degrees C and 2200 degrees C, respectively. Aqueous standard solutions prepared from L-cysteine were used for calibration, as the linear regression obtained for this standard was not significantly different from that for a certified coal reference material (CRM) according to a Student t-test. The results obtained for sulfur in three coal CRM and six additional samples also showed no significant difference for the two calibration techniques according to the same statistical test. The sulfur concentration in the coal samples was found between 3.5 mg g(-1) and 33.7 mg g(-1) with a typical repeatability around 10%. The limit of detection for the direct analysis of solid coal samples was better than 0.1 mu g S. (C) 2013 Elsevier B.V. All rights reserved.

【 授权许可】

Free