An automatic flow-batch standard-addition method for sodium determination in alcohol fuel by flame photometry

Journal of the Brazilian Chemical Society

Almeida, Luciano F. de¹  Moreira, Pablo N. T.¹  Araujo, Mario Cesar U.¹  Silva, Edvan C. da¹  Universidade Federal da Paraíba¹  Martins, Valdomiro L.¹ 

关键词: standard-addition method;    flow-batch system;    sodium determination;    alcohol fuel;    flame photometry;   

DOI  :  10.1590/S0103-50532003000200010

学科分类：化学（综合）

来源: SciELO

【 摘 要 】

The Brazilian Regulatory Agency for fuel production and commercialization requires that the sodium concentration in alcohol fuel should be determined by flame photometry and that the analytical curves should be obtained with matrix-matched standards. Notwithstanding, this methodology can produce inexact results because alcohol fuel presents a significant variability in matrix composition and, consequently, in the matrix effect. This problem can be circumvented by using the standard addition method (SAM). However, this method is slow and laborious when it carried out by manual procedures. To overcome these drawbacks, an automatic flow-batch SAM for sodium determination in alcohol fuel by flame photometry is described. This system requires only one standard solution, handles about 80 – 140 samples per hour and consumes a total volume of sample and of standard solution smaller than 1.5 mL for each analysis. The results present a standard deviation usually less than 0.1 mg L-1 (n = 4).

【 授权许可】

Unknown