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

Journal of the Brazilian Chemical Society

Luciano F. De Almeida¹  Valdomiro L. Martins¹  Edvan C. Da Silva¹  Pablo N. T. Moreira¹  Mario Cesar U. Araujo¹ 

[1] ,Universidade Federal da Paraíba CCEN Departamento de Química

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

DOI  :  10.1590/S0103-50532003000200010

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】

CC BY   
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