Rapid and sensitive method for the determination of acetaldehyde in fuel ethanol by high-performance liquid chromatography with UV-Vis detection.
A high-performance liquid chromatography (HPLC) method for the determination of acetaldehyde in fuel ethanol was developed. Acetaldehyde was derivatized with 0.900 mL 2,4-dinitrophenylhydrazine (DNPHi) reagent and 50 microL phosphoric acid 1 mol L(-1) at a controlled room temperature of 15 degrees C for 20 min. The separation of acetaldehyde-DNPH (ADNPH) was carried out on a Shimadzu Shim-pack C18 column, using methanol/LiCl((aq)) 1.0 mM (80/20, v/v) as a mobile phase under isocratic elution and UV-Vis detection at 365 nm. The standard curve of ADNPH was linear in the range 3-300 mg L(-1) per injection (20 microL) and the limit of detection (LOD) for acetaldehyde was 2.03 microg L(-1), with a correlation coefficient greater than 0.999 and a precision (relative standard deviation, RSD) of 5.6% (n = 5). Recovery studies were performed by fortifying fuel samples with acetaldehyde at various concentrations and the results were in the range 98.7-102%, with a coefficient of variation (CV) from 0.2% to 7.2%. Several fuel samples collected from various gas stations were analyzed and the method was successfully applied to the analysis of acetaldehyde in fuel ethanol samples.
Saczk
Adelir Aparecida
AA
UNESP, Instituto de Química, Rua Prof. Francisco Degni s/n, Quitandinha, 14800-900 Araraquara, SP, Brazil.
Okumura
Leonardo Luiz
LL
Firmino de Oliveira
Marcelo
M
Boldrin Zanoni
Maria Valnice
MV
Ramos Stradiotto
Nelson
N