Flow-Injection Pulsed-Amperometric Determination of Free Glycerol in Biodiesel at a Gold Electrode

• Published in: Electroanalysis (New York, N.Y.) Vol. 24; no. 5; pp. 1160 - 1163
• Main Authors: Barbosa, Tatielli G. G., Richter, Eduardo M., Muñoz, Rodrigo A. A.
• Format: Journal Article
• Language: English
• Published: Weinheim WILEY-VCH Verlag 01.05.2012; WILEY‐VCH Verlag
• Subjects: Biodiesel; Electrical measurements; Electrodes; Flow injection analysis; Glycerol; Glycerols; Gold; Gold electrode; Mathematical analysis; Passivation; Pulsed amperometry; Standard deviation
• ISSN: 1040-0397; 1521-4109
• DOI: 10.1002/elan.201100719

This work reports the highly‐sensitive amperometric determination of free glycerol in biodiesel at a gold electrode adapted in a flow‐injection analysis (FIA) cell. The amperometric method involved the continuous application of three sequential pulses to the working electrode (+250 mV, +700 mV, and −200 mV, for 100 ms each). This sequence of potential pulses eliminated electrode passivation and dramatically increased the analytical signal. The proposed FIA‐amperometric method presented low relative standard deviation between injections (1.5 %, n=15), high analytical frequency (85 h−1), satisfactory recovery values (93–118 %) for spiked samples, wide linear range (from 1 to 300 µmol L−1), and low detection limit (0.5 µmol L−1).