A flow injection procedure based on solenoid micro-pumps for spectrophotometric determination of free glycerol in biodiesel

作者：Silva Sidnei G; Rocha Fabio R P^*

来源：Talanta, 2010, 83(2): 559-564.

DOI：10.1016/j.talanta.2010.09.061

• Flow analysis
• Multicommutation
• Solenoid micro-pumps
• Biodiesel
• Glycerol

A flow system designed with solenoid micro-pumps is proposed for fast and greener spectrophotometric determination of free glycerol in biodiesel. Glycerol was extracted from samples without using organic solvents. The determination involves glycerol oxidation by periodate, yielding formaldehyde followed by formation of the colored (3,5-diacetil-1,4-dihidrolutidine) product upon reaction with acetylacetone. The coefficient of variation, sampling rate and detection limit were estimated as 1.5% (20.0 mg L-1 glycerol, n =10), 34 h(-1), and 1.0 mg L-1 (99.7% confidence level), respectively. A linear response was observed from 5 to 50 mg L-1, with reagent consumption estimated as 345 mu g of KIO4 and 15 mg of acetylacetone per determination. The procedure was successfully applied to the analysis of biodiesel samples and the results agreed with the batch reference method at the 95% confidence level.

• 出版日期2010-12-15