Ferreira Ramon S B, de Souza Patrícia T, Gonçalves Daniel, Dos Passos Rafaela M, Sampaio Klicia Araujo, Meirelles Antonio J A, Caldas Batista Eduardo A
Laboratory of Extraction, Applied Thermodynamics, and Equilibrium (EXTRAE), School of Food Engineering (FEA), University of Campinas (UNICAMP), 80 Monteiro Lobato St., 13083-062 Campinas, SP, Brazil.
ACS Omega. 2025 Jul 10;10(28):30222-30231. doi: 10.1021/acsomega.5c01406. eCollection 2025 Jul 22.
The amounts of glycerol and ethanol in purified biodiesel are standardized by regulatory agencies to ensure the performance of the biofuel in combustion. Therefore, the correct measurement of these components is essential to evaluate the final quality of biodiesel and to monitor its synthesis. In addition, evaluation of the composition in ethanol and glycerol is also relevant in modeling the kinetics of the transesterification reaction. Ion chromatography was evaluated as an alternative technique to identify and quantify ethanol and free glycerol in biodiesel samples from heterogeneous, homogeneous, and enzymatic catalysis. The analytical method exhibited detection limits of 0.1 and 0.94 mg·L and quantification limits of 0.3 and 2.83 mg·L for glycerol and ethanol, respectively. Additionally, the analytical method demonstrated suitable repeatability (RSD = 0.14% and RSD = 0.80%), reproducibility (RSD = 1.27% and RSD = 3.32%), and selectivity, proving to be reliable in relation to the matrix effects according to the validation guide of the Association of Official Analytical Chemists (AOAC). Ion chromatography has been demonstrated to be an alternative technique that is adequate for the quantification of ethanol and glycerol in different alkyl ester systems. Moreover, the technique dispenses the use of organic solvents, resulting in a considerable reduction of toxicity, analysis time, and analytical costs, and contributes to both environmental and operational securities.
监管机构对纯化生物柴油中的甘油和乙醇含量进行了标准化，以确保生物燃料在燃烧中的性能。因此，正确测量这些成分对于评估生物柴油的最终质量和监测其合成至关重要。此外，评估乙醇和甘油的组成对于模拟酯交换反应的动力学也很重要。离子色谱法被评估为一种替代技术，用于鉴定和定量来自非均相、均相和酶催化的生物柴油样品中的乙醇和游离甘油。该分析方法对甘油和乙醇的检测限分别为0.1和0.94 mg·L，定量限分别为0.3和2.83 mg·L。此外，该分析方法具有良好的重复性（RSD = 0.14%和RSD = 0.80%）、再现性（RSD = 1.27%和RSD = 3.32%）和选择性，根据官方分析化学家协会（AOAC）的验证指南，在基质效应方面被证明是可靠的。离子色谱法已被证明是一种适用于定量不同烷基酯体系中乙醇和甘油的替代技术。此外，该技术无需使用有机溶剂，从而大大降低了毒性、分析时间和分析成本，并有助于环境和操作安全。
