Sterol glucosides cause precipitation problems in biodiesel, leading to fuel filter blockage.
Testing for sterol glucosides in biodiesel and biodiesel filter residues is essential for the investigation of biodiesel problems. Intertek has significant expertise in testing biodiesel and finding the root-cause of biodiesel fuel filter related problems.
LC-MS analysis for steryl glucosides:
The volatility of steryl glucosides is too low to be successfully eluted by GC, without derivatisation. They also have limited sensitivity with conventional HPLC detectors. LC-MS is the chromatographic technique of choice for sterol glucoside analysis. The analysis is carried out using a LC-MS-TOF analyser which gives the detection of low levels of both steryl glucosides and esterified steryl glucosides.
NMR analysis of steryl glucosides:
NMR provides a reliable, quantitative and comparatively rapid method of detection of sterols without the need for sample modification. The initial NMR analysis involves using sterol standards from which diagnostic 1H NMR peaks are determined. It is possible to identify sterol glucosides in various biodiesel problem samples, without chemical modification, using these diagnostic NMR peaks.