Monitoring by 1H Nuclear Magnetic Resonance of the Glycerin Purification by Vacuum Distillation

Given the growth in biodiesel production and other biofuels, it involves large volumes of byproducts which aren't suitable for commercial use. We studied the glycerol purification by vacuum distillation of the glycerol rich phase in the mixture reaction at the end of the biodiesel production process. Since glycerin is one of those byproducts, useful and plentiful, therefore the options to purify this one and achieve its better trading benefit are interesting. The process was monitored by 1 H NMR and showed that by vacuum fractional distillation of the glycerin rich phase of the biodiesel production it was possible to obtain pure glycerin between 97.4% and 98.9% on dry basis with 49.0% yield. Vacuum distillation without fractionation was inconvenient because it generates thermal degradation of the material and causes the formation of foam which induces low yield of glycerin and hinders the operation progress.