TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Process: In the process: at least 1, preferably 1.3-2 equivalents of alcohol is used, based on the moles of the starting triglycerides; a quantity of not lower than 20 wt.%, preferably higher than 25 wt.% of TMSCl is used, based on the starting triglycerides; the reaction is carried out at 50-120 degrees C for 6-16 hours under vigorous stirring; and at reaction completion, the mixture is allowed to decant to obtain two clearly distinct phases which can be easily separated to obtain an upper phase containing biodiesel and volatile by-products, and a lower phase comprising a mixture of glycerol and 1-chloro-2,3-propanediol ( alpha -monochlorohydrin). The upper phase is then distilled at reduced pressure for removing volatile by-products to obtain pure biodiesel. The volatile by-products are further subjected to fractional distillation to obtain hexamethyldisiloxane and a mixture of alcohol and alkyltrimethylsilylether. Preferred Components: The lower alkyl alcohol is methanol, ethanol or n-butanol. The starting triglycerides are: from vegetable and/or animal source; and virgin or exhausted vegetable oils. EXAMPLE - In a 25 ml screw-cap Sovirel (RTM: Pyrex glass) tube, sunflower oil (10 g) was added to methanol (1.64 g) and trimethylsilyl chloride (2.78 g) under nitrogen atmosphere. The resulting emulsion was allowed to react under continuous stirring at 60 degrees C for 8 hours, and then allowed to cool at room temperature. Two phases were immediately separated after ceasing the stirring. The upper phase, containing the methyl esters, was separated and heated under reduced pressure (2 mmHg) at 65 degrees C for 3 hours to obtain a pale yellow liquid containing fatty acid methyl esters i.e. biodiesel (99%). The lower phase was dissolved in methanol (5 ml) and neutralized with calcium carbonate (1 g). After filtration, the solution was concentrated to dryness under reduced pressure to obtain yellow oil containing glycerol (52%) and alpha -monochlorohydrin (48%).