TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: In the method, all the glycerol layers are collected and treated with SOx or flue gas to convert the spent KOH catalyst into K2SO4 or K2CO3 respectively; the pH of the glycerol layers is then adjusted and the methanol distilled off; the remaining hot mass is centrifuged to separate out potassium salt from glycerol; the potassium salt is washed to remove adhering impurities; the glycerol is recycled for washing of fatty acid methyl ester layer of subsequent batches and/or distilled to produce refined, neat glycerol. The average yield of oil mechanically expelled from whole seeds of Jatropha curcas is 20 - 30 wt./wt.%. The oil was treated with 5 N caustic soda solution (0.7 - 1 equivalents, with respect to FFA, depending on the initial FFA of the oil), so as to yield neutralized oil having FFA of 0.25 - 0.35 wt./wt.%. The phospholipids and other impurities and coloring matter in the oil are removed by the neutralization. The obtained soap cake contains residual oil (10 - 30%) and is converted to a laundry bar by treating with additional quantity of alkali and other laundry bar ingredients. The moisture content of neutralized oil is reduced from ca. 0.1 - 0.01% by sparging with dry air after addition of the antioxidant (30 - 50 ppm). The methanolic KOH is treated with stoichiometric quantity with respect to KOH of anhydrous sodium sulfate to trap any water formed from reaction of the alkali with alcohol. The oil is transesterified with methanolic KOH in two stages, and in a single stage using methanol (ca. 1.5 - 2 equivalents) and alkali (preferably 1.5 - 2 wt./wt.% of KOH with respect to the neutralized oil is used). The crude methyl ester layer after removal of glycerol layer is treated with 1 - 10% additional quantity of glycerol to mop up remaining impurities in the methyl ester layer in order to prevent run off in aqueous stream when the methyl ester layer is washed with two lots of water having less than 50 ppm total dissolved solid (TDS). A part of the first lot of wash water in an amount of 0.5 - 1 l/l of biodiesel, and containing 25000 - 35000 ppm chemical oxygen demand (COD) is converted to caustic lye for use in neutralization or laundry bar preparation from soap cake and the rest is treated before discharge. The second lot of wash water out of two washes containing 500 - 2000 ppm COD is used for the first water wash in a subsequent batch. The resultant methyl ester is treated with 5 - 50 ppm of antioxidant that comprises BHT, and then sparged with dry air to reduce moisture content to less than 500 ppm. A substantial portion of the KOH catalyst is confined in the glycerol layer and is treated with stoichiometric quantity of concentrated sulfuric acid or SOx fumes or flue gases to convert the spent catalyst into potassic fertilizer in 95 - 100% yield for direct application. A part of the crude glycerol after removal of spent alkali catalyst and methanol is recycled for washing of the crude methyl ester of subsequent batch. The method further involves distillation of remaining glycerol having minimum water content to obtain neat, refined glycerol in 85 - 95% yield.Preferred Components: The triglyceride oil is obtained from Jatropha curcas. The oil cake contains 5 - 10% oil and is ground for subsequent use as organic manure. The free fatty acid content of the freshly expelled oil is 1.5 - 10 wt./wt.%.