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Nowadays, great variety of chemical products is producing by biotechnology methods from vegetable renewable sources. One of the most in-demand products from them is lactic acid, which is the basic substance for producing of wide variety of valuable organic chemicals, such as lactic acid esters, lactide, polylactide, propylene glycol. Most resent bio-lactic acid technologies have a stage of separation lactic acid from fermentation broth by sedimentation insoluble salt – calcium lactate. Next step is calcium lactate acidifying with conversion to lactic acid. This stage results to production of great amount of calcium sulphate (gypsum) wastes, about 1 ton of wastes on 1 ton of lactic acid. Thus, the costs for the purification of lactic acid and waste disposal reach 50% of the product total cost price. To avoid this problem, new method of lactic acid separation in butyllactate form was developed, which includes esterification of ammonium lactate with butanol-1, and then purification of obtained ester by vacuum rectification. In addition, it is possible to recycle the evolved ammonia to fermentation step.