Kinetics of biofuel generation from deodorizer distillates derived from the physical refining of olive oil and squalene recovery

The recovery of squalene from deodorizer distillate derived from the physical refining of olive oil was evaluated by combining pressurized acidic esterification in a closed system with vacuum distillation. Esterification was carried out at 341, 359, 366, 391 and 395 K. The reaction at 395 K was found to be satisfactory as it decreased the acid value by 99.21% and generated a FAME concentration of 67.53% within 1 h. In order to demonstrate that the generation of FAME from deodorizer distillate was mainly due to the transformation of FFA, the reaction extent, which characterizes the reaction and simplifies calculations, was evaluated for FFA removal and the generation of FAME. Subsequent vacuum distillation allowed the separation of one fraction rich in FAME (94%), which can be used as a biofuel and accounted for 85% of the initial mass, and another fraction that was rich in squalene (78%) and may be used for manufacturing pharmaceutical products. The global squalene yield was 117 g kg−1 initial deodorizer distillate. •Evaluation of squalene recovery from the waste derived from the physical refining of olive oil.•The combination of esterification with distillation allowed the obtention of FAME and squalene.•Reaction extent was used as variable to quantify the esterification evolution in a closed system.•Biofuel with 94% FAME content accounted for 85% of the initial deodorizer distillate mass.•Squalene was concentrated until reaching a percentage of 78%.