Production of biolubricants from soybean oil: Studies for an integrated process with the current biodiesel industry

[Display omitted] •Potential biolubricants were synthesized from soybean fatty methyl esters.•Water, 2-ethylhexanol and their mixtures were studied as nucleophilic agent.•Bio-based lubricants were obtained with viscosities at 40 °C ranging from 26.6 to 99.6 cSt.•Process integration between a biodiesel plant and biolubricant production was evaluated.•An industrial process was proposed to obtain both biodiesel and biolubricants. The competitiveness of the biodiesel industry may be improved by adding value through co-products and integration with the oleochemical industry, especially for novel products such as biolubricants, a product of increasing world demand. In this study the synthesis of biolubricants from soybean oil was evaluated using transesterification, epoxidation and oxirane ring opening reactions. Water, 2-ethylhexanol and their mixtures were used to obtain hydroxyl-rich and/or ether-type branched molecules. All chemical modifications were monitored by Nuclear Magnetic Resonance (1H NMR) and evaluated through the physicochemical properties of the products. Several potential biolubricant samples were synthesized with viscosities at 40 °C ranging from 26.6 to 99.6 cSt, viscosity index from 26 to 139, densities at 20 °C from 0.925 to 0.964 g/cm3, and pour points from −3 to −12 °C. From these results, a proposal of a feasible industrial process for the production of biolubricants from soybean oil is presented, consisting of 16 units, of which 15 may be integrated with an existing biodiesel plant.