Síntese e caracterização de éstres lubrificantes a partir da modificação do óleo da mamona (Ricinus communis) e óleo das vísceras da tilápia (Oreochromis niloticus)

Abstract

The magnutide of environmental problems attract worldwide attention for the need of the development of green technologies. In this sense, the market for materials from biomass, such as biolubricants, is increasingly viable and attractive in terms of volume, return and economic profitability. In this perspective, considering the richness of raw materials and the high national potential in the leadership of this segment, the present work aimed the production and characterization of biolubricants from the chemical modification of castor oil (Ricinus comunis) and oil extracted from the viscera of Nile Tilapia (Oreochromis niloticus). The synthesis of biolubricants was carried out from three consecutive reaction steps: transesterification, epoxidation and ring opening reaction with different alcohols. The transesterification reaction was performed with methanol (1: 6), in the presence of 0.7% of the catalyst (KOH) for to obtain methyl esters with yields above 95.0%. The epoxidation reaction was developed at room temperature with peracid (in situ) under conditions of 1: 1: 4 (unsaturation/ formic acid/ H2O2), the conversions were greater than 80% with selectivity of up to 96% of epoxide. The ring opening reaction was performed using the acid catalyst PTSA (5.0% w/w) with different alcohols (isoamyl, hexanol and 2-ethylhexane) in a ratio of 1: 3. The different biolubricants obtained were characterized by 1 H and 13 C NMR, FTIR, TGA, as well as physicochemical tests. The results showed higher values of thermal stability, viscosity index and fluidity at negative temperatures of the biolubricants obtained compared to petroleum derived lubricant. Both the biolubricants derived from castor bean, as well as the biolubricants derived from Tilapia, presented different degrees of viscosity and applicability as base oil for varied formulations