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Fish farming is a worldwide growing activity and a large amount of residues is produced in this process. The present work describes a cleaner and sustainable way to produce new lubricants from fish waste oil. Oil extracted from the Nile tilapia (Oreochromis niloticus) viscera was utilized as raw material to produce basic oil for lubricants. The products were synthesized by esterification with polyols, trimethylolpropane (TMP) and pentaerythritol (PE), using p‐toluenesulfonic acid (p‐TSA) as catalyst. The synthesized esters were characterized by infrared (IR) and nuclear magnetic resonance (NMR). Computational methods were used to predict the physical characteristics of the material. In addition, the main physicochemical properties were evaluated, as well as the thermal behavior and toxicity of the products against Artemia salina. The synthesized esters showed high viscosity indexes (VI > 150) and viscosities that fit the degree of application ISO‐46 and 150. Molecular dynamics simulations indicated that at room temperature the lubricants Tilapia fatty acid ‐ trimethylolpropane ester (T‐TMPE) and Tilapia fatty acid ‐ pentaerythritol ester (T‐PEE) are in liquid and gel states, respectively, confirming the experimental data. The products did not present toxicity against A. salina. In this research, we reinforce the potential of using tilapia oil from waste to produce green lubricants as a strategy to reduce damage to the environment, as well as the use of computational methods that collaborate to predict physical properties of lubricants. [ABSTRACT FROM AUTHOR]

• Deep Eutectic Solvents (DES) emerged, the class of compounds with essential properties in the industry. • Sn2+ and In3+ ions strongly interact with the chloride anion in DES. • In metallic mixture, the behavior of both ions in solvent remains unchanged. An alternative for replacing conventional organic solvents and ionic liquids, the Deep Eutectic Solvents (DES) emerged, a class of compounds with essential properties in the industry. These solvents have numerous advantages regarding ionic liquids, such as low price, biodegradability, and low toxicity. Furthermore, the DES has many applications in science, for example, organic synthesis, electrodeposition of metals, catalytic process. In this work, the behavior of Sn2+ and In3+ ions were analyzed in the solvents 1ChCl:2EG (chloride choline and ethylene glycol, DES) and water through computational simulations by molecular dynamics (MD) and Quantum Theory of Atoms in Molecules (QTAIM) calculations. The results showed that the Sn2+ and In3+ ions strongly interact with the chloride anion in DES. Furthermore, only the Sn2+ ion showed interaction with the ethylene glycol molecules in DES, which was not observed for In3+, which led to no interaction with EG. In contrast, the most likely interaction is between cations and oxygen from water in a water solvent. The analysis of Bond Critical Points (BCPs) showed that the strength of these interactions follows the following sequence: In-Ow > In-Cl > Sn-Ow > Sn-Cl. The behavior of both ions in the metallic mixture was invariant in DES and in water when compared to the same isolated ions. Furthermore, it may be observed that the increase in the number of water molecules in the systems containing water did not cause relevant changes. [ABSTRACT FROM AUTHOR]