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bioRxiv · 10.1101/2025.07.26.666956

PHYSICOCHEMICAL PROPERTIES OF ENHANCED AND RECOVERED VENEZUELAN CRUDE OIL TREATED WITH BIOCOMPATIBLE PHARMACEUTICAL FORMULATION: SIMULATION OF THE ROLE OF WATER AND IONIC CONTENT.

Oquendo, L. E.·Colina, J. G.·Lopez, A.·Fernandez, M.·Andrades, E.·Andrades, V.·Pacheco, E.·Grassi, H.
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Abstract

In this work, the hydrogen bonding interaction of water and ethanol with Polysorbate 80 (P-80, Tween 80) is simulated, in relation to its role in oil upgrading and recovery, using real theoretical and experimental studies. The theoretical physicochemical results obtained were compared with other experimental results derived from the treatment of improved and recovered oil after mixing Biocompatible Pharmaceutical Formulations (BPF) of these three compounds and oil produced in Venezuela. The Spartan 16 program was used to build the molecular structures and simulate the interactions with the semi-empirical PM3 method, to compare them with two real experiments. These two experiments were performed as follows: in the first, the mixture consists of a surfactant, (Z)-Sorbitan mono-9-octadecenoate poly(oxy-1,2-ethanediyl) or polyoxoethylene (20) sorbitan mono-oleate (Polysorbate 80), which is mixed with the hydrocarbon, and then completely fluidized with the addition of ethyl alcohol or ethanol.Water and ions (<100 ppm) present in this experiment are contained in oil and ethanol as contaminants (approximately 1.73-1.30% of total water). In the second experiment, the BPF ratios were 10:5:0.1:0.01 for oil:water with 17,800 ppm NaCl:P-80:ethanol (approximately 33.09% of total water and 1.78% w/v NaCl). The simulations were performed taking into account both real experiments. The simulated interactive products were characterized by the following parameters: energy, minimum conformational energy, solvation energy, aqueous energy, HOMO energy, LUMO energy, {Delta}E, dipole moment, polarizability, electrostatic potential map (EPM) and electron density.A theoretical parametric relationship (sio Index, "stability in oil Index") is developed to evaluate the stability of the molecular forms generated within the hydrocarbon. The following theoretical experiments were performed: First, successive interactions of water with P-80 from position 1 to position 21. Second, successive interactions from position 1 to position 21 of P-80 of water and ethanol, 1 to 1. Third, successive interactions with P-80 of 21 ethanol molecules on the final product of the first experiment. These theoretical results were compared with some experimental results obtained using Oil Mixtures. The results obtained and compared in both experimental series (theoretical and real) allow to distinguish the role of P-80, Ethanol, Water and ions for the improvement and recovery of the treated oil. It is concluded that the formulation that does not contain added water and sodium chloride is supposed to use the contaminating water present in the petroleum and the water contained in the ethanol (<5%).This formulation has very little effect on the resulting Density of the improved Oil, but it greatly decreases the resulting Viscosity in the Crude Oil. The formulation that contains more than 30% added Water decreases the Density while the Viscosity of the Crude Oil responds proportionally to the Water retained in it. This difference in the results could be interpreted as a different proportion and chemical composition as a consequence of a different structural relationship between these components and a different conformation of the nanoparticle generated within the Oil, in each case. In this sense, the hypothesis is established that there would be an intermediate molecular form that could improve both Viscosity and Density.

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Oquendo, L. E., Colina, J. G., Lopez, A., Fernandez, M., Andrades, E., Andrades, V., Pacheco, E., Grassi, H.. 2025-07-31. PHYSICOCHEMICAL PROPERTIES OF ENHANCED AND RECOVERED VENEZUELAN CRUDE OIL TREATED WITH BIOCOMPATIBLE PHARMACEUTICAL FORMULATION: SIMULATION OF THE ROLE OF WATER AND IONIC CONTENT.. https://doi.org/10.1101/2025.07.26.666956

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