Effect of Mixtures of Polysorbate 80 and Low Molecular Weight Alcohols on Density and $$^\circ $$API Gravity of Treated Venezuelan Extra Heavy Oil

Formulations of extra heavy oil with biocompatible polyethoxilated compounds have not received much attention. We investigate the behaviour of biocompatible mixtures in the treatment of Venezuelan extra heavy oil, using the non-ionic surfactant Polysorbate 80 (Tween 80) and low molecular weight linear n-alcohols with even and odd number of carbon atoms, in order to predict the best fit in the ethoxide—alcohol interaction. Venezuelan extra heavy oil was recovered from mixtures that contained water, NaCl, polysorbate 80, and n-alcohols ranging from 1 to 8 carbon atoms. The density, \(^\circ \)API gravity (American Petroleum Institute gravity), and other properties were measured and compared for the even and odd numbered n-alcohols. We found a significant difference in density and \(^\circ \)API gravity values in the treated and recovered extra heavy oil, for n-alcohols with even and odd number of carbons, in the presence of polysorbate 80. This finding suggests that the ether within the ethoxide-repeating units of polysorbate 80 is the hydrogen bond acceptor of the n-alcohol donor. However, this interaction is favoured for the even number alcohols that interact in an “in-frame” manner with the ethoxide. We propose the formation of a micellar nanoparticle that promotes the improvement of Venezuelan extra heavy oil.