Aromatic Polyisobutylene Succinimides as Viscosity Reducers with Asphaltene Dispersion Capability for Heavy and Extra-Heavy Crude Oils

Abstract

Four aromatic polyisobutylene succinimides were synthesized and evaluated as viscosity reducers for heavy and extra-heavy Mexican crude oils. Because of the asphaltenic character of Mexican crude oils, aromatic heads capable of interacting with asphaltene aggregates by π–π stacking, hydrogen-bond formation, and acid–base interactions were selected. Asphaltene dispersion–aggregate inhibition and asphaltene disaggregation effects were evaluated as promoters of the viscosity reduction effect in asphaltenic crude oils, the asphaltene disaggregation being dominant. Chemical compounds show good efficiency as asphaltene aggregation inhibitors and dispersants and as viscosity reducers. Higher efficiency than the dilution effect induced by the solvent carrier is observed. Both experiments were studied by theoretical DFT calculations. Because of the agreement between theoretical and experimental results, both mechanisms can be elucidated. Results also show that the initial asphaltene content in oils is an important parameter in the selection of chemical agents as viscosity reducers.

Multifunctional Evaluation of a New Supramolecular Complex in Enhanced Oil Recovery, Removal/Control of Organic Damage, and Heavy Crude Oil Viscosity Reduction

“…High viscosity of the heavy oil sample of TC system used in the rheological experiments can be attributed to its high content of heavy organic compounds such as resins and asphaltenes (33.79 and 21.86 % respectively), as reported 37 . In fact, as it has been observed, at asphaltene concentrations above of 10 %, the crude oil behaves like a concentrated system where the viscosity increases dramatically because of the entanglement of the asphaltene aggregates in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 the media [37][38] .…”

“…In fact, as it has been observed, at asphaltene concentrations above of 10 %, the crude oil behaves like a concentrated system where the viscosity increases dramatically because of the entanglement of the asphaltene aggregates in 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 the media [37][38] . The effect of the supramolecular complex on the rheological behavior of heavy crude oil of TC system at different temperatures is shown in Figure 14.…”

Effect of Water on Deposition, Aggregate Size, and Viscosity of Asphaltenes

“…The reduction in the viscosity can be indicative of smaller asphaltene aggregates. 9 The increase in the viscosity may be also explained as the structural changes induced by the excess of water molecules. There may be also emulsion formation, which could cause larger asphaltene aggregates.…”

Synthesis, characterization, and evaluation of polyisobutylene‐based imido‐amine‐type dispersants containing exclusively non‐nucleophilic nitrogen

“…Scheme shows the various representative dispersants of this family and the PIB intermediates from which they are derived. The polar head‐group of these dispersants include aromatic moieties, which are anticipated to undergo π–π stacking with the polyaromatic hydrocarbon surface of soot . We also report herein on the effect of the number of end‐group phenyl rings on the adsorption of the dispersants onto the surface of carbon black and the performance properties of a representative non‐nucleophilic dispersant containing phthalimide as the aromatic moiety.…”