Review of Microscale Dynamics of Dilution-Induced Asphaltene Precipitation under Controlled Mixing Conditions

Meng, Jia; Sontti, Somasekhara Goud; Zhang, Xuehua

doi:10.1021/acs.energyfuels.2c02815

Cited by 5 publications

(2 citation statements)

References 113 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The resin unit structure contains approximately five aromatic rings, while the asphaltene unit structure contains around seven to ten aromatic rings. The aromatic rings in asphaltene primarily undergo peri-condensation, while in resin, both peri-condensation and kata-condensation occur between aromatic rings [14][15][16].…”

Section: Introductionmentioning

confidence: 99%

The Neglected Role of Asphaltene in the Synthesis of Mesophase Pitch

Wang,

Li,

Wang

et al. 2024

Molecules

View full text Add to dashboard Cite

This study investigates the synthesis of mesophase pitch using low-cost fluid catalytic cracking (FCC) slurry and waste fluid asphaltene (WFA) as raw materials through the co-carbonization method. The resulting mesophase pitch product and its formation mechanism were thoroughly analyzed. Various characterization techniques, including polarizing microscopy, softening point measurement, Fourier-transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA), were employed to characterize and analyze the properties and structure of the mesophase pitch. The experimental results demonstrate that the optimal optical texture of the mesophase product is achieved under specific reaction conditions, including a temperature of 420 °C, pressure of 1 MPa, reaction time of 6 h, and the addition of 2% asphaltene. It was observed that a small amount of asphaltene contributes to the formation of mesophase pitch spheres, facilitating the development of the mesophase. However, excessive content of asphaltene may cover the surface of the mesophase spheres, impeding the contact between them and consequently compromising the optical texture of the mesophase pitch product. Furthermore, the inclusion of asphaltene promotes polymerization reactions in the system, leading to an increase in the average molecular weight of the mesophase pitch. Notably, when the amount of asphaltene added is 2%, the mesophase pitch demonstrates the lowest ID/IG value, indicating superior molecular orientation and larger graphite-like microcrystals. Additionally, researchers found that at this asphaltene concentration, the mesophase pitch exhibits the highest degree of order, as evidenced by the maximum diffraction angle (2θ) and stacking height (Lc) values, and the minimum d002 value. Moreover, the addition of asphaltene enhances the yield and aromaticity of the mesophase pitch and significantly improves the thermal stability of the resulting product.

show abstract

Section: Introductionmentioning

confidence: 99%

The Neglected Role of Asphaltene in the Synthesis of Mesophase Pitch

Wang,

Li,

Wang

et al. 2024

Molecules

View full text Add to dashboard Cite

show abstract

“…Asphaltenes, in their bulk form, are complex high-molecular-weight components of crude oil that exhibit limited solubility in aliphatic solvents such as heptane but are soluble in aromatic solvents like toluene. ,− The structure of bulk asphaltenes (BA) is characterized by an array of polycyclic aromatic rings, aliphatic side chains, and heteroatoms, such as sulfur, nitrogen, and oxygen with acidic and basic attributes. − These structural features may confer a polar nature to bulk asphaltenes . On the other hand, interfacially active asphaltenes, also known as interfacial material (IM), are a subfraction of BA that exhibit enhanced interfacial activity at liquid–liquid and liquid–solid interfaces. , Interfacially active asphaltenes have a slightly different molecular structure compared to their parent BA.…”

Section: Introductionmentioning

confidence: 99%

Mechanistic Investigation of Wettability Alteration by Bulk and Interfacial Asphaltenes Using a Surface Force Apparatus

Elkhatib,

Youssif,

Piri

et al. 2023

Energy Fuels

View full text Add to dashboard Cite

Asphaltenes play an important role in the wettability alteration of sedimentary rocks; however, the mechanisms of their interactions with mineral surfaces are still an open area of research. In this study, we used a surface force apparatus to probe the intermolecular forces between asphaltene samples and muscovite mica in aqueous media. The samples consisted of bulk asphaltenes (BA) precipitated from a Wyoming crude oil and their interfacial material (IM) subfraction. The impact of the monovalent salt concentration in water was first investigated at ambient conditions. We found that increasing sodium chloride (NaCl) concentration from 0 to 1 wt % resulted in a rise in the steric repulsive forces during the approach of BA and IM films toward a bare mica sheet. In other words, amply saline brines induced a higher salt−asphaltene binding tendency, leading to an increased brush extension and consequently a higher steric repulsion with mica. Forcing the BA into contact and breaking the thin water film on mica gave rise to an adhesive force that increased from 0.75 mN/m in distilled water to 35.1 mN/m in 1 wt % NaCl brine. Similarly, IM demonstrated an increasing repulsion with mica due to the rise in brine salinity, which induced tighter molecular packing with a grafting distance of 8.1 nm in distilled water and 6.4 nm in 1 wt % brine (compared to ∼2 m with BA). This behavior intensified the steric repulsion at the point of contact, and no adhesion of IM was observed on the mica surface under these conditions. To mitigate the adhesion of BA onto mica at high salinities, we explored for the first time the impact of different wettability modifiers on the intermolecular forces involved in these systems. Cationic surfactants such as dodecyl trimethylammonium bromide (DTAB) gradually reduced the adhesion forces from 35.1 to 0 mN/m after 24 h by progressively passivating the polar sites of BA and the negatively charged sites of mica. On the other hand, anionic nanoparticles such as graphene quantum dots (GQDs) instantaneously suppressed the adhesion of BA to mica by hydrogen bonding with the nitrogen heteroatoms of BA. The findings of this study shed some light onto the controlling parameters promoting the wettability alteration of mica by asphaltenes and highlighted the remarkable ability of GQDs to restore this wettability.

show abstract