Effect of asphaltene structure on its aggregation behavior in toluene-normal alkane mixtures

Hemmati-Sarapardeh, Abdolhossein; Ameli, Forough; Ahmadi, Mehdi; Dabir, Bahram; Mohammadi, Amir H.; Esfahanizadeh, Leila

doi:10.1016/j.molstruc.2020.128605

Cited by 37 publications

(19 citation statements)

References 55 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The literature supports these results and indicates that the aggregates’ size increases with a higher asphaltene concentration in the system Figure displays the micrographs of the mineral oil samples containing different gilsonite concentrations that explicitly show that the maximum size and number of the aggregates increase with more asphaltene in the mineral oil.…”

Section: Resultssupporting

confidence: 57%

“…Overall, the consensus is that the crude blend’s increased aromaticity lowers the emulsion stability, and the kinetic stability is often explained through a thermodynamical lens. − The colloidal modeling approach states that the asphaltenes and resins form aggregates, and the aggregates clump together, establishing micelles. These micelles cover the droplets’ interfacial area and stabilize the emulsions by steric hindrance primarily . Previous studies have demonstrated that asphaltene materials as hydrophilic functional groups could potentially produce aggregates at the oil–water interface and form viscoelastic interfacial films around the water droplets. − However, the mechanism and influencing factors are still not fully understood.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Role of Asphaltene in Stability of Water-in-Oil Model Emulsions: The Effects of Oil Composition and Size of the Aggregates and Droplets

Velayati

Nouri

2021

Energy Fuels

View full text Add to dashboard Cite

Water-in-oil (W/O) emulsions are the most common type of emulsions handled in petroleum processes. It is thought that the field emulsions are primarily stabilized by asphaltene–resin micelles, and several research studies have examined the stability mechanisms of asphaltene in crude emulsions. However, there are still plenty of research gaps and unanswered questions in this area due to the complexity of the problem and difficulty of access and crude emulsion processing. These challenges can be addressed by investigating the effect of asphaltene on model emulsions’ kinetic stability. This study introduces a model W/O emulsion prepared by a new stabilizer (gilsonite) that contains asphaltenes and resins in combination with a non-ionic surfactant (Span 83). The colloidal characterization of the asphaltene aggregates in the mineral oil and oil blend of toluene and mineral oil was carried out. The size of the asphaltene aggregates in the mineral oil was found to increase with the added gilsonite concentration because of asphaltene precipitation and the process of smaller aggregates clumping together, forming flocs. Gilsonite was also found to precipitate and stabilize the W/O emulsions with the mineral oil as the external phase where the asphaltene precipitation was the most severe. The emulsions’ least kinetic stability was measured when toluene was added in the oil blend (50% volume fraction), where 100% water phase separation was observed with 0.25% gilsonite concentration. However, the dilute emulsion (10% water content in the emulsion) samples with 25% toluene revealed higher stability in terms of water phase separation than the case with 12.5% toluene with 20.83% less water separation in a 3 day storage period. This observation contradicts the expected outcome in a thermodynamic perspective where the W/O emulsion stability is thought to be merely dependent on asphaltene precipitation. The dilute emulsion with 12.5% toluene contained asphaltene aggregates larger than the emulsion droplets, which cannot contribute to the stability process. The ratio of the mean aggregate size to the mean droplet size was 133% larger for the dilute emulsion with a smaller fraction of toluene in the oil blend for this case. Therefore, the aggregates’ size to droplet size misalignment resulted in less stability for this emulsion than for the emulsion with higher aromaticity of the oil blend despite the very high precipitation rate. This paper presents observations of the effects of the asphaltene precipitation rate, size of the aggregates, and size distribution of the emulsion droplets on the model W/O emulsions’ stability. The significance of the results is in revealing the importance of integrating the thermodynamical and colloidal viewpoints to describe the role of asphaltene in stabilizing emulsions. This approach leads to the conclusion that besides asphaltene precipitation, the aggregate size distribution in relation to the size of the emulsion droplets is a critical factor in stabilizing the emulsions. Results presented in thi...

show abstract

Section: Resultssupporting

confidence: 57%

Section: Introductionmentioning

confidence: 99%

Role of Asphaltene in Stability of Water-in-Oil Model Emulsions: The Effects of Oil Composition and Size of the Aggregates and Droplets

Velayati

Nouri

2021

Energy Fuels

View full text Add to dashboard Cite

show abstract

“…The names refer to the 13 samples selected for this study. 2016; Kananpanah et al, 2017;Mohammadi et al, 2017;Afra et al, 2018;Hemmati-Sarapardeh et al, 2018;Hemmati-Sarapardeh et al, 2020). It can furthermore be deduced that the XRD results are precise and repeatable, since the values for the repeated samples are close to each other (Table 2).…”

Section: Xrd and Ftir Resultssupporting

confidence: 55%

Introducing a Novel Approach for Oil‐Oil Correlation based on Asphaltene Structure: X‐ray Diffraction

Sadeghtabaghi

Rabbani

Hemmati‐Sarapardeh

2021

Acta Geologica Sinica (Eng)

View full text Add to dashboard Cite

Oil-oil correlation is a widely-known concept in geochemical studies, defined as finding geochemical relevance between oil samples (Dembicki, 2016). There is a striking principle which indicates that every oil sample can preserve its chemical characteristic throughout the passage of time. This property, referred to as a fingerprint, can be used for distinguishing differences between one oil sample and others, or detecting similarities between oil samples of a genetic family (Christensen and Tomasi, 2007;Speight, 2014;Hashemi-Nasab and Parastar, 2019). One of the most significant applications of oil-oil correlation is determining the number of active source rocks in a given study area. This can be achieved by identifying existing genetically-distinct oil families in the basin (Dembicki, 2016). Oil-oil correlation also plays a vital role in basin modeling and reconstruction of the burial history of basin sediments (Soltani et al., 2019), as well as precise characterization of the petroleum system

show abstract

“…e effect of the rejuvenator on the aging asphalt is influenced by its microstructure [7]. Dissimilar molecular structures may lead to incompatibility between asphalt and rejuvenator and asphaltene agglomeration to form precipitates [8].…”

Section: Introductionmentioning

confidence: 99%

Microscopic Analysis of the Rejuvenation Mechanism and Rejuvenation Effect of Asphalt Binders

Shi

Bao

et al. 2021

Advances in Materials Science and Engineering

View full text Add to dashboard Cite

This study investigates the rejuvenation mechanism of asphalt binders at the microscopic level and compares the rejuvenation effects of rejuvenators. A model of rejuvenated asphalt was established on the basis of molecular simulation by adding different doses of two rejuvenators to the aged asphalt. This model was validated in terms of density and surface free energy. The diffusion ability of the rejuvenator was investigated by using a diffusion model and mean square displacement. The deagglomeration ability of rejuvenators on asphaltene was explored by using a radial distribution function. The microscopic mechanism of asphalt rejuvenation was explained. Results show that small molecule structures are more diffusible than long-chain structures, and aromatic ring structures are more attracted than polar functional groups. The rejuvenating effect of the rejuvenator was evaluated in terms of viscosity and cohesive energy density. Results show that the long-chain structure reduces the viscosity value more than the small molecule structure. The aromatic ring structure in the aged asphalt helps to restore the compatibility between the fractions. This study serves as a guide for the selection and development of future rejuvenators.

show abstract

Effect of asphaltene structure on its aggregation behavior in toluene-normal alkane mixtures

Cited by 37 publications

References 55 publications

Role of Asphaltene in Stability of Water-in-Oil Model Emulsions: The Effects of Oil Composition and Size of the Aggregates and Droplets

Role of Asphaltene in Stability of Water-in-Oil Model Emulsions: The Effects of Oil Composition and Size of the Aggregates and Droplets

Introducing a Novel Approach for Oil‐Oil Correlation based on Asphaltene Structure: X‐ray Diffraction

Microscopic Analysis of the Rejuvenation Mechanism and Rejuvenation Effect of Asphalt Binders

Contact Info

Product

Resources

About