Characterization of acidic compounds in biodegraded oils

Fafet, A.; Kergall, François; Silva, Martine Da; Béhar, F.

doi:10.1016/j.orggeochem.2008.03.008

Cited by 36 publications

(33 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Further work by Dieker et al 26 and Aman et al [6][7][8] evaluated the impact of crude oil and various carboxylic acids on cyclopentane hydrate cohesive force. These studies concluded that crude oils tended to decrease hydrate cohesive force, 26 and this decrease was suggested to be linked to the amount or kind of naphthenic acid [27][28][29][30][31] present in the oil phase, with a particular focus on polyfunctional carboxylic acids of broad carbon number and hydrogen deficiency range. [32][33][34][35][36][37] Both studies relied on the underlying assumption that interparticle interaction was dominated by capillary cohesion; that is, surfactants weaken the liquid bridge between the hydrate particles and ultimately decrease the cohesive force.…”

Section: Introductionmentioning

confidence: 99%

Interfacial mechanisms governing cyclopentane clathrate hydrate adhesion/cohesion

Aman

Brown

Sloan

et al. 2011

Phys. Chem. Chem. Phys.

225

324

View full text Add to dashboard Cite

The present work uses a micromechanical force apparatus to directly measure cyclopentane clathrate hydrate cohesive force and hydrate-steel adhesive force, as a function of contact time, contact force and temperature. We present a hydrate interparticle force model, which includes capillary and sintering contributions and is based on fundamental interparticle force theories. In this process, we estimate the cyclopentane hydrate tensile strength to be approximately 0.91 MPa. This hydrate interparticle force model also predicts the effect of temperature on hydrate particle cohesion force. Finally, we present the first direct measurements of hydrate cohesive force in the gas phase to be 9.1 ± 2.1 mN/m at approximately 3 °C (as opposed to 4.3 ± 0.4 mN/m in liquid cyclopentane).

show abstract

Section: Introductionmentioning

confidence: 99%

Interfacial mechanisms governing cyclopentane clathrate hydrate adhesion/cohesion

Aman

Brown

Sloan

et al. 2011

Phys. Chem. Chem. Phys.

225

324

View full text Add to dashboard Cite

show abstract

“…Aspenes et al 34 extended these MMF measurements to water-wetted steel, concluding the presence of a capillary bridge increased hydrate adhesive force by a factor of 50Â. When the bulk cyclopentane phase contained 0.6 wt% of naphthenic acid, [35][36][37] Aspenes et al 34 measured a 50% decrease in this wetted adhesive force. These experiments suggest that the surface wetting condition may represent a critical risk to hydrate particle deposition.…”

Section: Introductionmentioning

confidence: 99%

Adhesion force interactions between cyclopentane hydrate and physically and chemically modified surfaces

Aman

Sloan

Sum

et al. 2014

Phys. Chem. Chem. Phys.

View full text Add to dashboard Cite

Interfacial interactions between liquid-solid and solid-solid phases/surfaces are of fundamental importance to the formation of hydrate deposits in oil and gas pipelines. This work establishes the effect of five categories of physical and chemical modification to steel on clathrate hydrate adhesive force: oleamide, graphite, citric acid ester, nonanedithiol, and Rain-X anti-wetting agent. Hydrate adhesive forces were measured using a micromechanical force apparatus, under both dry and water-wet surface conditions. The results show that the graphite coating reduced hydrate-steel adhesion force by 79%, due to an increase in the water wetting angle from 42 ± 8° to 154 ± 7°. Two chemical surface coatings (nonanedithiol and the citric acid ester) induced rapid hydrate growth in the hydrate particles; nonanedithiol increased hydrate adhesive force by 49% from the baseline, while the citric acid ester coating reduced hydrate adhesion force by 98%. This result suggests that crystal growth may enable a strong adhesive pathway between hydrate and other crystalline structures, however this effect may be negated in cases where water-hydrocarbon interfacial tension is minimised. When a liquid water droplet was placed on the modified steel surfaces, the graphite and citric acid ester became less effective at reducing adhesive force. In pipelines containing a free water phase wetting the steel surface, chemical or physical surface modifications alone may be insufficient to eliminate hydrate deposition risk. In further tests, the citric acid ester reduced hydrate cohesive forces by 50%, suggesting mild activity as a hybrid anti-agglomerant suppressing both hydrate deposition and particle agglomeration. These results demonstrate a new capability to develop polyfunctional surfactants, which simultaneously limit the capability for hydrate particles to aggregate and deposit on the pipeline wall.

show abstract

“…This approach allows for a quantification of the extent of depletion of individual hydrocarbons within series of related oils. tion [35][36][37][38][39][40][41]. However, during the same processes acids can also be removed, utilised as substrates for growth by the bacteria [35,38].…”

Section: Biodegradationmentioning

confidence: 99%

“…Here, alkaline base solutions are used to remove the acids based on partition principles [39,48,53,68,98,99]. Another common direct method is solid-liquid extraction.…”

Section: Acid Extractionmentioning

confidence: 99%

Normal phase high performance liquid chromatography for fractionation of organic acid mixtures extracted from crude oils

Borgund

Erstad

Barth

2007

Journal of Chromatography A

View full text Add to dashboard Cite

Crude oil contains such an extensive range of compounds that a complete analysis is impossible. Fractionation by chemical properties is often used to simplify analytical handling. This work presents a high performance liquid chromatography (HPLC) method using normal phase chromatography on a cyano-bonded phase column to separate acid extracts from crude oils into four fractions; non-polar compounds, saturated carboxylic acids, phenols and polyfunctional acids. The method has been developed both in analytical scale for characterisation of acid extracts, and in preparative scale to provide sufficient sample amounts for further analysis by complementary methods.

show abstract

Characterization of acidic compounds in biodegraded oils

Cited by 36 publications

References 17 publications

Interfacial mechanisms governing cyclopentane clathrate hydrate adhesion/cohesion

Interfacial mechanisms governing cyclopentane clathrate hydrate adhesion/cohesion

Adhesion force interactions between cyclopentane hydrate and physically and chemically modified surfaces

Normal phase high performance liquid chromatography for fractionation of organic acid mixtures extracted from crude oils

Contact Info

Product

Resources

About