Characterization of Water/Supercritical CO2 Microemulsion by UV-visible Spectroscopy and Dynamic Light Scattering

The Journal of Supercritical Fluids

Ardyani

Sagisaka³

et al. 2015

Self Cite

The article addresses an interesting issue in the development of hybrid surfactants for waterin-CO2 (w/c) microemulsion stabilisation: the role of surfactant headgroup on the surfactant performance. The synthetic procedure, aqueous properties, and phase behaviour of a new hybrid sulfoglutarate surfactant are described. The compound resembles sulfosuccinate surfactants, commonly used to stabilize w/c phases, but with an extra methylene group incorporated into the hydrophilic headgroup. For comparison purposes, the related hydrocarbon (AOT14 and AOT14GLU) and fluorocarbon (di-CF2 and di-CF2GLU) surfactants are used to form w/c microemulsions. In general, the aqueous properties and w/c phase stability of both sulfoglutarates and sulfosuccinates are found to be similar, which shows the secondary role of the hydrophilic headgroup. Interestingly, the newly synthesised hybrid CF2/AOT14GLU (sodium (4H,4H,5H,5H,5H-pentafluoropentyl-2,2-dimethyl-1-propyl)-2-sulfoglutarate) proved to be more efficient than the normal sulfosuccinate, hybrid CF2/AOT14 (Ptrans = 383 bar, γcmc = 26.8 mN m -1 ) in terms of the aqueous behaviour and w/c phase stability.Switching to the sulfoglutarate compound, hybrid CF2/AOT14GLU (Ptrans = 232 bar, γcmc = 20.6 mN m -1 ) more effectively decreases the air-water surface tension by about ~ 5 mN m -1 as compared to the sulfosuccinate. High-pressure phase behaviour studies show significant improvements in stabilising w/c microemulsions at much lower cloud pressures. The results indicate distinct effects of the headgroup structure on the phase behaviour and physicochemical properties, particularly for this hybrid surfactant.

Section: High-pressure Phase Behaviour and Uv-visible Absorption Measmentioning

confidence: 99%

Economical and Efficient Hybrid Surfactant with Low Fluorine Content for the Stabilisation of Water-in-CO2 Microemulsions

The Journal of Supercritical Fluids

Ardyani

Sagisaka³

et al. 2015

Self Cite

“…The amount of water dispersed in CO 2 was expressed as the water-to-surfactant molar ratio (w). CO 2 densities were calculated using the Span-Wagner EOS [19,20].…”

Section: High-pressure Phase Behaviour Of Metallosurfactants and Supementioning

confidence: 99%

“…1 -2). Thus, the relative viscosity of the metallosurfactant-CO 2 systems (η mic/ η CO 2 ) is obtained as follows: (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28) https://ejournal.upsi.edu.my/journal/EDSC enhancement. The work presented here, in agreement with that study, shows that Co 2+ and Ni 2+ salts of di-HCF4 resulted in an increase in relative viscosity of up to 90%.…”

Section: High-pressure Viscosity Of Metallosurfactant-co 2 Systemsmentioning

confidence: 99%

“…4 No. 2 (2017) ISSN 2289-7070 / eISSN 2462-2451 (16)(17)(18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28) https://ejournal.upsi.edu.my/journal/EDSC noted before for w/c microemulsions, is indicative of the swelling of micelles with added water [25]. The phase behaviour is consistent with the following scenario: when micelles become swollen with water, attractive micelle-micelle interactions are strengthened, thus higher pressures are required to overcome tail/tail interactions and prevent phase separation.…”

Section: High-pressure Viscosity Of Metallosurfactant-co 2 Systemsmentioning

confidence: 99%

See 1 more Smart Citation

Synthesis and Characterisation of Metallosurfactants as Carbon Dioxide Viscosity Modifier

Abdosalam

2017

EJSMT

This paper focuses on a systematic approach to enhance the viscosity of supercritical CO 2 (scCO 2) for enhanced recovery applications. Recent successful results have shown for the first time that fluorinated surfactants can be used as viscosity modifiers for CO 2. Although some fluorinated surfactants have been synthesised, up to now no systematic studies have been carried out toward scCO 2 viscosity enhancement and impeded commercial developments of viscosity modifier. Here, metallosurfactant structure design was focused on anionic surfactant analogues of Aerosol-OT (sodium bis (2-ethyexyl) sulfosuccinate). The metallosurfactant were systematically synthesised with modification centred on fluorinated content in surfactant chain with introduction of nickel (Ni 2+) and manganese (Co 2+) counter ions. The metallosurfactant have been investigated by a range of techniques including Nuclear Magnetic Resonance (NMR) Spectroscopy, UV-Visible Spectroscopy and High-Pressure Viscometer. The result shows that fluorination is a crucial factor influencing Aerosol-OT surfactant analogue compatibility with scCO 2. The presence of fluorine in the metallosurfactant chemical structure gives rise to relative scCO 2 viscosity. The results obtained are beneficial for expanding CO 2 in enhanced oil recovery applications and realising its potential using the most efficient metallosurfactant as CO 2 viscosity modifier.

“…(MO is insoluble in sc-CO2 and soluble in water.) The existence of reverse micelles in sc-CO2 is indicated by the red dyed single-phase mixtures because the MO dissolves inside surfactant-stabilized water pools of the CO2 continuous phase [44]. The UV-visible absorption spectra of MO in the water/surfactant/CO2 systems are shown in Figure 3.…”

Section: Uv-visible Spectroscopy Measurement Of W/c Microemulsionsmentioning

confidence: 99%

Effect of surfactant headgroup on low-fluorine-content CO2-philic hybrid surfactants

The Journal of Supercritical Fluids

Ardyani

Bakar

et al. 2016

Self Cite

General rightsThis document is made available in accordance with publisher policies. Please cite only the published version using the reference above. Full terms of use are available: http://www.bristol.ac.uk/pure/about/ebr-terms AbstractThe article addresses the role of surfactant headgroup structure on hybrid surfactant performance for water-in-CO2 (w/c) microemulsion stabilisation. The synthetic procedure, aqueous properties, and phase behaviour of a new hybrid sulfoglutarate surfactant are described. The sulfoglutarate version has an extra methylene group incorporated into the hydrophilic headgroup. The related hydrocarbon (AOT14 and AOT14GLU) and fluorocarbon (di-CF2 and di-CF2GLU) surfactants were used to form w/c microemulsions. For these two groups, the aqueous properties and w/c phase stability of both sulfoglutarates and sulfosuccinates were found to be similar. The newly synthesized hybrid CF2/AOT14GLU (sodium (4H,4H,5H,5H,5H-pentafluoropentyl-2,2-dimethyl-1-propyl)-2-sulfoglutarate)proved to be more efficient than the normal sulfosuccinate, hybrid CF2/AOT14 in terms of the aqueous behaviour and w/c phase stability. Hybrid CF2/AOT14GLU more effectively decreased the air-water surface tension by ~ 2 mN m -1 and lowering the cloud pressures on CO2 by ~150 bar.