Efficient demulsification of oil-in-water emulsions using a zeolitic imidazolate framework: Adsorptive removal of oil droplets from water

A switchable superlyophobic ZIF-8 membrane can selectively remove oil droplets in oil-in-water emulsions via superoleophobicity and water droplets in water-in-oil emulsions via superhydrophobicity.

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Communication: On the Stability and Necessary Electrophoretic Mobility of Bare Oil Nanodroplets in Water

10.26434/chemrxiv.12451796.v1 ◽

2020 ◽

Author(s):

Saranya Pullanchery ◽

Sergey Kulik ◽

halil okur ◽

Hilton. B. de Aguiar ◽

Sylvie Roke

Keyword(s):

Electrophoretic Mobility ◽

Dlvo Theory ◽

Air Bubbles ◽

Oil Droplets ◽

Cleaning Procedure ◽

Charged Droplets ◽

Oil In Water ◽

The Creation ◽

The Stability ◽

The 19Th Century

Hydrophobic oil droplets, particles and air bubbles can be dispersed in water as kinetically stabilized dispersions. It has been established since the 19th century that such objects harbor a negative electrostatic potential roughly twice larger than the thermal energy. The source of this charge continues to be one of the core observations in relation to hydrophobicity and its molecular explanation is still debated. What is clear though, is that the stabilizing interaction in these systems is understood in terms of electrostatic repulsion via DLVO theory. Recent work [Carpenter et al., PNAS 116 (2019) 9214] has added another element into the discussion, reporting the creation of bare near-zero charged droplets of oil in water that are stable for several days. Key to the creation of the droplets is a rigorous glassware cleaning procedure. Here, we investigate these conclusions and show that the cleaning procedure of glassware has no influence on the electrophoretic mobility of the droplets, that oil droplets with near-zero charge are unstable, and provide an alternative possible explanation for the observations involving glass surface chemistry.

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Adsorptive removal of toluene and carbon tetrachloride from gas phase using Zeolitic Imidazolate Framework-8: Effects of synthesis method, particle size, and pretreatment of the adsorbent

Microporous and Mesoporous Materials ◽

10.1016/j.micromeso.2018.04.013 ◽

2018 ◽

Vol 268 ◽

pp. 58-68 ◽

Cited By ~ 24

Author(s):

Saeed Jafari ◽

Farshid Ghorbani-Shahna ◽

Abdulrahman Bahrami ◽

Hossein Kazemian

Keyword(s):

Particle Size ◽

Carbon Tetrachloride ◽

Gas Phase ◽

Synthesis Method ◽

Zeolitic Imidazolate Framework ◽

Adsorptive Removal

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SHORELINE CLEANSING BY INTERACTIONS BETWEEN OIL AND FINE MINERAL PARTICLES

International Oil Spill Conference Proceedings ◽

10.7901/2169-3358-1995-1-219 ◽

1995 ◽

Vol 1995 (1) ◽

pp. 219-227 ◽

Cited By ~ 26

Author(s):

James R. Bragg ◽

Edward H. Owens

Keyword(s):

Potential Role ◽

Sea Water ◽

Field Studies ◽

Low Energy ◽

Oil Removal ◽

Oil Droplets ◽

Mineral Particles ◽

Treatment Techniques ◽

Oil In Water ◽

Flocculation Process

ABSTRACT Interactions of fine mineral particles with oil stranded on shorelines following spills has been shown to be an important natural cleansing process, capable of accelerating oil removal in most environments, and particularly in low energy environments where wave action and abrasion are negligible. This process involves formation of solids-stabilized oil-in-water emulsions by flocculation of micron-sized mineral fines with oil droplets in the presence of water containing ions (such as sea water). Once flocculated, the oil droplets do not coalesce, and the oil no longer adheres strongly to shoreline sediments, facilitating its removal and dispersion by waves and tidal currents. The importance of the flocculation process to the rate of oil removal from sediments, the conditions needed for the process to occur, and the properties of the resulting floe have been studied in detail for the Exxon Valdez spill. Its potential role in shoreline cleansing also has been studied for other recent spills: Metula (1974, Chile), Arrow (1970, Nova Scotia), BIOS test spill (1981, Cape Hatt, Northwest Territories), Nosac Forest (1993, Tacoma, Washington), and Fred Bouchard (1993, Tampa, Florida). This paper summarizes the various laboratory and field studies and discusses the findings within the contexts of natural shoreline cleansing, and the use of certain treatment techniques.

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