Development of Janus Cellulose Acetate Fiber (CA) Membranes for Highly Efficient Oil–Water Separation

A new type of Janus cellulose acetate (CA) fiber membrane was used to separate oil–water emulsions, which was prepared with plasma gas phase grafting by polymerizing octamethylcyclotetrasiloxane (D4) onto a CA fiber membrane prepared by centrifugal spinning. The Janus–CA fiber membrane was described in terms of chemical structure using Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) analysis, energy dispersive X-ray spectroscopy (EDX) analysis and morphology by field emission scanning electron microscopy (FESEM). In this contribution, we examine the influence of spinning solution concentration, spinning speed and nozzle aperture on the centrifugal spinning process and the fiber morphology. Superhydrophobic/hydrophilic Janus–CA fiber membrane was used to separate water and 1,2-dibromoethane mixture and Toluene-in-water emulsion. Unidirectional water transfer Janus–CA fiber membrane was used to separate n-hexane and water mixture. The separation for the first-time interception rate was about 98.81%, 98.76% and 98.73%, respectively. Experimental results revealed that the Janus cellulose acetate (CA) fiber membrane gave a permeate flux of about 43.32, 331.72 and 275.27 L/(m2·h), respectively. The novel Janus–CA fiber membrane can potentially be used for sustainable W/O emulsion separation. We believe that this is a facile strategy for construction of filtration materials for practical oil–water separation.

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Application of a triblock copolymer additive modified polyvinylidene fluoride membrane for effective oil/water separation

Royal Society Open Science ◽

10.1098/rsos.171979 ◽

2018 ◽

Vol 5 (5) ◽

pp. 171979 ◽

Cited By ~ 4

Author(s):

S. S. Shen ◽

K. P. Liu ◽

J. J. Yang ◽

Y. Li ◽

R. B. Bai ◽

...

Keyword(s):

Polyvinylidene Fluoride ◽

Triblock Copolymer ◽

Oily Wastewater ◽

The Novel ◽

Permeate Flux ◽

Cleaning Efficiency ◽

Water Separation ◽

Water Emulsion ◽

Oil Water Separation ◽

Oil Water

A hollow fibre membrane was fabricated by blending polyvinylidene fluoride (PVDF) with a triblock copolymer additive polymer that has both hydrophilic and oleophobic surface properties. The novel membrane was characterized and examined for oil/water separation under various system conditions, including different cross-flow rate, feed temperature, trans-membrane pressure, and its rejection and cleaning efficiency, etc. By applying the membrane into the filtration of synthesized oil/water emulsion, the membrane constantly achieved an oil rejection rate of above 99%, with a relatively constant permeate flux varied in the range of 68.9–59.0 l m −2 h −1 . More importantly, the fouling of the used membrane can be easily removed by simple water flushing. The membrane also demonstrated a wide adaptability for different types of real oily wastewater, even at very high feed oil concentration (approx. 115 000 mg l −1 in terms of chemical oxygen demand (COM)). Hence, the novel triblock copolymer additive-modified PVDF membrane can have a great prospect in the continuing effort to expand the engineering application of polymeric membranes for oily wastewater treatment.

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Fabrication of silica/PVA-co-PE nanofiber membrane for oil/water separation

Fashion and Textiles ◽

10.1186/s40691-021-00252-x ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yuanli Chen ◽

Hui Fan ◽

Xinlin Zha ◽

Wenwen Wang ◽

Yi Wu ◽

...

Keyword(s):

High Efficiency ◽

Silicone Oil ◽

Hydroxyl Groups ◽

Water Mixture ◽

Silica Nanospheres ◽

Nanofiber Membrane ◽

Water Separation ◽

Oil Water Separation ◽

Silica Nanostructures ◽

Oil Water

AbstractHigh efficiency and anti-pollution oil/water separation membrane has been widely explored and researched. There are a large number of hydroxyl groups on the surface of silica, which has good wettability and can be used for oil-water separation membranes. Hydrophilic silica nanostructures with different morphologies were synthesized by changing templates and contents of trimethylbenzene (TMB). Here, silica nanospheres with radical pores, hollow silica nanospheres and worm-like silica nanotubes were separately sprayed on the PVA-co-PE nanofiber membrane (PM). The abundance of hydroxyl groups and porous structures on PM surfaces enabled the absorption of silica nanospheres through hydrogen bonds. Compared with different silica nanostructures, it was found that the silica/PM exhibited excellent super-hydrophilicity in air and underwater “oil-hating” properties. The PM was mass-produced in our lab through melt-extrusion-phase-separation technique. Therefore, the obtained membranes not only have excellent underwater superoleophobicity but also have a low-cost production. The prepared silica/PM composites were used to separate n-hexane/water, silicone oil/water and peanut oil water mixtures via filtration. As a result, they all exhibited efficient separation of oil/water mixture through gravity-driven filtration.

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Gravity-Driven Separation of Oil/Water Mixture by Porous Ceramic Membranes with Desired Surface Wettability

Materials ◽

10.3390/ma14020457 ◽

2021 ◽

Vol 14 (2) ◽

pp. 457

Author(s):

Chunlei Ren ◽

Wufeng Chen ◽

Chusheng Chen ◽

Louis Winnubst ◽

Lifeng Yan

Keyword(s):

Porous Ceramic ◽

Ceramic Membranes ◽

Separation Performance ◽

Water Mixture ◽

Alumina Membrane ◽

Water Separation ◽

Alumina Membranes ◽

Oil Water Separation ◽

Gravity Driven ◽

Oil Water

Porous Al2O3 membranes were prepared through a phase-inversion tape casting/sintering method. The alumina membranes were embedded with finger-like pores perpendicular to the membrane surface. Bare alumina membranes are naturally hydrophilic and underwater oleophobic, while fluoroalkylsilane (FAS)-grafted membranes are hydrophobic and oleophilic. The coupling of FAS molecules on alumina surfaces was confirmed by Thermogravimetric Analysis and X-ray Photoelectron Spectroscopy measurements. The hydrophobic membranes exhibited desired thermal stability and were super durable when exposed to air. Both membranes can be used for gravity-driven oil/water separation, which is highly cost-effective. The as-calculated separation efficiency (R) was above 99% for the FAS-grafted alumina membrane. Due to the excellent oil/water separation performance and good chemical stability, the porous ceramic membranes display potential for practical applications.

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Development of Red Clay Ultrafiltration Membranes for Oil-Water Separation

Crystals ◽

10.3390/cryst11030248 ◽

2021 ◽

Vol 11 (3) ◽

pp. 248

Author(s):

Saad A. Aljlil

Keyword(s):

Ceramic Membrane ◽

Applied Pressure ◽

Operating Pressure ◽

Permeate Flux ◽

Carbon Membrane ◽

Red Clay ◽

Water Separation ◽

Water Emulsion ◽

Cross Flow Filtration ◽

Oil Water

In this study, a red clay/nano-activated carbon membrane was investigated for the removal of oil from industrial wastewater. The sintering temperature was minimized using CaF2 powder as a binder. The fabricated membrane was characterized by its mechanical properties, average pore size, and hydrophilicity. A contact angle of 67.3° and membrane spore size of 95.46 nm were obtained. The prepared membrane was tested by a cross-flow filtration process using an oil-water emulsion, and showed a promising permeate flux and oil rejection results. During the separation of oil from water, the flux increased from 191.38 to 284.99 L/m2 on increasing the applied pressure from 3 to 6 bar. In addition, high water permeability was obtained for the fabricated membrane at low operating pressure. However, the membrane flux decreased from 490.28 to 367.32 L/m2·h due to oil deposition on the membrane surface; regardless, the maximum oil rejection was 99.96% at an oil concentration of 80 NTU and a pressure of 5 bar. The fabricated membrane was negatively charged, as were the oil droplets, thereby facilitating membrane purification through backwashing. The obtained ceramic membrane functioned well as a hydrophilic membrane and showed potential for use in oil wastewater treatment.

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A Micro/Nano Engineering Laboratory Module on Superoleophobic Membranes for Oil-Water Separation

MRS Advances ◽

10.1557/adv.2017.255 ◽

2017 ◽

Vol 2 (31-32) ◽

pp. 1699-1706

Author(s):

Hussain Al-Qahtani ◽

Michael S. H. Boutilier ◽

Rahul Ramakrishnan ◽

Rohit Karnik

Keyword(s):

Petroleum Industry ◽

Spray Coating ◽

Titania Nanoparticles ◽

Water Mixture ◽

Massachusetts Institute Of Technology ◽

Water Separation ◽

Societal Needs ◽

Oil Water Separation ◽

Oil Water ◽

Institute Of Technology

ABSTRACTThis article presents a laboratory module developed for undergraduate micro/nano engineering laboratory courses in the mechanical engineering departments at the Massachusetts Institute of Technology and King Fahd University of Petroleum and Minerals. In this laboratory, students fabricate superoleophobic membranes by spray-coating of titania nanoparticles on steel meshes, characterize the surfaces and ability of the membrane to retain oil, and then use these membranes to separate an oil-water mixture. The laboratory module covers nanomaterials, nanomanufacturing, materials characterization, and understanding of the concepts of surface tension and hydrostatics, with oil-water separation as an application. The laboratory experiments are easy to set up based on commercially available tools and materials, which will facilitate implementation of this module in other educational institutions. The significance of oil-water separation in the petroleum industry and integration of concepts from fluid mechanics in the laboratory module will help to illustrate the relevance of nanotechnology to mechanical and materials engineering and its potential to address some of the future societal needs.

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A facile surface modification of a PVDF membrane via CaCO3 mineralization for efficient oil/water emulsion separation

New Journal of Chemistry ◽

10.1039/d0nj03329d ◽

2020 ◽

Vol 44 (48) ◽

pp. 20999-21006

Author(s):

Junda Wu ◽

Atian Xie ◽

Jin Yang ◽

Jiangdong Dai ◽

Chunxiang Li ◽

...

Keyword(s):

Self Assembly ◽

Layer By Layer ◽

Assembly Process ◽

Water Separation ◽

Water Emulsion ◽

Pvdf Membrane ◽

Inorganic Particles ◽

Emulsion Separation ◽

Oil Water Separation ◽

Oil Water

A facile modification of a PVDF membrane using CaCO3 inorganic particles via a layer-by-layer self-assembly process for efficient oil/water separation.

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Surface Engineering of Ceramic Nanomaterials for Separation of Oil/Water Mixtures

Frontiers in Chemistry ◽

10.3389/fchem.2020.00578 ◽

2020 ◽

Vol 8 ◽

Author(s):

Usama Zulfiqar ◽

Andrew G. Thomas ◽

Allan Matthews ◽

David J. Lewis

Keyword(s):

Surface Engineering ◽

Oil Spills ◽

Chemical Interaction ◽

Low Cost ◽

Water Mixture ◽

Water Separation ◽

Manufacturing Operations ◽

Industrial Oil ◽

Oil Water Separation ◽

Oil Water

Oil/water mixtures are a potentially major source of environmental pollution if efficient separation technology is not employed during processing. A large volume of oil/water mixtures is produced via many manufacturing operations in food, petrochemical, mining, and metal industries and can be exposed to water sources on a regular basis. To date, several techniques are used in practice to deal with industrial oil/water mixtures and oil spills such as in situ burning of oil, bioremediation, and solidifiers, which change the physical shape of oil as a result of chemical interaction. Physical separation of oil/water mixtures is in industrial practice; however, the existing technologies to do so often require either dissipation of large amounts of energy (such as in cyclones and hydrocyclones) or large residence times or inventories of fluids (such as in decanters). Recently, materials with selective wettability have gained attention for application in separation of oil/water mixtures and surfactant stabilized emulsions. For example, a superhydrophobic material is selectively wettable toward oil while having a poor affinity for the aqueous phase; therefore, a superhydrophobic porous material can easily adsorb the oil while completely rejecting the water from an oil/water mixture, thus physically separating the two components. The ease of separation, low cost, and low-energy requirements are some of the other advantages offered by these materials over existing practices of oil/water separation. The present review aims to focus on the surface engineering aspects to achieve selectively wettability in materials and its their relationship with the separation of oil/water mixtures with particular focus on emulsions, on factors contributing to their stability, and on how wettability can be helpful in their separation. Finally, the challenges in application of superwettable materials will be highlighted, and potential solutions to improve the application of these materials will be put forward.

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Experimental Research on the Effect of Heating Temperature, Demulsifier Dose and Water Cut on the Oil-Water Separation in Three-Phase Separator

Volume 7: Operations, Applications, and Components ◽

10.1115/pvp2018-84285 ◽

2018 ◽

Author(s):

Ang Li ◽

Jianfeng Bai ◽

Yun Shen ◽

Hang Jin ◽

Wei Wang ◽

...

Keyword(s):

Heating Temperature ◽

High Water ◽

Water Mixture ◽

Water Separation ◽

Three Phase ◽

Wide Range ◽

Oil Water Separation ◽

Oil Water ◽

Water Cut ◽

Phase Separator

The three-phase separator has a wide range of applications in oil production industry. For the purpose of studying the effect of heating temperature, demulsifiers and water content on the separation of oil-water mixture in the three-phase separator, eight kinds of oil samples were taken from different oil transfer stations in Changqing Oilfield and the mixtures were prepared by stirring method. To simulate the two-stage dehydration process, the first stage dehydration experiments without any heating were performed on mixtures at the dose of 100ppm demulsifer at 20°C, and the water cut of these mixtures is the same as that of the gathering pipeline in each oil transfer station. The water cut of the upper crude oil was measured after 40 minutes, and the values of them ranged from 0.5 vol% to 65.2 vol%. No visual stratification was observed for the sample most difficult to separate, so it was selected to conduct the second stage dewatering process. Three bottles of the same mixture were prepared and heated to 30°C, 40°C and 50°C, respectively. The results showed that all of them stratified in 10 minutes, and the water-cut values of the upper oil layer were 1.4 vol%, 0.5 vol% and 0.3 vol%, respectively, compared to 65.2 vol% at 20°C. When the concentration of demulsifier was changed to 200ppm and 300ppm, the results exhibited almost no differences. So it is deduced that the further improvement of heating temperature and demulsifier dose have limited enhancement on oil-water separation. At Last, 35 vol%, 50 vol%, 70 vol% and 85 vol% water cut mixtures of the special oil sample were made to experiment as previously. In consequence, the 35 vol% water-cut emulsions presented a relatively slow rate of oil-water stratification at low heating temperature, and the oil content of the lower separated water was improved by the addition of demulsifier dosage above 100ppm when the water cut was 90 vol%. It is indicated that high heating temperature is necessarry for low water-cut mixtures oil-water separation and can be appropriately reduced to save energy consumption as the water cut continues to rise. The demulsifier dosage is also neccessary be controlled in high water cut period. These experimental data provide the basis for the further optimization operation of the three-phase separator.

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Preparation of compressible polymer monoliths that contain mesopores capable of rapid oil–water separation

Polymer Chemistry ◽

10.1039/c9py00967a ◽

2019 ◽

Vol 10 (37) ◽

pp. 5142-5150 ◽

Cited By ~ 5

Author(s):

Ji Ae Chae ◽

Yuree Oh ◽

Hea Ji Kim ◽

Go Bong Choi ◽

Kyoung Min Lee ◽

...

Keyword(s):

Water Mixture ◽

Rapid Separation ◽

Water Separation ◽

Bottom Up ◽

Polymer Monoliths ◽

Polymer Monolith ◽

Oil Water Separation ◽

Oil Water

A bottom-up design enables the preparation of a mesoporous, compressible, polymer monolith that shows rapid separation of oil–water mixture.

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Micro/Nanoscale Structured Superhydrophilic and Underwater Superoleophobic Hybrid-Coated Mesh for High-Efficiency Oil/Water Separation

Polymers ◽

10.3390/polym12061378 ◽

2020 ◽

Vol 12 (6) ◽

pp. 1378

Author(s):

Teng Yuan ◽

Jian Yin ◽

Yingling Liu ◽

Weiping Tu ◽

Zhuohong Yang

Keyword(s):

Contact Angle ◽

Surface Topography ◽

Cross Linking ◽

Permeate Flux ◽

Stainless Steel Mesh ◽

Water Separation ◽

Nano Sio2 ◽

Binary Structure ◽

Oil Water Separation ◽

Oil Water

A novel micro/nanoscale rough structured superhydrophilic hybrid-coated mesh that shows underwater superoleophobic behavior is fabricated by spray casting or dipping nanoparticle–polymer suspensions on stainless steel mesh substrates. Water droplets can spread over the mesh completely; meanwhile, oil droplets can roll off the mesh at low tilt angles without any penetration. Besides overcoming the oil-fouling problem of many superhydrophilic coatings, this superhydrophilic and underwater superoleophobic mesh can be used to separate oil and water. The simple method used here to prepare the organic–inorganic hybrid coatings successfully produced controllable micro-nano binary roughness and also achieved a rough topography of micro-nano binary structure by controlling the content of inorganic particles. The mechanism of oil–water separation by the superhydrophilic and superoleophobic membrane is rationalized by considering capillary mechanics. Tetraethyl orathosilicate (TEOS) as a base was used to prepare the nano-SiO2 solution as a nano-dopant through a sol-gel process, while polyvinyl alcohol (PVA) was used as the film binder and glutaraldehyde as the cross-linking agent; the mixture was dip-coated on the surface of 300-mesh stainless steel mesh to form superhydrophilic and underwater superoleophobic film. Properties of nano-SiO2 represented by infrared spectroscopy and surface topography of the film observed under scanning electron microscope (SEM) indicated that the film surface had a coarse micro–nano binary structure; the effect of nano-SiO2 doping amount on the film’s surface topography and the effect of such surface topography on hydrophilicity of the film were studied; contact angle of water on such surface was tested as 0° by the surface contact angle tester and spread quickly; the underwater contact angle to oil was 158°, showing superhydrophilic and underwater superoleophobic properties. The effect of the dosing amount of cross-linking agent to the waterproof swelling property and the permeate flux of the film were studied; the oil–water separation effect of the film to oil–water suspension and oil–water emulsion was studied too, and in both cases the separation efficiency reached 99%, which finally reduced the oil content to be lower than 50 mg/L. The effect of filtration times to permeate flux was studied, and it was found that the more hydrophilic the film was, the stronger the stain resistance would be, and the permeate flux would gradually decrease along with the increase of filtration times.

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