Oil-water Separation Efficiency Research Articles

A novel bio-aerogel based on agroforestry waste chestnut shell for enhanced oil-water separation performance

Bio-based aerogels have attracted much attention due to their biodegradability and excellent oil-water separation properties. However, the preparation of inexpensive green aerogels with high separation efficiency is still a great challenge. In this paper, low-density, high-adsorption capacity and superhydrophobic chestnut shell-based bio-aerogels were prepared by chemical cross-linking and chemical vapor deposition using agricultural and forestry waste chestnut shells as the precursor of aerogels to achieve high efficiency of oil-water separation and to achieve the goal of “treating waste with waste”. The covalent cross-linking of chestnut shell cellulose and cross-linking agent to form silicone-containing functional groups improved the pore structure, hydrophobicity and mechanical properties of chestnut shell cellulose, and under the action of capillary force, the oil was retained in the pores of the bio-aerogels, which achieved the selective adsorption of oil and organic solvents in the oil-water mixture, with a separation efficiency of more than 98%. After 10 cycles, the bio-aerogel still has good reusability. This eco-friendly and low-cost aerogel provides a practical method for resource conversion and recycling, as well as a green and innovative way for the treatment of oily wastewater.

Fabrication of Micro/Nanostructured Copper Fibers by Vibration Cutting for Felt-Based Freshwater Purification

Freshwater purification from wasted water and seawater is crucial in addressing the global problem of water scarcity. Porous fiber felt with a micro/nanostructure emerges as an efficient approach for water purification; however, its production usually relies on chemical postprocessing to create micro/nano structures on the fiber surface, which might pollute the environment. This study proposed an ecofriendly method to produce micro/nanostructured copper fiber felt without chemical treatment. First, a new transverse-feeding vibration cutting is proposed to fabricate micro/nanostructured fibers with controllable structure characteristics. Through the sintering of the structured fibers without postprocessing, the fiber felt can be produced in an ecofriendly way and exhibit special wettability and excellent photothermal properties. Felt-based freshwater purification, including oil–water separation and solar-driven seawater desalination, can be realized effectively. Results show an oil–water separation efficiency of > 90% and a high evaporation rate of water of > 1.08 kg m−2 h−1 at 73 mW cm−2 are achieved, demonstrating the application prospect of the produced fiber felt.

Preparation of the sandwiched PS-SiO2-PVAc-SiO2 electrospinning fiber membrane with super-hydrophobic and self-cleaning and its performance in oil-water emulsion separation

Oil-water emulsion separation could improve the efficiency of oil resources and reduce environmental pollution. The efficiency of oil-water separation was directly affected by the surface hydrophobicity of the membrane and its reliability and reusability. Therefore, the construction of a reliable and reusable super-hydrophobic surface was very important. In this research, the EFM with sandwich structure of PS-SiO2-PVAc-SiO2 was easily fabricated by a three times liquid phase induction process and heat treatment. The PS-SiO2-PVAc-SiO2 EFM was first formed by a triple liquid phase induction process, then the EFM was heat-treated, the PVAc, which is a heat-sensitive material, resulting in SiO2 nanoparticles being welded onto PS fibers. The rolling contact angle experiment at an inclination of 8° proved that the PS-SiO2-PVAc-SiO2 EFM has super-hydrophobic properties. Meanwhile, the PS-SiO2-PVAc-SiO2 EFM showed excellent stability and reliability of super-hydrophobic properties after the EFM was washed or taped. In addition, the PS-SiO2-PVAc-SiO2 EFM had self-cleaning function and fine oil-water separation property. The oil-water separation efficiency was over 99.50 % and the flow rate was 68 L/m2h. After 5 times of oil-water separation, the flux and separation efficiency did not decrease significantly, which proved that the PS-SiO2-PVAc-SiO2 EFM could be reusable.

Enhancing durability and oil-water separation efficiency with plasma-treated graphene oxide coated mesh

In recent years, there has been a surge in interest surrounding the fabrication and utilization of superhydrophobic and superhydrophilic surfaces, driven by their exceptional functionalities and properties. Graphene Oxide (GO) has inherent hydrophilicity and underwater superoleophobicity, which has made this material a particularly capable candidate for oil-water separation. Addressing the persistent challenge of efficient oil-water separation in industrial contexts, this study presents the fabrication of a GO-coated stainless steel mesh via a facile dip coating method augmented by an intermediate two-step O2 plasma treatment. The coated meshes were tested with various oil and water mixtures, including neutral, acidic, saline, and hot water, to find separation efficiency and recyclability. Notably, the meshes can achieve excellent separation efficiency of approximately 98.9 % and a superior flux of 11,464 L m−2 h−1 driven by gravity. This is a significant improvement over GO-coated meshes without O2 plasma treatment. Moreover, the plasma-treated meshes exhibit robust long-term durability and chemical stability, maintaining high underwater oil contact angles ≥119° even after extended immersion in diverse pH mediums and salt solutions for 150 days. This work showcases the practical viability of plasma-treated GO-coated meshes for oil-water separation applications and establishes a framework for systematically evaluating their long-term performance in harsh immersion conditions.

Preparation of superhydrophobic polyurethane sponge with photodegradation function and study on its oil-water separation performance

The surface of tetrapod-shaped zinc oxide whiskers (T-ZnOw) was hydrophobized by the sol-gel method, and then loaded onto the surface of polyurethane sponge by dip-curing method to prepare a superhydrophobic polyurethane sponge with photodegradation function. When the mass ratio of superhydrophobic tetrapod-shaped zinc oxide whiskers (ST-ZnOw) and polydimethylsiloxane (PDMS) was 0.5:1, the water contact angle of the sponge was 157.5°. After being soaked in acid and alkali corrosion solution, rubbed with sandpaper and heat treated, the sponge can still maintain excellent hydrophobic properties. The adsorption capacity for different oils and organic solvents is 12 to 35 times of its own mass. After repeated extrusion-oil absorption experiments, it can still maintain its good adsorption capacity and high hydrophobicity, showing excellent reusability. The continuous oil-water separation efficiency of the material for different oils and organic solvents is above 95%, and the separation efficiency for the emulsion prepared with span80 content of 0.1wt% is 99.84%. At the same time, the prepared material can degrade the organic dye methylene blue under ultraviolet light, with a degradation rate of 99.35%, showing excellent potential for degrading organic pollutants.

All-electrochemical-prepared, efficient and robust superhydrophilic/underwater superoleophobic meshes for synchronously achieving oil-water separation and water-soluble pollutant photodegradation

Superhydrophilic/underwater superoleophobic “water-removing” type membranes can overcome the issue of surface themselves easily fouled or even blocked by oils that seriously affects the oil-water separation capacity and limits the recycle use, and thus attract a great deal of research attention. In this work, we employed the electrochemical deposition method to fabricate Cu3(PO4)2 nanosheets (NSs) vertically grown on a copper mesh (COM) to achieve efficient oil-water separation, followed by the deposition of titanium dioxide (TiO2) nanoparticles and graphitic carbon nitride (g-C3N4) nanosheets on the surface of Cu3(PO4)2 nanosheets-wrapped mesh (Cu3(PO4)2@COM), respectively. The composited meshes of TiO2@Cu3(PO4)2@COM and g-C3N4@Cu3(PO4)2@COM not only showed the considerable superhydrophilic/underwater superoleophobic property in the application of oil-water separation, but also simultaneously exhibited the desirable photocatalytic activity for the degradation of water-soluble pollutants as the water passed through the meshes. The oil-water separation efficiency of TiO2@Cu3(PO4)2@COM and g-C3N4@Cu3(PO4)2@COM can reach as high as 97 % and 96 % that both of meshes have the water flux of various water-oil mixtures above 3250 L/m2h, along with their degradation efficiency of 79 % and 90 % for RhB pollutant under full spectrum light irradiation, respectively. In addition, the as-prepared meshes have the robust, sustainable and stable properties through ten-cycles test of oil-water separation and photocatalytic degradation without significant performance decay. Our primary results provide a potential and simple route to construct multifunctional membrane materials for synchronously achieving water purification in oily wastewater.

Robust multifunctional superhydrophobic and photocatalytic composites with all-weather self-healing ability

Superhydrophobic surfaces with rapid self-healing ability are ideal for long-life superhydrophobic materials. The micro-nano rough structure has great influence on the superhydrophobicity, and the micro-dissolution cotton fabric can realize the stable load of nanoparticles. In this regard, we prepared multifunctional fabrics with an all-weather self-healing superhydrophobic layer and photocatalytic self-cleaning properties by spraying TiN and TiO2 on micro-dissolution-treated polypyrrole/cotton fabrics. The results show that the modified fabrics maintain superhydrophobicity even in harsh environments (water contact angle (WCA) up to 160.0°, water sliding angle (WSA) as low as 3.9°), with excellent abrasion resistance and stability. Even after the fabric loses superhydrophobicity due to ion etching, the superhydrophobicity can be quickly restored by photothermal or electrothermal treatment in 13 min. At the same time, the prepared multifunctional fabrics have hydrophobic and oleophilic properties, and possess good oil-water separation efficiency (98.8 %). After being contaminated by oil, the WCA recovers from 135.0° to 160.0° via the photocatalytic property of the fabric. In addition, the fabrics exhibit excellent de-icing effects. This research provides new opportunities to extend the life of superhydrophobic textiles with all-weather self-healing properties.

Superhydrophobic/superoleophilic polyurethane /reduced graphene oxide/ sponge for efficient oil-water separation and photothermal remediation

Due to the rapid development of global industrialization, the frequent occurrence of organic matter leakage and oil leakage accidents has led to increasingly serious environmental pollution. Therefore, this paper has proposed a facile and affordable method for creating oil water separation materials, and successful creating a super hydrophobic/super oleophilic functional porous polyurethane sponge modified by reduced graphene oxide and polydopamine (PDA-rGO-PU). Dopamine undergoes a self-polymerization event that creates polydopamine, which is subsequently coated on a polyurethane framework to create a sponge structure with several active sites. The surface of the modified sponge structure was coated with graphene oxide by a simple drop-coating method, and graphene oxide coated on the surface of polydopamine was reduced to create the superhydrophobic/superoleophilic material. The PDA-rGO-PU demonstrated strong anti-adhesion properties and a high oil-water separation efficiency of 99.8 % while having high water contact angles of 155 ° ± 3 ° and oil contact angles (OCA) of 0 °. It has a strong ability to adsorb various oils and organic solvents, the excellent photothermal effect allows PDA-rGO-PU to raise temperature by 37.9 % in the presence of light. PDA-rGO-PU has good continuous oil sorption performance after installing the pump. When under simulated lighting conditions, the sorption time of modified sponge on crude oil was shortened by 2.3 times.

Fabricated pH-responsive sponge with switchable wettability for multitasking and controllable oil-water separation

pH-responsive smart materials with switchable wettability have a great potential application in bidirectional oil-water separation. In this work, a simple, low-cost and environmentally friendly strategy is developed to construct a pH-responsive melamine sponge (MS) with reversible wettability via polydopamine (PDA) modification followed by grafting long-chain alkanes with carboxyl (–COOH) and methyl (–CH3) groups. The as-modified sponge exhibits unique pH-responsiveness, that is, the water contact angle (WCA) is measured to be 144.9° under acidic and neutral environments, while the wettability is radically changed from hydrophobic to hydrophilic under alkaline conditions. Moreover, in alkaline environment, the pH-responsive sponge can rapidly release the absorbed oil, demonstrating a controllable desorption performance. Also, the prepared sponge is utilized to accomplish controllable separation of various oil/water mixtures, as well as to effectively separate oil-in-water emulsions. Furthermore, after 50 cycles, the oil-water separation efficiency was still higher than 92 %. This smart wettability sponge has an extensive application prospect in controlled oil-water separation and on-demand oil-spill remediation.

A superhydrophobic PVDF-based membrane containing Metal-organic framework for efficient Oil-water separation

The discharge of oily wastewater has caused heavy burden to the environment, so it is necessary to solve this problem. Membrane separation, as a simple and efficient separation technology, has attracted widespread attentions in the field of oil–water separation. In this work, a superhydrophobic PVDF-based membrane containing MOFs with small size (ZJU-64-CH3-S) was prepared. ZJU-64-CH3-S with different amounts (200 mg, 400 mg and 600 mg) were added into PVDF to obtain ZJU-64-CH3-S/PVDF membranes, which named as M1, M2 and M3. They displayed ideal hydrophobicity according to the large water contact angle (about 130°). And composite membranes showed good oil adsorption and excellent oil–water separation efficiency. In particularly, the oil flux of M2 reached to 333.33 L/(m2·h) and its oil–water separation efficiency was as high as 99 %. The composite membrane was expected to be used in the field of oil–water separation.

Super-hydrophilic membranes fabricated by synergistic integration of covalent organic framework nanoflowers and hydrophilic layers for efficient oil-water separation

Despite numerous advancements, the development of super-hydrophilic membranes for efficient oil-water separation remains a significant challenge due to issues such as membrane fouling and the trade-off between selectivity and permeability. This study addresses these issues by innovatively integrating covalent organic framework nanoflowers with hydrophilic layers of polydopamine and polyethylene glycol. The research introduces a novel membrane, DP/COF3/PVDF, fabricated through a layer-by-layer self-assembly process and subsequent co-deposition of dopamine and PEG, which combines the nanostructured COF with a hydrophilic coating. Experimental results reveal that the optimized membrane exhibits remarkable hydrophilicity, with a water contact angle of 17.0° and an underwater oil contact angle of 176.9°. Notably, the membrane achieves an impressive pure water flux of 3919.9 L m−2 h−1 bar−1 and a rejection rate exceeding 98.0 % across various oil-water emulsions, significantly outperforming traditional membranes. The membrane exhibits superior antifouling capabilities and stability over ten cycles of use, with negligible flux decline and consistent rejection rates, showcasing robust durability and reusability. This study's findings highlight the potential for developing next-generation super-hydrophilic membranes with improved oil-water separation efficiency and durability.

Preparation of robust superhydrophobic stainless steel mesh for Oil-Water separation through Mn-Assisted control of one-step electrodeposited Zn growth

Removing oil spills from water presents a significant challenge in environmental remediation. Among various separation materials available, superhydrophobic materials have emerged as promising solutions, notable for their efficiency, cost-effectiveness, and eco-friendliness. The precise control of micro/nanostructure synthesis plays an essential role in creating superhydrophobic surfaces. Herein, the present study demonstrates controlled growth of well-defined hexagonal platelet-like micro/nanostructures of zinc crystals. This is achieved through deliberate manipulation of the electrodeposition crystal growth process, a facet frequently disregarded in previous studies. Notably, the present work, based on the distinctive properties of the Zn hexagonal close-packed structure (hcp), focuses on the effects of incorporating Mn and deposition parameters on the performance of Zn coatings. These findings offer valuable insights into selectively constructing Zn crystal planes for future electrodeposition endeavors. The resulting zinc/manganese stearate (SZM) coating on stainless steel mesh (SSM) shows remarkable water contact angles, reaching an impressive 163.1 ± 2.4°, in accordance with the Cassie-Baxter theory. This feature facilitates highly efficient oil–water separation. Coupled with size sieving of SSM, SZM coatings exhibit an oil–water separation efficiency of up to 99.86 % and a flux as high as 55.58 kL/m2h. Furthermore, the SZM coating exhibits long-lasting superhydrophobicity and exceptional corrosion resistance, even when subjected to challenging conditions such as high temperatures up to 200℃, pressure reaching 7 kg/cm2, or exposure to chemical and mechanical stresses. These enduring properties make SZM coatings suitable for constructing gravity-based and continuous oil–water separation systems, establishing them as a practical solution for diverse oil–water separation applications.

Ultra-hydrophilic MOF-303 on electrospun nanofibers with Burr Puzzles structure for the purification of oily wastewater containing heavy metal ions

The current oil-water separation field is extremely complex and the material system is variable. Therefore, the full process applicability of membrane technology is extremely demanding, both in terms of high oil-water separation efficiency and the treatment of soluble substances in wastewater, such as heavy metal ions. The high demand for membrane performance is accompanied by the complexity of the membrane manufacturing process, resulting in the development of membrane technology being hindered. If we can purify heavy metal ions from wastewater while meeting the conditions of oil-water treatment, and simplify the process flow, it is an innovation that we are happy to see. Herein, the use of a seed pre-embedded growth strategy is taking polyacrylamide (PEI) as a breakthrough point, we take advantage of blending to introduce embedding sites in polyacrylonitrile (PAN) membranes. Uniform growth of MOF-303 with Burr Puzzle structure on membrane surface using in situ hydrothermal growth method. The Burr Puzzles structure on the membrane surface is not only able to effectively deal with nanoscale stabilized oil-water mixture and effectively adsorb heavy metal ions, but also enables the MOF-303 crystals to grow more firmly on the membrane surface, so that the modified membrane still maintains good performance in harsh environments. The separation fluxes of the oil-in-water emulsions were all higher than 6987 L m−2 h−1 for oil-in-water emulsion with a separation efficiency of 98.4 %, and the adsorption efficiency of heavy metal ions was also as high as 98.3 %. After 20 cycles, the membrane maintains its promising performance. Due to its simple preparation process and excellent efficiency of emulsions separation and heavy metal ions separation, simplifies complex membrane processes while meeting the rigors of wastewater treatment. it has great prospects for development in the current complex wastewater treatment process.

Microcellular foaming-derived strong ultra-high molecular weight polyethylene/high-density polyethylene foams for thermally insulating and oil-water separating applications

Ultra-high molecular weight polyethylene (UHMWPE) has excellent weather & chemical corrosion, abrasive resistances, and hydrophobicity, endowing UHMWPE foams promising perspectives in many applications, such as thermal insulation and oil-water separation, especially in harsh environment. However, the preparation of UHMWPE foams presents significant challenges due to its exceedingly high melt strength. In this study, a self-enhancement strategy was developed to tailor the melt viscoelasticity and foaming behavior of UHMWPE by blending with high-density polyethylene (HDPE). Remarkably, the inclusion of 40 wt% HDPE contributes to the achievement of the maximum expansion ratio reported to date for the UHMWPE foam, up to 36.5, and meanwhile, significantly expanded the foaming temperature range. The incorporation of HDPE notably improved the mechanical properties of the UHMWPE foams. With 30 wt% HDPE, the compressive strength and modulus of the foams increased by 50.9 % and 109.9 %, respectively. The foams with 40 wt% HDPE also demonstrated superior thermal insulation, exhibiting a thermal conductivity as low as 39.81 mW·m⁻¹·K⁻¹, marking a 92 % reduction compared to pure UHMWPE. Furthermore, the open-cell structure of the UHMWPE/HDPE composite foams displayed exceptional oil-water separation efficiency. This study introduces an innovative, eco-friendly approach for crafting UHMWPE foams tailored for multifunctional applications in harsh environmental conditions.

Development of superhydrophobic PVA/CNC nanofibrous membranes for enhanced oil-water separation

Effective oil–water separation is crucial for environmental purification and the remediation of oil pollution, yet current methods face limitations in efficiency, durability, and environmental impact. In this study, we aimed a green nanofibrous membrane with excellent oil–water separation efficiency, addressing the significant environmental challenge of separating oil from water in various states. For this purpose, polyvinyl alcohol (PVA)-based nanofibers were prepared by aqueous electrospinning. The mechanical strength of the nanofibers was reinforced by adding cellulose nanocrystals (CNCs). The surface of the nanofibers was modified with hexadecyltrimethoxysilane (HDTMS) to induce hydrophobicity, evidenced by the increase in contact angle from 44.41° to 133.19°, facilitating effective oil separation from various states, including dispersed, suspended, and emulsified states. The prepared PVA/CNC-HDTMS nanofiber showed 194 %, 539 %, and 407 % higher tensile strength, yield strength, and Young’s modulus than PVA nanofibers, respectively. The oil sorption capacity of the nanofibers varied widely from 17.01-113.76 g/g, which is strongly influenced by the viscosity and volatility of the oil species. The durability and reusability of the nanofibers were well maintained, even after being reused more than 10 times without morphological deterioration. In separating oil–water mixtures, the nanofibers maintained a high flux of 40,039 L/m2h and a separation efficiency of 99.2 % under pressurized conditions. Additionally, the nanofibers achieved a separation efficiency of 98.5 % in oil–water emulsion states.

Surface modification of polyester fabrics for improving oil–water separation efficiency using air pressure plasma without any additives

Surface modification of polyester fabrics for improving oil–water separation efficiency using air pressure plasma without any additives

Advancing oil-water separation: Design and efficiency of amphiphilic hyperbranched demulsifiers

Hypothesis: An innovative strategy for designing high-performance demulsifiers is proposed. It hypothesizes that integrating mesoscopic molecular simulations with macroscopic physicochemical experiments can enhance the understanding and effectiveness of demulsifiers. Specifically, it is suggested that amphiphilic hyperbranched polyethyleneimine (CHPEI) could act as an efficient demulsifier in oil–water systems, with its performance influenced by its adsorption behaviors at the oil–water interface and its ability to disrupt asphaltene-resin aggregates.Experiments: Several coarse-grained models of oil–water systems, with CHPEI, are constructed using dissipative particle dynamics (DPD) simulation. Following the insights gained from the simulations, a series of CHPEI-based demulsifiers are designed and synthesized. Demulsification experiments are conducted on both simulated and crude oil emulsions, with the process monitored using laser scanning confocal microscopy. Additionally, adsorption kinetics and small angle X-ray scattering are employed to reveal the inherent structural characteristics of CHPEI demulsifiers.Findings: CHPEI demonstrates over 96.7 % demulsification efficiency in high acid-alkali-salt systems and maintains its performance even after multiple reuse cycles. The simulations and macroscopic experiments collectively elucidate that the effectiveness of a demulsifier is largely dependent on its molecular weight and the balance of hydrophilic and hydrophobic groups. These factors are crucial in providing sufficient interfacial active functional groups while avoiding adsorption sites for other surfactants. Collaborative efforts between DPD simulation and macroscopic measurements deepen the understanding of how demulsifiers can improve oil–water separation efficiency in emulsion treatment.

Realization of oil/bacteria-containing effluent purification and self-power for water monitoring based on solar-driven interfacial evaporation

Low-energy separation techniques are urgently needed to obtain clean water from complex effluent sources, especially in light of the increasing global water and energy shortages. Herein, we proposed a de novo integrated strategy that simultaneously achieved the purification of oil/bacteria-containing complex wastewater/seawater while generating self-power for monitoring the quality of purified water via solar-driven water evaporation (SDWE) of effluent utilizing a modified MXene-based aerogel (M@PCM-4). This aerogel featured a vertically aligned porous cellular microchannel structure, and it possessed photothermal conversion and self-power functions. Our study demonstrates high oil–water separation efficiency (>99.75 %), bacterial retention rate (∼100 %), and power generation (0.22 V), which holds practical significance. The designed strategy offered a potential route for addressing the dual challenges of clean water scarcity and sustainable energy production.

Study on the influence of different factors on the performance of centrifugal supergravity oil-water separator

As the development of oil fields progresses, an increasing number of fields are entering high water-cut stages.Onsite oil-water separation and wastewater reinjection are crucial for reducing water treatment loads and energy consumption in crude oil transportation. Traditional oil-water separators suffer from issues such as large size and low separation efficiency. Therefore, this paper investigates a highly efficient centrifugal supergravity oil-water separator. Numerical simulations examined the impact of flow parameters, structural parameters, and physical properties on the separator’s flow field and performance. The research findings reveal that the oil-water separation efficiency decreases with an increase in water content. As the inlet flow increased, the oil content at the water outlet continuously rose. With an increase in motor speed, the separation efficiency initially increased and then stabilized. Within the simulated range, the number of blades was positively correlated with the separation effect, while the blade ripple radius, oil density, and viscosity were negatively correlated with the separator's effectiveness. An increase in orifice diameter caused fluctuations in the separation effect and the oil content at the water outlet.

Ultra flexible silica aerogel with excellent mechanical properties for durable oil-water separation

Flexible Silica aerogel has a broad application prospect in the field of oil-water separation due to its low density and high porosity. However, its poor mechanical properties limit its application and it is a challenge to improve its mechanical properties while maintaining its excellent oil absorption capacity. In this work, we add silica sol to the silica source system formed by vinyltrimethoxysilane (VTMS) and vinylmethyl dimethoxysilane (VMDMS) to prepare silica sol-reinforced flexible silica aerogels by ambient pressure drying. The introduction of silica sol provides more -OH groups that can be used as condensation sites. The hydrolysis products of VTMS and VMDMS undergo dehydration condensation reaction with these exposed -OH groups and co-polymerize, resulting in a more robust three-dimensional porous structure. Silica sol- reinforced vinyl flexible silica aerogel is prepared with excellent mechanical properties. Its maximum strain can reach 80 % in 10 compression-decompression cycles without destroying its structure. Its hydrophobic angle was 145.7 °. Most particularly, compared to conventional flexible aerogel,when the silica sol-reinforced vinyl flexible silica aerogel is used in oil-water separation applications, it does not need to be dried after absorbing oil but only mechanically squeezed to expel the absorbed organic solvent. It can be reused hundreds of times, which greatly improves the efficiency of oil-water separation.