Environmental-friendly and magnetic/silanized ethyl cellulose sponges as effective and recyclable oil-absorption materials

Functional nanocellulose hydrogel with amino acid integration for enhanced Li/Fe separation in LiFePO4 batteries

With the rising prevalence of lithium-ion batteries, efficient recovery of metal ions, particularly those potentially released from LiFePO4 anodes, has become critical. Given that both Fe3+ and Li+ ions can form electrostatic adsorptive interactions, achieving effective separation of conventional adsorbent materials becomes challenging. This study presents an amino acid-functionalized nanocellulose hydrogel (ANH) synthesized by incorporating L-threonine, which significantly enhances the selective adsorption of Fe3+ in a mixed-ion environment by leveraging coordination differences between Li+ and Fe3+. The morphology, functional groups, and pore structure of ANH were extensively characterized using scanning electron microscopy, Fourier transform infrared spectroscopy, and mercury intrusion porosimetry techniques. Through batch experiments, the adsorption thermodynamics and isotherms of ANH for Fe3+ were examined. Furthermore, the adsorption selectivity of ANH for Li+ and Fe3+ was evaluated in a mixed-ion system, revealing that the adsorption capacity for Fe3+ was four times higher than for Li+ at elevated concentrations. The adsorption mechanism of Li+/Fe3+ was elucidated through multi-scale simulations, and the influence of varying amino acid grafting degree on adsorption metrics, such as solvent-accessible area and hydrogen bonding numbers, was investigated. The combination of experimental and theoretical results demonstrates the potential of ANH to inform the development of high-performance, selective adsorbents.

Functionalization of cellulose-based sponges: Design, modification, environmental applications, and sustainability analysis

The trend of economic globalization is accelerating, and as competition for resources intensifies within the international community, there is an urgent need to seek environmentally friendly renewable resources. Sponges, due to their excellent inherent properties, have significant potential for applications in various fields. While considerable attention has been given to the synthesis of inorganic and plastic/rubber-based sponges in recent years, research on cellulose-based sponges (CBSs) has been on the rise. This review provides an overview of recent advances related to CBSs, detailing their structure and properties, including structural design, functional modification, and applications. An extensive sustainability analysis comparing CBSs with inorganic and plastic/rubber sponges shows that CBSs offer superior sustainability. The review also explores the latest applications of CBSs in environmental science, such as catalysts, dye removal, oil-water separation, ion removal, and seawater evaporation. Overall, this review highlights the inherent advantages of CBSs and encourages the exploration of their broader application areas.

Electrospun composite membranes of ethyl cellulose and MXene (Ti3C2Tx): Biocompatible platforms for enhanced drug delivery and antibacterial wound healing

Ethyl cellulose (EC), a degradable cellulose derivative, served as a primary component in membranes fabricated by electrospinning for in vitro drug delivery applications. An effective strategy to enhance drug release was incorporating high-surface-area nanomaterials into polymeric drug carriers, which facilitated drug attachment to both the polymer matrix and additive surfaces, promoting release. MXene (Ti3C2Tx) demonstrated promising potential in improving tensile mechanical properties, antibacterial activity, and curcumin (Cur) release performance of EC membrane. Compared to Cur-loaded EC/MXene membranes, the toughness of Cur-loaded EC-based carriers significantly increased by 53.58 %, reaching 3.821 kJ/m3. This composite membrane exhibited exceptional antibacterial efficacy, notably reducing Staphylococcus aureus colonies by 52.4 × 107 CFU/mL after 168 h, through the dilution spread plate method. Using MTT assay, the composite membrane demonstrated biocompatibility, as evidenced by >70 % viability of mouse fibroblast L929 cells with observable cell attachment after 168 h. Importantly, the EC/MXene membrane achieved a Cur release amount of 69.82 % compared to 7.11 % from Cur-loaded EC membranes within 168 h, representing a 62.71 % enhancement in Cur release. The EC/MXene composite membrane is a promising drug delivery candidate, particularly for Cur, by utilizing the sustainability of EC as the primary drug carrier component.

Inside-out templating: A strategy to decorate helical carbon nanotubes and 2D MoS2 on ethyl cellulose sponge for enhanced oil adsorption and oil/water separation

Ethyl cellulose (EC)-based composite sponges were developed for oil spillage treatment. The EC sponge surface was decorated with helical carbon nanotubes (HCNTs) and molybdenum disulfide (MoS2) (1 phr) using the inside-out sugar templating method. The inside surface of a sugar cube was coated with HCNTs and MoS2. After filling the sugar cube pores with EC and the subsequent sugar leaching, the decorating materials presented on the sponge surface. The EC/HCNT/MoS2 sponge had a high level of oil removal based on its adsorption capacity (41.68 g/g), cycled adsorption (∼75-79 %), separation flux efficiency (∼85-95 %), and efficiency in oil/water emulsion separation (92-94 %). The sponge maintained adsorption capacity in acidic, basic, and salty conditions, adsorbed oil under water, and functioned as an oil/water separator in a continuous pump-assisted system. The compressive stress and Young's modulus of the EC sponge increased following its decoration using HCNTs and MoS2. The composite sponge was robust based on cycled compression and was thermally stable up to ∼120 οC. Based on the eco-friendliness of EC, the low loading of HCNTs and MoS2, and sponge versatility, the developed EC/HCNT/MoS2 sponge should be good candidate for use in sustainable oil adsorption and separation applications.

Microsponges-mediated targeted topical delivery of rosemary oil for hair growth promotion: optimization and in-vivo studies

Individuals experiencing hair loss, irrespective of gender, confront significant psychological challenges. This study explores the untapped potential of rosemary oil (ROS) to stimulate hair growth, addressing its limited permeability. The focus is on innovating ROS-loaded microsponges (MS) for enhanced topical application. Utilizing Box-Behnken design (33), the study optimizes ROS-MS compositions by varying solvent volume, polymer mix, and drug concentration. The optimized ROS-MS formulation exhibits noteworthy attributes: a 94% ± 0.04 production yield, 99.6% ± 0.5 encapsulation efficiency, and 96.4% ± 1.6 cumulative ROS release within 24 h. These microsponges exhibit uniformity with a particle size of 14.1 µm ± 4.5. The OPT-ROSMS-gel showcases favorable characteristics in appearance, spreadability, pH, drug content, and extrudability. Ex-vivo skin deposition tests highlight heightened permeability of OPT-ROSMS-gel compared to pure ROS-gel, resulting in three-fold increased follicular retention. In-vivo studies underscore the superior efficacy of OPT-ROSMS-gel, revealing enhanced hair development in length, thickness, and bulb diameter, surpassing ROS-gel and minoxidil by approximately 1.2 and 1.5 times, respectively, along with nearly two-fold increase in β-catenin levels. In conclusion, microsponges emerge as a promising ROS delivery method, effectively addressing hair loss. This research advances hair loss treatments and underscores the significance of this innovative paradigm in fostering hair growth.

A solvent-template ethyl cellulose-polydimethylsiloxane crosslinking sponge for rapid and efficient oil adsorption

Lipophilic adsorbents for oil-water separation are usually synthesized using the template method, in which hydrophobic materials are coated on a ready-made sponge. Herein, a novel solvent-template technique is used to directly synthesize a hydrophobic sponge, by crosslinking polydimethylsiloxane (PDMS) with ethyl cellulose (EC) which plays a vital role in the formation of 3D porous structure. The as-prepared sponge has advantages of strong hydrophobility, high elasticity, as well as excellent adsorption performance. In addition, the sponge can be readily decorated by nano-coatings. After the sponge was simply dipped in nanosilica, the water contact angle increases from 139.2° to 144.5°, and the maximum adsorption capacity for chiroform rises from 25.6 g/g to 35.4 g/g. The adsorption equilibrium can be reached within 3 min, and, the sponge can be regenerated by squeezing, without any change in hydrophobility or evident decline in capacity. The simulation tests of emulsion separation and oil-spill cleanup demonstrate that the sponge has great potential in oil-water separation.

Recent Advances in Biomass-Based Materials for Oil Spill Cleanup

Oil spill on sea surfaces, which mainly produced by the oil leakage accident happened on tankers, offshore platforms, drilling rigs and wells, has bring irreversible damage to marine environments and ecosystems. Among various spill oil handling methods, using sorbents to absorb and recover spill oils is a perspective method because they are cost-effective and enable a high recovery and without secondary pollution to the ecosystem. Currently, sorbents based on biomass materials have aroused extensively attention thanks to their features of inexpensive, abundant, biodegradable, and sustainable. Herein, we comprehensively review the state-of-the-art development of biomass-based sorbents for spill oil cleanup in the recent five years. After briefly introducing the background, the basic theory and material characteristics for the separation of oil from water and the adsorption of oils is also presented. Various modification methods for biomass materials are summarized in section three. Section four discusses the recent progress of biomass as oil sorbents for oil spill cleanup, in which the emphasis is placed on the oil sorption capacity and the separation efficiency. Finally, the challenge and future development directions is outlined.

Modified cotton fabric based on thiolene click reaction and its oil/water separation application

A cotton fabric with special wettability was prepared in two simple steps. The surface of the fabric was grafted with silicon-oxygen group using 3-(methacryloyloxy) propyl trimethoxysilane (MSPMA) as the reagent, and then (3-mercaptopropyl)triethoxysilane (MPTES) was used to react with the grafted fabric under ultraviolet light according to the principle of thiolene reaction. Meanwhile, the modified cotton fabrics with various pore sizes were obtained via modifying the cotton fabric with different pore size under the same experimental conditions. The as-prepared fabric had a better hydrophobic and lipophilic effect, whose water contact angle could be up to 146.7° and the separation efficiency for different kinds of oil/water mixtures was better than 94%. In addition, the pore sizes of cotton fabrics had a great effect on the rate of oil/water separation, which increased with the increase of the pore size.

Recent advances and future perspective on nanocellulose-based materials in diverse water treatment applications

Over the past few years, nanocellulose and its derivatives have drawn attention as promising bio-based materials for water treatment applications due to their high surface area, high strength, and renewable, biocompatible nature. The abundance of hydroxyl functional groups on the surfaces of cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) enables a broad range of surface modifications which results in propitious nanocomposites with tunable characteristics. In this context, this review describes the continuously developing applications of nanocellulose-based materials in the areas of adsorption, catalysis, filtration, and flocculation, with a special emphasis on the removal of contaminants such as heavy metals, dyes, and pharmaceutical compounds from diverse water systems. Recent progresses in the diverse forms of application of nanocellulose adsorbents (suspension, hydrogel, aerogel, and membrane) are also highlighted. Finally, challenges and future perspectives on emerging nanocellulose-based materials and their possible industrial applications are presented and discussed.

A Modified Porous Sponge with Selective Ability for Oil Removal from Oil-Water Mixtures

As oil and chemical spills pose a significant threat to the water environment, the need to develop efficient sorbent materials to remove oil and organic pollutants from water has arisen. This study aimed to develop a simple modification scheme to impart oil and water selective absorption capacity to a common three-dimensional porous material. Commercially available polyurethane sponges were used as the base material, and vinyl silica aerogel particles were loaded onto the sponges using polydimethylsiloxane as an adhesion agent. As a result, the water contact angle of the modified sponge increased from 118° to 149.2°, and the water absorption decreased from 106.5 g/g to 0.2 g/g; it could absorb oil in oil-water mixtures without absorbing water and maintain an excellent level of selective absorption ability after 20 cycles. This modification scheme is easy to operate and robust and is a scheme of practical application.

Bio-Based Aerogel Based on Bamboo, Waste Paper, and Reduced Graphene Oxide for Oil/Water Separation

In recent years, the discharge of industrial waste oil has increased and offshore oil leakage has occurred frequently, and thus water pollution has become a worldwide problem that attracts much attention. In this regard, a kind of oil-absorbing material with high oil-absorbing property and good mechanical property is urgently needed. Here, we reported a new type of aerogels with three-dimensional layered voids using natural bamboo powder, waste paper (WP), and graphene oxide (GO) as raw materials. The obtained aerogel had high adsorption capacity (87-121 g/g), compressibility, and high elasticity, which can separate oil from water and selectively absorb oil. This study provides not only a new treatment in agricultural waste treatment but also a facile, green, and low-cost approach to synthesize high-performance graphene-based oil absorbers, which might give us an effective solution for oil pollution of water resources worldwide.

Recent Progress in Modification Strategies of Nanocellulose-Based Aerogels for Oil Absorption Application

Oil spills and oily wastewater have become a major environmental problem in recent years, directly impacting the environment and biodiversity. Several techniques have been developed to solve this problem, including biological degradation, chemicals, controlled burning, physical absorption and membrane separation. Recently, biopolymeric aerogels have been proposed as a green solution for this problem, and they possess superior selective oil absorption capacity compared with other approaches. Several modification strategies have been applied to nanocellulose-based aerogel to enhance its poor hydrophobicity, increase its oil absorption capacity, improve its selectivity of oils and make it a compressible and elastic magnetically responsive aerogel, which will ease its recovery after use. This review presents an introduction to nanocellulose-based aerogel and its fabrication approaches. Different applications of nanocellulose aerogel in environmental, medical and industrial fields are presented. Different strategies for the modification of nanocellulose-based aerogel are critically discussed in this review, presenting the most recent works in terms of enhancing the aerogel performance in oil absorption in addition to the potential of these materials in near future.

Fabrication and Characterization of Hydrophobic Cellulose Nanofibrils/Silica Nanocomposites with Hexadecyltrimethoxysilane

Cellulose nanofibrils (CNFs) have attracted much attention because of their renewability and potential biocompatibility. However, CNFs are extremely hydrophilic due to the presence of a large number of hydroxyl groups, limiting their use as a water-resistant material. In this work, we controlled the adsorption behavior of silica nanoparticles on the surface of CNFs by adjusting the synthesis conditions. The silica nanoparticle size and packing efficiency on the CNF surface could be controlled by varying the ammonium hydroxide and water concentrations. In addition, hexadecyltrimethoxysilane (HDTMS) was successfully grafted onto CNF or CNF/silica nanocomposite surfaces, and the quantitative content of organic/inorganic substances in HDTMS was analyzed through XPS and TGA. The HDTMS-modified CNF/silica nanocomposites were more advantageous in terms of hydrophobicity than the HDTMS-modified CNF composites. This is because the silica nanoparticles were adsorbed on the surface of the CNFs, increasing the surface roughness and simultaneously increasing the amount of HDTMS. As a result, the HDTMS-modified CNFs showed a water contact angle (WCA) of ~80°, whereas HDTMS-modified CNF/silica nanocomposites obtained superhydrophobicity, with a WCA of up to ~159°. This study can provide a reference for the expansion of recyclable eco-friendly coating materials via the adsorption of silica nanoparticles and hydrophobic modification of CNF materials.

Versatile Route for Multifunctional Aerogels Including Flaxseed Mucilage and Nanocrystals

Preparation of low density monolithic and free-standing organic-inorganic hybrid aerogels of various properties is demonstrated using green chemistry from a biosafe natural source (flaxseed mucilage) and freeze-casting and subsequent freeze drying. Bio-aerogels, luminescent aerogels and magneto-responsive aerogels were obtained by combination of the flaxseed mucilage with different types of nanoparticles. Moreover, the aerogels are investigated as possible drug release system using curcumin as a model. Various characterization techniques like thermogravimetric analysis, nitrogen physisorption, electron microscopy, UV/Vis absorption and emission spectroscopy, bulk density and mechanical measurements as well as in vitro release profile measurements are employed to investigate the obtained materials. The flaxseed-inspired organic-inorganic hybrid aerogels exhibit ultra-low densities of as low as 5.6 mg/cm³ for 0.5% (w/v) mucilage polymer, a specific surface area of 4 to 20 m² /g, high oil absorption capacity (23 g/g) and prominent compressibility. The natural biopolymer technique leads to low cost and biocompatible functional lightweight materials with tunable properties (physicochemical and mechanical) and significant potential for applications as supporting or stimuli responsive materials, carriers, reactors, microwave, and electromagnetic radiation protective (absorbing) material as well as in drug delivery and oil absorption. This article is protected by copyright. All rights reserved.

Recent Progresses in Eco-Friendly Fabrication and Applications of Sustainable Aerogels from Various Waste Materials

Tons of waste from residential, commercial and manufacturing activities are generated due to the growing population, urbanization and economic development, prompting the need for sustainable measures. Numerous ways of converting waste to aerogels, a novel class of ultra-light and ultra-porous materials, have been researched to tackle the issues of waste. This review provides an overview of the status of aerogels made from agricultural waste, municipal solid, and industrial waste focusing on the fabrication, properties, and applications of such aerogels. The review first introduced common methods to synthesize the aerogels from waste, including dispersion and drying techniques. Following that, numerous works related to aerogels from waste are summarized and compared, mainly focusing on the sustainability aspect of the processes involved and their contributions for environmental applications such as thermal insulation and oil absorption. Next, advantages, and disadvantages of the current approaches are analyzed. Finally, some prospective waste aerogels and its applications are proposed.

Current Status of Cellulosic and Nanocellulosic Materials for Oil Spill Cleanup

Recent developments in the application of lignocellulosic materials for oil spill removal are discussed in this review article. The types of lignocellulosic substrate material and their different chemical and physical modification strategies and basic preparation techniques are presented. The morphological features and the related separation mechanisms of the materials are summarized. The material types were classified into 3D-materials such as hydrophobic and oleophobic sponges and aerogels, or 2D-materials such as membranes, fabrics, films, and meshes. It was found that, particularly for 3D-materials, there is a clear correlation between the material properties, mainly porosity and density, and their absorption performance. Furthermore, it was shown that nanocellulosic precursors are not exclusively suitable to achieve competitive porosity and therefore absorption performance, but also bulk cellulose materials. This finding could lead to developments in cost- and energy-efficient production processes of future lignocellulosic oil spillage removal materials.

Double-network cross-linked aerogel with rigid and super-elastic conversion: simple formation, unique properties, and strong sorption of organic contaminants

Novel adsorbents with high adsorption capacity, broad-spectrum adsorption performance, and good reusability are needed for the treatment of diverse and complex contaminants in water. In this work, we used in situ hydrothermal reaction to fabricate graphene oxide (GO) and poly(vinyl alcohol) (PVA) based aerogels (GP_XA, X represented the volume of PVA) through the cross-linking network that meets the above requirement. After adding Ca²⁺, GP₁₆A (with 16 mL PVA) had surprisingly rigid and super-elastic conversion that is dependent on water stimulus. The strong adsorption of methylene blue (MB) on GP₁₆A illustrated that it had excellent dye removal ability. The adsorption capacity of GP₁₆A to MB was 698.38 mg g^-1 and it remained 85.62% after repeated adsorption-desorption cycles. The adsorption was controlled by multiple mechanisms including electrostatic interaction, π-π interaction, and hydrogen bond. In addition, hydrophobically modified GP₁₆A (GP₁₆A-MTMS) effectively absorbed common oils and organic solvents. Repeated absorption of GP₁₆A-MTMS was re-activated by squeezing operation. This study provides an alternative technique for preparing aerogel materials with high recyclability, dimensional stability, and solvent resistance, and for dealing organic contaminants in water.

Cellulose supported magnetic nanohybrids: Synthesis, physicomagnetic properties and biomedical applications-A review

Cellulose and its forms are widely used in biomedical applications due to their biocompatibility, biodegradability and lack of cytotoxicity. It provides ample opportunities for the functionalization of supported magnetic nanohybrids (CSMNs). Because of the abundance of surface hydroxyl groups, they are surface tunable in either homogeneous or heterogeneous solvents and thus act as a substrate or template for the CSMNs' development. The present review emphasizes on the synthesis of various CSMNs, their physicomagnetic properties, and potential applications such as stimuli-responsive drug delivery systems, MRI, enzyme encapsulation, nucleic acid extraction, wound healing and tissue engineering. The impact of CSMNs on cytotoxicity, magnetic hyperthermia, and folate-conjugates is highlighted in particular, based on their structures, cell viability, and stability. Finally, the review also discussed the challenges and prospects of CSMNs' development. This review is expected to provide CSMNs' development roadmap in the context of 21st-century demands for biomedical therapeutics.

Nanocellulose: a bioadsorbent for chemical contaminant remediation

Chemical contaminants such as heavy metals, dyes, and organic oils seriously affect the environment and threaten human health. About 2 million tons of waste is released every day into the water system. Heavy metals are the largest contributor which cover about 31% of the total composition of water contaminants. Every day, approximately 14 000 people die due to environmental exposure to selected chemicals. Removal of these contaminants down to safe levels is expensive, high energy and unsustainable by current approaches such as oxidation, biodegradation, photocatalysis, precipitation, reverse osmosis and adsorption. A combination of biosorption and nanotechnology offers a new way to remediate these chemical contaminants. Nanostructured materials are proven to have higher adsorption capacities than the same material in its larger-scale form. Nanocellulose is very promising as a high-performance bioadsorbent due to its interesting characteristics of high adsorption capacity, high mechanical strength, hydrophilic surface chemistry, renewability and biodegradability. It has been proven to have higher adsorption capacity and better binding affinity than other similar materials at the macroscale. The high specific surface area and abundance of hydroxyl groups within lead to the possible functionalization of this material for decontamination purposes. Several research papers have shown the effectiveness of nanocellulose in the remediation of chemical contaminants. This review aims to provide an overview of the most recent developments regarding nanocellulose as an adsorbent for chemical contamination remediation. Recent advancements regarding the modification of nanocellulose to enhance its adsorption efficiency towards heavy metals, dyes and organic oils were highlighted. Moreover, the desorption capability and environmental issue related to every developed nanocellulose-based adsorbent were also tackled.

Construction of a hydrophobic magnetic aerogel based on chitosan for oil/water separation applications

Hydrophobic/oleophilic absorbents have been largely studied and used in recovering spilled oil. However, they still suffer from several drawbacks and two of them are poor biocompatibility and hard to thoroughly rinse. In order to address these problems, here a hydrophobic magnetic chitosan-based aerogel is fabricated via electrostatic interactions between chitosan (CS), itaconic acid (IA) and Fe₃O₄ nanoparticles and dip-coating in ethanol solution of Candelilla wax (CW). Due to the interconnected porous structure of chitosan-based aerogel, the magnetism of Fe₃O₄ nanoparticles and the hydrophobicity of CW, the prepared aerogel exhibits high absorption capacities (from 17.7 to 43.8 g/g) towards various types of organic liquids, excellent magnetic controllability with saturation magnetization of 15.93 emu/g and good water repellency with water contact angle (WCA) of 147.9°. In addition, the aerogel can also continuously separate immiscible oil/water mixtures and water-in-oil emulsions as the form of filter. More significantly, the absorbed organic liquids can be completely recovered by simply placing the aerogel in water solution of IA at 75 °C, which can avoid cleaning agent consumption. As a consequence, this renewable, biodegradable and eco-friendly oil scavenger presents a bright prospect in practical applications.

Magnetic nanocellulose-magnetite aerogel for easy oil adsorption

HYPOTHESIS

Cellulose aerogels are a new category of high-efficiency adsorbents for treating oil spills and water pollution. However, the hydrophilic properties and recyclability of aerogels after adsorption hamper developments and applications. Combining both hydrophobic and magnetic properties are expected to improve their adsorption capacity and functionality.

EXPERIMENTS

In this study, the effect of oleic acid (OA) and nanomagnetite on the preparation of magnetic nanocellulose aerogels (called as NCA/OA/Fe₃O₄) by a mechanical mixing combined with freeze-drying method have been investigated.

FINDINGS

It has been found that the optimal condition for fabricating this NCA/OA/Fe₃O₄ aerogel is 0.4 wt% nanocellulose, 3 mg mL^-1 OA and 0.5 wt% Fe₃O₄ in the aqueous solution. This aerogel has a very low density of 9.2 mg cm^-3 and demonstrates a high adsorption capacity of 68.06 g g^-1 for cyclohexane. In addition, this aerogel adsorbent demonstrates an excellent magnetic responsivity and can be easily recycled by a permanent magnet after adsorption. As a consequence, this hydrophobic magnetic NCA/OA/Fe₃O₄ aerogel is promising not only for easy oil and organic solvent adsorption but also potentially for other magnetic related applications.

An ultra-light flexible aerogel-based on methane derived CNTs as a reinforcing agent in silica-CMC matrix for efficient oil adsorption

Bamboo shaped multi-walled Carbon Nanotubes were synthesized by the thermo-catalytic decomposition of methane in a modified chemical vapour deposition reactor. The prepared carbon nanotubes were reinforced in the mero-hydrophobic carboxymethyl cellulose and silica matrix for the preparation of low density, highly flexible aerogel. The synthesized aerogel exhibited a large specific surface area and uniform pore structure as confirmed by the nitrogen adsorption-desorption analysis. The water contact angle of 148.8° for the aerogel demonstrated that the synthesized aerogels were superhydrophobic in nature. The performance of aerogels was tested for the adsorption of singer oil and motor oil. Investigations revealed that aerogel can adsorb more than 28 times its weight effectively. Moreover, the adsorbed oil can be recovered by mechanical squeezing owing to its flexible nature. In addition, the aerogel could maintain its oil adsorption capacity even after 5 regeneration cycles, demonstrating superior recyclability. The peculiar properties - outstanding flexibility and superhydrophobicity exhibited by the aerogels establish them as a proficient and recyclable oil adsorbents during the oil seepage.

Controllable synthesis of pomelo peel-based aerogel and its application in adsorption of oil/organic pollutants

Oil/water separation is a field of high significance as it might efficiently resolve the contamination of industrial oily wastewater and other oil/water pollution. In this paper, an environmentally-friendly hydrophobic aerogel with high porosity and low density was successfully synthesized with renewable pomelo peels (PPs) as precursors. Typically, a series of sponge aerogels (HPSA-0, HPSA-1 and HPSA-2) were facilely prepared via high-speed dispersion, freeze-drying and silanization with methyltrimethoxysilane. Indeed, the physical properties of aerogel such as density and pore diameter could be tailored by different additives (filter paper fibre and polyvinyl alcohol). Hence, their physico-chemical properties including internal morphology and chemical structure were characterized in detail by Fourier transform infrared, Brunauer-Emmett-Teller, X-ray diffraction, scanning electron microscope, Thermal gravimetric analyzer (TG) etc. Moreover, the adsorption capacity was further determined and the results revealed that the PP-based aerogels presented excellent adsorption performance for a wide range of oil products and/or organic solvents (crude oil 49.8 g g^-1, soya bean oil 62.3 g g^-1, chloroform 71.3 g g^-1 etc.). The corresponding cyclic tests showed the absorption capacity decreased slightly from 94.66% to 93.82% after 10 consecutive cycles, indicating a high recyclability.

Construction of hydrophobic alginate-based foams induced by zirconium ions for oil and organic solvent cleanup

Hydrophobic modification of sodium alginate (SA) foams via a simple freeze-drying and post cross-linking induced by zirconium (Zr) ions was developed. All results demonstrated that Zr ions not only constructed surface microstructure but also lowered surface energy of foams, leading to the hydrophobic character. Hydrophobic and oleophilic foams showed excellent adsorption capacities for different oils and organic solvents (11.2-25.9 g/g). Furthermore, SA solution can be also coated on porous substrates, such as melamine sponges (MS) and Nylon strainers (NS), to give hydrophobic modification by Zr ion crosslinking. These excellent performances made them a promising for oil adsorption and cleanup.

Biomimetic fabrication of superhydrophobic loofah sponge: robust for highly efficient oil-water separation in harsh environments

Oil/water separation has become an increasingly important field due to frequent industrial oily wastewater emission and crude oil spill accidents. Herein, we fabricate a robust superhydrophobic loofah sponge via a versatile, environmentally friendly, and low-cost dip coating strategy, which involves the modification of commercial loofah sponge with waterborne polyurea and fused SiO2 nanoparticles without the modification of any toxic low-surface-energy compound. The as-prepared loofah sponge showed excellent superhydrophobic/superoleophilic properties and exhibited robustness for effective oil-water separation in extremely harsh environments (such as 1 M HCl, 1 M NaOH, saturated NaCl solution and hot water higher than 95 °C) due to the remarkably high chemical stability. In addition, the as-prepared loofah sponge was capable of excellent anti-fouling, has self-cleaning ability and could act as the absorber for effective separation of surfactant-free oil-in-water emulsions. More importantly, the as-prepared loofah sponge demonstrated remarkable robustness against strong sandpaper abrasion and finger wipes, while retaining its superhydrophobicity and efficient oil/water separation efficiency even after more than 50 abrasion cycles. This facile and green synthesis approach presented here has the advantage of large-scale fabrication of a multifunctional biomass-based adsorbent material as a promising candidate in anti-fouling, self-cleaning, and versatile water-oil separation.

Magnet-responsive, superhydrophobic fabrics from waterborne, fluoride-free coatings

Durable superhydrophobic fabrics with magnetic response ability have been prepared by waterborne, fluoride-free coatings.

Synthesis of aminopyridine-containing conjugated microporous polymers with excellent superhydrophobicity for oil/water separation

Aminopyridine-containing conjugated microporous polymer based membranes with excellent superhydrophobicity for continuous oil/water separation on a large scale.