β-Cyclodextrin-based oil-absorbent microspheres: Preparation and high oil absorbency

Electrochemically fast preparation of superhydrophobic copper mesh for high-efficiency oil spill adsorption and oil-water separation

Oily wastewater and marine oil spills are a massive environmental and human threat. Conventional oil spill treatment methods include adsorption by absorbent materials, dispersants or adsorbents, and in situ burning. Superhydrophobic materials, as a material that can achieve oil-water separation, have great potential for application in oil spill treatment. Research on superhydrophobic oil spill treatment mainly focuses on materials such as sponges and fabrics. Although these materials can effectively perform oil-water separation or oil spill adsorption, they also have the disadvantages of complicated preparation methods and high costs. Here, we present a miniature device for oil-water separation and oil spill collection and recovery. The superhydrophobic copper mesh box can be used on its own as an oil-water separation device or in combination with a commercial polyurethane sponge as a miniature oil-absorbing device. The robust copper mesh is prepared in two steps: anodizing and impregnation. The superhydrophobic copper mesh had a high oil separation flux (32,330 L m-2 h-1) and efficiency (97%), which remained high (28,560 L m-2 h-1) and efficient (95%) after 20 cycles of separation. The combined micro oil adsorption device can adsorb different oils and fats on the water surface, and it has good reusability with oil adsorption capacity and efficiency up to 15.28 g/g and 98% and still has good oil adsorption capacity (11.54 g/g) and efficiency (94.6%) after 20 cycles of adsorption. Therefore, the prepared micro oil-absorbing device has promising application prospects in oil-water separation, oil spill cleanup, etc. ENVIRONMENTAL IMPLICATION: This study demonstrates a facile electrochemical approach to prepare a miniature device for high-efficiency oil-water separation and oil spill collection and recovery. The modified copper mesh's separation flux could reach 32,330 L m-2 h-1, showing great promise in oil-water separation and oil spill cleanup.

An oil-absorbing resin with a simple polymerization system with benzyl methacrylate as a functional monomer

To solve the problem of the low absorbency of oil-absorbing resins, oil-absorbing resins (PAMs) were fabricated in this study by introducing commercially available benzyl methacrylate (BZMA) as a functional monomer copolymerized with stearyl methacrylate (SMA) and butyl acrylate (BA). The internal network structure of the PAMs expanded more easily when absorbing oils or organic solvents after introducing rigid groups of the benzene ring by an uncomplex polymerization process, which provided the oil-absorbing resin with good absorbency. The reagents were all commercially available, and there was no other pretreatment or posttreatment process. Then, the optimum parameters for the monomer feed ratio, water/oil mass ratio, and concentrations of initiator, stabilizer and crosslinker were studied. Simultaneously, the reusability, oil retention and thermal stability of PAMs were investigated in this article. The PAMs swelled in various oils and organic solvents (the values of oil absorbency were 44.52, 56.13, 25.54, 28.21, 32.85, 24.56, 14.17, 15.02 and 29.07 g g-1 for CCl4, CHCl3, CH2Cl2, benzene, toluene, xylene, n-hexane, 0# diesel oil and 93# gasoline, respectively) and displayed good oil absorbency, which met the absorption requirements for common oils or organic solvents.

A new type of magnetic molecular imprinted material combined with β-cyclodextrin for the selective adsorption of zearalenone

In this paper, a new magnetic molecular imprinted polymer–cyclodextrin (MMIP–CD) material was prepared by connecting β-cyclodextrin (CD) on the surface of a magnetic molecular imprinted polymer (MMIP) and used for the rapid and specific adsorption of zearalenone (ZEN).

Hydrophobic, Superabsorbing Aerogels from Choline Chloride-Based Deep Eutectic Solvent Pretreated and Silylated Cellulose Nanofibrils for Selective Oil Removal

Superabsorbents are highly appealing materials for use in cleaning up oil and chemical spills. However, the development of a low-cost, highly efficient superabsorbent remains a major challenge. This paper demonstrates a straightforward method of producing a cellulose nanofibril aerogel that is low-cost, ultralight, highly porous, hydrophobic, and reusable superabsorbing cellulose nanofibril aerogel from recycled waste fibers using a simple, environmentally friendly nanofibrillation treatment involving deep eutectic solvent and freeze-drying. Nanofibrillation and hydrophobic modification (silylation) of waste cellulose fibers resulted in nanofibril sponges with ultralow density (0.0029 g/cm³) and high porosity (up to 99.81%) after freeze-drying. These sponges exhibited excellent absorption performances for various oils and organic solvents and were reusable. In particular, the nanofibril aerogels showed selectivity in absorbing marine diesel oil from an oil-water mixture and possessed ultrahigh absorption capacities of up to 142.9 g/g, much higher than those of the commercial absorbent materials (i.e., polypropylene-based material) (8.1-24.6 g/g) that were used as references. The absorbed oil could easily be recovered by means of simple mechanical squeezing. In addition, the nanofibril sponges exhibited excellent reusability, maintaining a high capacity to absorb diesel oil for at least 30 cycles at 71.4-81.0% of capacity compared to a fresh absorbent. The above-mentioned advantages make cellulose nanofibril superabsorbents created from recycled waste cellulose fibers promising material for cleaning oil and chemical spills.

Advanced Sorbents for Oil-Spill Cleanup: Recent Advances and Future Perspectives

Oil sorbents play a very important part in the remediation processes of oil spills. To enhance the oil-sorption properties and simplify the oil-recovery process, various advanced oil sorbents and oil-collecting devices based on them have been proposed recently. Here, we firstly discuss the design considerations for the fabrication of oil sorbents and describe recently developed oil sorbents based on modification strategy. Then, recent advances regarding oil sorbents mainly based on carbon materials and swellable oleophilic polymers are also presented. Subsequently, some additional properties are emphasized, which are required by oil sorbents to cope with oil spills under extreme conditions or to facilitate the oil-collection processes. Furthermore, some oil-collection devices based on oil sorbents that have been developed recently are shown. Finally, an outlook and challenges for the next generation of oil-spill-remediation technology based on oil-sorbents materials are given.

Effective clean-up of organic liquid contaminants including BTEX, fuels, and organic solvents from the environment by poly(alkoxysilane) sorbents

Novel cross-linked poly(alkoxysilane)s, which can be used for the removal of organic liquid contaminants from water, were synthesized in one step, in a solvent free reaction medium, at moderately high temperature without using a catalyst. The synthesized polymers were characterized by Fourier transform infrared spectroscopy (FTIR), solid-state (13)C and (29)Si cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR), thermal gravimetric analysis (TGA) and differential scanning calorimetry (DSC) methods and elemental analysis. The swelling features of the poly(alkoxysilane)s were investigated in organic solvents and oils, such as dichloromethane, benzene, toluene, xylene, methyl tertiary butyl ether, and also some fuel derivatives, such as gasoline and euro diesel. All polymers have high-fast solvent uptake abilities, good reusability and thermal stability. The swelling features of the synthesized cross-linked polymers were evaluated by the swelling test, absorption-desorption kinetics. Thus, the results propose that cross-linked poly(alkoxysilane)s are suitable for the absorption of oil-organic pollutants from the water surface.

Synthesis and properties of the rapeseed meal-grafted-poly(methyl methacrylate-co-butyl acrylate) oil-absorbents

Economical RSMs-g-P(MMA-co-BA) oil-absorbents with 3D network structures were prepared through free radical graft copolymerization, which exhibited good oil absorbency, reusability and were applied to oil/water separation.

Poly(dimethylsiloxane) oil absorbent with a three-dimensionally interconnected porous structure and swellable skeleton

Cleanup of oil spills is a worldwide challenge to prevent serious environmental pollution. A new kind of poly(dimethylsiloxane) (PDMS) oil absorbent with high absorption capacity and excellent reusability was prepared and used for oil/water separation. The preparation process of PDMS oil absorbents involves direct curing of a PDMS prepolymer in a p-xylene solution in the presence of commercial sugar particles, which is simple and economic. PDMS oil absorbents have interconnected pores and a swellable skeleton, combining the advantages of porous materials and gels. Absorption capacities of PDMS oil absorbents are 4-34 g/g for various oils and organic solvents, which are 3 times that reported previously. Owing to their hydrophobicity and oleophilicity, the as-obtained PDMS oil absorbents can selectively collect oils or organic solvents from water. The absorption process can be finished within tens of seconds. Furthermore, the absorbed oils or organic solvents can be recovered by compressing the oil absorbents, and after 20 absorbing/recovering cycles, PDMS oil absorbents show little loss of their absorption capacities and own weights.