Open‐cell polypropylene/polyolefin elastomer blend foams fabricated for reusable oil‐sorption materials

The fabrication of high‐performance oil sorbents is of great significance for oil spill cleanup. The main objective of this study was to prepare open‐cell polypropylene/polyolefin elastomer (PP/POE) blend foams for fabrication of reusable sorbents for oil sorption. Open‐cell PP/POE blend foams were prepared via continuous‐extrusion foaming using supercritical carbon dioxide as the blowing agent. The interconnected open‐cell structure was characterized by scanning electron microscopy. The hydrophobicity and lipophilicity of PP/POE open‐cell foams were revealed by tests of contact‐angle measurement, water and cyclohexane sorption on the foam surface, CCl₄ and cyclohexane sorption in water, and oil/water separation. Further, the sorption tests indicated that PP/POE blend foams showed larger oil‐uptake capacities than pure PP foams. In addition, cyclic compression tests showed that PP/POE open‐cell foams had excellent ductility and significantly improved recoverability compared to pure PP foams. In cyclic sorption–desorption tests, the sorption kinetics was studied in terms of capacity and saturation time, showing that PP/POE foams kept larger sorption capacities for 10 cycles, with larger sorption rates and good reusability. Based on the high open‐cell content, the good hydrophobic and oleophilic properties, the high oil‐sorption capacity, the improved recoverability, the large sorption rate, and the good reusability in cyclic oil‐sorption performance, the PP/POE open‐cell foams have shown promise as potential oil sorbents in applications for oil spill cleanup. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43812.     

Sorptive sequestration of 2‐chlorophenol by zeolitic materials derived from bagasse fly ash

BACKGROUND: Water pollution by toxic organic compounds is of great concern and increasingly there are demands for effective sorbents to remove them. Bagasse fly ash, a sugar industry solid waste with disposal problems, was utilized as a source for the synthesis of zeolitic material. The efficiency of virgin and synthesized material was examined for the sorption of 2‐chlorophenol. RESULTS: Zeolitic materials have been synthesized by alkaline hydrothermal and fusion methods. Zeolite P and Analcime were the major components of the zeolitic material. These materials were characterized by XRF, PXRD, FTIR and SEM and were found to have improved morphology with new crystalline phases. Batch sorption experiments for the removal of 2‐chlorophenol by virgin and zeolitic materials were carried out to evaluate isotherm capacities and kinetics of sorption processes. The Langmuir isotherm better fits the equilibrium data which concur with physical sorption. Kinetic studies showed better correlation coefficients for pseudo‐second‐order and intraparticle diffusion model, confirming that the sorption rate was controlled by film diffusion followed by pore diffusion. Desorption studies were performed to regenerate the activity of the spent sorbents. The practical utility of sorbents was tested by column study. CONCLUSION: Bagasse fly ash, readily available at very low cost was successfully converted into zeolitic material. The synthesized zeolitic material showed enhanced capacities for the sorption of 2‐chlorophenol and can be utilized as a low cost sorbent for treatment of phenolic waste‐water. Copyright © 2011 Society of Chemical Industry     

Biodegradable porous organosilicone‐modified collagen fiber matrix: Synthesis and high oil absorbency

We used hexadecyl trimethyl ammonium bromide as a phase transfer catalyst (PTC) to enhance the effectiveness of a heterogeneous reaction system composed of collagen fiber (CF) and organosilicone modifying agents including epoxy‐polydimethylsiloxane (ES) and/or γ‐glycidoxypropylthrimethoxysilane (GS), in order to improve oil sorption behaviors of the modified products as sorbents. The effects of PTC dosage, organosilicone species or its dosage on the degree of modification of CFs were studied, and the optimum conditions were determined. Subsequently, the surface chemistry and porous structure of the prepared sorbents were thoroughly characterized, and their oil sorption behaviors were also investigated. It was confirmed that both their hydrophobicity‐oleophilicity character and pore structures could be significantly improved by introducing PTC agent and modulating the species or amount of organosilicone, resulting in improved oil sorption behaviors. In addition, the organosilicone modified CF matrix possessed acceptable reusability and biodegradability, and can be implemented as an eco‐friendly sorbent for oil spill cleanup. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46264.     

Spilled‐Oil Sorbents Prepared by Recycling of Eutrophicated Aquatic Plants

Recycling of four eutrophicated aquatic plants including Eichhornia crassipes, Herba Lysimachiae, Alternanthera philoxeroides, and Potamogeton crispus as spilled‐oil sorbents was investigated. The rough and hydrophobic structures of aquatic plants were observed by scanning electron microscopy and contact angle measurements. The four plants exhibited superior oil sorption capacities, especially the stalk of Eichhornia crassipes. Such high oil sorption was ascribed to their high capillarity and hydrophobic surface. The aquatic plants absorbed oil to reach adsorption saturation within one minute. The oil sorption capacity was significantly affected by particle size, but was hardly influenced by temperature. The results demonstrated that the aquatic plants could be applied as low‐cost and environment‐friendly spilled‐oil sorbents.     

Oil sorption behaviors of porous polydimethylsiloxane modified collagen fiber matrix

A facial and cost‐effective synthesis method of converting the leather protein solid wastes into a value‐added collagen matrix oil sorbent is successfully established for the first time. Hide powder fiber (HPF) was firstly prepared by using the pre‐tanned fleshing wastes from the leather industry, and then cross‐linked with epoxy‐terminated polydimethylsiloxane (PDMS) to produce hydrophobic collagen fiber, which was verified by the FT‐IR spectrum and contact angle analysis. Subsequently, a series of porous PDMS modified collagen‐based sorbents with roughness surface was successfully fabricated by solvent‐ and freeze‐drying methods respectively. The oil sorption capacity, sorption saturated time and retention capacity of the prepared sorbents was investigated. Combined with the SEM images, liquid displacement method and contact angle analysis, the results revealed that oil sorption capacities of the sorbent with lower pore size, higher porosity and rougher surface for silicone oil, motor oil and vegetable oil were approximate to 13.60, 12.50, and 11.92 g/g, respectively. Additionally, the sorption of oils is a quasi‐instantaneous process and also showed excellent oil retention capacity. It exhibited acceptable oil sorption performances as compared to commercial biomass sorbents. These findings indicated its potential as an eco‐friendly oil sorbent material. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42727.     

Envelopes with microplastics generated from recycled plastic bags for crude oil sorption

Oil spill accidents in marine environments and the lack of disposal of post-consumer plastic are environmental problems worldwide. This study presents a sustainable alternative for both issues through envelopes filled with microplastics (MPs) from recycled bags for the sorption of spilled crude oil. Through particle size analysis by three different sieves (4, 9, and 20 mesh), different MP sizes were characterized by scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET), density, contact angle (CA), and Fourier-transform infrared spectroscopy (FTIR). According to their sizes, the MPs were distributed in envelopes and submitted to crude oil sorption capacity and efficiency evaluation. Three MP particle sizes were obtained (from the largest to the smallest, according to the sieve mesh, MP4, MP9, and MP20). SEM images of samples exhibited irregular and porous surfaces, and MP4 had the smallest pore size (8.6 μm). BET showed that MP4 had the highest surface area (0.074 m²/g). The CA > 90° exposed that all samples were hydrophobic. FTIR spectrum demonstrated that the samples from the recycled bags were made of high density polyethylene (HDPE). The MP4 envelopes also had the best crude oil sorption results in capacity and efficiency (1.73 g/g and 68%, respectively), being a promising recycled sorbent in crude oil spillage applications.     

Microbial uptake of diesel oil sorbed on soil and oil spill clean‐up sorbents

Sorbent effects in the microbial uptake of diesel oil were determined for black cotton soil (BCS) and two oil spill clean‐up sorbents, ie peat sorb and spill sorb. Biodegradation studies were conducted in mass transfer limited batch slurry microcosms using microorganisms capable of direct interfacial uptake of diesel oil. Under identical loading conditions, the amounts of diesel oil initially loaded on the various sorbents were 178, 288 and 649 mg g^?1 for BCS, spill sorb and peat sorb, respectively. Total biodegradation of sorbed diesel was comparable for all the sorbents (45–52 mg), however, the biodegradation rates were significantly different. Peat sorb demonstrated a distinct initial lag phase, the biodegradation rate in spill sorb was initially slower, whereas biodegradation at a high rate commenced immediately for BCS. The maximum biodegradation rates observed for BCS, spill sorb and peat sorb microcosms were 7.9, 5, and 2.9 mg day^?1, respectively. Thus, the maximum biodegradation rate increased as the diesel oil loading decreased. Our results indicate that spill clean‐up sorbents have greater bioavailability limitations compared with soils and this is linked with their significantly higher loading capacity and internal porosity. Copyright © 2005 Society of Chemical Industry     

Porous Materials for Oil Spill Cleanup: A Review of Synthesis and Absorbing Properties

This paper reviews the synthesis and the absorbing properties of the wide variety of porous sorbent materials that have been studied for application in the removal of organics, particularly in the area of oil spill cleanup. The discussion is especially focused on hydrophobic silica aerogels, zeolites, organoclays and natural sorbents many of which have been demonstrated to exhibit (or show potential to exhibit) excellent oil absorption properties. The areas for further development of some of these materials are identified.     

Effective sorbing polymer materials for collecting oil and oil products

Effective sorbents based on nonwoven polymer materials have been synthesized for cleaning up oil and oil products spills from the water surface. The influence of structural characteristics of materials (a width of fabrics, a fiber diameter, a density of fiber packing in fabric) on their sorption capacity has been revealed. It has been shown that the materials based on polypropylene and polyether fibers exhibited the high sorption capacities in respect to oil and oil products.     

Investigation of the effectiveness of absorbent materials in oil spills clean up

The present study examines the absorption capacity of five different types of materials for oil spills clean up. The absorbents were a commercial cellulosic material from processed wood, a commercial synthetic organic fiber from polypropylene and three commercial types of local expanded perlite from the island of Milos. The absorption capacities of the above materials were evaluated in a wet as well as a dry environment with different types of petroleum products. The results showed that commercial types of perlite, in some cases, have absorption capacities comparable to natural and synthetic organic materials used for clean-up applications. The enhancement of the hydrophobic properties of perlite can result in better performance in a water bath. The nature of the spilled oil proved to play an important role in the selection of the proper absorbing material. Overall, the results suggested that partial substitution of commercial synthetic sorbents by mineral materials widely produced in Greece for oil spill clean-up operations is possible, given their friendliness to the environment and their local abundancy.     

Hollow carbon beads fabricated by phase inversion method for efficient oil sorption

Hollow carbon beads of around 3.0 mm in diameter were prepared by a simple phase inversion method and subsequent carbonisation. Due to the low density and hydrophobic property, the hollow carbon beads were floatable on water. Different organic solvents and oils were used to study the oil sorption properties of the carbon beads. Their toluene sorption capacity was as high as 55% of their own volume. For long-chain oil like motor oil, the hollow carbon beads still adsorbed 40% of their volume. In addition, the hollow carbon beads could be refreshed by heat treatment, and the oil sorption capacity remained the same after being recycled five times. This work provides a facile and low-cost method for preparing highly efficient carbon-based sorbents for oil spill clean-up.     

Synthesis and performance of different polyurethane foams as oil sorbents

Oil sorption (g g^?1) through different polyurethane foams has been investigated in this study. Polyurethane foams were synthesized with different additives: glycerol, propylene glycol, polyethylene glycol 400, and 1‐dodecanol. All foams were applied as sorbents of diesel, motor oil, gasoline, kerosene, and crude oil. The foams were characterized using Fourier transform infrared spectroscopy, thermogravimetry and differential scanning calorimetry, compressive resistance at 10% deformation and the elastic modulus, scanning electron microscopy, and apparent density. The best performance of oil sorption was achieved with PUF‐3, which has the greatest amount of the chain extender polyethylene glycol 400 and lowest density of all the evaluated foams. The sorption capacities (g g^?1) of PUF‐3 were 16.8 (diesel), 15.7 (gasoline), 20.7 (oil motor), 25.4 (kerosene), and 29.8 (crude oil) and 100% removal of diesel from water was achieved, approximately. The foams with chain extenders and lower density values performed better as oil sorbents. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 45409.     

Study oil/water separation property of PE foam and its improvement by in situ synthesis of zeolitic–imidazolate framework (ZIF‐8)

Herein, the oil/water separation property of four polyethylene (PE) foams with two different volume expansion ratios including 15 and 30 times was studied. We found that the PE‐30‐1 foam was the best absorbent materials among these four samples, which was also superior to the commercially available products. It demonstrated high oil absorption capacities, as well as high oil/water selectivity, which was due to its small average pore size and high porosity. In addition, this work also reports two rapid and straightforward methods to fabricate PE‐30‐1‐ZIF‐8 composite with enhanced compressive property, an encouraging absorption capacity for different organic solvents, reaching 59 times of its own weight for chloroform, as well as increased oil–water selectivity of the system. Comparing with the PE foam, the organic solvent absorption capacities for PE‐ZIF‐8‐sono composite foams were improved by 6.4%, 29%, 9.1%, and 12% for chloroform, acetone, toluene and oleic acid, respectively, while the corresponding improvement for PE‐ZIF‐8‐Me(OH) was about 7.5%, 28%, 14%, and 15%, respectively. These PE‐ZIF‐8 foams could reach the requirement for oil spill cleanup, suggesting its great potential for this type of application. POLYM. ENG. SCI., 59:1354–1361 2019. © 2019 Society of Plastics Engineers     

化学改性秸杆原料作高效吸油剂

介绍了秸杆的化学改性方法,油污染处理方法及化学改性秸杆作为高效吸油剂处理溢油污染的优点。并指出了化学改性秸杆研究的未来发展趋势。     

Effect of the decationization of brown coal from the Kansk-Achinsk Basin on the physicochemical properties of the resulting sorbents

Data are presented on the effect of the decationization of brown coal from the Kansk-Achinsk Basin with a dilute solution of hydrochloric acid on the structural characteristics of the resulting sorbents and the sorption capacities for iodine and phenol. It was found that the partial removal of metal cations (among which calcium was predominant) resulted in the formation of carbonization products with low reactivity upon steam activation. As compared with sorbents prepared from the parent coal under the same conditions, the sorbents from the decationized coal exhibited lower pore volumes, specific surface areas, and sorption capacities. To prepare efficient low-ash sorbents from decationized coal, a longer activation treatment is required.     

Vertically-aligned carbon nano-tube membrane filters with superhydrophobicity and superoleophilicity

A membrane filter possessing both superhydrophobicity and superoleophilicity is of great interest for the possible separation of oil and water. Such a filter was realized in this study by synthesizing vertically-aligned multi-walled carbon nano-tubes on a stainless steel mesh. The dual-scale structure, nano-scale needle-like tubes on the mesh with micro-scale pores, combined with the low surface energy of carbon amplified both hydrophobicity and oleophilicity. For the tests, diesel was selected as a representative of low viscosity oils. The contact angles for diesel and water were 0° and 163 ± 4°. The nano-tube filter could separate diesel and water layers, and even surfactant-stabilized emulsions. The successful phase separation of the high viscosity lubricating oil and water emulsions was also carried out. The separation mechanism can be readily expanded to a variety of different hydrophobic and oleophilic liquids. The simple nano-tube filter might be practically employed in environmental and chemical separation processes including oil spill cleanup.     

Application of Strong Porous Polymer Sheets for Superior Oil Spill Recovery

The usage of natural and synthetic sorbents in order to control oil spills is gaining increasing attention due to environmental concerns. In particular, polyolefins including polypropylene and polyethylene are the most commonly used oil sorbent materials because of their low cost but suffer from low oil absorption capacity. Attempts at trying to increase the surface‐to‐thickness ratio for improving uptake capacity makes them vulnerable to breakage and impractical for most oil spill applications. Novel super oil sorbent polymer sheets consisting of porous ultrahigh‐molecular‐weight polyethylene have been prepared. The presented sorbent exhibits extremely high uptake and retention capacities along with a mechanically strong structure. The combination of these factors as well as the cost effectiveness of the material used makes these sheets viable candidates for widespread production and utilization.     

Polypropylene fibers fabricated via a needleless melt‐electrospinning device for marine oil‐spill cleanup

Ultrafine polypropylene (PP) fibers as oil sorbents were fabricated via a needleless melt‐electrospinning device and were characterized by scanning electron microscopy and contact‐angle analysis. PP fibers of various diameters and porosities were obtained by the manipulation of the applied electrical field. The effects of the fiber diameter and porosity on the oil‐sorption capacity and oil‐retention behavior were investigated. The experimental results demonstrate that for fiber diameter on the microscale, the porosity played a paramount role in determining the oil‐sorption capacities. The maximum oil‐sorption capacity of the resulting PP fibers with regard to motor oil and peanut oil were 129 and 80 g/g, respectively; these values were approximately six to seven times that of commercial PP nonwoven fabricated through the melt‐blown method. In addition, even after seven sorption/desorption cycles, the oil‐sorption capacity of the chosen sample was still maintained around 80 g/g, and above 97%, oil could be recovered. This indicated excellent reusability and recoverability. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40080.     

Preparation and properties of sorbents from the coals of Mongolia

The textural and sorption properties of sorbents prepared by the thermal steam activation of the semicokes of brown and black coals from nine deposits of Mongolia were studied. Their properties were compared with the properties of sorbents prepared from Borodino brown coal and Kuznetsk black coal. A common extremal dependence of the volume of mesopores and the specific surface area on combustion losses was found: a maximum specific surface area of 600–700 m²/g was reached at a combustion loss of 50–60%. Among the Mongolian samples, the sorbents obtained from the brown coals of the Baganuur, Bagankhai, and Shivee Ovoo deposits exhibited the highest surface areas and sorption capacities for iodine. Nearly linear dependence of sorption capacity on specific surface area was found. The sorbents prepared from Borodino brown coals under identical conditions were characterized by a higher degree of combustion losses because of the increased concentrations of catalytically active calcium compounds in them.     

Alginate and Algal-Based Beads for the Sorption of Metal Cations: Cu(II) and Pb(II)

Alginate and algal-biomass (Laminaria digitata) beads were prepared by homogeneous Ca ionotropic gelation. In addition, glutaraldehyde-crosslinked poly (ethyleneimine) (PEI) was incorporated into algal beads. The three sorbents were characterized by scanning electron microscopy (SEM) coupled with energy dispersive X-ray analysis (EDX): the sorption occurs in the whole mass of the sorbents. Sorption experiments were conducted to evaluate the impact of pH, sorption isotherms, and uptake kinetics. A special attention was paid to the effect of drying (air-drying vs. freeze-drying) on the mass transfer properties. For alginate, freeze drying is required for maintaining the porosity of the hydrogel, while for algal-based sorbents the swelling of the material minimizes the impact of the drying procedure. The maximum sorption capacities observed from experiments were 415, 296 and 218 mg Pb g⁻¹ and 112, 77 and 67 mg Cu g⁻¹ for alginate, algal and algal/PEI beads respectively. Though the sorption capacities of algal-beads decreased slightly (compared to alginate beads), the greener and cheaper one-pot synthesis of algal beads makes this sorbent more competitive for environmental applications. PEI in algal beads decreases the sorption properties in the case of the sorption of metal cations under selected experimental conditions.