Oil Spill Remediation Research Articles

Superoleophilic polyurethane sponge for highly efficient oil/water separation

A superoleophilic polyurethane sponge had been constructed by means of an immersion method in an ethanol solution of n-octadecyltrichlorosilane. SEM, FTIR, TGA, and XPS unanimously confirmed that PODS had been successfully coated onto the skeleton of polyurethane sponge. The PODS-modified sponge displayed both excellent hydrophobicity with high water contact angle of 152° and good oil affinity. The PODS-modified sponge took the high adsorptive capabilities for the silicone oil, toluene, and peanut oil with 62.1, 73.7, and 98.2 g · g–1 after 50 cycles of extrusion-release, respectively. The superoleophilic sponge in this work exhibited promising opportunities on the oil/water separation and the oil spill remediation.

Multimodal Characterization of the Oleophilic Hydrophobic Magnetic (OHM) Sponge: A Nanocomposite Material for Oil Spill Remediation

Multimodal Characterization of the Oleophilic Hydrophobic Magnetic (OHM) Sponge: <i>A Nanocomposite Material for Oil Spill Remediation</i>

Integrated Omics Elucidate the Mechanisms Driving the Rapid Biodegradation of Deepwater Horizon Oil in Intertidal Sediments Undergoing Oxic-Anoxic Cycles.

Crude oil buried in intertidal sands may be exposed to alternating oxic and anoxic conditions but the effect of this tidally induced biogeochemical oscillation remains poorly understood, limiting the effectiveness of remediation and managing efforts after oil spills. Here, we used a combination of metatranscriptomics and genome-resolved metagenomics to study microbial activities in oil-contaminated sediments during oxic-anoxic cycles in laboratory chambers that closely emulated in situ conditions. Approximately 5-fold higher reductions in the total petroleum hydrocarbons were observed in the oxic as compared to the anoxic phases with a relatively constant ratio between aerobic and anaerobic oil decomposition rates even after prolonged anoxic conditions. Metatranscriptomics analysis indicated that the oxic phases promoted oil biodegradation in subsequent anoxic phases by microbially mediated reoxidation of alternative electron acceptors like sulfide and by providing degradation-limiting nitrogen through biological nitrogen fixation. Most population genomes reconstructed from the mesocosm samples represented uncultured taxa and were present typically as members of the rare biosphere in metagenomic data from uncontaminated field samples, implying that the intertidal communities are adapted to changes in redox conditions. Collectively, these results have important implications for enhancing oil spill remediation efforts in beach sands and coastal sediments and underscore the role of uncultured taxa in such efforts.

Phase-selective gelators based on benzene 1,3,5-tricarboxamide for aromatic solvents recovery and dye removal

ABSTRACT Three supramolecular gelators (2a, 3a, 3b) of a benzene 1,3,5-tricarboxamide (BTA) motif were synthesized and studied for their gelation behavior. 3a and 3b were designed and synthesized for the first time. 3a showed excellent gelation behavior in a variety of aromatic solvents with minimum gel concentration in the range of 0.7% (w/v)–2.1% (w/v). The morphology of the stable gels indicated the formation of a highly entangled fiber network in mesitylene and xylene. FT-IR studies revealed an evident role of intermolecular hydrogen bonding in the self-assembly process. UV studies showed that π–π interaction is the driving force for the gelator to form a gel. The experiment results of the aromatic solvents recovery showed that the BTA-based gelator with naphthyl group exhibits excellent phase selectivity on gel mesitylene and xylene from a mixture of aromatic solvent and water when applied in the powder form at 3.2% (w/v) in mesitylene and 4.2% (w/v) in xylene. π-π stacking between phenyl groups and naphthyl groups of gelator might provide an additional driving force for the formation of a dense three-dimensional network capable of phase-selective gelation of aromatic solvents from a mixture of aromatic solvent and water. The experiment results of the dye removal indicated that the entangled fibrous network and the rheological property enable the BTA-based phase-selective gelator to be used as recyclable materials for removing toxic dyes from a mixed solution of water and organics with efficiency as high as 99.5%. And 3a can gel crude oil from a mixture of water and oil by using crude oil as carrier solvents. Thus, these smart systems possess the potential to be used effectively in water purification and oil spills remediation.

An environmentally benign ionic liquid based formulation for enhanced oil spill remediation: Optimization of environmental factors

Formulations based on ionic liquids (ILs) have emerged as potential alternatives to conventional dispersants for remediating the effect of oil spills. However, the performance of such IL formulations is greatly affected by various environmental factors. The present study developed a model that correlates the wave-mixing energy, temperature and salinity with the dispersion effectiveness for a formulation comprising an IL surfactant and a biosurfactant using response surface methodology. The experimental results were fitted with a second-order quadratic model; the analysis of variance showed good correlation between the experimental and predicted data with a R2 value of 0.9968. The maximum dispersion effectiveness was found to be 88.4% at the optimized conditions of a stirring rate of 242 rpm, temperature of 28.3 °C and salinity of 3.4 wt% with an experimental error of <2.0%. Crude oil samples dispersed at these optimized conditions were examined by optical microscopy and dynamic light scattering, and fine droplets with sizes of <300 nm were observed. The results of this work will improve the understanding of the effects of specific environmental factors on this new formulation and assist in oil spill response planning and decision making.

Microwave- and Formaldehyde-Assisted Synthesis of Ag-Ag3PO4 with Enhanced Photocatalytic Activity for the Degradation of Rhodamine B Dye and Crude Oil Fractions.

The release of crude oil and water-soluble dyes into our marine environment is a major global problem. An efficient semiconductor Ag–Ag3PO4 photocatalyst was synthesized using formaldehyde as a reducing agent to form surface active Ag on Ag3PO4 under microwave radiation for heating, and its potential in destroying environmental pollutants has been examined. The diffuse reflectance spectroscopy of Ag–Ag3PO4 revealed an enhanced absorption in the visible light region. The rate of photocatalytic degradation of rhodamine B by Ag–Ag3PO4 was over 4-fold compared to Ag3PO4. The potential application of Ag–Ag3PO4 in oil spill remediation was also examined through photocatalytic degradation of benzene, n-hexane, and 1:1 v/v benzene/methanol crude oil-soluble fractions. UV–vis and gas chromatography–mass spectrometry analysis of the crude oil components after visible light irradiation showed excellent degradation. The photocatalytic efficiency enhancement of Ag–Ag3PO4 is attributed to the excellent electron trapping of silver nanoparticles deposited on the surface of Ag3PO4. This work will motivate future studies to develop recyclable visible light photocatalysts for many applications.

Sustainable Reuse of Char Waste for Oil Spill Recovery Foams

The aim of this work is the employment of char waste in the synthesis of silicon foams for oil spill remediation and the comparison analysis with carbon nanotubes-filled foams. The foams are obtained by foaming a slurry constituted by a silicone matrix with CNT or char filler (7.7 wt%) in presence of a Sn-based catalyst. All the investigated materials present a foam morphology with an open/closed cell structure. Each foam was tested in three used common oils (kerosene, crude oil, and pump oil). Also, hydrophilic behavior of the foam was investigated. CNT showed a 700% sorption capacity in light oils (almost 7 goil/gfoam in kerosene); on the contrary, char foam evidenced the higher sorption efficiency in heavier oils; in particular, it reaches 130% in pump oil (1.3 goil/gfoam). All the filled foams are reusable. The reuse increases the foam efficiency and decreases the economic and environmental impacts.

Fishing for oil

THE SEAS HAD TURNED ROUGH as a sudden squall whipped up the winds enough to howl through the rigging. And with those winds came a powerful smell of oil. Soon I could see the characteristic rainbow sheen from my position on the rail of this fishing trawler. It was May of 2016, and we were in the Gulf of Mexico, about 16 kilometers off the southeast coast of Louisiana. · Skimmer in the water, bellowed Kevin Kennedy, an Alaskan fisherman turned oil-spill remediation entrepreneur. Ropes groaned as the boat's winches lowered his prototype oil-recovery system into the heaving seas. As the trawler bobbed up and down, Kennedy's contraption rode the waves, its open mouth facing into the slick, gulping down a mix of seawater and crude oil. u The stomach of Kennedy's device, to continue the analogy, was a novel separator, which digested the mixture of seawater and oil. By virtue of its clever engineering, it excreted essentially nothing but water. At the top of the separator's twin tanks, the collected oil began to swell. When enough had accumulated, the oil was sucked safely into a storage tank. Then the cycle would begin again.

Oil spill remediation from water surface using induction of magnetorheological behavior in oil by functionalized sawdust

Protecting the environment is important for its impact on the life of humans and organisms. Oil pollution is one of the most important factors affecting the life of creatures. Here we are looking for the way to magnetize oil contamination by modified sawdust. The iron oxide nanoparticles were coated in situ on the sawdust using co-precipitation method, which magnetized the sawdust. Subsequently, the magnetic sawdust was successfully functionalized with a saline coupling agent to form a highly hydrophobic and oleophilic surface. FE-SEM, FTIR, EDXA, VSM, WCA and optical microscopy were performed to complete characterization of the products. In addition, a new magnetorheological (MR) fluid based on the crude oil and magnetized sawdust was developed and its rheological properties studied by a rheometer furnished with a magnetic field generator. The results were completely fitted using Bingham model. The strong MR response induced in the crude oil by adding the modified sawdust could exhibit a high crude oil removal capacity of about 47 times the modified sawdust weight.

Assessing the Location of Ionic and Molecular Solutes in a Molecularly Heterogeneous and Nonionic Deep Eutectic Solvent.

Deep eutectic solvents (DES) are emerging sustainable designer solvents viewed as greener and better alternatives to ionic liquids. Nonionic DESs possess unique properties such as viscosity and hydrophobicity that make them desirable in microextraction applications such as oil-spill remediation. This work builds upon a nonionic DES, NMA–LA DES, previously designed by our group. The NMA–LA DES presents a rich nanoscopic morphology that could be used to allocate solutes of different polarities. In this work, the possibility of solvating different solutes within the nanoscopically heterogeneous molecular structure of the NMA–LA DES is investigated using ionic and molecular solutes. In particular, the localized vibrational transitions in these solutes are used as reporters of the DES molecular structure via vibrational spectroscopy. The FTIR and 2DIR data suggest that the ionic solute is confined in a polar and continuous domain formed by NMA, clearly sensing the direct effect of the change in NMA concentration. In the case of the molecular nonionic and polar solute, the data indicates that the solute resides in the interface between the polar and nonpolar domains. Finally, the results for the nonpolar and nonionic solute (W(CO)6) are unexpected and less conclusive. Contrary to its polarity, the data suggest that the W(CO)6 resides within the NMA polar domain of the DES, probably by inducing a domain restructuring in the solvent. However, the data are not conclusive enough to discard the possibility that the restructuring comprises not only the polar domain but also the interface. Overall, our results demonstrate that the NMA–LA DES has nanoscopic domains with affinity to particular molecular properties, such as polarity. Thus, the presented results have a direct implication to separation science.

Synergistic effect of Zr/Cl dual-ions mediated pyrrole polymerization and development of superhydrophobic melamine sponges for oil/water separation

Accidental oil spills and concomitant water contaminations are prevalent during offshore oil production in the petroleum industries. Therefore, the development of hydrophobic and oleophilic sorbents is paramount for effective separation and recovery of oil. In the present work, we report the fabrication of a superhydrophobic/oleophilic melamine-formaldehyde sponge (MFS) by a facile one-step solution immersion route for effective separation of oil-water mixtures. Here we show that Zr4+/Cl- ionic pairs originate from ZrCl4 plays a synergistic role for polymerization of pyrrole (Py) and structure modification of MFS. Firstly, the pristine MFS surface is encapsulated by PPy via Cl-ions induced auto polymerization of pyrrole (Py) monomers. Secondly, Zr-ions modify the triazine ring structure of pristine MFS by the formation of Zr-N ligands confirmed by X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy analysis. The simultaneous surface and structure modification of pristine MFS leads to the formation of a superhydrophobic sponge exhibiting contact angle ∼162.6° on a static water droplet and outstanding absorption capacity (∼100-110 times) for a wide range of oils and organics solvents. Importantly, the flexible superhydrophobic sponge found reusable for multiple times with oil retention remains ∼93–95% up to the 20th cycle. In summary, a benign one-step solution immersion route is identified for developing superhydrophobic sponges for oil-spill remediation.

Influence of Spent Engine Oil Pollution and Organic Amendment on Soil Physicochemical Properties, Microbial Population and Growth of Capsicum annuum (L.)

This study investigated the impacts of spent engine oil on the physicochemical properties of soil, soil's microbial population and growth of Capsicum annuum. It covered assessment of different levels of contamination (0, 20, 40, 60 and 80%) in soil; which represents the degree of oil spillage concentration on the growth performance of C. annuum investigated. Percentage germination, seedling height, number of leaves and number of branches decreased as the concentrations of the spent engine oil in soil samples increased and affected soil physicochemical properties. The screening experiment conducted showed that poultry manure improved the physicochemical properties of sandy loam soils contaminated engine oil. The effects of poultry manure as an organic amendment was assessed using pepper (C. annuum) as test crop. All amendment made significant increase in soil organic carbon and calcium content over the polluted soils. Soil acidity increased, soil exchangeable ions decreased. N, P and K were altered in the polluted soils as compared to the controls. There were increased bacterial counts (2.21 – 2.85) and a decrease in fungi population (0.48 - 0.59) in the spent engine oil-contaminated soils compared with the control. The oil reduced germination percentage, depressed growth, reduction in leaf number and plant height of the C. annuum. Therefore the spent engine oil clearly had detrimental effects on soil's physicochemical and biological properties. The oil contributed largely to the extreme acidic nature of the polluted soils. However, maximum increase in plant height, germination percentage, number of leaves and branches were recorded with amendment of the polluted soils with poultry manure. Results show the considerable potential of remediation protocols with poultry manure as a remediating agent for oil spill remediation in the soil samples.

Adsorption of Petroleum Fractions on Organo-Modified Calcium Bentonite

This work aims to obtain an organoclay from a local Nigerian bentonite with Cetyl trimetyl-Ammonium bromide (CTAB), a quaternary ammonium compound which possesses surfactant properties. The studied natural bentonite (calcium bentonite) was obtained from Anambra state and modified with CTAB via impregnation techniques. Modification was achieved by varying the concentration of the modifier from 0.02 - 0.15mol/L. Adsorption test was carried out using Water, Petrol (PMS), Kerosene (DPK) and Automotive Gas Oil (AGO) on both modified and unmodified bentonite. The result showed that unmodified bentonite adsorbed more water than hydrocarbons while Modified bentonite adsorbed more hydrocarbons than water. The result also shows that the amount of each hydrocarbon adsorbed increases with an increase in the concentration of the modifier with a subsequent decrease in the amount of water adsorbed. This indicates that the modified bentonite was now organophilic. Therefore, this research shows that the bentonite modified with CTAB can be used in oil spill remediation and also to mop up hydrocarbons from the Environment.

Photothermal hierarchical carbon nanotube/reduced graphene oxide microspherical aerogels with radially orientated microchannels for efficient cleanup of crude oil spills

High viscosity and low fluidity of heavy crude oils usually hinder their rapid diffusion into porous adsorbents, causing a low efficiency of oil spill remediation. Photothermal effect is thus adopted to rapidly reduce the viscosity of heavy crude oil by in situ solar light heating. Photothermal carbon nanotube/reduced graphene oxide (CNT/RGO) microspherical aerogels are synthesized by fabrication of graphene oxide (GO)-based microspherical aerogels with numerous radially orientated microchannels, followed by growing CNTs inside the microchannels and high-temperature reduction of the GO components. Thanks to the efficient photothermal conversion effect and the rough and oleophilic surface of the microchannels with large surface area, such aerogels facilitate the solar light absorption and hence enhance the crude oil adsorption. Furthermore, the CNTs grown on the RGO skeleton by a chemical vapor deposition approach promote the photothermal conversion efficiency by trapping and absorbing broadband solar light. Under 1 sun irradiation, the surface temperature of the aerogel quickly rises to 83 °C in 1 min, resulting in a sharp decrease in crude oil viscosity. The optimal microspherical aerogels deliver an extraordinary adsorption capacity of heavy crude oil, up to 267 g g−1 within 10 min, superior to those of other oil adsorbents reported so far.

Development, formulation and optimization of a novel biocompatible ionic liquids dispersant for the effective oil spill remediation

The application of chemical dispersants in marine oil spill remediation is comprehensively reported across the globe. But, the augmented toxicity and poor biodegradability of reported chemical dispersants have created necessity for their replacement with the bio-based green dispersants. Therefore, in the present study, we have synthesized five ionic liquids (ILs) namely 1-butyl-3-methylimidazolium lauroylsarcosinate, 1,1’-(1,4-butanediyl)bis(1-H-pyrrolidinium) dodecylbenzenesulfonate, tetrabutylammonium citrate, tetrabutylammonium polyphosphate and tetrabutylammonium ethoxylate oleyl ether glycolate, and formulated a water based ILs dispersant combining the synthesized ILs at specified compositions. The effectiveness of formulated ILs dispersant was found between 70.75% and 94.71% for the dispersion of various crude oils ranging from light to heavy. Further, the acute toxicity tests against zebra fish and grouper fish have revealed the practically non-toxic behaviour of formulated ILs dispersant with LC50 value greater than 100 ppm after 96 h. In addition, the formulated ILs dispersant has provided excellent biodegradability throughout the test period. Overall, the formulated new ILs dispersant is deemed to facilitate environmentally benign oil spill remediation and could effectively substitute the use of hazardous chemical dispersants in immediate future.

Potential Application of Dioctyl Sodium Sulfosuccinate Salt (DOSS)–Saponin Binary Dispersant in Oil Spill Remediation: Synergistic Interaction Between DOSS and Saponin

The interfacial activity of dispersants can be enhanced by combining two or more surfactants to formulate the dispersant. This paper examines the effects of Bio-Saponin (BS), a phytogenic surfactant on the interfacial activity of synthetic dioctyl sulfosuccinate sodium salt (DOSS) usually adopted as a suitable surface-active agent in dispersants used in dealing with large-scale oil spills. The o/w emulsion created with the binary DOSS-BS was very stable and recorded the least average droplet size compared with that of DOSS only and BS only. Lower surface and interfacial tension values were also obtained from the DOSS-BS binary formulation. The dispersion effectiveness was also higher compared with that of DOSS and BS. However, they were dependent on the salinity and type of crude oil. These observations were attributed to the moderation of the interaction between the anionic head group of DOSS by the polysaccharide hydrophilic group of BS. The results revealed the potential application of DOSS-BS binary dispersant in oil spill remediation and in other processes that would require an effective emulsifier.

Molecular Transformation of Crude Oil Contaminated Soil after Bioelectrochemical Degradation Revealed by FT-ICR Mass Spectrometry.

Bioremediation is a low-cost approach for crude oil spill remediation, but it is often limited by electron acceptor availability. In addition, the biodegradation products of crude oil contaminants are complex, and transformation pathways are difficult to decipher. This study demonstrates that bioelectrochemical systems (BESs) can be effective in crude oil degradation by integrating biological and electrochemical pathways, and more importantly, it provides the first understanding on the daughter products of bioelectrochemical hydrocarbon degradation. Using electrospray ionization (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) and two-dimensional gas chromatography (GC × GC), the results showed that the active BES reactor improved the total petroleum hydrocarbon (TPH) degradation by ∼70% than open circuit control reactors. After separating the daughter products into nine fractions (MA1-MA9) according to the molecular weight (m/z 200-1000) by modified aminopropyl silica (MAPS) fractionation, we found that active BES remediation resulted in 50% more polar, oxygen-containing naphthenic (NAP) acids. The MA4 fraction (centered at ∼550 Da) increased by 47%, and MA5 and MA7 fractions with higher molucular weight increased by a maximum of ∼7- and 9-fold, respectively. These results are in accordance with the variation of bulk elemental compositions in O2 species, where daughter transformation products doubled relative to parent oil extract. The contribution of newly generated NAP acids was mainly from higher-order oxygen species (O5-O6) with increased hydrophobicity in conjunction with a decreased abundance in lower-order oxygen species (O1). Overall, the study suggests that n-alkane degradation occurred via β-oxidation to oxygenated transformation products with lower molecular weight, such as n-alcohols in O1 class and subsequently to n-fatty acids in O2 class.

Photocatalytic degradation of fractionated crude oil: potential application in oil spill remediation

The current oil spill remediation strategies are costly and may be toxic to aquatic species and clean-up workers. There is, therefore, the need to look for alternative oil spill remediation strateg...

Mandelic acid-derived organogelators: applications of their solid form in rapid and efficient remediation of marine oil spills

Phase-selective gelation of crude oil in gelator solid form was achieved using a mandelic acid-derived organogelator for the instant and efficient remediation of marine oil spills.

Chitosan–Starch Films Modified with Natural Extracts to Remove Heavy Oil from Water

Chitosan films were used to remove heavy oil from connate water, deionized water, and seawater. In this research, chitosan–starch films were modified with natural extracts from cranberry, blueberry, beetroot, pomegranate, oregano, pitaya, and grape. These biodegradable, low-cost, eco-friendly materials show an important oil sorption capacity from different water conditions. It was observed that the sorption capacity has a clear correlation with the extract type, quantity, and water pH. In order to understand the physical and chemical properties of the films, they were analyzed according to their apparent density, water content, solubility, and swelling degree by scanning electron microscopy (SEM), thermogravimetric analysis (TGA), gas chromatography–mass spectroscopy (GC–MS), and the determination of surface area using the Brunauer Emmett Teller (BET) method. The results indicate that chitosan–starch films modified with natural extracts can be successfully applied for environmental issues such as oil spill remedy.