Oil Spill Cleanup Research Articles

Multi‐Fiber Blended Needle‐Punched Nonwoven With Oleophilic and Self‐Cleaning Properties for Oil Spill Cleanup

AbstractThis study investigates the self‐cleaning, oleophilic, and oil spill clean‐up properties of multi‐fiber blended needle‐punc lf‐cleaning performance of the nonwoven fabrics is influenced by the fiber composition. All samples with a low overall surface energy of 27.65–33.46 mN m−1, especially those with a reduced polar component, demonstrate superior oil sorption of 13.83–19.45 g g−1 and retention capabilities of 91.11–98.83%. Oil‐to‐water selectivity of 13.66–42.60 and oil removal efficiency of 93.18–97.71% are achieved. The initial oil recovery rate (desorption) during the first desorption cycle (D1) ranges from 78.28% to 79.88%. This recovery rate remains consistently high, between 97.38% and 99.86%, throughout the second to tenth desorption cycles (D2 to D10) for all samples. The findings demonstrate that the blending of multi‐fibers and web arrangement play a critical role in enhancing oil sorption and retention, oil selectivity, oil removal efficiency, reusability and self‐cleaning with statistically significant performance (p < 0.05).

Effects of Temperature and Agitation on the Kinetics of Vegetable Oil Adsorption onto Kapok Fiber

The unique properties of this natural fiber have sparked interest among researchers, opening possibilities for its potential use in oil spill cleanup. The oil adsorption may be influenced by temperature and agitation as revealed by past studies. This research focuses on both agitation speed at maximum of 200 rpm and temperature ranges from 30°C to 90°C in adsorption process to find an optimal condition to enhance the oil adsorption process. The analysis and characterization of kapok fiber by using scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and contact angle analysis that provided understandings into the structural and surface morphology of kapok fiber before and after oil adsorption. From the SEM morphology the kapok fiber observes the waxy surface and hollow lumen and porous structures believed can provide substantial capacity for oil storage.

Effects of Temperature and Agitation on the Kinetics of Vegetable Oil Adsorption onto Kapok Fiber

The unique properties of this natural fiber have sparked interest among researchers, opening possibilities for its potential use in oil spill cleanup. The oil adsorption may be influenced by temperature and agitation as revealed by past studies. This research focuses on both agitation speed at maximum of 200 rpm and temperature ranges from 30°C to 90°C in adsorption process to find an optimal condition to enhance the oil adsorption process. The analysis and characterization of kapok fiber by using scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), and contact angle analysis that provided understandings into the structural and surface morphology of kapok fiber before and after oil adsorption. From the SEM morphology the kapok fiber observes the waxy surface and hollow lumen and porous structures believed can provide substantial capacity for oil storage.

Fine particulate matter from burning oil and gas and associated neurological symptoms among Deepwater Horizon oil spill cleanup workers.

Burning and flaring of oil and gas following the 2010 Deepwater Horizon (DWH) oil spill generated high airborne concentrations of fine particulate matter (PM2.5). Neurological effects of PM2.5 have been previously reported, but this relationship has received limited attention in the context of oil spills. We evaluated associations between burning-related PM2.5 and prevalence of self-reported neurological symptoms during, and 1-3 years after, the DWH disaster cleanup. For 9914 DWH disaster responders in the Gulf Long-term Follow-up Study who worked on the water, we examined aggregate outcomes (central nervous system [CNS; dizziness, sweating, palpitations, nausea, or migraine/severe headache] and peripheral nervous system [PNS; tingling/numbness in extremities, blurred vision, or stumbling] symptoms) and individual symptoms (CNS and PNS symptoms, plus insomnia, vomiting, seizures, and fatigue). We estimated PM2.5 concentrations via Gaussian plume dispersion models and linked these to detailed DWH cleanup work histories. We used log-binomial regression to estimate adjusted prevalence ratios (PR) and 95% confidence intervals, accounting for age, race, ethnicity, and sex, and DWH disaster-related co-exposures to benzene, toluene, ethylbenzene, xylene, and n-hexane (BTEX-H). We examined effect measure modification by age, race, smoking, and BTEX-H exposure. During the disaster, 34% of participants experienced at least one symptom (23% CNS, 12% PNS); 1-3 years later, 30% did (19% CNS, 17% PNS). Evidence of associations with PM2.5 was most consistent for CNS symptoms (PR range: 1.17 to 1.51), although we did not observe exposure-response trends. For PNS, PR ranged from 0.96 to 1.84. Associations with PM were more apparent among those with lower BTEX-H exposure and among older workers. We found some evidence of an association between burning-related PM2.5 and prevalence of neurologic symptoms during the DWH disaster response and 1-3 years later. Understanding these relationships can inform responses to future disasters to better protect human health.

Electrospun PVC/Graphene Composite Nanosponges for Oil Spill Cleanup

Electrospun PVC/Graphene Composite Nanosponges for Oil Spill Cleanup

Development of reed-based cellulose aerogel: a sustainable solution for crude oil spill clean-up.

This study focused on fabricating a cellulose aerogel for oil spill clean-up, using common reed (Phragmites australis) as the cellulose source. The process involved isolating cellulose from reed via traditional Kraft pulping, considering the effects of key factors on the isolated cellulose content. After a two-stage HP bleaching sequence, the highest cellulose content achieved was 27.2%, with 80% ISO brightness and 1% ash content under mild Kraft pulping conditions of 30% sulfidity, 20% active alkali (AA), sustained cooking at 165°C for 3 h, and a liquor-to-reed ratio of 8 : 1. Subsequently, reed-based cellulose aerogel was fabricated via a freeze-drying method using an eco-friendly NaOH/poly(ethylene glycol) aqueous solvent system, which was then modified with methyltrimethoxysilane. The resulting aerogel exhibited remarkable characteristics, including a low density of 0.04 g cm-3, high porosity of 96%, high hydrophobicity with a water contact angle (WAC) of 141°, and a superior crude oil adsorption capacity of 35 g g-1. Comprehensive characterizations of the fabricated materials, including scanning electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis/differential scanning calorimetry, and WAC measurements, were evaluated. This interdisciplinary study explores the commercial promise of reed-based cellulose aerogel as a sustainable solution for oil spill clean-up efforts.

Development of a superhydrophobic and superoleophilic halloysite nanotube/phenyltriethoxysilane-coated melamine sponge sorbent material with high performance in supercritical CO2 atmosphere for the selective and effective oil spill cleanup and oil-water separation.

In this study, activated halloysite nanotube (HNT) and phenyltriethoxysilane (PTES) were utilized for the first time to fabricate modified HNT materials and coat them onto melamine sponge (MS) substrate in the supercritical carbon dioxide (scCO2) atmosphere. The successful coating of MS substrate was confirmed using SEM, EDS, XPS, and contact angle measurements. The drainage technique applied in the CO2 medium achieved the uniform coating of both the inner and outer surfaces of the MS. Water and oil contact angles of the fabricated sorbent material (MS-PTES) were measured as 167.1° and 0°, respectively. MS-PTES sorbent having superhydrophobic and superoleophilic properties demonstrated sorption capacities ranging from 47.6g/g to 132.2g/g for 13 different pollutants, including various petroleum products, oils, and organic solvents. Moreover, the MS-PTES sorbent material showed outstanding separation efficiency (99.99%) for the diesel-water mixture using a continuous separation process. It also displayed high selectivity for oil and organic solvent pollutants under acidic, saline, and alkaline conditions, along with excellent reusability, chemical stability, robustness, and mechanical flexibility. MS sorbent material coated with HNT-modified PTES nanoparticles, produced in the scCO2 atmosphere using the drainage technique, represents a promising solution for the removal of petroleum derivatives, oils, and organic solvents from water.

Long-term physical and biological recovery of disturbed intertidal beach habitat from simulated oil spill cleanup in Prince William Sound, Alaska.

Following the Exxon Valdez oil spill, hydraulic techniques using combinations of high-pressure and heated water were used to mobilize weathered oil from impacted shorelines. During treatment, concerns were raised over the ecological impacts of these treatment methods. We report on a long-term study comparing grain size and infaunal communities in washed and unwashed plots at unoiled beaches treated using these methods. Despite the long-term (nine-year) disruption of grain size structure, total infaunal abundance showed no significant differences between washed and unwashed plots after only one year and species diversity metrics had recovered by the third year post-treatment. Similarly, community structure appeared to have recovered by year three. Reasons for this apparent physical/biological disconnect may be related to the native lack of fine-grained sediments in the Prince William Sound system, and inherently robust infaunal reproductive and recolonizing strategies. This work has practical implications for spill response, damage assessment, and restoration.

Oil spill cleanup using EDTA-coated magnetite magnetic nanoparticles

As a result of the critical importance of crude oil in modern industrial society, oil spills, specifically those involving crude oil, generate substantial environmental and ecological difficulties. In contrast to conventional treatment approaches, nanotechnology has demonstrated its efficacy in remedying oil spills This type of pollution could occur during oil investigation, transit, or storage. This study adopted a straightforward and economical method utilizing iron oxide magnetic nanoparticles for oil spills cleanup. Magnetite Fe3O4 MNPs were synthesized using the co-precipitation technique, which involved combining ferric and ferrous ions in an alkaline solution at 80°C and a pH of 14. MNPs were characterized using X-ray diffraction (XRD), Fourier-Transform Infrared Spectroscopy (FTIR), transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and vibrating sample magnetometer (VSM). To improve their stability and efficacy, MNPs were coated with ethylenediaminetetraacetic acid (EDTA). Three samples of crude oil with different APIs (23, 28.4, and 40.3) were used to study the ability of coated MNPs for oil spill cleanup. Removal experiments were conducted at 25°C with a mass range of adsorbent (0.02-0.06 g). A neodymium magnet was utilized to extract the oil-contaminated magnetic nanoparticles from the water. The gravimetric oil removal (GOR) for APIs 23, 28.4, and 40.3 were 11.4 - 3.35, 7.19- 2.15, and 4.81 to 1.16 g/g, respectively. Experimental results demonstrated an inverse relationship between GOR and the API value, indicating that as the API value decreased, GOR increased, and vice versa. Furthermore, as the mass of the adsorbent material increased (0.02-0.06g), the GOR value decreased.

Volatile hydrocarbon exposures and immune-related illnesses among Deepwater Horizon oil spill workers.

Despite evidence from experimental studies linking some petroleum hydrocarbons to markers of immune suppression, limited epidemiologic research exists on this topic. The aim of this cross-sectional study was to examine associations of oil spill related chemicals (benzene, toluene, ethylbenzene, xylene, and n-hexane (BTEX-H)) and total hydrocarbons (THC) with immune-related illnesses as indicators of potential immune suppression. Subjects comprised 8601 Deepwater Horizon (DWH) oil spill clean-up and response workers who participated in a home visit (1-3 years after the DWH spill) in the Gulf Long-term Follow-up (GuLF) Study. Cumulative exposures to THC and individual BTEX-H constituents during the oil spill clean-up were estimated using a job-exposure matrix linking air measurement data to detailed participant work histories. Study outcomes included post-spill occurrence and/or frequency of illnesses ascertained at the home visit, including colds, flu, cold sores, pneumonia, and shingles. Frequent cold and frequent flu were defined as ≥4 colds and ≥2 episodes of flu since the spill, respectively. We examined an aggregate outcome of frequent colds, any flu, cold sores, or pneumonia since the spill. In single pollutant models, we used multivariable log-binomial regression to estimate prevalence ratios (PR) and 95% confidence intervals (CI) for associations between quartiles of THC and BTEX-H exposures with each outcome. We used quantile g-computation to estimate the joint effect of the BTEX-H mixture. We observed positive associations of increasing quartiles of THC and BTEX-H with all outcomes except shingles, with evidence of an exposure-response for most outcomes. Strongest associations were observed for frequent flu (range of PR: 1.41-1.67). The BTEX-H mixture was associated with small to modest elevations in PRs for most outcomes. This study is the first to our knowledge to demonstrate an association between oil spill BTEX-H exposures and multiple immune-related illnesses as measures of potential immune suppression. Increasing oil spill-related volatile hydrocarbon exposures may increase the risk of multiple immune-related illnesses, especially frequent cold and frequent flu. Future research on this topic using more robust measures of immune function would advance existing evidence on this relationship.

Fabrication of nanocellulose-based high-mechanical and super-hydrophobic xerogels for speedy oil absorbents

Cellulose-based porous materials are promising for various fields and preferred for sustainable development. However, the low mechanical properties and high hydrophilicity of cellulose-based xerogels had a direct influence on their application in oil absorption. To address the challenge, an environmentally friendly and economical method for synthesizing MTMS/C0.2-TOCN0.9 xerogels with high hydrophobicity and excellent mechanical strength was successfully established. In this work, shape-recoverable using nanocellulose (TOCN)-based xerogels with porous structure (porosity of 91.5–98.7 %), as well as excellent hydrophobic properties were prepared by TOCN-stabilized wet foams with physical crosslinking, ice crystal-induced phase separation and MTMS modification through simple air-drying instead of the traditional freeze-drying. At the optimized ingredients of TOCN and crosslinker (Ca2+), the xerogel (MTMS/C0.2-TOCN0.9) exhibited superior compressive performance (approximately 35 KPa) and exceptional structural stability after 50 cycles at a compression deflection of 60 %, which was still maintained at 71.5 % of the original stress. Moreover, the MTMS/C0.2-TOCN0.9 xerogel achieved stable superhydrophobicity (128.3°) and excellent oil absorption capacity (59.6 g/g), rendering it a desirable adsorbent for oil spill cleaning. Compared to the pseudo-first-order model, the pseudo-secondary model had higher validity in oil absorption kinetic theories. The MTMS/C0.2-TOCN0.9 xerogel was recyclable and nontoxic, which has the potential to promote environmental applications.

Improved superhydrophobicity of magnetic melamine sponge by aminosilane for batch and continuous oil–water separation

Continuous and efficient separation remains the thorny problem that restricts oil–water separation materials for the large-scale application of oil–water separation. A kind of magnetic melamine sponges with enhanced superhydrophobicity was fabricated by dip coating of polydopamine-modified Fe3O4 nanoparticles, (3-aminopropyl)triethoxysilane (APTES) and hexadecyltrimethoxysilane (HDTMS) on melamine sponge. The superhydrophobicity of melamine sponge was improved by adding APTES to cover hydrophilic group of polydopamine. The melamine sponge exhibited water contact angle of 158.3°, the absorption capacity of 43.2–80.7 g/g, volume utilization of 0.70–0.97 v/v and separation efficiencies of 99.6 % for oil–water mixture and 98.6 % for oil/water emulsion. The sponge could carried out in batch and continuous filter devices, and repeated oil absorption capacity could achieve 92.8–96.4 % of initial oil absorption capacity after 45 absorbing-squeezing cycles. The above performances of the as-prepared sponge suggest that it is a promising candidate for large-scale application of oil-spill cleanup and oily wastewater treatment.

Biomass-Based Sorbent with Superoleophilic from Ulva Prolifera for Oil Spill Cleanup.

In this study, we demonstrate a new all bio-based adsorbent material by treating Enteromorpho prolifera (EP) fibers with tannic acid-ferric chloride complex and then grafting hydrophobic group octadecylamine. All raw materials are easily available, low-cost, and safe. The modified EP fibers have approximately 63.4 g g-1 of oil absorption and 1.4 g g-1 of water absorption, which is an 62.8% increase in oil absorption and an 82% increase in hydrophobicity over that of untreated EP fibers, respectively, exhibiting high hydrophobicity and oleophilicity. The affinity discrimination to water and oil enables hydrophobic algae candidate materials to separate oils and water efficiently, both in an oil-water mixture and a water-in-oil emulsion. In summary, the as-synthesized modified EP demonstrates a broad application prospect in the treatment of oil spill accidents and oily wastewater.

Exploring the Potential of Recycled Polyethylene Terephthalate—Lignocellulose/Carbon Nanotube–Graphene Nanosheets an Efficient Extractor for Oil Spill

The global challenge of oil spill treatment has been addressed using nanocomposite-based natural fibers. These materials offer great potential in oil spill cleanup and are considered due to their environmental friendliness, high efficiency, and low cost. Thus, the current study reports a novel composite fabricated from date palm fiber (DPF) and recycled polyethylene terephthalate (rPET) with a proper combination of a mixture of carbon nanotubes (CNTs) and graphene nanosheets (GNSs) for oil removal. The established nanocomposite (DPF-rPET/CNT/GNS) was fabricated via physical mixing of various quantities (0.9, 0.8, and 0.7 g) of PET, along with varying loads of DPF at different proportions of CNT:GNS. The prepared nanocomposite (DPF-rPET/CNT/GNS) was fully characterized using scanning electron microscopy–energy dispersive X-ray (SEM-EDX) analysis, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), and Brunauer–Emmett–Teller (BET) analysis. In static experiments and under the optimal parameters of pH, sorbent doze, shaking time, and quantity of diesel oil), the established sorbent (DPF-rPET/CNT-GNS nanocomposite) displayed excellent adsorption capacity (98 mg/g). This study also expands the utility of the sorbent for the reusability of the oil adsorption, maintaining performance after five cycles. The adsorption data fitted well with the Langmuir isotherm model with a correlation coefficient (R2) of 0.99 and maximum adsorption capacity of 99.7 mg/g, indicating monolayer adsorption. Additionally, the adsorption kinetics followed a pseudo-second-order model, with an R2 near unity and an adsorption capacity of 99.09 mg/g. This study highlights the promising potential of the DPF-rPET/CNT-GNS composite as an effective adsorbent for treating oily water.

Tailored nanofibrous polyimide-based membranes for highly effective oil spill cleanup in marine ecosystems

Oil spills pose significant environmental threats to marine ecosystems and indirectly affect human health. They are often caused by tanker accidents and pipeline leaks. The persistence of hydrocarbons in the marine environment and their long-term ecological impacts necessitate efficient remediation strategies. Nanofibrous membranes made from polyimides with varying hydrophobicity present a promising solution for oil spill cleanup and oil/water separation. In this study, electrospun nanofibrous membranes were fabricated using 4,4′-(hexafluoroisopropylidene)diphthalic anhydride (6FDA) combined with 3,5-diamino-2,4,6-trimethylbenzenesulfonic acid (TrMSA) and 2,3,5,6- tetramethyl-p-phenylenediamine (TMPD) to produce bead-free nanofibers at optimized concentrations. These membranes exhibited hydrophobic characteristics and high oil absorption capabilities. The 6FDA-TMPD membrane achieved a maximum adsorption capacity of 76.50 ± 7.32 g g−1 for Varinca crude oil, while the 6FDA-TrMSA membrane reached 80.05 ± 6.60 g g−1. In comparison, the commercial 3M™ oil sorbent had a significantly lower capacity of 29.4 ± 3.8 g g−1 for the same oil. The nanofibrous membranes also demonstrated superior performance in adsorbing gasoline and diesel and maintained their effectiveness across multiple cycles, highlighting their potential to mitigate the environmental impact of oil spills.

Facile fabrication of green and sustainable gelatin-based aerogels for marine oil spill recovery

Efficient and rapid cleanup of marine oil spills is crucial for environmental protection and resource recovery. Biomass aerogel has a broad application prospect in oil spill treatment, but is often limited by the complex preparation process and the use of toxic cross-linking agents. In this study, the hydrophobic gelatin-based aerogels (HGAs) were simply prepared for marine oil spill recovery based on self-crosslinking of gelatin, bubbles produced by surfactants and high-speed stirring, and chemical vapor deposition using methyl trichlorosilane (MTCS). The results showed that the HGAs exhibited a three-dimensional porous structure with a water contact angle of 131.6°. Their adsorption capacities for various oils and organic solvents ranged from 60.4 to 146.5 g/g, which was linearly related to the oil density and depended on the number of pores within the material. The oil adsorption by the HGAs reached equilibrium within 30 s, following the pseudo-second-order kinetic model and the HGAs were highly stable in different temperature, pH, and salinity conditions. Simple squeezing can recover 80 % of the spilled oil, and retain 86 % of the initial adsorption capacity after 10 adsorption-squeeze cycles. Additionally, the HGAs had an excellent continuous oil-water separation performance, demonstrating significant potential and practicability in marine oil spill recovery.

Magnetically separable sorbent based on activated carbon derived from a new precursor Rhizoclonium hookeri for facile oil spill clean-up

A huge quantity of synthetic toxic materials ends-up in water bodies causing long-lasting environmental and economic impacts due to catastrophic oil spill. Exploring marine algae as sorbent materials for oil spill remediation is a relatively new area and holds great potential. Herein, macroalgae Rhizoclonium hookeri (RH) derived magnetically recoverable activated carbon (RHAC@Fe3O4) composite has been proposed as an innovative and robust strategy for oil spill clean-up. The oil uptake efficiency of RHAC@Fe3O4 was probed using unused and used motor oil in synthetic seawater matrices by conducting batch wise experiments. Optimal conditions for the designed sorption system were met by varying time (10–60 min), dosage (0.2–1 g) and temperature (20, 30, 40 °C). Characterization studies showed that KOH-based activation played a vital role in developing pore structure and surface functionalities in the algal biochar. Batch experiments demonstrated over 90 % oil removal efficiency of RHAC@Fe3O4 from simulated oil spill after 30 min using 0.8 g of composite. Moreover, Fe3O4 loading onto carbon material allowed magnetic separation as a convenient alternative to filtration for the recovery of oil laden composite. Apart from superior oil removal ability, synthesized composite demonstrated robust performance up to five cycles in synthetic sea water matrices. Additionally, comparative study revealed better oil sequestration efficiency of the fabricated RHAC@Fe3O4 composite (93 %) as compared to its precursors, i.e. algal biochar (71 %) and AC (88 %). Based on these findings, it is advocated that designed RHAC@Fe3O4 composite being eco-friendly, economical and readily recoverable with enhanced oil uptake ability could potentially be an innovative platform for oil spill clean-up applications.

Synthesis of magnetic polystyrene nanocomposite by emulsion polymerization using a photo-responsive emulsifier for efficient crude oil absorption

Both human health and marine life are seriously threatened by crude oil spills into bodies of water. For effective crude oil spill cleaning, we created a magnetic polystyrene (m-PS) nanocomposite. The use of magnetic nanoparticles makes crude oil absorption more environmentally friendly by making it easier to collect and recycle using an external magnetic field. To make Fe3O4 nanoparticles compatible with the hydrophobic styrene monomer used in emulsion polymerization, they were treated using a hydrophobic surface modification reaction. This alteration facilitated the grafting of polystyrene (PS) chains onto the nanoparticles, which then underwent emulsion polymerization. As an emulsifier, a light-responsive amphiphilic block copolymer containing coumarin was created via reversible addition-fragmentation chain transfer polymerization. This allowed for regulated emulsification and demulsification in response to UV stimulation. The synthesized m-PS nanocomposite demonstrated a crude oil absorption capacity of up to 2.31 times of its own weight, indicating its high efficiency for crude oil spill cleanup. The synthetic emulsifier exhibited a significantly lower critical micelle concentration compared to the commercial P105 emulsifier (0.0976 against 0.354 mg/mL, respectively), indicating higher efficiency and reduced environmental impact. For a more thorough comprehension of the reported results, we also assessed the Hofmeister effect in PS produced using commercial and synthetic emulsifiers.

Synthesis And Efficiency Evaluation of Chitosan-Alginate Hydrogel Polyelectrolyte Complex Filter for Treatment of Oil Spillage

Crude oil spills pose considerable environmental concerns thereby demanding the development of effective, sustainable, and eco-friendly remediation solutions. In this study, we synthesized and evaluated the efficiency of a biodegradable polymer filter using sodium alginate and chitosan for the treatment of oil spillage. The sodium alginate-chitosan hydrogel polyelectrolyte complex (SACHPC) filter was synthesized via dipping method using a layer-by-layer self-assembly technique integrated with cotton wool as the filter medium. The efficiency of the filter was evaluated based on flow rate of recovered oil and reusability of the filter. Simulated oil spillage of 0.5 M was subjected to filtration using the SACHPC filter. The flow rate was determined based on the time taken for 1 L of oil to pass through the filter. The SACHPC filter exhibited underwater superoleophobic behaviour with exceptional filtration efficiency (> 98.3%) in acidic, neutral and alkaline conditions (pH 3, 7 and 11). The flow rate of the filter was 120 mL/min, while the third-use filter exhibited a decrease flow rate of 50 ml/min. Moreover, the filter achieved an impressive crude oil recovery rate of 85%. X-ray diffraction analysis confirmed crude oil adsorption in the presence of an amorphous phase while scanning electron microscopy analysis revealed the structural morphology of the SACPHC filter. Overall, the SACHPC filter maintained high filtration efficiency thereby offering a sustainable strategy for oily wastewater purification and oil spill clean-up.

Enhanced Hydrophobicity and Oleophilicity of Modified Activated Carbons Derived from Agro-Wastes Biomass for the Removal of Crude Oil from Aqueous Medium

Crude oil spillage has tremendous environmental impacts and poses severe pollution problems worldwide due to the continuous activities and operations in the oil and gas sector. This has resulted in the urgent need for clean-up techniques such as the use of natural adsorbents which is considered a relatively low-cost, readily-available, efficient, eco-friendly, and easy-to-deploy mode of addressing oil spillage due to its high oil sorption capacity/efficiency, high oil selectivity, oleophilic, enduring, reusability and biodegradable properties. Empty palm fruit bunch and coconut coir were used as precursors to produce activated carbons for oil spill remediation. The influence of varying parameters was investigated using a batch experimental procedure resulting in the crude oil adsorption capacity increasing with a corresponding increase in contact time, initial oil concentration, temperature, agitation speed, and particle size but decreasing in adsorbent dosage. The combination of surface morphological modification and hydrophobicity enhancement resulted in significantly improved adsorption capacity for crude oil removal (2710.0 mg/g and 4859.5 mg/g for EPFBAC<SUB>LA</SUB> and CCAC<SUB>L.A</SUB> respectively), as evidenced by both FTIR and SEM analyses. The experimental isotherm data were analysed using various isotherm models and the best-fitted isotherm model was the Freundlich model with a correlation coefficient (R<sup>2 </sup>= 0.991 and R<sup>2 </sup>= 0.999) for EPFB<SUB>L.A</SUB> and CCAC<SUB>L.A</SUB> respectively. The kinetic behaviour of the adsorption process was best described by pseudo-second order with R<sup>2</sup> values of 0.970 and 0.999 for EPFBAC<SUB>LA</SUB> and CCAC<SUB>L.A</SUB> respectively while Boyd model revealed that the adsorption was controlled by an internal transport mechanism and film diffusion was the rate-limiting step. The crude oil adsorption was chemisorption and endothermic owing to the positive enthalpy values (ΔH<sup>o</sup> = 183.890 KJ/mol for EPFBAC<SUB>L.A </SUB>and ΔH<sup>o</sup> = 69.656 KJ/mol for CCAC<SUB>L.A</SUB>), the positive value of entropy suggested that the adsorption process was accompanied by an increase in the degree of randomness or disorder at the interface between the adsorbent and the adsorbate. A temperature rise led to a decline in Gibbs energy (ΔG<sup>o</sup>), suggesting that adsorption became more feasible and spontaneous at higher temperatures and the significant activation energies indicated the existence of a substantial energy barrier that must be overcome to initiate the reaction. The results showed the significant capability of the prepared adsorbents to be used as a low-cost, re-generable and eco-friendly adsorbent in oil spill clean-up and is recommended to exploit its usage on a large scale.