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Petroleum hydrocarbon (PH) pollution threatens both wild and farmed marine fish. How this pollution affects the nutrient metabolism in fish and whether this effect can be recovered have not been well-known. The present study aimed to evaluate these effects with a feeding trial on tiger puffer, an important farmed species in Asia. In a 6-week feeding trial conducted in indoor flow-through water, fish were fed a control diet (C) or diets supplemented with diesel oil (0.02 % and 0.2 % of dry matter, named LD and HD, respectively). Following this feeding trial was a 4-week recovery period, during which all fish were fed a same normal commercial feed. At the end of the 6-week feeding trial, dietary PH significantly decreased the fish growth and lipid content. The PH significantly accumulated in fish tissues, in particular the liver, and caused damages in all tissues examined in terms of histology, anti-oxidation status, and serum biochemical changes. Dietary PH also changed the volatile flavor compound profile in the muscle. The hepatic transcriptome assay showed that the HD diet tended to inhibit the DNA replication, cell cycle and lipid synthesis, but to stimulate the transcription of genes related to liver protection/repair and lipid catabolism. The 4-week recovery period to some extent mitigated the damage caused by PH. After the recovery period, the inter-group differences in some parameters disappeared. However, the differences in lipid content, anti-oxidase activity, liver PH concentration, and histological structure still existed. In addition, differences in cellular chemical homeostasis and cytokine-cytokine receptor interaction at the transcriptional level can still be observed, indicated by the hepatic transcriptome assay. In conclusion, 6 weeks of dietary PH exposure significantly impaired the growth performance and health status of farmed tiger puffer, and a short-term recovery period (4 weeks) was not sufficient to completely mitigate this impairment., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The treatment of oily sludge (OS) can not only effectively solve environmental pollution but also contribute to the efficient use of energy. In this study, the separation effect of OS was analyzed through sodium lignosulfonate (SL)-assisted sodium persulfate (S/D) treatment. The effects of SL concentration, pH, temperature, solid-liquid ratio, revolving speed, and time on SL adsorption solubilization were analyzed. The effects of sodium persulfate dosage, demulsification temperature, and demulsification time on sodium persulfate oxidative demulsification were analyzed. The oil removal efficiency was as high as 91.28%. The results showed that the sediment was uniformly and finely distributed in the S/D-treated OS. The contact angle of the sediment surface was 40°, and the initial apparent viscosity of the OS was 56 Pa·s. First, the saturated hydrocarbons and aromatic hydrocarbons on the sediment surface were adsorbed by the monolayer adsorption on SL. Stubborn, cohesive oil agglomerates were dissociated. Sulfate radical anion (SO 4 - · and polycyclic aromatic hydrocarbons. A good three-phase separation effect was attained. The oil recovery reached 89.65%. This provides theoretical support for the efficient clean separation of oily sludge.4 - · and polycyclic aromatic hydrocarbons. A good three-phase separation effect was attained. The oil recovery reached 89.65%. This provides theoretical support for the efficient clean separation of oily sludge.

The 2007 Hebei Spirit oil spill (HSOS), the largest in the national history, has negatively impacted the entire environment and ecosystem along the west coast of South Korea. Although many studies have reported the damages and impacts from the HSOS, quantitative assessment evaluating the recovery time and status have not been documented. Here, we first address the recovery timeline of the HSOS, by comprehensive analyses of 10-years accumulated data in quantitative manner. Concentrations of residual oils in seawater, sediments, and oysters rapidly dropped to backgrounds in 16, 75, and 33 months, respectively. Also, damaged benthic communities of intertidal and subtidal areas were fully recovered only after ~6 years. The present results collectively indicated unexpectedly fast recovery of the damaged environment and ecosystem from such a huge oil spill. The high tidal mixing (~9 m tidal height) and intensive human cleanup (~1.2 million volunteers) at the initial cleanup period might have contributed to rapid recovery; cf. 4-5 times faster than the Exxon Valdez oil spill. However, potential risk to human health remains unclear. Thus, it is warranted to conduct more in depth epidemiological studies to address chronic health effects associated with the cleanup volunteers as well as the local residents who have been living nearby the oil spill impacted sites., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Industrial activities and urbanization are the main sources of pollutants in estuarine environments. Diesel, which is widely used in urban and port activities, is an important source of hydrocarbons in the aquatic environment, and its water-accommodated fraction (WAF) is toxic to the local biota. This study was performed to analyze the effects of diesel oil WAF on fish. Specifically, we characterized the gill morphology of the seahorse Hippocampus reidi and analyzed the histopathological changes in the gills after exposure to 50% diesel oil WAF. Acute (12, 24, 48, and 96 h) and subchronic (168 and 336 h) toxicity tests were performed. Furthermore, a recovery protocol was conducted: after exposure to 50% WAF for 168 h, the fish were transferred and kept in seawater without contaminants for 336 h, for a total experimental period of 504 h. The seahorse branchial apparatus was found to be tufted with short filaments; the apical surfaces of the pavement cells in the filament and lamellar epithelia formed "crests" and had microridges. Mitochondria-rich cells were distributed exclusively in the lamellar epithelium, while mucous cells were distributed in the filament epithelium. All pathologies observed after acute and subchronic exposure featured progressive time-dependent alterations of lamellar structure that might disrupt gill physiological and metabolic functions. During the recovery period, the gill alterations were gradually repaired., (Copyright © 2019. Published by Elsevier Ltd.)

Acute exposure to crude oil polycyclic aromatic hydrocarbons (PAH) can severely impair cardiorespiratory function and swim performance of larval fish; however, the effects of acute oil exposure on later life stages and the capacity for subsequent recovery is less clear. Red drum (Sciaenops ocellatus) is an economically important apex predator native to the Gulf of Mexico, which was directly exposed to the 2010 Deep Water Horizon (DWH) oil spill. Here we examine impact and recovery of young adult red drum from exposure to concentrations of 0, 4.1, and 12.1μgL -1 ΣPAH 50 naturally weathered oil-water accommodated fractions (geometric mean), which are well within the range of concentrations measured during the DWH incident. We focused on aerobic scope (ASc), burst- and critical swimming speeds (U burst and U crit ), cost of transport (COT), as well as the capacity to repay oxygen debt following exhaustive exercise (EPOC), which are critical parameters for success of all life stages of fishes. A 24h acute exposure to 4.1μgL -1 ΣPAH caused a significant 9.7 and 12.6% reduction of U burst and U crit respectively, but no change in ASc, COT or EPOC, highlighting a decoupled effect on the respiratory and swimming systems. A higher exposure concentration, 12.1μgL -1 ΣPAH, caused an 8.6 and 8.4% impairment of U burst and U crit , as well as an 18.4% reduction in ASc. These impairments persisted six weeks post-exposure, suggesting that recorded impacts are entrenched. Large predatory fishes are critically dependent on the cardiorespiratory and swimming systems for ecological fitness, and long-term impairment of performance due to acute oil exposure suggests that even acute exposure events may have long lasting impacts on the ecological fitness of affected populations., (Copyright © 2017. Published by Elsevier B.V.)

We measured the concentration of petroleum hydrocarbons in 405 wetland sediment samples immediately before the April 2010 Deepwater Horizon disaster led to their broad-scale oiling, and on nine trips afterwards. The average concentrations of alkanes and PAHs were 604 and 186 times the pre-spill baseline values, respectively. Oil was distributed with some attenuation up to 100m inland from the shoreline for alkanes, but increased for aromatics, and was not well-circumscribed by the rapid shoreline assessments (a.k.a. SCAT) of relative oiling. The concentrations of target alkanes and PAHs in June 2013 were about 1% and 5%, respectively, of the February 2011 concentrations, but remained at 3.7 and 33 times higher, respectively, than in May 2010. A recovery to baseline conditions suggests that the concentration of alkanes may be near baseline values by the end of 2015, but that it may take decades for the PAH concentrations to be that low., (Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.)

In a review of the literature on impacts of spilled oil on marshes, 32 oil spills and field experiments were identified with sufficient data to generate recovery curves and identify influencing factors controlling the rate of recovery. For many spills, recovery occurred within 1-2 growing seasons, even in the absence of any treatment. Recovery was longest for spills with the following conditions: Cold climate; sheltered settings; thick oil on the marsh surface; light refined products with heavy loading; oils that formed persistent thick residues; and intensive treatment. Recovery was shortest for spills with the following conditions: Warm climate; light to heavy oiling of the vegetation only; medium crude oils; and less-intensive treatment. Recommendations are made for treatment based on the following oiling conditions: Free-floating oil on the water in the marsh; thicker oil (>0.5 cm) on marsh surface; thinner oil (<0.5 cm) on marsh surface; heavy oil loading on vegetation; and light to moderate oil loading on vegetation., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Preliminary impact assessment of two large oil spill incidents at Bodo Creek, in the Niger Delta, was undertaken, focusing on intertidal macrozoobenthos. Post-spill number of species and abundance were measured against recent pre-spill baseline data from the same study area. Results show that surface and infauna communities suffered severe reduction in abundance and number of species reduced by 81% after the spills, with two of the resampled sites having no taxa at all. Capitella capitata populations increased several-fold over pre-spill numbers. The impact of the oil spills is discussed in relation to local livelihoods and ecosystem integrity. The Niger Delta endemic lucinid, Keletistes rhizoecus, is proposed as a potential bioindicator for monitoring hydrocarbon contamination in Niger Delta estuaries., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

In order to improve the efficiency of crude oil recovery, reduce the adhesion and adsorption of crude oil in the formation, reduce the interfacial tension of oil and water to form a stable emulsion, the performance evaluation of new surfactants and methods for improving oil recovery are studied. The esterification reaction is used to synthesize the raw material of glyceryl monooleate succinic acid monoester, and the raw material is neutralized with an alkaline solution to prepare a new surfactant. Through experiments, the surfactant's interfacial tension, salt resistance, temperature resistance, emulsification, viscosity reduction and other properties were evaluated, and the effect of changing the oil recovery rate after using the surfactant was studied. Test results show that this new surfactant can significantly reduce the water-oil interfacial tension, and can still reduce the water-oil interfacial tension even in saline environments and high temperature environments. After the temperature reaches 50°C, the temperature resistance is basically stable; When the surfactant concentration of the water-oil ratio is lower than 7:3 and higher than 700mk/L, it can reduce the viscosity of the water-oil mixture; the surfactant has good foam performance and emulsification, and can effectively improve crude oil recovery. Use 0.25% mass fraction surfactant, can effectively improve oil recovery, but abnormal low-pressure environment will affect the recovery effect. [ABSTRACT FROM AUTHOR]

As an important unconventional oil and gas resource, tight oil reservoirs are difficult to achieve ideal recovery rates with conventional oil recovery methods. In this paper, the oil driving effect of different gases (CO2 and N2) in tight reservoirs was investigated, and the auxiliary roles of chemicals such as surfactants and polymers in the gas driving process were also discussed. An autoclave was used for the different gas drive experiments, with a set pressure range of 10 MPa to 30 MPa, a constant temperature of 60°C, and the gas injection rate was adjusted to evaluate the drive effect. In addition, the effects of surfactants SDBS and C12-14 Pareth-7, as well as polymers PAM and HPAM at different concentrations on the gas drive effect were investigated. The results showed that the oil driving effect of CO2 was better than that of N2, and the oil recovery of CO2 drive was increased by more than 20% at 30 MPa and 20 mL/min. With the addition of surfactant, SDBS increased the recovery by 15% at 0.3% concentration, while PAM increased the recovery by 10% at 0.4% concentration. This study demonstrated the superiority of CO2 gas drive in tight reservoirs and elucidated the enhancement effect of chemical adjuvants in the gas drive process by analyzing detailed experimental data. These findings provide an important theoretical basis and technical support for optimizing the gas-drive development scheme in tight reservoirs, which improves the crude oil recovery and has important practical application value. [ABSTRACT FROM AUTHOR]

Crude palm oil (CPO) is highly abundant in carotenoids. Previous findings found that dry fractionation can concentrate carotenoids from CPO but resulted in a significant loss of carotenoids. Therefore, the present study aimed to utilize solvent fractionation, which offers a better separation efficiency, to concentrate carotenoids from CPO with improved recovery. Computational study revealed a high binding affinity of phytonutrient towards unsaturated triacylglycerols (TAGs) species in olein fraction due to similar polarity. This prediction was further verified with evidence showing strong, positive correlation between the iodine value and carotenoids concentrations of fractionated oil. The difference in binding affinity of saturated and unsaturated TAG towards different solvents can be used as a guide for screening and selection of solvent suitable for recovery of phytonutrient during solvent fractionation. Subsequently, a lab‐scale single‐ stage fractionation study disclosed that crystallization temperature of 15°C, oil to acetone ratio of 1:5 (w/v) for 4 h under agitation at 100 rpm produced olein with the highest carotenoid concentration (637 ppm) and recovery (94%). Subsequent double‐stage fractionation successfully concentrated the carotenoids up to 125% with a recovery of >93%. Conclusively, solvent fractionation provides an effective way to concentrate valuable carotenoids from CPO while minimizing the lost. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to comprehensively comprehend the distinctions in solution properties, emulsification characteristics, and oil displacement efficiency between polymeric surfactant(DG-1) and traditional polymers or surfactants, a comparative analysis was initially conducted on the microstructure, main functional group types, and macroscopic properties. Subsequently, core displacement experiments were employed to elucidate the emulsification capability, emulsion stability, and oil displacement properties of polymeric surfactants. The microscopic displacement experiment was ultimately conducted to investigate the residual oil displacement process in the core following polymer displacement by DG-1, thereby elucidating the underlying mechanisms of microscopic oil displacement by DG-1. The results indicate DG-1 has a molecular structure with a regional network aggregation state as a whole, and a multi-layer aggregation and overlapping structure in space. DG-1exhibits higher viscosity and lower interfacial tension due to the larger molecular coil dimension compared to the equivalent concentration of polymers. The emulsification ability of DG-1 is robust, with emulsion stability positively correlated to oil-polymer ratio and concentration while negatively correlated to migration distance. Core displacement experiments results indicate the polymer-surfactant system (SP) and DG-1 exhibited comparable oil displacement effects, with oil recovery of 54.5 % and 52.4 %, respectively, both surpassing the recovery achieved by the polymer alone (46.9 %). In heterogeneous reservoirs, SP acts as the dominant displacer in regions with moderate and high permeability, whereas DG-1 assumes dominance in regions with moderate and low permeability. The microscopic displacement experiments revealed that DG-1 activated the clustered residual oil as the predominant type of residual oil in porous media, followed by columnar and block residual oil, with film residual oil exhibiting the least activation. Primary mechanisms for oil displacement include extended sweeping volume, shear and carrying effects on the residual oil, and eddy displacement of the residual oil by the emulsion. [Display omitted] [ABSTRACT FROM AUTHOR]

During the study of Sinian-Cambrian system gas reservoirs in the middle paleo-uplift of Sichuan Basin, some wells of Longwangmiao formation in Moxi area had yellow fluorescent organic matter in thin sections under core-mirror was found. Based on the core observation and dissolution experiments, the characteristics of the biomarkers of saturated hydrocarbons under different conditions were determined by saturated hydrocarbon chromatography-mass spectrometry. The results show that the organic matter observed in the thin section under core-mirror is not the crude oil formed by multi-period accumulation, but polluted by oily substances in the drilling fluid during the drilling process. The presence of pollutants will affect the recovery of crude oil. Therefore, this study uses geochemical methods to identify the pollutants in the core and improve the recovery of crude oil. [ABSTRACT FROM AUTHOR]

Emulsion separated by a disk stack centrifugal separator is the leftover from salmon skin hydrolyzed collagen production, in which oil can be recovered for further uses. Impacts of ammonium sulfate (AS) at different levels (0–10%, w/w) and freeze‐thawing with various cycles (0–7) on destabilization of emulsion separated from salmon skin (Oncorhynchus nerka) hydrolysate and quality of recovered oil are investigated. Emulsion added with AS shows larger oil droplet size (p < 0.05) with lower negative charge (p< 0.05). Oil yield and recovery are increased (p < 0.05) with augmenting concentrations of AS and freeze–thawing cycles. Highest yield (4.01%) and recovery (87.36%) (p < 0.05) are obtained for oil recovered from emulsion added with 10% AS in conjunction with freeze–thawing for three cycles. Oils recovered from emulsion added with AS (0–10%) and freeze–thawed for 0 and 3 cycles show no differences in hydrolysis, oxidation, and astaxanthin content (5.19–5.62 mg kg−1 oil). Furthermore, no marked differences in fatty acid composition and FTIR spectra are observed. Therefore, the use of 10% AS in conjunction with freeze–thawing (3 cycles) is a promising means for recovery of oil from emulsion, which can be an alternative source of nutraceutical. Practical applications: Oil–water emulsion is a by‐product separated from production of salmon skin hydrolysate with the aid of a disk stack centrifugal separator (DSCS). Retained peptides could act as emulsifier and stabilize oil droplets in emulsion. To recover oil from emulsion, the destabilization of emulsion is required. Addition of ammonium sulfate (AS) can destabilize emulsion via peptides precipitation, thus liberating the oil. Moreover, the repeated freeze–thawing in combination with AS under optimal condition is shown to enhance oil yield and recovery. Therefore, oil rich in astaxanthin and polyunsaturated fatty acid from the discarded emulsion can be recovered and further exploited. [ABSTRACT FROM AUTHOR]

Chitosan/zeolite-X (CHS/ZX) was synthesized to serve as an effective adsorbent for metal porphyrins through adsorption processes as an alternative to traditional separation methods from crude oil. The adsorption-desorption mechanisms of vanadyl and nickel tetraphenyl porphyrin (VO-TPP and Ni-TPP) were conducted on the model solution. Compared to individual components CHS and ZX, the CHS/ZX composite exhibited a doubled capacity for metal porphyrin removal. The synthesized composite was systematically characterized using FESEM, BET, XRD, FTIR, TGA, XPS, and CHN analyses. The study investigated the impact of many factors, including temperature, initial metal-porphyrin concentration, CHS/ZX dose, and contact time, on the adsorption efficiency of metal-porphyrin using CHS/ZX adsorbents. The adsorption processes of VO-TPP and Ni-TPP on CHS/ZX were effectively assessed through various equilibrium models, such as Langmuir, Freundlich, and Dubinin-Radushkevich (D-R). The pseudo-second-order model accurately depicted the adsorption processes of both VO-TPP and Ni-TPP. Determining the point of zero charge (pH PZC) highlighted the composite's surface charge distribution. Furthermore, considering the ΔG° and ΔH° values, the adsorption processes at different temperatures are exothermic, and VO-TPP exhibits a greater adsorption capacity than Ni-TPP under similar conditions. Notably, 73.7 % of VO-TPP and 83.8 % of Ni-TPP that were adsorbed were successfully recovered. [ABSTRACT FROM AUTHOR]

To overcome the disadvantages of severe emulsification and difficulty in obtaining free oil during aqueous extraction of peanut oil, the effect of roasting assisted aqueous ethanol extraction on free oil recovery was investigated. When peanut kernels were roasted at 180 °C for 10 min, free oil recovery increased from 57% to 96%, and the acid and peroxide values of the peanut oil met the requirements of good quality. The degree of hydration swelling of proteins in the extract increased, and soluble solids were easier to aggregate, resulting in reduced emulsification and significantly higher free oil recovery. The roasting conditions selected were found to significantly promote protein hydrophilicity, aggregation and fusion of oil bodies, as well as cell rupture, which facilitated the release of free oil but with a lower degree of protein denaturation. This study may promote the practical application of aqueous extraction technology for peanut oil. [Display omitted] • Free oil recovery of peanut oil exceeded 95% without demulsification. • Peanut proteins were more hydrophilic but were less denatured. • Roasting caused separated oil bodies to aggregate and fuse, as well as cell rupture. • Roasting reduced emulsification but had no effect on oil quality. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this review, we focus on engineered nanomaterials (NMs) offering economic and environmental sustainability in oil extraction. We introduce underlying issues in oil recovery and separation and discuss fundamental physical and chemical interactions in typical oil‐water‐solid systems that guide the design of NMs. In recovery, the NMs change rock wettability, permeability, or sweep fluid properties to attain optimal resource use and minimal environmental impact. Applied NMs include nanosurfactants, silica core‐shell structures, nano‐encapsulated acids, and nanofluids. While for separation, the NMs use mechanisms of adsorption, filtration, or dispersion to improve separation performance in industrial or aquatic oil spill settings. The NMs include iron oxide nanoparticles, graphene Joule‐heating sponges, superhydrophilic poly(vinylidene fluoride) membranes, and amphiphilic Janus silicon dioxide nanoparticles. Albeit the NMs exhibit impressive performance in sustainable oil extraction, a technological gap remains between the lab‐scale demonstrations and practical field deployment. We conclude with a perspective on bridging this gap. [ABSTRACT FROM AUTHOR]

Miscible CO2-based enhanced oil recovery (CO2-EOR) flooding has been used, on many occasions, to maximize the recovery by mobilizing the residual oil. The success of this method, however, depends highly on the minimum miscibility pressure (MMP), the compatibility of CO2 with the reservoir rock and fluids. Although there have been several studies on the application of CO2-EOR, the impact of oil compositions associated with MMP on the feasibility of this technique has not been addressed elsewhere. In this study, a simulation study was carried out to investigate the effect of three different oil compositions on the miscibility and ultimate oil recovery of miscible CO2-EOR method. The results obtained indicated the oil type does not pose a significant impact on the success of miscible CO2-EOR. It was also found that the ultimate recovery of oil increases in a short period of time by injecting CO2 at the miscible conditions at the early stage of natural production. Comparatively, the reservoir with the fluid sample S2 seems to be a suitable choice for the miscible CO2 flooding once the recovery factor was considered together with the total amount of the fluid injected and produced. [ABSTRACT FROM AUTHOR]

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The presence of an alkali such as sodium hydroxide (NaOH) within a process of enhanced recovery of crude oil having certain acidity allows the formation of surfactants with the ability of enhancing the separation of the crude oil from the reservoir rock where it is adsorbed due to a change of wettability. This work focused on studying the effect of NaOH on the enhanced recovery, in terms of the SARA composition, of two different API gravity crude oils (38.5 and 24.1°) having different total acid number. The results showed the existence of acid components with high and low reactivity to NaOH in the crude oil, where the first group is responsible of the in-situ synthesis of the surfactant. Moreover, it was found that the utilization of the alkali improved the recovery of the SARA fractions for each crude oil, especially for the 24.1°API crude oil for which the recovery resulted twice or three times higher to the evaluated for the 38.5°API crude oil. Additionally, it was found that a minimum of 0.2 wt% of NaOH reduced up to 4 times the value of the interfacial tension between the crude oil and the brine, regardless of the type of crude oil. [ABSTRACT FROM AUTHOR]

Global demand for petroleum keeps increasing while traditional supplies decline. One alternative to the use of conventional crude oils is the utilization of Canadian bitumen. Raw bitumen is a dense, viscous, semi-liquid that is diluted with lighter crude oil to permit its transport through pipelines to terminals where it can then be shipped to global markets. When spilled, it naturally weathers to its original form and becomes dense enough to sink in aquatic systems. This severely limits oil spill recovery and remediation options. Here we report on the application of charred hay as a method for modifying the surface behavior of bitumen in aquatic environments. Waste or surplus hay is abundant in North America. Its surface can easily be modified through charring and/or chemical treatment. We have characterized the modified and charred hay using solid-state NMR, contact angle measurements and infrared spectroscopy. Tests of these materials to treat spilled bitumen in model aquatic systems have been undertaken. Our results indicate that bitumen spills on water will retain their buoyancy for longer periods after treatment with charred hay, or charred hay coated with calcium oxide, improving recovery options.