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Hydrocarbons in seawater

necessitating careful disposal. During the Deepwater make other recovery methods difficult. However, in situ
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Horizon oil spill (2010), thousands of miles of booms burning causes air pollution, including the production
were deployed to protect the intricate marshlands and of particulate matter, volatile organic compounds, and
coastlines of the Gulf of Mexico. While effective in other combustion byproducts, raising concerns about air
localized, calmer areas, their overall impact was limited quality and potential health impacts. Public perception
by the sheer scale of the offshore spill and prevailing is not usually positive due to visible smoke plumes and
weather conditions. 28,46 the generation of atmospheric pollution. In situ burning
In recent years, innovative technologies have been was a key component of the Deepwater Horizon oil spill
developed to remediate hydrocarbon contamination in response. Over 400 controlled burns were conducted,
the marine environment. Among these, nanomaterials removing an estimated amount of approximately 35,000
offer a promising solution for crude oil absorption tons of crude oil, demonstrating its capacity for rapid oil
from the sea. Their exceptionally high surface area-to- removal in large-scale offshore incidents, when the vast
volume ratio enables efficient capture of oil molecules. extent of the contamination and adverse environmental
Materials, such as graphene, carbon nanotubes, and conditions do not allow the adoption of different
various metal-organic frameworks can be engineered techniques. 28,46
to be superhydrophobic and oleophilic, meaning they Another debated and controversial practice is the use
repel water while attracting oil. When deployed, these of substances called dispersants. These are chemical
nanomaterials can rapidly absorb significant quantities agents sprayed onto oil slicks to break the oil into tiny
of spilled oil, forming stable aggregates that are easier droplets, allowing it to mix with the water column. This
to recover from the water surface. This aids in rapid process facilitates dilution and degradation through
cleanup and minimizes the environmental impact by natural processes and prevents the oil from rapidly
preventing the spread and long-term consequences of spreading. Dispersants can quickly break up large,
oil contamination on marine ecosystems. 102 widespread slicks, preventing them from impacting
Once contained, or when containment is challenging, coastlines, wetlands, and surface-dwelling wildlife.
various techniques are employed to remove or disperse They can be applied efficiently from aircraft or vessels,
the oil. Skimming involves using specialized vessels rapidly responding to large-scale spills. The increased
or skimmers to physically remove oil from the water surface area of dispersed oil can accelerate natural
surface. Skimmers operate through various principles, biodegradation by marine microbial communities.
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including weir skimmers, which allow oil to flow over a However, the use of these substances is not without
weir into a collection tank, oleophilic skimmers, where risks. A primary concern is the potential toxicity to
oil adheres to a rotating surface and is then scraped off, marine life from the dispersant chemicals and dispersed
and vacuum skimmers. Skimming usually consists oil, which can become more bioavailable to organisms
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of directly recovering the oil, making it available for in the water column. Dispersants do not remove oil
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potential recycling or proper disposal, thus reducing the from the environment; they merely change its physical
total volume of contaminants in the environment. It is state and location, often driving it deeper into the
most effective in calm waters with relatively thick oil. water column. Their effectiveness varies with oil type,
The efficiency of such a technique may be compromised water temperature, and salinity. The large-scale use of
in rough seas, as wave action can break up the slick and dispersants, particularly subsea applications, has been
mix the oil with the water column. Debris mixed with highly controversial. 48,103
the oil can clog skimmer mechanisms, and the process Chemical dispersants are complex mixtures, typically
often collects significant volumes of water along with composed of surfactants and solvents. Surfactants
the oil, requiring further separation. 47 are the key molecules that reduce the interfacial
A controversial containment method is represented tension between oil and water, facilitating droplet
by in situ burning, which involves the controlled ignition formation. Surfactants are amphiphilic molecules
and burning of oil on the water surface. It is often used with both oleophilic and hydrophilic components.
with fire-resistant booms to concentrate the oil into a This duality allows them to position themselves at
thick layer before ignition. This approach offers a rapid the oil-water interface, lowering the surface tension
way to remove large quantities of oil, significantly and fragmenting the oil into small droplets. The most
reducing the volume that needs to be physically common surfactants are sorbitan esters (e.g., sorbitan
recovered and disposed of. It can be particularly monooleate), a non-ionic substance derived from
effective in remote areas where logistical challenges sugars, often used for their emulsifying properties

Volume 22 Issue 6 (2025) 37 doi: 10.36922/AJWEP025290224