Oil Spill Dispersants Research Articles

An effective dispersant for oil spills based on food-grade amphiphiles.

Synthetic dispersants such as Corexit 9500A were used in large quantities (∼2 million gallons) to disperse the oil spilled in the ocean during the recent Deepwater Horizon event. These dispersant formulations contain a blend of surfactants in a base of organic solvent. Some concerns have been raised regarding the aquatic toxicity and environmental impact of these formulations. In an effort to create a safer dispersant, we have examined the ability of food-grade amphiphiles to disperse (emulsify) crude oil in seawater. Our studies show that an effective emulsifier is obtained by combining two such amphiphiles: lecithin (L), a phospholipid extracted from soybeans, and Tween 80 (T), a surfactant used in many food products including ice cream. Interestingly, we find that L/T blends show a synergistic effect, i.e., their combination is an effective emulsifier, but neither L or T is effective on its own. This synergy is maximized at a 60/40 weight ratio of L/T and is attributed to the following reasons: (i) L and T pack closely at the oil-water interface; (ii) L has a low tendency to desorb, which fortifies the interfacial film; and (iii) the large headgroup of T provides steric repulsions between the oil droplets and prevents their coalescence. A comparison of L/T with Corexit 9500A shows that the former leads to smaller oil droplets that remain stable to coalescence for a much longer time. The smaller size and stability of crude oil droplets are believed to be important to their dispersion and eventual microbial degradation in the ocean. Our findings suggest that L/T blends could potentially be a viable alternative for the dispersion of oil spills.

Oil Pollution in the Marine Environment II: Fates and Effects of Oil Spills

Part I of this three-part set of articles focused on the various types and amounts of oil inputs to the marine environment. The complexity of the mixture of chemicals making up crude oils, fuel oil...

Properties, Preparation and Application of Oil Spill Dispersant

The oil spill dispersant called “elimination agent of oil” is used to disperse the oil slicks to facilitate the natural elimination of oil. Oil spill dispersants are used to enhance the rate of natural dispersion of an oil spill at sea. There is growing acceptance worldwide that use of dispersants to counter the effects of an oil spill offers many advantages and can often result in a net environmental benefit when considered in relation to other response options. Timely spraying oil spill dispersants is the main measures to remove surface oil pollution and to prevent fires, when mechanical recycling cannot be used in case of emergency. Efficient and environmentally friendly oil spill dispersant meet both the emulsification dispersion and zero pollution to the environment, and has been more widely used and developed.

The role of dispersants’ dynamic interfacial tension in effective crude oil spill dispersion

The dispersion effectiveness of dispersants containing Tween 80, Span 80, and dioctyl sodium sulfosuccinate (DOSS) was characterized using a modified Swirling Flask test, and was correlated with both initial and dynamic interfacial tension produced by those dispersants at an oil–water interface. Compositional trends in effectiveness were shown to be governed by: (1) initial oil–water interfacial tension observed upon dispersant–oil–saltwater contact; (2) rate of increase (or decrease) from the initial interfacial tension as DOSS was rapidly lost to the aqueous phase; and (3) gradually slowing kinetics of dispersant adsorption to the oil–water interface as Span 80 concentration was increased, which ultimately diminished dispersion effectiveness considerably even as dynamic interfacial tension remained <10−3mN/m. It is proposed that this third phenomenon results not only from the hydrophobicity of Span 80, but also from the dependence of mixed Tween–Span–DOSS reverse micelles’ stability in crude oil on dispersant composition.

Effects of surface-engineered nanoparticle-based dispersants for marine oil spills on the model organism Artemia franciscana.

Fine particles are under active consideration as alternatives to chemical dispersants for large-scale petroleum spills. Fine carbon particles with engineered surface chemistry have been shown to stabilize oil-in-water emulsions, but the environmental impacts of large-scale particle introduction to the marine environment are unknown. Here we study the impact of surface-engineered carbon-black materials on brine shrimp (Artemia franciscana) as a model marine microcrustacean. Mortality was characterized at 50–1000 mg/L, and levels of heat shock protein 70 (hsp70) were characterized at sublethal particle concentrations (25–50 mg/L). Functionalized carbon black (CB) nanoparticles were found to be nontoxic at all concentrations, while hydrophobic (annealed) and as-produced CB induced adverse effects at high concentrations. CB was also shown to adsorb benzene, a model hydrocarbon representing the more soluble and toxic low-molecular weight aromatic fraction of petroleum, but the extent of adsorption was insufficient to mitigate benzene toxicity to Artemia in coexposure experiments. At lower benzene concentrations (25–75 mg/L), coexposure with annealed and as-produced CB increased hsp70 protein levels. This study suggests that surface functionalization for increased hydrophilicity can not only improve the performance of CB-based dispersants but also reduce their adverse environmental impacts on marine organisms.

Dispersant-Related Oil Spill Response Communication Tools: Toward an Enhanced Approach to Conveying Complex Topics in an Approachable Manner

ABSTRACT During the response to the Macondo Well release in the Gulf of Mexico in 2010, it became evident fairly quickly that there was a potential disconnect between existing scientifically-based information relating to the use of oil spill dispersants and the information that was readily available to the general public, the media, and government officials. At best, both sets of information were aligned and provided a valuable perspective to those who sought an increased understanding of the workings of oil spill response tools. At worst, there was a large misalignment and the information that was available to the public did not accurately reflect the known science of what dispersants have been designed to achieve. In this latter case, conclusions about dispersant use may have been formed incorrectly, providing a backdrop upon which individuals were not able to develop an informed opinion regarding the use of dispersants. In the case where incomplete and potentially unbalanced information is used to inform the public, it is possible that negative effects will result, i.e., opinions may be formed based on fear of the unknown, causing a delayed or less than optimal decision making process. While it is recognized that decisions made during a spill response may be challenging and may involve an environmental trade-off, an informed public can be a valuable asset during the stages of an emergency response when the pros and cons of the specific response options are being debated. To assist with an informed dialog, it is important to have materials available that accurately reflect the scientific principles upon which they are based, but without requiring extensive study of their details for a general understanding of their primary assumptions and conclusions. This paper summarizes recent efforts to develop readily available materials that can provide a better understanding of the use of dispersants during an offshore oil spill response. These efforts have been focused on developing simple yet effective tools which describe dispersants within the framework of an oil spill response tool box and the scenarios in which these tools may be used for the most positive environmental effect.

Studies in support of the regulation of dispersant use in the Kazakhstan Sector of the Caspian Sea (KSCS)

ABSTRACT The use of oil spill dispersants is often regulated by national authorities to ensure that products approved for use as dispersants on spilled oil in national waters are of reasonable effectiveness and of low inherent toxicity. KING (Kazakh Institute of Oil &amp; Gas) undertook a study to assess the use of oil spill dispersants on spilled oils in the Kazakhstan sector of the Caspian Sea (KSCS) to support decision-making for such regulations in the RoK (Republic of Kazakhstan). The KSCS has some characteristics that are unlike open ocean conditions in other parts of the world; the salinity is much lower than in the open sea. The shallow waters of the northern Caspian Sea have very low salinity (9 psu (practical salinity units) or less) due to the inflow of freshwater from the River Volga, and are frozen in winter. The deeper water in the southern part of the KSCS has a salinity of up to 14 psu. The effectiveness of oil spill dispersants is known to be affected by water salinity. Different countries around the world have developed different test methods to assess dispersant effectiveness. The project examined the options and decided to modify the WSL (Warren Spring Laboratory) LR 448 dispersant effectiveness test method, as used in the UK. The method was adapted by KING and testing was conducted by Karaganda State University (KSU) to test a variety of dispersants under Caspian Sea conditions. Dispersant effectiveness testing should be conducted with a test oil that is representative of oils that might be spilled in the area being considered. Kashagan crude oil was distilled to 200°C to simulate the evaporative loss that would occur shortly after the oil was spilled at sea and the residue used as the test oil in the dispersant effectiveness testing. Several commercially-available dispersants were tested using the modified LR 448 method with the 200°C+ Kashagan test oil under a variety of conditions with salinities ranging from 0 psu to 35 psu and at temperatures of 5°C and 25°C. The results indicate that some internationally recognized dispersants could be suitable for use in the KSCS.

Fundamental Aspects of the Science and Engineering of Oil Spill Dispersant Systems: An Overview of Recent Research Activities of the Gulf of Mexico Research Initiative-funded CMEDS Project

ABSTRACT Upon consideration of dispersant-related research, both before and after the Macondo Well oil release, it can be divided into two general categories: (1) the fundamentals of how dispersants work and the effects that may result from their use (e.g., physicochemical and transport characteristics of drops, bubbles, hydrates, surfactants), and (2) an applied focus that has emphasized the design of new dispersants or an enhancement of the performance of those products that are currently available. While there is an extensive amount of data relating to dispersants, a main focus has been on the demonstration of their effectiveness in bench tests and examination of the toxicity of dispersants and dispersed oil. As a result, there is a need for an enhanced understanding of dispersant and dispersed oil thermodynamics and their fate and transport, with a goal to translate the science and engineering to the development of new, effective dispersant systems. The focus of the work to be discussed addresses the following areas: Formation of small oil droplets: Widely dispersed stable oil droplets in the water column are easily accessible to microbes and therefore highly susceptible to degradation. It is important therefore, to understand the fundamental mechanisms of oil breakup and colloidal stabilization in order to develop new and effective dispersants. Dispersant-related processes under deep sea conditions: Current dispersants have been developed for surface spills. The efficacy of such formulations when applied at the high pressures and low temperatures representative of deep ocean release has not been systematically studied. Because of concomitant gas release at the discharge point, and the pressures involved, the liquid droplet is essentially a gas-expanded liquid which could behave quite differently when treated with dispersant components depending upon how they partition at the phase interfaces, i.e., gas/water, gas/oil, oil/water. Fluid mechanics of stabilized oil droplets: Droplet transport, as influenced by all thermodynamic variables of relevance under deep sea conditions, is being studied. Droplet interactions with solid particulates: A better understanding of these processes, either in marine sediments or in the water column, will help predict the environmental fate of the droplets. Development of alternative dispersants: Based on the knowledge gained with respect to the fundamentals, a key goal is the systematic translation of that understanding to the development of new and improved materials. This paper summarizes recent work of a collaborative research effort involving investigators from 22 universities, with particular emphasis on increasing the understanding of the science and engineering of oil spill dispersants.

Three dimensional simulation of transport and fate of oil spill under wave induced circulation

An oil spill model is developed and coupled to a current-wave model to simulate oil spill transport in aquatic environments where waves are present. The oil spill model incorporates physical–chemical processes of oil spill, and simulates oil slick transport by a circulation-driven Lagrangian Parcel model. Using the coupled oil spill model and the current-wave model CH3D-SWAN, a laboratory observed wave induced circulation and oil slick evolution are successfully simulated, while different current-wave coupling schemes generate different flow patterns and oil slick evolution. The modeling system is also shown to simulate Langmuir circulation and resulting oil slicks. Hypothetical scenarios of oil spill near Virginia coast during Hurricane Isabel and Irene are simulated using the oil spill model and the CH3D-Storm Surge Modeling System to assess the role of storm waves during oil spill. The spill area is significantly larger when storm waves are considered, implying waves significantly increase oil spill dispersion.

OPTICAL PROPERTIES OF CRUDE OIL DETECTED IN SEAWATER

The effects of crude oils entering marine environment have been investigated since early 1960s when oil pollution became a subject of global environmental concern. Extraction and transportation of crude oils have been contributing to water pollution especially in closed water basins, such as the Baltic Sea. It was estimated that yearly oil input to the Baltic Sea amounts to 21-70 thousands of tons, which is twice higher than in the North Sea and three times higher than in the North Atlantic. Growing pollution loads into the Baltic Sea created a demand for multifarious studies on the environmental effects of oil products. In this study, we focus on bio-optical and ecological aspects of the presence of crude oil in seawater. Dispersed oil droplets occur in seawater as the result of contaminated river inflows, bilge water discharges and as the consequence of mechanical and chemical dispersion of oil spills. Their optical properties depend on oil type, concentration and size distribution. We present further results obtained from the developed fluorescence-based method for determination of the crude oil concentration in natural Baltic seawater and for evaluation of the oil droplets size by applying vacuum filtering. The results have been measured for the samples collected in Southern Baltic Sea during several ship cruises in 2012. We discuss the application of vacuum filtering in the fluorescence analyses in the context of laboratory, in situ and remote detection of dispersed oil.

FLUORESCENCE PROPERTIES OF MECHANICALLY DISPERSED CRUDE OIL

Despite of numerous actions undertook by the global and local authorities towards protection of marine environment, oil pollution loads into the Baltic Sea still tend to increase and need to be continuously estimated in order to apply the legal regulations. There is a demand for multifarious studies on the environmental effects of oil products. Dispersed oil droplets occur in seawater as the result of contaminated river inflows, bilge water discharges and as the consequence of mechanical and chemical dispersion of oil spills. Their optical properties depend on oil type, concentration and size distribution. Oil content influences many environmental factors, like water quality and bio-optical parameters (e.g. water-leaving radiance, inherent optical properties, seawater fluorescence). We present a unique study of the collected database of crude oil fluorescence spectra for better understanding the correlations between oil optical properties and its concentration, as well as for evaluation of the oil droplets size by the application of vacuum filtering using three filters of different permeability. Fluorescence spectra have been registered for oil-in-water emulsion samples prepared in the laboratory by mechanical dispersion. We discuss the optical properties of crude oil and the relationships between them in the context of potential remote detection of dispersed oil in seawater.

Utilization of oleo-chemical industry by-products for biosurfactant production

Biosurfactants are the surface active compounds produced by micro-organisms. The eco-friendly and biodegradable nature of biosurfactants makes their usage more advantageous over chemical surfactants. Biosurfactants encompass the properties of dropping surface tension, stabilizing emulsions, promoting foaming and are usually non- toxic and biodegradable. Biosurfactants offer advantages over their synthetic counterparts in many applications ranging from environmental, food, and biomedical, cosmetic and pharmaceutical industries. The important environmental applications of biosurfactants include bioremediation and dispersion of oil spills, enhanced oil recovery and transfer of crude oil. The emphasis of present review shall be with reference to the commercial production, current developments and future perspectives of a variety of approaches of biosurfactant production from the micro-organisms isolated from various oil- contaminated sites and from the by-products of oleo-chemical industry wastes/ by-products viz. used edible oil, industrial residues, acid oil, deodorizer distillate, soap-stock etc.

Synthesis of Some Oil Spill Dispersants From Locally Alkyl Benzene and Evaluating Their Dispersion Efficiency and Toxicity

Seven surface-active agents used as oil spill dispersants were prepared based on linear alkyl benzene-N-hydroxyl ethyl sulfonamide. Five of them are nonionic and the other two are ionic. These surfactants were prepared from locally raw materials. Their chemical structure and surface-active properties were investigated using the FT-IR, surface tension, and interfacial tension measurements. The efficiency of these dispersants was compared with a commercial used dispersant from Dasic Company. The toxicity test was carried out using aquatic animal (Modiolus adriaticus). The animal was exposed to these dispersants for 120 h at different dispersant to oil ratio. From the obtained results it was found that, the percentage of mortality of mussels after 1-h exposure from the start of the tests equalized zero. It varied with passing time up to 120 h, at which the mortality rate became 50%.

A protocol for assessing the effectiveness of oil spill dispersants in stimulating the biodegradation of oil

Dispersants are important tools in oil spill response. Taking advantage of the energy in even small waves, they disperse floating oil slicks into tiny droplets (<70 μm) that entrain in the water column and drift apart so that they do not re-agglomerate to re-form a floating slick. The dramatically increased surface area allows microbial access to much more of the oil, and diffusion and dilution lead to oil concentrations where natural background levels of biologically available oxygen, nitrogen, and phosphorus are sufficient for microbial growth and oil consumption. Dispersants are only used on substantial spills in relatively deep water (usually >10 m), conditions that are impossible to replicate in the laboratory. To date, laboratory experiments aimed at following the biodegradation of dispersed oil usually show only minimal stimulation of the rate of biodegradation, but principally because the oil in these experiments disperses fairly effectively without dispersant. What is needed is a test protocol that allows comparison between an untreated slick that remains on the water surface during the entire biodegradation study and dispersant-treated oil that remains in the water column as small dispersed oil droplets. We show here that when this is accomplished, the rate of biodegradation is dramatically stimulated by an effective dispersant, Corexit 9500®. Further development of this approach might result in a useful tool for comparing the full benefits of different dispersants.

Influence of Pseudomonas aeruginosa Presence in the Biodegradability study of Solvent‐based and Water‐based Dispersant in Oil Spill Handling

Oil-Spill Dispersant (OSD) reduces interfacial tensions of oil and water turning oil spill into droplets that makes crude oil easier to be degraded by hydrocarbonoclastic bacteria such as Pseudomonas aeruginosa. The purpose of this study is to assess the effect of dispersant utilization (solvent-based and water-based) related its performance efficiency in the presence of Pseudomonas aeruginosa. The research was carrried out in laboratory, varying Dispersant-Oil Ratio (DOR) into 3 levels (1:8, 1:20, 1:25) and carbon source adaptation into 3 levels (0%, 1%, 2%). The total number of samples prepared was 84, consist of 21 samples without Pseudomonas aeruginosa addition and 63 samples with Pseudomonas aeruginosa addition. Total petroleum hydrocarbon (TPH) is measured using gravimetric method to determine the biodegradation of crude oil. Also measured are pH of samples with Pseudomonas aeruginosa addition and COD (Chemical Oxygen Demand) value of samples with dispersants. Data were evaluated using ANOVA. The result shows Pseudomonas aeruginosa has the ability to degrades crude oil despite the presence of dispersant, whereas the use of water-based dispersant showed better biodegradation ability than solvent-based OSD usage. Dispersant effectiveness of solvent-based and water-based is 33% and biodegradation by Pseudomonas aeruginosa achieved 25% in 72 hours.

Mesocosm study on weathering characteristics of Iranian Heavy crude oil with and without dispersants

The environmental fate of Iranian Heavy crude oil (IHC) with and without an added oil spill dispersant (OSD) has been studied using a 1000kL capacity in situ mesocosm. Physical weathering and chemical composition changes of the oil were monitored for 77 days. Compound-specific effects of the OSD could be observed as changes over time in the content of the total petroleum hydrocarbon (TPH), unresolved complex mixture (UCM), alkanes, polycyclic aromatic hydrocarbons (PAHs), hopanes and steranes in the oil. As oil weathers, most hydrocarbons showed a rapid decreasing phase followed by a slowdown and stabilization. Recalcitrant biomarkers, however, showed a different trend. An increase in hydrocarbon contents in the form of UCM occurred after OSD treatment. The enhanced solubility of the low molecular weight PAHs by the OSD decreased the half-life of the alkylated PAHs in the OD. After 77 days of exposure at the sea surface, both the oils with and without the OSD exhibited moderate weathering. Most of the source diagnostic indices maintained their source information, and the weathering indices indicated that evaporation, dissolution, and dispersion were the major weathering processes. The mass balance of the weathered oil was calculated using laboratory and mesocosm data and the results demonstrate the importance of using a mesocosm for the production of environmentally realistic data.

Mathematical Model and Computer Simulation for Oil Spill in Ice Waters Around Island Based on FLUENT

The simulation of oil spill in ice waters was built by computational liquid dynamic software FLUENT. The coupling of pressure and velocity under unsteady-state conditions was solved by pressure implicit with splitting of operator algorithm. The boundary conditions of nonlinear free surface were solved by volume of fluid. And the numerical wave water flume was established by the user defined function with the help of C programming language. The whole process of the dispersion and diffusion of oil spill in ice waters was shown vividly and visually on screen in graphic mode dynamically. Also the distribution of velocity vector could be obtained. Basing on this intelligence simulation method, the movement characteristics of oil spill in ice waters were analyzed. The results showed that: with the ice sheet, the oil adhered to the ice lower surface easily, while its diffusion area was less than the one on the free sea surface in the same temperature; some oil was entrained to the ice upper surface and continued to transport, which accelerated the ice melting; the pollution area caused by oil spill near to the ice sheet was less than the one caused by oil spill far from the ice sheet. These simulation results were similar to some experimental phenomena and this computational method was validated to be effective. Index Terms—simulation, algorithm, ice waters, oil spill, software FLUENT

Development of High Efficient and Low Toxic Oil Spill Dispersants based on Sorbitol Derivants Nonionic Surfactants and Glycolipid Biosurfactants

Dispersants, usually blending with several surfactants and a solvent, are used to enhance oil spill dispersion as small droplets in water column. Although there is growing acceptance of dispersants as a counter measure to marine oil spills around the world, the two major issues with the dispersants are their toxicity to marine life and dispersion effectiveness (DE) for crude-oil, especially for heavy oil. To develop more efficient and less toxic dispersants, two kinds of sorbitol derivant nonionic surfactant (polysorbate 85 and sorbeth-40 tetraoleate), two kinds of glycolipid biosurfactants (rhamnolipid and sophorolipid) and less toxic solvent ethylene glycol butyl ether were chosen in this study, and two dispersant formulations were optimized by uniform design methods. Effects of dispersant-to-oil ratio, temperature, salinity and pH on the performance of the two optimized dispersants were investigated. The two dispersants had high dispersion effectiveness (DE) for heavy crude oil, while both dispersants keep high DE at the dispersant-to-oil ratio below 1:25 and the temperature above 5 ℃. In addition, the two dispersants also performed well in a wide range of salinity and pH values. Finally, toxicity tests revealed that the two dispersants showed low toxicity to two kinds of fish (Danio rerio and Microgobius gulosus).

Value of Dispersants for Offshore-Oil-Spill Response

This article, written by Senior Technology Editor Dennis Denney, contains highlights of paper OTC 23359, ’The Value of Dispersants for Offshore-Oil-Spill Response,’ by Tim Nedwed, Tom Coolbaugh, and Greg Demarco, ExxonMobil, prepared for the 2012 Offshore Technology Conference, Houston, 30 April-3 May. The paper has not been peer reviewed. Each oil-spill-response option must be evaluated for operational limitations (e.g., sea state), potential effectiveness, environmental effects of the response option, applicability under various oil-spill scenarios (e.g., size and location of the spill), and health and safety of the responders. Alternative response tools are available to assist mechanical recovery in treating large offshore oil spills more effectively. There are misperceptions and misunderstandings about dispersants and their use; therefore, a description of dispersant use during the Deepwater Horizon incident is presented. Introduction The primary goal of any oil-spill response should be to minimize environmental harm. Although one expectation may be complete physical containment and removal of oil from the environment, this often is not possible (especially with large offshore spills) because of physical limitations of mechanical-recovery systems. Recovery operations during previous offshore spills collected only a small fraction of the spilled oil, even under ideal conditions. The Deepwater Horizon incident was no exception, with estimates indicating that only 3% of the oil was recovered mechanically. Recognizing significant limitations of mechanical recovery has led to developing alternative response tools—one of which is oil-spill dispersants. Oil-spill dispersants facilitate removal of oil from the environment by enhancing the natural biodegradation process. Dispersants break up a surface slick rapidly into micron-sized droplets that move into the water column. This action provides naturally occurring oil-degrading bacteria greater access to the oil by creating a dilute mixture of oil in water rather than a thick surface accumulation. Fortunately, oil-degrading bacteria exist in all marine environments, having evolved to degrade oil released by natural seeps. Dispersed oil dilutes rapidly, and concentrations above known toxicity thresholds persist for no more than a few hours after effective dispersant application. During the Deepwater Horizon incident, the amount of damage to the shorelines was far less than expected initially by the public. In many locations where oil did enter, marsh-grass recovery was apparent soon after the spill. This, and other evidence, suggests that a key reason for the limited shoreline effects during the incident was use of dispersants and, in particular, the subsea injection of dispersants at the wellhead. Oil Behavior During High-Flow Subsea Release The lower the viscosity of the oil, the higher the flow rate, and vice versa. Also, the ability to disperse oil is inversely related to the fluid’s viscosity, and oils remain readily dispersible with viscosities up to several thousand centipoises.

Biodegradable Polyoxyethylenated Pentaerythritol Quaternary Esters as Oil Spill Dispersants

Abstract Four polyoxyethylenated pentaerythritol (PE) ester surfactants have been synthesized. The molecular weights of these surfactants were calculated and evaluated experimentally by GPC and confirmed by calculations based on 1H-NMR. Also, their HLB values were calculated by Griffin formula. The surface tension and thermodynamic properties of the surfactants were obtained from surface tension measurements at different temperatures (298 – 318 K). It was found that the minimum area/surfactant molecule (Amin) for the investigated surfactants increased with increasing the molecular weight of the incorporated ethylene oxide. The thermodynamic parameters of micellization (ΔGmic, ΔHmic and ΔSmic) and that for adsorption (ΔGad, ΔHad and ΔSad) were also calculated. The more negative Gibbs free energy of adsorption values than those of micellization suggest that these surfactants favor adsorption than micellization. This finding is utilized for monitoring their dispersancy power. It was found that the water solubility of the prepared surfactants is correlated to their HLB values. Furthermore, the biodegradability of the prepared compounds was studied at different conditions in order to investigate their usability as oil spill dispersants. The data revealed that PE200-C12 had maximum dispersion efficiency and it was completely biodegraded after 8 days.