Ethoxylated Surfactants and Why we Do Not Use Them
Many surfactants that have US FDA Direct Food Additive status are ethoxylated. Anytime you have an ingredient on your food label that says “polysorbate”, that’s an ethoxylated surfactant. The polysorbate surfactants are made by reacting fatty acids with a sugar molecule, then adding a polyethylene oxide chain to make it more water-soluble.
As you may know, many environmental remediation injectates, such as emulsified vegetable oil and NAPL solubilization compounds, use biodegradable, non-ionic surfactants. ESTCP 2006 and AFCEE 2007 teach how to make emulsified vegetable oil (EVO) for bioremediation using polysorbate, an ethoxylated surfactant. In Appendix H.2, AFCEE 2007 discloses the formula for an EVO product and lists polysorbate as one of the ingredients.
Unfortunately, ethoxylation, the manufacturing process that creates these surfactants (e.g., polysorbates) often results in these products containing 1,4-dioxane. While the FDA has set a limit on 1,4-dioxane at 10 ppm in polysorbates, glycerides and triglycerides, this limit is well above California’s notification level of 1 µg/L for drinking water (CDPH 2011). As a result, we do not use any of these surfactants in our vegetable oil based electron donor (EDS-ER™) or our TASK™ family of surfactants for NAPL recovery.
01/17/2015 – 12/31/2015
various – see website link below for details
Tersus is co-hosting this national remediation lecture series on soil and groundwater remediation technologies.
Our Technology Lecture Series brings a half-day of technical presentations on soil and groundwater remediation by a number of professionals from various organizations. These educational seminars bring together scientists, engineers, regulators, site managers and other environmental professionals from government, academia, service and R&D firms to advance the state-of-the-practice.
We know that NOT all educational events are created equal. We have worked hard to recruit both unique and impressive speakers to make the most of your valuable time. At our seminars you will connect directly with industry leading practitioners as they highlight the latest ideas for contaminant source area delineation, bioremediation and sustainable remediation technologies. You won’t want to miss this seminar!
Tersus and our partners offer these seminars at No Cost to our clients and guests from within the groundwater remediation community. Each seminar includes lunch and a certificate for 4 hours of Continuing Education. Seating for these private events is limited and you must register to attend.
Current locations are listed below:
Nutrimens® Granular, Enhancing the Efficiency of Electron Donor Utilization in Bioremediation
Bacteria are very sensitive to low pH. The optimal pH for bioremediation is between 6 and 8.5. To keep your in situ bioremediation project on track, pH should be maintained within a range where bioremediation is maximized. In general, more fermentation means more volatile fatty acid (VFA) production and lower pH. A major consequence when pH falls below 6 is a dramatic decline in enhanced reductive dechlorination.
One of the unique features of Tersus’ Nutrimens® Granular product is that the product stimulates fermentation resulting in more VFA production. Yet, its impact on pH is minimal. Doto and Liu (2011) reported and increase in total VFA production with increasing amounts of Tersus’ Nutrimens® Granular, while the pH was maintained at a higher or equal level to the control. This change could be a result of more lactate-bacteria that covert lactate to propionate (Callaway and Martin, 1997.).
Since 1943, Tersus’ business partner has been leading the industry in microbial-based fermentation research and technology innovation. The relationship between feed efficiency and methane production is well established in the dairy industry. The use of high quality metabolic nutrients that contain soluble carbohydrates such as Nutrimens® Granular has been shown to alter rumen fermentation, increase efficiency and reduce methane emissions. Nutrimens® Granular may provide the same opportunity to reduce methane production on enhanced reductive dechlorination projects. In 2015 we will continue to evaluate this development and report back to you.
Tersus introduces unique surfactant technology and implementation techniques for complex site remediation.
June 16, 2014.
Surbec Environmental (www.surbec.com) and Tersus Environmental (www.tersusenv.com) announced today the signing of a Distribution Agreement between the two firms. Under the terms of the agreement, Tersus Environmental will market, promote and serve as the worldwide distributor of Surbec’s leading surfactant technology and related products. The patented anionic surfactant formulations have the unique ability to selectively desorb and liberate sorbed petroleum hydrocarbons from soil and fractured bedrock surfaces.
A key efficacy metric for surfactants is the reduction of the interfacial force, which is the force that keeps the oil trapped within pores. Most nonionic surfactants (conventional surfactants) reduce this trapping force by about an order of magnitude. TASK™ (Tersus Advanced Surface Kinetics) reduces the interfacial force by three to four orders of magnitude allowing improved mass recovery and improved treatment by other remediation techniques.
Tersus’ anionic biodegradable surfactants provide considerable advantages.
- Dramatic reduction in cost
- Minimal surfactant mass – usually 0.5 to 0.9 weight percent
- 1 to 1.4 pore volumes for up to 95% mass removal
- The recovered oil and water gravimetrically separate within 30 minutes, making the waste stream easy to handle
- Low-cost solution – less surfactant, low disposal costs.
Supported by nearly two decades of research and formulation testing at the University of Oklahoma, TASK™ can address a wide range of applications related to hydrocarbon contamination, including:
- In situ soil and groundwater remediation
- Emergency spill clean-up
- Pipeline cleaning and spill clean-up
- Tank cleaning and sludge removal
David Alden, Technical Associate with Tersus was a guest panelist on Biotechnologies at the 2014 NC Federal Advanced Technologies Review (NCFATR) held on June 4/5, 2014 in Raleigh, NC. The Federal Advanced Technologies Review focus was on the future advanced technology needs of the Department of Defense (DoD) and other federal agencies within North Carolina. United States Senator Richard Burr, the North Carolina Military Business Center (NCMBC), North Carolina Military Foundation, University of North Carolina and the Institute for Defense and Business hosted the event.
Dune Technologies joins Tersus Environmental as Sales and Marketing Business Partner
Michigan based Dune Technologies will expand its groundwater remediation product line for enhanced bioremediation to include Tersus’ family of bioremediation products. Dune Technologies, led by David Wardwell, will help support Tersus Environmental’s continued commitment to providing outstanding customer service and assistance, helping to ensure superior remediation outcomes.
Dune Technologies offers engineered sustainable solutions to help their clients reduce uncertainty, minimize risks, and achieve cost-effective results.
- Site Evaluation
- Remedial Effectiveness
- Project Summaries
- Cost Estimates
- Feasibility Reports
- Technical Support
Tel 616.459.2849 • Cell 616.450.5788
email Contact Form
Wake Forest, NC, January 7, 2014 – Tersus Environmental, a recognized leader in the development of advanced environmental remediation technologies, announces that it will sponsor complimentary seminars on soil and groundwater remediation technology. The Technology Lecture Series brings a half-day of technical presentations on soil and groundwater remediation by a number of professionals from various organizations. Technology Lecture Series brings together scientists, engineers, regulators, site managers and other environmental professionals from government, academia, service and R&D firms to advance the state of the art of contaminant source area, bioremediation and sustainable remediation technologies. These half-day seminars are offered at No Cost to you and includes lunch and a certificate for 4 hours of Continuing Education.
Sustainability and Economic Advantages of EDS-ER, a Self-Emulsifying Organic Substrate for Enhanced Reductive Dechlorination
Soil and groundwater contaminated by toxic substances pose a threat to human and environmental health. Management of common environmental contaminants that include chlorinated halogenated straight chain and aromatic hydrocarbons such as perchloroethene (PCE), trichloroethene (TCE) and chlorinated phenols, perchlorate, explosive materials such as aromatic nitrates and residues of energetic munitions, nitrates, acids, radionuclides and metal oxides, allows restoring aquifers and the environment to productive use.
It is well known that creating anaerobic groundwater conditions by adding organic substrate stimulates biological mechanisms to degrade the aforementioned contaminants. Once the organic material initially consumes any oxygen and other electron acceptors such as nitrates (NO3-) and sulfates (SO42-), it provides a carbon source and serves as an electron donor during reductive dechlorination of contaminants by indigenous or exogenous microorganisms. Better understanding of the processes undergoing this degradation mechanism has increasingly taken Environmental Engineers, contractors, scientists, consultants, regulatory personnel, and others charged with remediating contaminated groundwater to engineer systems that enhance these biological mechanisms. During these biostimulation practices, emulsified vegetable oils (EVO) are a commonly deployed carbon source for enhanced halorespiration, which is the use of halogenated compounds as sources of energy.
EVO selection and delivery process must, on one hand, favor a substance with appropriate characteristics for subsurface delivery which is important to maximize contaminant contact and minimize the impact on groundwater flow conditions while providing a short and long-term source of hydrogen and carbon for enhanced reductive dechlorination. On the other, sustainability and cost considerations are factors that can determine using a product such as EDS-ER™ which ships as a 100% vegetable oil base solution yet emulsifies on site simply by adding local water without additional high-energy mixing.
EDS-ER™ is a self-emulsifying organic substrate that is an isotropic mixture of vegetable oil and vegetable oil derived fatty acid esters. EDS-ER™ has the unique ability of forming a fine oil-in-water (O/W) emulsion when mixed with water. Spontaneous emulsification to produce fine O/W emulsion occurs since the entropy change favoring dispersion is larger than the energy needed to increase the surface area of dispersion. Emulsification occurs spontaneously due to the relatively low positive or negative free energy required to form the emulsion.
Secondary environmental advantages of using EDS-ER™ include reducing greenhouse gas (GHG) emissions firstly by eliminating mechanical energy inputs and reducing substrate-shipping volumes by up to 50%. Secondly, EDS-ER™ with a long shelf life allows for on-site bulk storage, which reduces the need for excess drums and totes that would require additional energy and materials for recycling or disposal at the conclusion of the project. This non-perishable characteristic of EDS-ER™ allows intermodal or consolidated shipping to reduce transportation carbon footprint. Intermodal carriers can haul one ton of bulk liquid approximately 500 miles on a gallon of fuel, reducing by one-third the GHG emissions of equivalent trucks travelling the same distance.