Ethoxylated Surfactants and Why We Do Not Use Them
Many surfactants that have USFDA 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.
However, ethoxylated nonylphenols are suspected of producing an estrogen-mimicking agent as a biodegradation byproduct, and are banned in Northern Europe. Additionally, the ethoxylation process may produce trace levels of dioxane, and California requires a product level stating, “This product may contain a cancer causing chemical” if the product has not been tested for the presence of dioxane. As a result, we do not use any of these surfactants in our vegetable oil based electron donor (EDS-ER™) or our TASK™ formulations. We also do not use them in our TASK™ formulations for surfactant enhanced aquifer remediation because in general, they have higher levels of adsorption than anionic surfactants. This makes it harder to get to very low levels of residual soil concentrations when soil contaminant levels are important in determining whether a site can be closed.
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. Our 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 bioremediation and sustainable remediation technologies. This half-day seminar is offered at No Cost to you that 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.
It is difficult to verify the presence of DNAPLs through direct observation. A common practice is to estimate the presence of DNAPLs indirectly by applying the “1 percent of solubility” rule-of-thumb (EPA, 1992). Under this approach, DNAPL is suspected to be present when the concentration of a chemical in groundwater is greater than 1 percent of its pure-phase solubility. For example, PCE is inferred to be present as a DNAPL when the concentration of PCE is greater than 2,000 micrograms per liter (μg/L) in the dissolved phase (1 percent of its pure-phase solubility of 200,000 μg/L).
Suspected DNAPL Thresholds Based on Solubility Relative to 1 Percent of Aqueous Solubility
|Chlorinated Solvent (CAS Number)||
1% of Aqueous Solubility
|Vinyl Chloride (75-01-4)||
|Carbon Tetrachloride (56-23-5)||
|Methylene Chloride (75-09-2)||
- The reference temperature is 20 oC for the properties of these compounds.
- Source for Aqueous Solubility: EPA. 2004. In Situ Thermal Treatment of Chlorinated Solvents – Fundamentals and Field Applications. EPA 542-R-04-010.
- Source for 1 Percent Rule-of-Thumb: EPA. 1992. Estimating Potential for Occurrence of DNAPL at Superfund Sites. OSWER Publication 9355.4-07FS. NTIS Order Number PB92963338CDH.
DCA – Dichloroethane
DCE – Dichloroethene
PCE – Tetrachloroethene
TCA – Trichloroethane
TCE – Trichloroethene
In Jacksonville, Florida, the 2nd Annual Bioremediation and Sustainable Environmental Technologies Symposium allowed professionals and scientists to gather and discuss the latest trends in the contaminated site remediation industry.
Listed below are a few presentations featuring Tersus’ Technologies that you might find of interest:
- Platform presentation:Managing Geochemistry and Hydrogeology While Performing Anaerobic Bioremediation¸Presented by Mark Dockum. An EDS-ER and Nutrimens case study in California. Link
- Platform presentation: Cometabolic Bioremediation of 1,4-Dioxane presented by Randy Pratt. GSI presented results on how iSOC Technology was used to deliver oxygen, propane, nitrogen and nitrous oxide gases in groundwater to treat this recalcitrant contaminant. Link
- Poster: In Situ Treatment of a Downgradient Landfill Plume Using an Aerobic Permeable Reactive Barrier, presented by David Alden. The iSOC Technology offered an efficient and safe, low impact, low cost solution. Link
- Platform presentation:Emulsified Zero-Valent Iron (EZVI): A Combination Technology for Source Zone Remediation, presented by Greg Booth, who showed case studies and a technology overview of Tersus’s source zone solution. Link
- Platform presentation:Three Phased Remedial Approach Utilizing Multiple Degradation Pathways and Reductive Amendments To Remediate 1,1,1-TCA and TCE, presented by Patrick Gratton. This was AECOM’s presentation on a brilliant approach to remediate complex site taking advantage of local geochemical conditions. Link
- Platform presentation: Evaluation of B-12 and Nutrient Addition as Part of a Maintenance Injection to an Enhanced Reductive Dechlorination (ERD) Biobarrier, presented by Mike Kovacich. Mike with Tetra Tech showed important lessons learned from a case study. Link
- Poster: Vapor Intrusion Mitigation by Sustainable Soil Vapor Extraction, featuring Tersus’ MicroBlower, presented by Gary Birk. Link
- Poster: Cost-Effective Site Remediation Strategies: A Community-Supported Sustainable Model That Works with Even a Limited Budget, presented by Jymalin Redmond. The MicroBlower perfectly complied with the objectives of this interesting project. Link
Congratulations to this year’s student paper competition winners: Carol Beaver, Beni Camacho-Perez, Dimin Fan, Jeffrey Heenan, Kamaraj Satish-Kumar and Yi Zhang.
We would like to thank the organizers for another successful event. Key figures in our industry had an opportunity to meet and share valuable information, which in turn will drive the environmental industry towards finding more efficient, and cost effective remediation goals.
We look forward to seeing you at next year’s symposium on Chlorinated and Recalcitrant Compounds in Monterey, California.
ST. PAUL, MINNESOTA and WAKE FOREST, NORTH CAROLINA — Antea®Group, a global engineering and environmental consulting firm, and Tersus Environmental announced today the signing of an Exclusive License Agreement for US Patent No. 7138060. Under the terms of the agreement, Tersus Environmental will make, market, promote and sell products for sulfate-enhanced bioremediation of contaminated groundwater. The patent includes a process for using high concentrations of sulfate to stimulate biodegradation of petroleum hydrocarbons (PHCs), other aromatic hydrocarbons and other contaminants susceptible to sulfate-reducing bacteria.
“This license agreement with Antea®Group enables us to further expand our strong foundation of intellectual property,” says Tersus’ Managing Partner, Gary Birk. Our joint resources give Tersus customers the best biotechnology-based solutions to manage complex, challenging environmental liabilities and reduce costs for site closure.”
“We are keen to work with Tersus,” says Mike Martinson, Senior Consultant, Antea®Group. “Tersus’ network of sales associates and staff around the world will help provide a much broader market coverage for our sulfate enhanced technology.”
Enhanced aerobic bioremediation technologies such as the iSOC® gas inFusion technology or the use of oxygen releasing compounds such as TersOx™ are commonly used to accelerate naturally occurring in situ bioremediation of petroleum hydrocarbons, and fuel oxygenates such as MTBE and TBA, by indigenous microorganisms in the subsurface. However, these indigenous microorganisms do not function well in the high contaminant concentrations of the source area. Moreover, the oxygen technologies have to overcome the anaerobic conditions of the source area and often the presence of iron.
Antea®Group developed and proved a sulfate-enhanced in situ remediation strategy to address the anaerobic portion of the plume. Sulfate reduction and methanogenesis appear to dominate natural degradation processes at most sites; and therefore, adding oxygen to the anaerobic portion of the plume may be disadvantageous. The sulfate-enhanced technology, now marketed by Tersus Environmental under the name Nutrisulfate™, stimulates biodegradation by providing a soluble, readily available electron acceptor solution. In the presence of elevated sulfate, anaerobic groundwater bacteria use BTEX, MTBE and other petroleum hydrocarbons for carbon and energy while mineralizing the hydrocarbons to carbon dioxide and water. Sulfate addition enhances natural conditions and reduces the carbon footprint when compared to conventional remediation. Nutrisulfate™ is a high sulfate metabolic supplement designed to enhance the kinetics and efficiency of microbial systems specifically related to bioremediation. The increase in kinetics and efficiency decreases the remediation time and reduces the amount of substrate / amendment required.
“Deploying Nutrisulfate™ in the anaerobic source zone and one of our oxygen technologies such as iSOC® gas inFusion technology in the perimeter or outskirts of the plume gives Tersus customers the best biotechnology-based solutions to manage complex, challenging environmental liabilities. The use of these two solutions in combination speeds site closure, reduces costs, and leaves the site in an aerobic state precluding the risk of liberating unwanted substances. It’s a game changer,” says Birk.
Antea®Group is an international engineering and environmental consulting firm specializing in full-service solutions in the fields of environment, infrastructure, urban planning and water. Antea®Group includes the Belgian, Colombian, French, and United States engineering and consultancy operations of Oranjewoud N.V. In the Netherlands, engineering and consultancy services are offered under the nearly 60-year-old brand, Oranjewoud. With access to more than 3,000 employees in over 100 offices around the world and experience on all continents, Antea®Group serves clients ranging from global energy companies and manufacturers to national governments and local municipalities. For more information, visit www.anteagroup.com.
Antea®Group also is a co-founder of Inogen, a global corporation providing multinational organisations with consistent, high quality and cost effective environmental, health and safety solutions to assist our multinational clients. Inogen provides global geographic coverage with 12 Inogen Associate companies located on every continent and collectively more than 4,330 staff worldwide. The Inogen service offerings are reflected with the diversity of our membership. Inogen is able to deliver a broad spectrum of environmental, health and safety related services across the world. Inogen has completed projects in more than 120 countries. www.inogenet.com