Program Director's Recommendation Center for Particulate and Surfactant Systems (CPaSS) Proposal # 1230367 & 1230680 Moudgil and Somasundaran
This proposal seeks funding for the Center for Partculate and Surfactant Systems (CPaSS) located at the University of Florida (lead site) and Columbia University. Funding Requests for Fundamental Research are authorized by an NSF approved solicitation, NSF 11-570. The solicitation invites I/UCRCs to submit proposals for support of industry-defined fundamental research.
This proposal will investigate foaming properties of green surfactants and the effects of presence of fine particles on foaming and frothing behavior. The primary goals of the proposal are 1)to understand physico-chemical aspects of the foaming/defoaming properties of green surfactant formulations and surface modified fine particles; 2)study the structure of surfactant films at the liquid-gas and solid-liquid interfaces; and 3)to develop efficient foaming/defoaming formulations. Experiments will involve the macroscopic measurements of foam/froth stability and a vibrational FTIR and Raman) spectroscopic study of the molecular organization of green surfactants in the liquid films of foams. A new FTIR spectroscopic method will be employed to acquire spectra of unstable bubbles. Dissipative Particle Dynamics (DPD) computational simulation will be used to simulate the green surfactant systems. The DPD modeling will be adapted to facilitate interpretation of experimental data.
Results of this study will advance the fundamental understanding of the parameters that govern the antagonistic and synergistic effects of green surfactant formulations and their mixtures with modified fine particles on the foamability, frothing, and defoaming of the solutions and suspensions. The industries interested in the proposed fundamental studies include green surfactant producers, mineral processing, petroleum, paints and coatings industries, biochemical separation, cosmetics, personal care, and household products industries, as well as those interested in the environmental remediation. Specifically, a comprehensive understanding of the foam stability of green surfactants will lead to the development of new formulas for their applications in personal care and cosmetics products, while the knowledge about the fine particles interactions with green surfactants will lead to the development of cost effective foaming, frothing, and de-foaming systems.
The formation and stabilization of liquid foams from surfactant solutions and their interactions with hydrophobically modified particles have long been studied in foam science. However, the foaming properties, such as foamability and stability, of novel greener surfactants and the interactions between their foams with nanoparticles have remained poorly explored. This research is the first study performed on these systems using both experimental and theoretical approaches. Results of this study have advanced the fundamental understanding of (1) the interactions that govern the synergistic and antagonistic interactions among the new generation of greener surfactants; (2) the parameters that govern the antagonistic and synergistic effect of nanoparticles on the frothing/de-frothing properties of the new surfactants. These results have opened new possibilities in the industrial applications of the surfactants studied. The project also has promoted innovations in adapting existing research methods and developing new characterization tools for studying the interactions of nanoheterogeneous substrates with surfactants. The results and findings from the research have been summarized in a manuscript titled "Foaming and Frothing Behaviors of Greener Surfactants and Hydrophobically Modified Fine Particulate Systems", which is under preparation by both Columbia University and University of Florida teams. The results and findings from the research have been presented in the following forms: Presentations to the members of the industrial advisory board of the center in the meetings hold in February 2013, August 2013, February 2014, and August 2014. Posters in 2013 and 2014 annual green chemistry & engineering conference ACS GCI roundtable poster reception. Presentation in 2013 NY Society of Cosmetic Chemists technology transfer conference poster session, received the 3rd place award. Chapters in two books: Surface and Colloid Chemistry (September 2013) and Surfactant Science and Technology: Retrospects and Prospects (May 2014) Materials into two classes taught at Columbia University: Introduction to Colloidal and Interfacial Science and Advanced Colloidal and Interfacial Science. One new postdoc has been trained in this project, who has been exposed to various aspects of research, including green chemistry, green engineering principles, life cycle assessment, environmental engineering, and interfacial and colloidal chemistry. The postdoc has been involved in the interactions with the PI at the NSF Center for Particulate and Surfactant Systems and many of the industrial partners. The postdoc also has been interacting with the research and academic staff in University of Florida, the joint-CPaSS Center, and of other relevant faculty at Columbia University. One research associate (woman) was supported by the project. She was developing the advanced vibrational (FTIR and Raman) spectroscopy methods of characterization of the surfactant structures in foams. She also performed DFT modeling of the surfactant packing. The funds were also used to support her presentations in 243rd, 244th, and 245th ACS Meetings. The multidisciplinary and exciting subject of the research has attracted talented undergraduates and graduate students as well as researchers, including those from underrepresented groups, into colloidal/interfacial science and nanoscience. One dedicated instrument, Foamsacan, for foam studies and operation procedures to use the machine have been established in PI’s lab. The instrument expanded the capability of the PI’s lab to carry out scientific research on surfactants and foams. The equipment is also used for demos in PI’s classes, in which students are exposured to colloidal and interfacial science. Contribution to the society: surfactants are one of the most widely used chemicals. The annual global production of surfactant passed 13 million metric tons in 2008. The applications include household cleaners and detergents, Industrial cleaners, body care products and cosmetics, and other industrial applications, such as agrochemicals, photo chemicals, oil field chemicals, construction materials, foodstuffs, adhesives, lubricants as well as metalworking, mining, and pulp & paper reagents. Increased requirements for environmental protection demand more sustainable and efficient greener surfactants as alternatives. In this research, several greener surfactants have been studied to evaluate their foaming properties versus petroleum based conventional surfactant system. Greener formulations, made from these less hazardous and more degradable surfactants, have been identified to provide the same performance. Moreover, the synergism has been identified among those surfactants for property enhancement, which will leads to less dosages in their application, and hence reduce their chemical footprints. The greener formulations have been recommended for applications in personal care and mining industries to provide economy, environment, and society benefits. In reaction to the epidemic outbreak of Ebola in Africa and potential risks in the US, strong demands for effective disinfectants for decontamination emerged. The conventional approaches, which use oxidative disinfectants such as hydrogen peroxide and peracetic acid, phenols, and iodophors, are cumbersome and some of them represent toxic hazard to the staff. For the most part, intermediate and low level disinfectants cannot be safely used. The findings from this research have been successfully applied to develop a decontamination foam to fight Ebola virus. A prototype (formulation and delivery device) has been designed and used in recent drills with FDNY.
