Applied Separations is a small business based in Allentown, Pennsylvania that has supported greener approaches to chemistry for years. The company manufactures supercritical fluid systems, offers DNA-free laboratory sample preparation consumables and a new CO2 flash chromatography machine.
The deadline for applications for the 2018 Educational Grant is April 30, 2018. Among other considerations, proposals should illustrate how the machine will be used to teach supercritical fluids in the college classroom, with an emphasis on green chemistry and environmentally friendly processes. Learn more about how to apply.
Supercritical Fluids as Supporting Research into the Origins of Life
One of the past winners of this award is Professor Michael Gaylor of Dakota State University who has seen the Prime system positively influence his teaching, research and even recruitment of new chemistry students. “Engaging in supercritical fluids teaching and research mentoring introduces students to a sophisticated field of chemical study that substantially expands their theoretical and experimental skill sets,” says Professor Gaylor. “I’ve seen this pay big dividends for my students heading into industry labs and graduate programs by giving them an advantage over the competition.”
One of Professor Gaylor’s research areas is investigating the high-pressure origins of life. The Prime system has enabled him to simulate deep-sea hydrothermal vent conditions for investigating mineral-catalyzed chemical reactions relevant to the origins of life. “We’re increasingly focused on understanding how simpler geochemicals and the myriad of organic compounds delivered to Earth via meteorites during the Late Heavy Bombardment period of Earth’s early history might have assembled to form the more complex molecules of life under high-pressure conditions, such as those found in hydrothermal vent systems and in deep underground environments.”
Gaylor’s lab also develops supercritical fluids methods for a number other research areas:
- Extracting/characterizing beneficial and pollutant chemicals associated with South Dakota’s alternative energy and deep underground research efforts
- Extracting/characterizing anthropogenic chemicals in environmental samples, (e.g. land-applied sewage sludge biosolids)
- Assessing the phytochemical inventories of ornamental plant nectars in relation to their capacity to uptake pollutants from indoor air,
- Estimating pollutant bioavailability to soil organisms
- Extracting/purifying bioactive natural product compounds
Supercritical Fluids in an Analytical Chemistry Class: An example
Another past winner of this award is Trinity College in Hartford, Connecticut. Trinity B.S. degree’s in chemistry and biochemistry and encourages student research throughout their college career.
“The acquisition of the Spe-edTM SFE Prime supercritical fluid extraction apparatus has provided our students with the opportunity to explore the fundamental properties of supercritical fluids at the lab bench and to experience firsthand the benefits offered by this important “green” sample preparation technology,” says Professor Janet Morrison.
Prof. Morrison goes on to describe in detail how she was able to successfully incorporate teaching supercritical fluids as a way to get students thinking about greener processes in the lab and in industrial applications. She writes:
“Analytical Chemistry (Chem 311) is a required course for all of our majors and is one of the most challenging classes in the department in terms of both lecture and laboratory demands. In one of the experiments currently performed in this course, students use gas chromatography and the internal standard calibration method to determine the fatty acid composition of a variety of food products, such as potato chips and other snack foods typically consumed by college students. The classical procedure involves isolation of the fat from the food using methylene chloride, followed by saponification, transesterification to fatty acid methyl esters (FAMEs) using BF3-methanol, back extraction into methylene chloride, concentration of the extract, and, finally, quantitative analysis by GC. This conventional sample preparation method is cumbersome and messy, involving several transfers of material and the use of multiple flasks, and is typically the most time-consuming portion of the experiment for the students.
“With the addition of the Spe-edTM SFE Prime instrument, students have compared the classical procedure with a streamlined SFE procedure by extracting the fat from the food samples using SF-CO2 as a “green” solvent-less alternative to the methylene chloride approach. The students compare the conventional method with SFE in terms of solvent usage, extraction time, recovery efficiency, and analysis cost on a per sample basis considering the cost of solvents (purchase and disposal) and time. This side-by-side comparison of the conventional solvent-based method with the SFE method complements and reinforces our lecture discussion of the benefits of supercritical fluids for extraction. The incorporation of SFE into the laboratory portion of the course thus converts what previously was a theoretical lecture discussion into a valuable educational hands-on experience with this alternative sample preparation technology.
“A culminating part of the lab experience in Analytical Chemistry involves student groups proposing independent projects for which they then design and carry out the experiments and analyze, interpret, and present the results. One group chose to further investigate the applicability of SFE for the isolation and subsequent analysis of fatty acids from commercial foods by not only extracting with SF-CO2, but also performing a single flask simultaneous collection and derivatization by bubbling the SF-CO2 effluent directly into BF3-methanol in the collection tube. The collection tube was subsequently heated to facilitate transesterification and the resulting FAMEs were isolated into a small volume of hexane added to the collection tube.
“Because the SFE extraction vessel can be weighed before and after SFE (if extracted to a final constant mass), students can additionally get an estimate of the total fat content of food samples, and we have had students estimate the fat content in chocolate using SFE. To expose more surface area, prior to SFE the chocolate samples are freeze-fractured using a small volume of liquid nitrogen, and then crushed into a fine powder using a mortar and pestle. More advanced concepts can be studied by having the students generate extraction profiles to optimize extraction time and explore extraction kinetics.”
There are many possibilities for using supercritical fluids in your lab! Don’t miss the chance to submit an application for this Educational Grant by April 30, 2018.
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