External Links of Interest
External Links of Interest
Green Chemistry is defined as "the use of a set of principles that reduces or eliminates the use or generation of hazardous substances in the design, manufacture, and application of chemical products."1 It's kind of Hippocratic Oath for chemists, a thought process for practicing chemists, and a link to the goals of sustainability.
Green Chemistry and our expertise with supercritical fluid technology provide the basis for our research program. At elevated temperatures and pressures (i.e., above the critical point) compounds become supercritical fluids and possess properties intermediate between gases and liquids. These fluids dissolve solutes, yet have gas-like diffusivity and surface tension. Importantly, these properties can be varied as a function of temperature and pressure. Resulting chemical processes in supercritical fluids can have advantages of being faster and more selective, with minimal use of hazardous organic solvents.
Specifically, our research falls into three major areas: analytical separations, bioprocessing, and green chemistry education.Analytical Separations. Virtually all laboratory samples require some type of separation prior to analysis. We are interested in analytical sample preparation (i.e., extraction) and high resolution chromatography methods. In the extraction area, we use supercritical fluid extraction (SFE) and a related technique, accelerated solvent extraction, for the isolation of selected organic compounds from a variety of sample types. Areas of active interest include studies on the role of diffusion in the extraction of solid samples, the isolation of additives (antimicrobials and growth hormone) from animal feeds and tissues, and the determination of chemical contaminants that may migrate into foods during cooking. Another project is exploring the use of green solvents and chelating agents in separation processes. Our interests in high-resolution chromatography are in the use of supercritical fluid chromatography and high-temperature liquid chromatography for the characterization of complex samples.Bioprocessing. The next generation of biofuels includes cellulosic ethanol, but first the lignin sheath that surrounds the cellulose fibers must be isolated from the carbohydrate components. We are exploring the use of supercritical fluids, microwave irradiation, and ionic liquids for the fractionation and hydrolysis of native grasses, distillers dried grain with solubles (DDGS), and soybeans. A major effort has just been initiated to use ionic liquids in the pyrolysis of prairie cordgrass into military jet fuel. We have used SFE to isolate a biodegradable polymer from the fermentation of DDGC. Finally, supercritical carbon dioxide is being utilized in refining beeswax and tanning leather.
Green Chemistry Education
We have created a set of metrics to compare the green attributes of analytical methods and are applying this to analytical experiments. Educational materials for both the secondary and post-secondary level are being developed and we are investigating student attitudes toward social responsibility following exposure to green chemistry in the classroom.
1P. T. Anastas and J. C. Warner, "Green Chemistry: Theory and Practice," Oxford Press, 1998.
L. N. Tenlep, N. S. Thiex, and D. E. Raynie, "Compositional Analysis of Chemically Pretreated Biomass Samples," J. ASTM International (in press).
J. L. Driver, N. S. Thiex, D. E. Raynie, M. Ofitserova, and M. Pickering, "Single-Laboratory Validation for the Quantification of Neomycin B and Neomycin C in Animal Feeds by Liquid Chromatography-Fluorescence Detection with Post-Column Derivatization," J. AOAC Intl. 92, 34-41 (2009).
D. E. Raynie, "Modern Extraction Techniques," Anal. Chem. 78, 3997-4004 (2006). J. L. Driver and D. E. Raynie, "Method Development for Biomolecules," in HPLC Method Development of Pharmaceuticals, S. Ahuja and H. Rasmussen (editors), Elsevier, New York, pp. 425-440 (2007).
A. H. Ullman and D. E. Raynie, "Problem Solving and Guidelines for Method Selection" in Comprehensive Analytical Chemistry, 47, 799-848, S. Ahuja and N. Jespersen (editors) (2006).
A. Dupay, N. Thiex, D. Ferris, and D. E. Raynie, "Method Development for the Determination of Neomycin in Animal Feed," Proc. S. D. Acad. Sci. 83, 269 (2004). D. E. Raynie, "Modern Extraction Techniques," Anal. Chem. 76, 4659-4664 (2004).
D. E. Raynie, "A Fundamental Understanding of the Chemical Extraction Process," Encyclopedia of Separation Science, I. D. Wilson, T. R. Adlard, C. F. Poole, and M. Cooke (eds.), Academic Press (2000).
T. L. Chester, J. D. Pinkston, and D. E. Raynie, "Supercritical Fluid Chromatography," Anal. Chem. 70, 301R-319R (1998).
D. E. Raynie, "Meeting the Natural Products Challenge with Supercritical Fluids," ACS Symp. Ser. 670, 68-75 (1997).
T. L. Chester, J. D. Pinkston, and D. E. Raynie, "Supercritical Fluid Chromatogaphy and Extraction," Anal. Chem. 68, 487R-514R (1996).
T. L. Chester, J. D. Pinkston, and D. E. Raynie, "Supercritical Fluid Chromatography and Extraction," Anal. Chem. 66, 106R-130R (1994).
D. E. Raynie and T. E. Delaney, "Effect of Entrained Helium on the Kinetics of Supercritical Fluid Extraction with Carbon Dioxide," J. Chromatogr. Sci. 32, 298-300 (1994).
D. E. Raynie, "Warning Concerning the Use of Nitrous Oxide in Supercritical Fluid Extractions," Anal. Chem. 65, 3127-3128 (1993).
D. E. Raynie, K. M. Payne, K. E. Markides, and M. L. Lee, "Evaluation of Microbore and Packed Capillary Column Chromatography with an Ethylvinylbenzene-Divinylbezene Polymeric Packing Material and Supercritical Ammonia as the Mobile Phase," J. Chromatogr. 638, 75-83 (1993).
H. Liu, L. M. Cooper, D. E. Raynie, J. D. Pinkston, and K. R. Wehmeyer, "Combined Supercritical Fluid Extraction/Solid-Phase Extraction with Octadecylsilane Cartridges as a Sample Preparation Technique for the Ultratrace Analysis of a Drug Metabolite in Plasma," Anal. Chem. 64, 802-806 (1992).
T. L. Chester, J. D. Pinkston, and D. E. Raynie, "Supercritical Fluid Chromatography and Extraction," Anal. Chem. 64, 153R-170R (1992).
D. E. Raynie, D. R. Nelson, and K. T. Harper, "Alkaloidal Relationships in the Genus Arctomecon (Papaveraceae) and Herbivory in A. humilis," Great Basin Natural. 51, 397-403 (1991).
D. E. Raynie, K. E. Markides, and M. L. Lee, "Boiling Range Distribution of Petroleum and Coal-Derived Heavy Ends by Supercritical Fluid Chromatography," J. Microcol. Sep. 3, 423-433 (1991).
S. H. Page, D. E. Raynie, S. R. Goates, M. L. Lee, D. J. Dixon, and K. P. Johnston, "Predictability and Effect of Phase Behavior of CO2/Propylene Carbonate in Supercritical Fluid Chromatography," J. Microcol. Sep. 3, 355-369 (1991).
D. E. Raynie, M. L. Lee, D. R. Nelson, K. T. Harper, E. W. Mead, and F. R. Stermitz, "Alkaloids of Arctomecon spp. (Papaveraceae). 12-Methoxyallocryptopine, a New Protopine-type Alkaloid," Biochem. Syst. Ecol. 18, 45-48 (1990).
D. E. Raynie, "In Praise of Microcolumn Abstracts," J. Microcol. Sep. 2, 264-265 (1990).
D. E. Raynie, "Definition and Description of Supercritical Fluid Chromatography," "Historical Development of SFC," "Fluorescence Detection," "Variable Restriction for Flow Control," and "Preparation of Mixed Mobile Phases," Analytical Supercritical Fluid Chromatography and Extraction, M. L. Lee and K. E. Markides (eds.), Brigham Young University Press (1990).
D. E. Raynie, K. E. Markides, M. L. Lee, and S. R. Goates, "Back-Pressure Regulated Restrictor for Flow Control in Capillary Supercritical Fluid Chromatography," Anal. Chem. 61, 1178-1181 (1989).
D. E. Raynie, S. M. Fields, N. M. Djordjevic, K. E. Markides, and M. L. Lee, "A Method for the Preparation of Binary Mobile Phase Mixtures for Capillary Supercritical Fluid Chromatography," J. High Resolut. Chromatogr. 12, 51-52 and 409 (1989).
D. E. Raynie, S. A. Farnum, and Y. R. Potts, "Gas Chromatographic Techniques for the Analysis of Hydrocarbons in Low-Rank Coal Liquefaction Products. Part II. Instrumental Aspects." Proc. N. D. Acad. Sci. 38, 70 (1984).
Y. R. Potts, S. A. Farnum, and D. E. Raynie, "Gas Chromatographic Techniques for the Analysis of Hydrocarbons in Low-Rank Coal Liquefaction Products. Part I. Data Treatment." Proc. N. D. Acad. Sci. 38, 69 (1984).