Molecular Processes

The Molecular Processes division consists of Chemical Energy, which is focused on catalysis, and Chemical Separations and Analysis, which is focused on analytical applications. Current projects in the Chemical Energy area include chemical kinetics and reactivity of transition metal complexes, new synthetic routes to inorganic catalytic materials using organometallic precursors and molecular "stepping stones", spectroscopic and kinetic characterization of metal oxide catalysts, spectroscopic and phenomenological studies of catalysts and advanced materials, and organometallic complexes in homogeneous catalysis. Chemical Separations and Analysis projects are in the areas of analytical separations, analytical spectroscopy, lasers in analytical chemistry, chemical analysis at liquid-solid interfaces, and metal hydride batteries.

Chemical Energy - Catalysis Science

A research team at the Ames Laboratory is engaged in a program of research in chemical catalysis, seeking fundamental chemical and engineering insights about selective oxidation, desulfurization, denitrogenation and dehalogenation reactions by iteratively focusing a spectrum of the expertise in the Ames Laboratory on this important area . The reactions include the removal or addition of a heteroatom (O, S, N, Cl, F) by oxidation or hydrogenation, using transition metals, oxides, and complexes as catalysts. Catalysts for this purpose are being prepared, characterized, evaluated, and improved. Studies of the mechanisms, intermediates, and active sites are key components of the effort, and results from these studies will be constantly fed back into the synthetic effort to provide insight for catalyst modification.

NEW TEXT: This FWP combines the two existing catalysis programs at the Ames Laboratory: Hetero-atom Catalysis and Selective and Efficient Catalysis in 3D Controlled Environment. The collaborative research effort is geared toward bringing together the best features of homogeneous and heterogeneous catalysis for developing new catalytic principles. The fundamental studies under the Heteroatom Catalysis FWP will be integrated with the research thrusts of the FWP of the Selective and Efficient Catalysis in 3D Controlled Environment. Novel silica-based, single-site mesoporous catalysts with controlled, nanostructured morphology and surface properties will be prepared. The control of specific chemical properties, spatial distribution, and concen trations of various catalytic functional groups on the pore walls will be achieved. The catalytic activity of these single-site heterogeneous catalysts will be examined. Detailed mechanistic studies of such systems will be carried out in an effort to recognize the key factors that determine selectivity, reactivity and kinetics of both homogeneous and heterogeneous catalytic reactions.

The leading scientists in this endeavor are Robert Angelici, Andreja Bakac, Marek T. Pruski, Victor Lin, Aaron Sadow and Keith Woo.

Separations and Analysis

Nanodomains

The goals of the proposed research are to develop novel instrumentation and methodology for the analysis of phenomena that occur at nanometer length scales and picosecond time scales. The developed instrumentation and methodology will be applied to model systems of interest to the DOE mission, where fundamental insight can be gained with the high spatial and temporal resolution afforded by our developed methods: chemical reac tions in heterogeneous silica supported catalysts; the organization and dynamics of mixed model lipid bilayers and cell membranes; chromatographic interactions; and heterogeneous enzyme reactions. The methods we propose to develop are:

1. High resolution total internal reflection (TIR) Raman microspectroscopy and imaging
2. Sub-diffraction limited imaging, including differential interference contrast (DIC) microscopy, variable-angle evanescent-field (EFM) microscopy, and time-resolved stimulated emission depletion (STED) microscopy
3. Novel single molecule spectroscopies

Principal Investigators: James S. Fritz, R. Samuel Houk, and Edward S. Yeung

Metabolites

We propose to develop mass spectrometric imaging techniques to map metabolite distributions within plant tissues, and eventually among individual plant cells. Such details will ultimately lead to a predictive understanding of the mechanisms that multicellular organisms use to regulate metabolic processes. By studying the diversity of the cuticular waxes, we hope to gain detailed insight into their biosynthesis as a function of genetics, tissue type, development, and environment. A laser beam will be used to interrogate sequentially micrometer areas of a plant by vaporizing the surface contents of the tissue into a time-of-flight (TOF) mass spectrometer. Rastering of the laser beam over the tissue will produce a laterally resolved image of the various substances within different structures of the plant. Repeated vaporization at the same focused point of a plant structure will produce a depth profile of the components. We plan to generate ions directly from the plant tissue by designing novel additives as pseudo-matrixes.

Princilal Investigators: Lee, Yeung

Energy Biosciences

 

Principal Investigators: Nikolau, Yeung, Lee

PCTC

Principal Investigators: Evans, Gordon

Nanorefinery

This research project aims to develop a nanoparticle technology for efficient and economical extraction methods for harvesting suitable chemical compounds, such as triglycerides, neutral lipids, and fatty acids, from microalgae for biodiesel production and single-step conversion to biodiesel.  Our proposal involves the use of nanoparticles to perform the following two stages, with superior efficiency in terms of yield, simplicity of processing and energy consumption.

1. Simple, selective and efficient extraction of fatty acids by recyclable mesoporous nanoparticles possessing large surface areas and volumes and adjustable pore size.

2. One step conversion of the extracted fatty acids into biodiesel by reusable, highly reactive nanoparticle based catalyst (Catilin method).

Principal Investigators: Lin, Kraus, Pruski, Lee