A5034291395- Biofuel production and bioconversion
- Microbial Metabolic Engineering and Bioproduction
- Catalysis for Biomass Conversion
- Granular flow and fluidized beds
- Enzyme Catalysis and Immobilization
- Rheology and Fluid Dynamics Studies
- Thermochemical Biomass Conversion Processes
- Fluid Dynamics and Mixing
- Advanced Cellulose Research Studies
- Water Systems and Optimization
- Fuel Cells and Related Materials
- Enzyme Production and Characterization
- Mineral Processing and Grinding
- Material Dynamics and Properties
- Lignin and Wood Chemistry
- Agricultural Engineering and Mechanization
- Smart Grid Energy Management
- Minerals Flotation and Separation Techniques
- Anaerobic Digestion and Biogas Production
- Advanced Control Systems Optimization
- Soil Mechanics and Vehicle Dynamics
- Coal Combustion and Slurry Processing
- Protein purification and stability
- Nanopore and Nanochannel Transport Studies
- Carbon Nanotubes in Composites
National Renewable Energy Laboratory
2015-2024
Native American Technologies (United States)
2015
University of California, Davis
2003-2007
Biogen (United States)
2001
Rensselaer Polytechnic Institute
1999
▪ Abstract We review the fluid mechanics and rheology of dense suspensions, emphasizing investigations microstructure total stress. “Dense” or “highly concentrated” suspensions are those in which average particle separation distance is less than radius. For these multiple-body interactions as well two-body lubrication play a significant role non-Newtonian. include multimodal but not with dominant nonhydrodynamic interactions. consider results from both physical experiments computer...
Abstract Effective and efficient breakdown of lignocellulosic biomass remains a primary barrier for its use as feedstock renewable transportation fuels. A more detailed understanding the material properties slurries during conversion is needed to design cost‐effective processes. series enzymatic saccharification experiments were performed with dilute acid pretreated corn stover at initial insoluble solids loadings 20% by mass, which concentration particulate rheological property yield stress...
We present a rheological investigation of fuel cell catalyst inks. The effects ink parameters, which include carbon black-support structure, Pt presence on support (Pt–carbon), and ionomer (Nafion) concentration, the microstructure inks were studied using rheometry in combination with ultrasmall-angle X-ray scattering (USAXS) dynamic light (DLS). Dispersions high-surface-area (HSC), or Ketjen black type, demonstrated higher viscosity than Vulcan XC-72 due to both internal porosity more...
Pressure drop across chromatography beds employing soft or semirigid media can be a significant problem in the operation of large-scale preparative columns. The shape aspect ratio (length/diameter) packed bed has effect on column pressure due to wall effects, which result unexpectedly high pressures manufacturing. Two types agarose-based were columns at various ratios, during drop, height, and flow rate carefully monitored. Compression with increasing velocities was observed. An empirical...
Abstract Background Screening new lignocellulosic biomass pretreatments and advanced enzyme systems at process relevant conditions is a key factor in the development of economically viable ethanol. Shake flasks, reaction vessel commonly used for screening enzymatic saccharifications cellulosic biomass, do not provide adequate mixing high-solids concentrations when shaking supplemented with hand mixing. Results We identified roller bottle reactors (RBRs) as laboratory-scale vessels that can...
Abstract A mechanistically based kinetic model for the enzymatic hydrolysis of cellulosic biomass has been developed that incorporates distinct modes action cellulases on insoluble cellulose polymer chains. Cellulose depolymerization by an endoglucanase (endoglucanase I, EG I ) and exoglucanase (cellobiohydrolase CBH is modeled using population‐balance equations, which provide a description evolution polydisperse distribution chain lengths. The substrate assumed to have enzyme‐accessible...
Abstract The projected cost for the enzymatic hydrolysis of cellulosic biomass continues to be a barrier commercial production liquid transportation fuels from renewable feedstocks. Predictive models kinetics reactions will enable an improved understanding current limitations, such as slow‐down overall conversion rate, and may point way more efficient utilization enzymes in order achieve higher yields. A mechanistically based kinetic model cellulose was recently reported Griggs et al. ( 2011...
Constitutive equations for concentrated suspensions that explicitly account the development of anisotropy in microstructure are not generally available, even relatively simple systems hard spheres suspended a Newtonian medium. Here, we use directionally dependent mean-free path length and truncated Cartesian tensor expansion to define second-order structure particles. This captures principal nature microstructure. A semiempirical differential equation is developed tensor, with representation...
Abstract An improved understanding of how particle size distribution relates to enzymatic hydrolysis performance and rheological properties could enable enhanced biochemical conversion lignocellulosic feedstocks. Particle can change as a result either physical or chemical manipulation biomass sample. In this study, we employed image processing techniques measure slurry validated the results by showing that they are comparable those from laser diffraction sieving. changes slurries were...
Demonstration of a novel integrated algal biomass conversion process for fuels and chemicals.
Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Jonathan J. Stickel, Jeffrey S. Knutsen, Matthew W. Liberatore; Response of elastoviscoplastic materials to large amplitude oscillatory shear flow in the parallel-plate cylindrical-Couette geometries. Rheol. 1 November 2013; 57 (6): 1569–1596. https://doi.org/10.1122/1.4820495 Download citation file: Ris...
Abstract BACKGROUND Converting abundant lignocellulosic biomass to sugars as fungible precursors fuels and chemicals has the potential diversify supply chain for those products, but further process improvements are needed achieve economic viability. In current work, intensification of key enzymatic hydrolysis unit operation is demonstrated by means a membrane reactor system that was operated continuously. RESULTS Lignocellulosic (pretreated corn stover) buffered enzyme solution were fed...
Abstract The discharge of granular media from hoppers plays a vital role in many solids handling operations. dynamic flow poly‐disperse nonspherical particles differs markedly mono‐disperse spheres and highlights the need to rigorously account for particle shape effects. multisphere discrete element method (MS‐DEM) was utilized here examine bulk packing fraction, rate, collisional stress tensor, order parameter bi‐disperse sphere‐rod mixture evacuating hopper. A modified form Myers Sellers...