Biomass Deconstruction and Pretreatment Publications

2016

Improving Sugar Yields and Reducing Enzyme Loadings in the Deacetylation and Mechanical Refining (DMR) Process through Multistage Disk and Szego Refining and Corresponding Techno-Economic Analysis, ACS Sustainable Chemistry & Engineering

Eight black-and-white micrograph images of corn stover

2015

Techno-Economic Analysis of the Deacetylation and Disk Refining Process: Characterizing the Effect of Refining Energy and Enzyme Usage on Minimum Sugar Selling Price and Minimum Ethanol Selling Price, Biotechnology for Biofuels

An image of a schematic flow diagram of deacetylation and disk refining process of corn stover: 1) the Decetylation Step includes the "atmospheric deacetylation tank," where "3/4-inch milled corn stover" is put to remove acetate; 2) then it goes to the "Press;" 3) next is the "Disc Refining Step," which includes a "Mechanical Refiner (Atmospheric); 4) then it travels to a "Paddle Reactor (High Solids Enzymatic Hydrolysis)" followed by a "Fermenter," which produces "Fuels and Chemicals" or "Lignin for Upgrading to Fuels and Chemicals." After the "Press," the image also shows the option of producing "Alkaline Spent Liquor for Recycling or Water Treatmen" or "low molecular weight lignin and acetate."

Biomass-Derived Lignin to Jet Fuel Range Hydrocarbons via Aqueous Phase Hydrodeoxygenation, Green Chemistry

Image of a diagram with a curved line extending from "Lignin" to "Degradation" and an arrow pointing to "Monomers," from which another curved line extends to "Coupling HDO," with an arrow pointing at "Cyclic structure hydrocarbons. Another curved line extends from "Lignin" to "Degradation" with an arrow pointing to "Dimers" with two arrows: one pointing to "Degradation" and then to "Monomers; and the other to "HDO" pointing to "Cyclic structure hydrocarbons"

Pilot-Scale Batch Alkaline Pretreatment of Corn Stover, ACS Sustainable Chemistry & Engineering

Image of a diagram corn stover pretreatment showing arrows pointing from "Corn Stover," "NaOH/H2O," and "AQ" to a rectangle; and on the other side of the rectangle is an arrow pointing from "Jacket Steam Injection." The rectangle has an arrow pointing to an image of a "55-gallon drum" and an image representing liquid called "Pretreatment slurry in suspended mesh basket" and another image of liquid called "Pretreatment liquor separated from slurry; and then theres another schematic line from the rectangle to "TD" and an arrow pointing to "Condensate Drain."

Controlling Porosity in Lignin-Derived Nanoporous Carbon for Supercapacitor Applications, ChemSusChem

Image of a green cover for a journal called "Chemistry and Sustainability""CHEMSUSCHEM" entitled "Energy and Materials; 3/2015" and an image of car on a road and a sign that says "Renewable Energy Storage."

Multiphysics Modeling and Simulation of High-Solids Dilute-Acid Pretreatment of Corn Stover in a Steam-Explosion Reactor, Chemical Engineering Journal

$Image of six charts showing experimentally measured and simulation-derived quantities after different times of pretreatment for the base-case conditions of 150C steam and 1% acid: (a) mass fraction of xylan in the biomass solids, (b) amount of water added per gram of initial liquid, (c) mass fraction of insoluble solids in the slurry; soluble species concentrations (d) xylose, (e) xylooligomers, and (f) furfural. The bars show the magnitude of the deviation of the xylan-species mass balance (a) and solids mass balance (c) from unity, and hence the bars provide a quantitative indication of data uncertainty.$

Transgenic Ferritin Overproduction Enhances Thermochemical Pretreatments in Arabidopsis, Biomass & Bioenergy

An image showing the construct for intracellular expression of soybean ferritin in Arabidopsis. (A) Mature soybean ferritin H-1 (Sfer H-1), which was used for gene synthesis. EP: extension peptide; ABCD and E, 5 helices. (B) Expression construct showing ferritin gene replacing the catalase intron-GusPlus gene cassette in the vector of pCAMBIA1305.1 (www.cambia.org/). The ferritin gene expression was under the control of cauliflower mosaic virus 35S promoter (CAMV35S prom), a strong and constitutive promoter, and the terminator was nopaline synthase (nos) polyA.

2014

A Highly Efficient Dilute Alkali Deacetylation and Mechanical (Disc) Refining Process for the Conversion of Renewable Biomass to Lower Cost Sugars, Biotechnology for Biofuels

Image of a chart showing the yield of monomeric glucose and xylose from low solids enzymatic hydrolysis of DCS and DRDCS. The digestions were carried out at 1% (w/w) cellulose loadings with an enzyme loading of 32 mg/g cellulose CTec3 and 5 mg/g cellulose HTec3.

Noble-Metal Catalyzed Hydrodeoxygenation of Biomass-Derived Lignin to Aromatic Hydrocarbons, Green Chemistry

An image of a diagram showing the "Lignin Deconstruction Process:" 1) "Lignin Recovery" and "Selective Hydrolysis;" 2) "Reactive Lignin Oligomers;" 3) "Multifunctional Catalytic System""Depolymerization (Reactive Lignin Intermediares)," "Hydrogenolysis (Oxygenated Aromatics)," and "Hydrocoxygenation;" and 4) "Hydrocarbons (Cyclic Alliphatics and Aromatics) with an arrow pointing to an image representing deconstructed lignin cellular structure

Effect of Mechanical Disruption on the Effectiveness of Three Reactors Used for Dilute Acid Pretreatment of Corn Stover Part 1: Chemical and Physical Substrate Analysis, Biotechnology for Biofuels

Image of schematic diagrams of the three reactors: (A) ZipperClave (ZC), (B) steam gun (SG), and (C) horizontal screw (HS) reactors.

Effect of Mechanical Disruption on the Effectiveness of Three Reactors Used for Dilute Acid Pretreatment of Corn Stover Part 2: Morphological and Structural Substrate Analysis, Biotechnology for Biofuels

Image of CSLM micrographs show cellular-scale evidence of biomass deconstruction. (a) Control, (b) ZC, (c) SG, and (d) HS. The ZC samples have generally thicker cell walls with only limited evidence of delamination and disruptions (b). The SG samples display extensive dislocation of individual cells indicating that the middle lamella layers have been removed and the cells have been forced apart (c, arrow). The HS reactor samples also exhibit extensive dislocation, but in addition display cell wall delamination and fragmentation. Bar=50 m. CSLM, confocal scanning laser microscopy; HS, horizontal screw; SG, steam gun; ZC, ZipperClave.

Multiscale Deconstruction of Molecular Architecture in Corn Stover, Nature

Image of (A) USAXS patterns (left-to-right), untreated; DA-pretreated; DA/Fe-pretreated. (B) WAXS patterns (left-to-right), untreated; DA-pretreated; DA/Fe-pretreated samples. (C) WAXS pattern from a sample exhibiting sharp SAXS reflections observed from very small (greater than 5 micron 3) scattering volumes of untreated material. Insets show an enlargement of the small angle region (top) and a high-pass filtered version to enhance their visualization (bottom).

Characterization of Pilot-Scale Dilute Acid Pretreatment Performance Using Deacetylated Corn Stover, Biotechnology for Biofuels

Image of block flow diagram of the deacetylation, impregnation and pretreatment processes. It shows Corn Stover and Sodium Chloride (where water is added) going through Deacetylation, with spent caustic liquor. The substance then goes through acid impregnation, where H2SO4 is added; and then through Solid Separation, with acid liquor removed, before going through Pretreatment, where steam is added. Pretreatment releases pretreatment reactor vent stream and pretreated corn stover slurry, and the substance then moves to the final process: Flash, which results in flash vent stream.

2013

Comparison of Different Mechanical Refining Technologies on the Enzymatic Digestibility of Low Severity Acid Pretreated Corn Stover, Bioresource Technology

Image of four charts showing volume wt-% versus particle size distribution before and after mechanical refining. Corn stover (Pioneer variety 33A14) pretreated in the NREL Digester at 150 C, 0.5 wt% H2SO4, 15 min was mechanically refined by a PFI mill (Panel a), a twin screw extruder (Panel b), a food processor blender (Panel c), and a 12-inch disk refiner (Panel d).

3-D Electron Tomography of Pretreated Biomass Informs Atomic Modeling of Cellulose Microfibrils, ACS Nano

Image showing six images: a microscopic image, a bar chart showing the average curvature of something (doesnt say of what); another image showing the radius of a circle and the calculation of rk; a 3-D chart image (doesnt say what it shows); a red image showing cellular structure, labeled "original coordinates;" and a blue and green cellular structure image labeled, "Energy-minimized coordinates."

2012

The Impacts of Deacetylation prior to Dilute Acid Pretreatment on the Bioethanol Process, Biotechnology for Biofuels

Image of a table showing the acetyl-to-xylose molar ratio in the solids before pretreatment, in the residual solids after pretreatment, and in the residual solids after enzymatic hydrolysis for native and deacetylated corn stover feedstocks.

Improved Ethanol Yield and Reduced Minimum Ethanol Selling Price (MESP) by Modifying Low Severity Dilute Acid Pretreatment with Deacetylation and Mechanical Refining: 1) Experimental, Biotechnology for Biofuels

Image of a chart showing the effect of deacetylation and mechanical refining on fermentation yield; "blue square symbol"control; "red square symbol" deacetylated; GU: glucose utilization; XU: xylose utilization; EY: ethanol yield.

Improved Ethanol Yield and Reduced Minimum Ethanol Selling Price (MESP) by Modifying Low Severity Dilute Acid Pretreatment with Deacetylation and Mechanical Refining: 2) Techno-Economic Analysis, Biotechnology for Biofuels

Image of a bar chart showing MESP comparison of whole slurry and washed solids cases. (blue bar) Control; (red bar) Control+wash; (green bar) Deacetylation; (violet bar) Deacetylation+wash; (acqua blue bar) Refining; (orange bar) Refining+wash; (sky blue bar) Deacetylation+refining; (pink bar) Deacetylation+refining+wash.

2011

Improved Xylan Hydrolysis of Corn Stover by Deacetylation with High Solids Dilute Acid Pretreatment, Industrial & Engineering Chemistry Research

Image of a chart showing solubilization of acetate vs xylose for native and deacetylated corn stover

Surface and Ultrastructural Characterization of Raw and Pretreated Switchgrass, Bioresource Technology

Image of four microscopic images showing: Stereo (A), SEM (B), and TEM (C, D) micrographs highlighting aspects of green harvested Shawnee switchgrass. Many of the native, milled switchgrass particles were green (A). Residual, partly desiccated plant cells can be visualized within the cell lumen by SEM and TEM (BD arrows). CL, cell lumen; ML, middle lamella. Scale bars = 1 mm (A), 100 m (B), 10 m (C), 2 m (D).

Process and Technoeconomic Analysis of Leading Pretreatment Technologies for Lignocellulosic Ethanol Production Using Switchgrass, Bioresource Technology

Image of a bar chart showing MESP sensitivity studies for AFEX, LHW and SAA pretreatments.

2010

Heat and Mass Transport in Processing of Lignocellulosic Biomass for Fuels and Chemicals, Sustainable Biotechnology