19 research outputs found
Spaceboard II Structural Panels: Forming Apparatus and Methods
Novel methods and a patented apparatus have been developed to fabricate Spaceboard II, a new unique structural board of pulped wood fiber. Like the earlier Spaceboard I, the board has flat, high-density faces and a core of rectangular cells defined by high-density cell walls formed integrally with the faces. The board is assembled from two asymmetrical panel halves joined cell to cell. The panels are formed (molded) at low bulk density and subsequently compacted to a unique shape and uniform high density. Spaceboard II is formed by the porous mandrel method, which allows fabrication of much thicker panels than was possible with the original Spaceboard I method. A variety of wet or dry (adhesive-coated) fiber furnish may be used, with either air or water as the forming vehicle. The boards are being investigated for use in light frame and commercial construction; for packaging, palletizing, partitions, and furniture; and for other uses. In the present study, a total of 55 panels, 635 by 1,244 by 38 mm thick, were made by wet-and dry-forming methods in a Forest Products Laboratory patented apparatus
Nanofibrillated Cellulose from Appalachian Hardwoods Logging Residues as Template for Antimicrobial Copper
TEMPO nanofibrillated cellulose (TNFC) from two underutilized Appalachian hardwoods, Northern red oak (Quercus rubra) and yellow poplar (Liriodendron tulipifera), was prepared to determine its feasibility to be used as template for antimicrobial metallic copper particles. In addition, a comparison of the TNFC from the two species in terms of their morphological, chemical, thermal, and mechanical properties was also performed. The woody biomass was provided in the form of logging residue from Preston County, West Virginia. A traditional kraft process was used to produce the pulp followed by a five-stage bleaching. Bleached pulps were then subjected to a TEMPO oxidation process using the TEMPO/NaBr/NaClO system to facilitate the final mechanical fibrillation process and surface incorporation of metallic copper. The final TNFC diameters for red oak and yellow poplar presented similar dimensions, 3.8±0.74 nm and 3.6±0.85 nm, respectively. The TNFC films fabricated from both species exhibited no statistical differences in both Young’s modulus and the final strength properties. Likely, after the TEMPO oxidation process both species exhibited similar carboxyl group content, of approximately 0.8 mmol/g, and both species demonstrated excellent capability to incorporate antimicrobial copper on their surfaces
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Robust enzymatic saccharification of a Douglas-fir forest harvest residue by SPORL
Forest harvest residues can be a cost-effective feedstock for a biorefinery, but the high
lignin content of forest residues is a major barrier for enzymatic sugar production. Sulfite
pretreatment to overcome strong recalcitrance of lignocelluloses (SPORL) was applied to a
Douglas-fir (Pseudotsuga menziesii (Mirb) Franco var. menziesii) forest residue in a range of
sulfite and acid loadings at 165°C for 75 min with liquid to wood ratio of 3:1. Sodium
bisulfite and sulfuric acid charge as mass fraction of oven dry biomass of 12% and 2.21%,
respectively, was optimal in terms of enzymatic cellulose saccharification, sugar yield and
formation of hydroxymethylfurfural (HMF) and furfural. Enzymatic glucose yield was
345 g kg⁻¹, or equivalent to 82.3% of theoretical at a cellulase (CTec2) dosage of 15 filter
paper unit (FPU) per gram of glucan. HMF and furfural formation were low at approximately
2.5 g L⁻¹ each in the pretreatment hydrolyzate. Delignification was important to
achieve good cellulose saccharification efficiency, however, approximately 80-90% hemicellulose
removal is also required. Substrate enzymatic digestibility (SED) was found to
correlate to a combined parameter Z(CHF) of delignification and hemicellulose dissolution
well, suggesting that the combined hydrolysis factor (CHF) - a pretreatment severity
measure - can be used to predict saccharification of forest residue for scale-up studies to
reduce numbers of experiments.Keywords: Forest harvest residue, Pretreatment, Biofuel, Enzymatic hydrolysis/saccharification, Pretreatment severit
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Case studies on sugar production from underutilized woody biomass using sulfite chemistry
We examined two case studies to demonstrate the advantages of sulfite chemistry for pretreating underutilized woody biomass to produce sugars through enzymatic saccharification. In the first case study, we evaluated knot rejects from a magnesium-based sulfite mill for direct enzymatic sugar production. We found that the sulfite mill rejects are an excellent feedstock for sugar production. In the second study, we presented SPORL (sulfite pretreatment to overcome the recalcitrance of lignocelluloses), a sulfite pretreatment process based on modified sulfite pulping for robust bioconversion of softwood forest residues. Sulfite pulping technology is well developed, with proven commercial scalability, and sulfite pretreatment is a strong contender for commercial adoption. Application: Mills can consider sulfite chemistry, which has the advantage of high-yield sugar production from woody biomass through enzymatic saccharification.This is the publisher’s final pdf. The published article is copyrighted by Tappi Press and can be found at: http://www.tappi.org/tappijourna
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Using sulfite chemistry for robust bioconversion of Douglas-fir forest residue to bioethanol at high titer and lignosulfonate: A pilot-scale evaluation
This study demonstrated at the pilot-scale (50 kg) use of Douglas-fir forest harvest residue, an underutilized
forest biomass, for the production of high titer and high yield bioethanol using sulfite chemistry
without solid–liquor separation and detoxification. Sulfite Pretreatment to Overcome the Recalcitrance
of Lignocelluloses (SPORL) was directly applied to the ground forest harvest residue with no further
mechanical size reduction, at a low temperature of 145°C and calcium bisulfite or total SO₂ loadings
of only 6.5 or 6.6 wt% on oven dry forest residue, respectively. The low temperature pretreatment facilitated
high solids fermentation of the un-detoxified pretreated whole slurry. An ethanol yield of 282 L/tonne, equivalent to 70% theoretical, with a titer of 42 g/L was achieved. SPORL solubilized approximately
45% of the wood lignin as directly marketable lignosulfonate with properties equivalent to or better than
a commercial lignosulfonate, important to improve the economics of biofuel production.Keywords: High titer biofuel, Lignosulfonate, Pretreatment, Forest residues, Sulfite pulpin
Nanofibrillated Cellulose From Appalachian Hardwoods Logging Residues As Template For Antimicrobial Copper
TEMPO nanofibrillated cellulose (TNFC) from two underutilized Appalachian hardwoods, Northern red oak (Quercus rubra) and yellow poplar (Liriodendron tulipifera), was prepared to determine its feasibility to be used as template for antimicrobial metallic copper particles. In addition, a comparison of the TNFC from the two species in terms of their morphological, chemical, thermal, and mechanical properties was also performed. The woody biomass was provided in the form of logging residue from Preston County, West Virginia. A traditional kraft process was used to produce the pulp followed by a five-stage bleaching. Bleached pulps were then subjected to a TEMPO oxidation process using the TEMPO/NaBr/NaClO system to facilitate the final mechanical fibrillation process and surface incorporation of metallic copper. The final TNFC diameters for red oak and yellow poplar presented similar dimensions, nm and nm, respectively. The TNFC films fabricated from both species exhibited no statistical differences in both Young’s modulus and the final strength properties. Likely, after the TEMPO oxidation process both species exhibited similar carboxyl group content, of approximately 0.8 mmol/g, and both species demonstrated excellent capability to incorporate antimicrobial copper on their surfaces
Lignin Based Activated Carbon Using H3PO4 Activation
Activated carbon (AC) with a very high surface area of over 2000 m2/g was produced from low sulfur acid hydrotropic lignin (AHL) from poplar wood using H3PO4 at a moderate temperature of 450 °C (AHL-AC6). ACs with similar surface areas were also obtained under the same activation condition from commercial hardwood alkali lignin and lignosulfonate. Initial evaluation of AC performance was carried out using nitrogen adsorption-desorption and dye adsorption. AHL-AC6 exhibited the best specific surface area and dye adsorption performance. Furthermore, the adsorption results of congo red (CR) and methylene blue (MB) showed AHL-AC6 had greater adsorption capacity than those reported in literature. The dye adsorption data fit to the Langmuir model well. The fitting parameter suggests the adsorption is nearly strong and near irreversible, especially for MB. The present study for the first time provided a procedure for producing AC from lignin with Brunauer–Emmett–Teller (BET) surface area >2000 m2/g using low cost and low environmental impact H3PO4 at moderate temperatures
SPORL Pretreatment Spent Liquors Enhance the Enzymatic Hydrolysis of Cellulose and Ethanol Production from Glucose
This study investigated
the recycle utilization of SPORL pretreatment
spent liquor. Three lignosulfonates (LSs) were purified from the spent
liquor of SPORL pretreated Beetle-killed lodgepole pine (BKLP), Poplar
NE222 (NE222), and Douglas-fir (FS10). The structural characterization
showed that the apparent molecular mass and sulfur content of NE222-LS
were lowest, but the phenolic group content was highest. FS10-LS,
from a pH profiling SPORL pretreatment, had the highest apparent molecular
mass but medium sulfur and phenolic group content. The spectral analyses
exhibited that the guaiacyl unit was the main structure in BKLP and
FS10 LSs, while NE222-LS mainly contained both guaiacyl and syringyl
units. Both LSs and SPORL pretreatment spent liquors were used as
additives to enzymatic hydrolysis of Whatman paper and ethanol production
from glucose. LSs and liquors, from SPORL pretreated BKLP and NE222,
could obviously enhance the enzymatic saccharification. Nevertheless,
LS and liquor from SPORL pretreated FS10 presented a slight negative
effect on enzymatic saccharification. All LSs and liquors with low
concentration exhibited no inhibition on ethanol fermentation from
glucose. When whole spent liquors without any detoxification were
applied to prepare the fermentation medium with an initial glucose
concentration of 100 g/L, the ethanol yield was almost the same as
the control for BKLP and FS10 liquors. Nevertheless, the whole NE222
liquor without detoxification inhibited ethanol production thoroughly
MILL DEMONSTRATION OF TMP PRODUCTION FROM FOREST THINNINGS: PULP QUALITY, REFINING ENERGY, AND HANDSHEET PROPERTIES
High-value, large-volume utilization of forest thinning materials from U.S. National Forests is a potentially important contributor to sustainable forest health. This study demonstrated the utilization of wood chips produced from thinnings for the production of thermomechanical pulp (TMP). Both whole-log chips (primarily from small-diameter logs, tops, and reject logs) and sawmill “residue” chips from a HewsawTM system (Mäntyharju, Finland) were evaluated. The residue chips produced in this study were substituted for a TMP mill’s standard residue chips up to about 50%. The whole-log chips were substituted for the mill’s whole-log chips up to about 30%. The results show that substitution of chips produced from forest thinnings reduced refining energy in all trials. Pulp quality was maintained throughout all trials
Production of 1,000 Gallons of Biojet in the NARA Consortium
This report describes the steps and conditions used to produce 1,000 gallons of biojet fuel made from forest residuals