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The growing interest in bamboo fibers for pulp, paper, and board production in the USA necessitates a comprehensive financial viability assessment. This study conducts a detailed technoeconomic analysis (TEA) of bamboo fiber production, primarily for the consumer hygiene tissue market although it is also applicable to other industrial uses. The economic viability of two pulping methods – alkaline peroxide mechanical pulping (APMP) and ammonium bisulfite chemical pulping (ABS) – was explored within three different pulp mill settings to supply pulp to two nonintegrated tissue and towel mills in South Carolina, USA. The target was to produce wet lap bamboo bleached pulp at 50% consistency and 70% ISO brightness. Despite higher initial capital invesment and operating costs, ABS achieved a lower minimum required selling price – USD 544 to 686 per bone dry metric ton (BDt = 1000 BDkg) – in comparison with USD 766 to 899 BDt−1 for APMP. This price advantage is partly due to an additional revenue stream (lignosulfonate byproduct), which not only boosts revenue but also circumvents the need for expensive chemical recovery systems. When compared with traditional kraft pulping, both methods require significantly lower capital investments, with minimum required selling prices (estimated to achieve 16% IRR) below current market rates for extensively used bleached kraft pulps in the USA tissue industry. The economic benefits derive from several factors: the low cost of bamboo as raw material, reduced capital needs for new pulping technologies, lower transportation costs from the pulp mill to tissue and towel manufacturing facilities, and the high market price of bleached kraft pulp. [ABSTRACT FROM AUTHOR]

Bamboo, recognized for its rapid growth, high yield, and fiber performance is prominent in the fiber‐based bioproduct industry. However, the absence of US industrial bamboo plantations for fiber production necessitates reliance on imports or locally manufactured products using imported bamboo fibers, predominantly from China. This study evaluates the economic viability of cultivating bamboo in the Southern US for fiber production, with a case study on hygiene tissue products. The supply‐chain analysis was assessed to calculate bamboo chips' minimum selling price (MSP) at the farm gate for an 8% internal rate of return (IRR). The MSP, influenced primarily by land rental costs, ranges from USD 48 to 55 per bone‐dry metric ton (BDt). Despite an initial establishment cost of ~USD 2 000 ha−1 and profitability by year 5, bamboo is a viable, long‐term fiber alternative. Successful bamboo cultivation in the US could lead to a more sustainable implementation of alternative non‐wood fibers for hygiene tissue applications. [ABSTRACT FROM AUTHOR]

Economic mobility and career success for undergraduate students is enhanced by understanding students' experiences and supports and addressing the barriers they face. This study explores how U.S. undergraduate transfer students described their career journeys and how they perceived contextual barriers and supports for their career-oriented experiences. This longitudinal narrative case study was conducted with undergraduate students who were transferring from a community college to a four-year college. They participated in a professional development program, which funded science/engineering internships within bioproducts and bioenergy sectors. The study drew from social cognitive career theory and analyzed data collected over two years, including student interviews, biographical mapping, and reflective writings. Students most frequently described supports they received from their professors and program staff (institutional), family (social), and their internship hosts. The barriers they identified were more variable, such as inadequate advising and communication issues, and were often resolved by program staff (institutional) and financial supports from the program and internship sites. Internship participation led to all of the participating students feeling a sense of job readiness. Programmatic supports, such as clear communication between the internship host and the academic program, funding the internships, and addressing barriers by providing adequate mentoring and logistical supports, were found to enhance the experiences of science and engineering transfer students. [ABSTRACT FROM AUTHOR]

Static life cycle assessment (LCA) methodologies fail to consider the temporal profiles of system inputs and outputs (including emission timing), such that they underestimate the benefits of temporarily stored biogenic carbon in bioproducts, such as cotton. This research focuses on greenhouse gas emission timing and applies dynamic emission accounting to the life cycle of cotton woven pants. The significance of temporary biogenic carbon storage and emission timing is illustrated by converting the 2017 Cotton Incorporated static LCA to a dynamic model using the Dynamic Carbon Footprinter (baseline scenario). A reduction in cumulative radiative forcing for dynamic relative to static modeling of 22%, 5%, and 2% are observed at 10-years, 30-years, and 100-years, respectively. Alternative scenarios analyzed include converting cotton woven pants at end of life to bioenergy, to compost, or to building insulation, an alternative cotton production scenario using regenerative agricultural practices, and two pants extended lifetime scenarios. The regenerative agricultural practice scenario provides reductions in cumulative impacts compared to the baseline scenario of 96%, 69%, and 105% after 10, 30, and 100-years, respectively. A 3x extension in the lifetime of pants provides a benefit in reduced cumulative impacts of 31%, 40%, and 41%, after 10, 30, and 100-years, respectively. This case study with cotton demonstrates that dynamic LCA is a useful tool for assessing the benefits of biobased products, and it allows for more nuanced analysis of reductions in climate impacts in both the short- and long-term time horizons. [ABSTRACT FROM AUTHOR]

Plastic pollution is a global environmental threat with potentially irreversible impacts on aquatic life, ecosystems, and human health. This study is a comprehensive assessment of the global apparel industry's contribution to plastic pollution. It includes plastic leakage of packaging and end-of-life apparel waste in addition to fiber emissions during apparel production and use. We estimate that the apparel industry generated 8.3 [4.8–12.3] million tons (Mt) of plastic pollution in 2019, corresponding to 14% [5.5%–30%] of the estimated 60 Mt from all sectors. In this study, we demonstrate that the main source of plastic pollution from the apparel supply chain is synthetic clothing as mismanaged waste either in the country of its original use or in the countries receiving used apparel exports. A fundamental transformation of the apparel economy towards a circular framework and decreased synthetic apparel consumption is needed to tackle apparel-related plastic pollution. Synthetic apparel is a major contributor to global plastic leakage driven by mismanaged apparel waste. [ABSTRACT FROM AUTHOR]

Direct disposal of used soft electronics into the environment can cause severe pollution to the ecosystem due to the inability of most inorganic materials and synthetic polymers to biodegrade. Additionally, the loss of the noble metals that are commonly used in soft electronics leads to a waste of scarce resources. Thus, there is an urgent need to develop "green" and sustainable soft electronics based on eco‐friendly manufacturing that may be recycled or biodegraded after the devices' end of life. Here an approach to fabricating sustainable soft electronics is demonstrated where the expensive functional materials can be recycled and the soft substrate can be biodegradable. A stretchable agarose/glycerol gel film is used as the substrate, and silver nanowires (AgNWs) are printed on the film to fabricate the soft electronic circuits. The mechanical and chemical properties of the agarose/glycerol gel films are characterized, and the functionality of the printed AgNW electrodes for electrophysiological sensors is demonstrated. The demonstration of the biodegradability of the agarose/glycerol and the recyclability of AgNWs points toward ways to develop sustainable and eco‐friendly soft electronics. [ABSTRACT FROM AUTHOR]

Background: The pulp and paper industry (P&PI) is undergoing significant disruption driven by global megatrends that necessitate advanced tools for predicting future behavior and adapting strategies accordingly. Methods: This work utilizes a multi-criteria framework to quantify the effects of digitalization, changes in social behavior, and sustainability as three major megatrends transforming the P&PI industry, with a specific focus on hygiene tissue products. Thus, the research combines a comprehensive literature review, insights from a Delphi study, and topic modeling to qualitatively and quantitatively assess the present and future impacts of these global megatrends. Results: The findings suggest an urgent need to identify alternative raw materials to prevent potential supply chain disruptions. Moreover, due to shifts in social behavior, it becomes critical for businesses to substantiate their sustainability claims with hard data to avoid the risk of a "greenwashing" perception among consumers. Conclusions: This study provides decision support for strategic planning by highlighting actionable insights, quantitative predictions, and trend analysis, alongside the examination of consumer and market trends. It aims to incorporate diverse stakeholder perspectives and criteria into decision-making processes, thereby enriching the strategic planning and sustainability efforts within the P&PI industry. [ABSTRACT FROM AUTHOR]

As the global population grows, the demand for textiles is increasing rapidly. However, this puts immense pressure on manufacturers to produce more fiber. While synthetic fibers can be produced cheaply, they have a negative impact on the environment. On the other hand, fibers from wool, sisal, fique, wood pulp (viscose), and man-made cellulose fibers (MMCFs) from cotton cannot alone meet the growing fiber demand without major stresses on land, water, and existing markets using these materials. With a greater emphasis on transparency and circular economy practices, there is a need to consider natural non-wood alternative sources for MMCFs to supplement other fiber types. However, introducing new feedstocks with different compositions may require different biomass conversion methods. Therefore, based on existing work, this review addresses the technical feasibility of various alternative feedstocks for conversion to textile-grade fibers. First, alternative feedstocks are introduced, and then conventional (dissolving pulp) and emerging (fibrillated cellulose and recycled material) conversion technologies are evaluated to help select the most suitable and promising processes for these emerging alternative sources of cellulose. It is important to note that for alternative feedstocks to be adopted on a meaningful scale, high biomass availability and proximity of conversion facilities are critical factors. In North America, soybean, wheat, rice, sorghum, and sugarcane residues are widely available and most suitable for conventional conversion through various dissolving pulp production methods (prehydrolysis kraft, acid sulfite, soda, SO2 -ethanol-water, and potassium hydroxide) or by emerging cellulose fibrillation methods. While dissolving pulp conversion is well-established, fibrillated cellulose methods could be beneficial from cost, efficiency, and environmental perspectives. Thus, the authors strongly encourage more work in this growing research area. However, conducting thorough cost and sustainability assessments is important to determine the best feedstock and technology combinations. [ABSTRACT FROM AUTHOR]

In this study PLA and PHB were melt-blended with/without maleic anhydride (MA) as a compatibilizer and melt-spun into a monofilament. The aquatic biodegradation of PLA/PHB fibers was tracked regarding the PLA and PHB components and the total carbon in the blend. Pure PLA fiber was recalcitrant to aquatic biodegradation in the present conditions, whereas PHB was readily degradable, as expected. The 75/25% and 50/50% PLA/PHB fibers showed zero biodegradation. The 25/75% PLA/PHB blend showed only an 11% final biodegradation extent and a 13% PHB biodegradation extent. It is shown that an unintended consequence of blending PLA with PHB is that after biodegradation, micro/nano plastic pollution is evolved. MA increased the miscibility, which further decreased the PHB biodegradation. The lower biodegradation extent with MA indicates that increased miscibility and more intimate coverage of the biodegradable polymer with the unbiodegradable polymer may have a negative effect on the biodegradation of biodegradable polymers. [ABSTRACT FROM AUTHOR]

Producing environmentally benign and economically viable nanomaterials is critical for large-scale applications in energy and other industries. This study presents a modeling framework to identify environmentally greener and lower-cost pathways of large-scale nanomaterial production, which encompasses life cycle assessment, Green Chemistry principles, techno-economic analysis, and eco-efficiency analysis. The framework is demonstrated by case studies of cellulose nanomaterials produced in the U.S. For cellulose nanocrystals, the framework identifies pathways that simultaneously reduce the life-cycle global warming potential (GWP) from 17.7 to 2.6 kgCO2e per dry kg cellulose nanocrystals and the minimum selling price (MSP) from US$7540 to US$4587 per dry t cellulose nanocrystals. For cellulose nanofibrils, the strategies present trade-offs of reducing GWP from 7.8 to 0.1 kgCO2e per dry kg cellulose nanofibrils but increasing MSP slightly from US$2873 to US$2985 per dry t cellulose nanofibrils. Eco-efficiency analysis quantifies the magnitudes of co-benefits and trade-offs between the environmental and economic performance of different production strategies and supports decision making for sustainability-informed process optimization. [ABSTRACT FROM AUTHOR]

Microfibers and microplastics originating from wastewater treatment plant (WWTP) effluents are significant pollutants in freshwater sources and marine environments. This research investigated the biodegradation of cotton microfibers generated from bleached cotton jersey knit fabric and commercially available flushable wipes, polypropylene-based (PP) nonwoven wipes containing a cellulose component, and tissue paper. Biodegradation was tested in wastewater treatment plants (WWTP) solids, seawater, and lakewater according to the ISO 14852 and ASTM D6691 standard methods in an ECHO respirometer. Degradation experiments continued until a plateau in CO2 emissions was reached, and the final biodegradation extent was calculated relative to the theoretical CO2 produced based on elemental analysis. The results showed that the cotton and other cellulosic materials/components biodegrade to a great extent, as expected for all conditions, whereas the PP did not degrade. In general, for the cellulose polypropylene composite wipes, the cellulose biodegraded readily; the presence of the PP did not hinder the cellulose biodegradation. [ABSTRACT FROM AUTHOR]

Poly(β-hydroxybutyrate) (PHB) is a well-known biodegradable bio-based polymer but can be brittle. Polymer blending of PHB with polyethylene (PE) or polypropylene (PP) has been proposed to improve the mechanical properties. Compatibilizers have been considered to improve the performance of the polymer blend with PHB; however, the effect of compatibilizers on biodegradation is controversial. In the present study, the PHB polymer was blended with PP, a non-biodegradable synthetic polymer, and spun into fiber form. Furthermore, the effect of increased interaction between the polymers was investigated by increasing the miscibility with compatibilizer, maleic anhydride-grafted polypropylene (MAPP). The biodegradation of PHB in the blends was investigated in aquatic aerobic conditions with a closed respirometer with activated sludge as inoculum. Since PP is not a biodegradable polymer, the PHB-based biodegradation was calculated based on the ratio of oxygen consumption to the theoretical oxygen demand of PHB polymer in the blends. The fibers with a concentration of PHB below 75% showed a significant decrease in PHB biodegradation. This result confirms that non-biodegradable polymers in the blend can hinder the biodegradation of biodegradable polymers. Additionally, this blending is shown herein to have unintended consequences, creating micro and nano pollution of residual synthetic PP material. MAPP has an effect of increasing the miscibility between PP and PHB; however, this increased miscibility rendered the PHB biodegradation to be very low, less than 25%. This result suggests that even though increased miscibility can improve mechanical performance, it can decrease the biodegradation of biodegradable polymers in non-biodegradable/biodegradable polymer blends. [ABSTRACT FROM AUTHOR]

Interdisciplinary collaborations between different academic disciplines can create knowledge and solutions to challenges that are beyond the scope of what a single discipline can achieve. However, little is known about how interdisciplinary teams of faculty and graduate students function as a whole and the processes that guide them as they work on collaborative tasks. Using Activity Theory, this qualitative study analyzed team meeting transcripts to examine interdisciplinary team interactions involving Science/Engineering and Science Education graduate students and faculty members as they co-developed laboratory activities for a grant-funded project. Several factors contributed to the team's success: shared goals (Object), environment (Community), and clear Division of Labor. Differences (contradictions) were found in the Tools, Rules, and Division of Labor; the PI and Science/Engineering graduate students tended to focus on the needed lab materials, and the Science Education members focused more on educational standards and teachers' ideas in the lab development (Tools). The PI and Science Education members set and enforced the team meeting agendas and deadlines (Rules). The Science/Engineering grad students focused on practical considerations to ensure the labs could successfully be implemented in a class setting (Rules) and were assigned the most tasks to complete (Division of Labor). The findings provide insight into the nature of interdisciplinary team dynamics between a Science/Engineering and Education grant team. The findings also suggest the importance of shared goals (Object), community development (Rules: Team Building), and the potential of capitalizing on different strengths and knowledge (contradictions) in an interdisciplinary team. [ABSTRACT FROM AUTHOR]

Significant efforts have been made over the past decade to facilitate the recognition of environmentally friendly packaging and promote sustainability. Yet, consumers remain confused by the excess of labels and claims used to communicate sustainability. In our previous work, we modified the appearance of recycled fibre‐based packaging by incorporating visible particles of fibre‐based waste. This strategy enabled consumers to better identify packages with a high recyclability level, enhancing their environmental perception towards sustainable products. However, the incorporation of such large waste particles proved to be detrimental to the mechanical properties of the paperboards. In this study, we further investigate the influence of the physicochemical properties of the added fibre‐based waste on packaging performance. Using a similar strategy to enhance the environmental perception, we herein studied the effect of mixed office waste (MOW), old magazines (OMG), and polylactic acid (PLA) paper cups. The presence of hydrophobic and difficult‐to‐process and difficult‐to‐disperse waste, such as the PLA paper cups, significantly altered the mechanical performance of the paperboards, whereas more hydrophilic and easy‐to‐disintegrate waste (MOW and OMG) had a lesser effect regardless of the size of the particles. Strength agents such as cationic starch (CS) and cellulose microfibrils (CMFs) successfully restored the properties of the paperboards containing MOW and OMG but were less effective for PLA paper cups. A multi‐ply strategy overcame the limitations of CS and CMFs using the redesigned paperboard as an outer ply for aesthetic purposes and a 100% recycled inner ply for restoring strength. [ABSTRACT FROM AUTHOR]

Under the controversial concern of using virgin fibers in hygiene tissue products, mostly Bleached Eucalyptus Kraft (BEK) and Northern Bleached Softwood Kraft (NBSK), consumers are responding by purchasing selflabeled sustainable products. As of today, there are no established sustainability reported results to inform consumers about the carbon footprint of hygiene tissue. To fill this gap, this study used Life Cycle Assessment to evaluate the environmental impacts across the supply chain (cradle to gate) to produce Premium and Ultra grades of bath tissue, including the production of feedstock, pulp production, and tissue production stages, with focus on Global Warming Potential (GWP). The results showed that one air-dried metric ton (ADmt) of BEK pulp had an associated GWP of 388 kgCO2eq, whereas one ADmt of NBSK pulp presented values ranging between 448 and 596 kgCO2eq, depending on the emissions allocation methodology used. It was estimated that the GWP of one finished metric ton of tissue weighted average could range from 1,392 to 3,075 kgCO2eq depending on mill location, electricity source, and machine technology. These results provide an understanding of the factors affecting the environmental impact of hygiene tissue products, which could guide manufacturers and consumers on decisions that impact their carbon footprint. [ABSTRACT FROM AUTHOR]

Until recently, food packaging has been used as a barrier to unfavorable environmental and microbial conditions, but new technologies are arising aimed at upgrading the protective nature of these materials. Cases of bacterial and viral transmission through food and surfaces have shown the vulnerabilities of the food packaging distribution systems over the years, creating awareness about new methods to prevent the proliferation of pathogens. This has been highlighted by safety concerns due to the COVID‐19 pandemic. This work reviews the state‐of‐the‐art biobased technologies tailored for antiviral applications on surfaces, focusing on packaging materials. A survey and selection tool of essential oils (EOs) and nanoparticles that have been proven effective in reducing the proliferation or transmission of viruses through surfaces is presented. Additionally, the use of essential oil formulations or nanoparticle‐functionalized biobased materials that can be deployed to prevent virus transmission through food produce and surfaces is reviewed, including environmental and safety concerns around the use of metal nanoparticles and EOs in packaging materials. Finally, an assessment of the available technologies, challenges, opportunities and the potential role of biobased antiviral surfaces in future viral outbreaks is presented. [ABSTRACT FROM AUTHOR]

Nonwoven products are widely used in disposable products, such as wipes, diapers, and masks. Microfibers shed from these products in the aquatic and air environment have not been fully described. In the present study, 15 commercial single-use nonwoven products (wipes) and 16 meltblown nonwoven materials produced in a pilot plant were investigated regarding their microfiber generation in aquatic and air environments and compared to selected textile materials and paper tissue materials. Microfibers shed in water were studied using a Launder Ometer equipment (1–65 mg of microfibers per gram material), and microfibers shed in air were evaluated using a dusting testing machine that shakes a piece of the nonwoven back and forth (~ 4 mg of microfibers per gram material). The raw materials and bonding technologies affected the microfiber generation both in water and air conditions. When the commercial nonwovens contained less natural cellulosic fibers, less microfibers were generated. Bonding with hydroentangling and/or double bonding by two different bonding methods could improve the resistance to microfiber generation. Meltblown nonwoven fabrics generated fewer microfibers compared to the other commercial nonwovens studied here, and the manufacturing factors, such as DCD (die-to-collector distance) and air flow rate, affected the tendency of microfiber generation. The results suggest that it is possible to control the tendency of microfiber shedding through the choice of operating parameters during nonwoven manufacturing processes. [ABSTRACT FROM AUTHOR]

Global sustainability megatrends are promoting the utilization of sustainably perceived fibers such as recycled and agricultural residue fibers in hygiene tissue applications. Tissue paper products advertised as sustainable have higher prices and inferior performance than conventional products manufactured from virgin wood fibers. This work demonstrates the feasibility of using agricultural residues from fique plantations (Furcraea microphylla genus) as an alternative to Northern Bleached Softwood Fibers (NBSK) in high-performance hygiene tissue applications. For our study, fiber residues were mechanically cleaned and upgraded to a tissue pulp using a simple pulping and bleaching process. A complete characterization of tissue paper properties (bulk, softness, water absorbency, tensile strength) was performed and compared against the NBSK market pulp. Additionally, fique residue pulp was blended with Bleached Eucalyptus Kraft (BEK) to match the performance of a selected benchmark consisting of 70% BEK and 30% NBSK. Results indicate fique residue bleached pulp has similar fiber morphology and comparable strength properties in terms of the tensile strength (+ 6%) and tear strength (+ 10%), but superior bulk (+ 12%), water absorbency (+ 28%), and softness (−29% TS7 values) than NBSK pulp. A fiber blend of 70% BEK and 30% fique residue showed superior tensile strength (+ 21%), tear strength (+ 54%), bulk (+ 5.5%), water absorbency (+ 1.5%), and softness (−8.7% TS7 values) over a similar fiber blend of BEK and NBSK. Our findings demonstrate that fibers from fique residue can substitute NBSK in hygiene tissue applications. Upgrading residues from fique fibers as raw materials for the tissue industry can bridge the gap between sustainability and product performance, simultaneously opening the possibility of new revenue streams for millions of small farmers in the producing countries. [ABSTRACT FROM AUTHOR]

Sustainable Soft ElectronicsThis cover, referring to article number 2300792 by Orlin D. Velev, Yong Zhu, and co‐workers, illustrates the concept of sustainable soft electronics with biodegradable substrate (agarose/glycerol) and recyclable functional material (silver nanowires). The background represents the molecular structure of the biodegradable substrate with interaction between the agarose polymer helices (blue) and glycerol molecules (red and white). The soft electronic circuit is flexible and stretchable..By Yuxuan Liu; Mesbah Ahmad; Richard A. Venditti; Orlin D. Velev and Yong ZhuReported by Author; Author; Author; Author; Author [Extracted from the article]

Arsenic and other heavy metal contaminants in water are a significant global health threat. In this study, low-cost, sulfur-free, sustainable, water-insoluble materials with heavy metal remediation properties were produced from renewable resources such as starch, xylan, citric acid, and chitosan. Synthesized starch citrate-chitosan (SCC) foam and xylan citrate-chitosan (XCC) foam were flexible, porous, and elastic. The foams' arsenic uptake in water was significantly greater than five different commercial metal remediating agents. The mercury and lead uptakes with the synthesized foams were similar to the performance of a commercial sulfur-based product, SorbaTech 450 (ST450). However, the cadmium and selenium uptakes were comparatively lower. The complexation of arsenic with oxygen and nitrogen of the SCC foam was shown with time-of-flight secondary ion mass spectrometry (TOF-SIMS). The XCC foam was also shown to adsorb potassium iodide (KI) at a similar rate to sodium chloride. This may be used to remediate water contaminated with radioactive materials, such as iodine 131. [ABSTRACT FROM AUTHOR]

Replacing synthetic polymers with renewable alternatives is a critical challenge for the packaging industry. This research investigated the use of leaf‐based proteins as a sustainable co‐binder in the coating formulations for paper‐based packaging and other applications. Protein isolates from tobacco leaf and alfalfa concentrates were characterized using the Pierce protein assay, Kjeldahl nitrogen, and gel electrophoresis. The proteins were tested as co‐binders in a typical latex‐based paper coating formulation. The rheology and water retention properties of the wet coating and the surface, optical, structural, and strength properties of coated papers were measured. The coating performance was affected by the purity, solubility, and molecular weight of the tobacco protein and exhibited a shear‐thinning behavior with lower water retention than soy protein. Analysis by scanning electron microscopy and time of flight secondary ion mass spectroscopy on the dried coating layer containing tobacco protein showed enhanced porosity (advantageous for package glueability) relative to the control latex coating. The tobacco protein offers adequate coverage and coating pigment distribution, indicating that this protein can be a suitable option in coatings for packaging applications. [ABSTRACT FROM AUTHOR]

The importance of renewable and environmentally friendly wood pulp fibers as an input material for single-use products has grown significantly. However, discarded single-use materials are found in the environment as litter and are sometimes disposed of in wastewater. It is important that these materials are biodegradable and environmentally benign. Wood pulp is mainly comprised of lignocellulosic material, and its composition and structure can vary depending on raw materials and processing, ultimately impacting the biodegradability. In this research, the aquatic biodegradation of five kinds of wood pulp and six different samples of isolated lignocellulosic components (cellulose, hemicellulose, and lignin) have been explored in a consistent detailed manner for the first time, and the effects of chemical composition on the biodegradation discussed. Several lignocellulosic materials were characterized using compositional analysis and were subjected to aquatic biodegradation with bio-solids from a wastewater treatment plant as an inoculum to indicate the potential to biodegrade in the environment. Cellulose and hemicellulose were readily biodegraded over a course of one month. The lignin samples were not biodegradable under these conditions, and the lignin within fibers decreased the biodegradability of the other components of the lignocellulosic fibers. It was also determined that ash and extractives negatively affect the biodegradability. The aerobic aquatic biodegradation results are useful for product designers to select different lignocellulosic materials for applications and for environmental scientists to understand the fate of these fibers in the environment. [ABSTRACT FROM AUTHOR]

A better understanding of the drivers of the economic, environmental, and social sustainability of emerging (biobased) technologies and products in early development phases can help decision-makers to identify sustainability hurdles and opportunities. Furthermore, it guides additional research and development efforts and investment decisions, that will, ultimately, lead to more sustainable products and technologies entering a market. To this end, this study developed a novel techno-sustainability assessment (TSA) framework with a demonstration on a biobased chemical application. The integrated TSA compares the potential sustainability performance of different (technology) scenarios and helps to make better-informed decisions by evaluating and trading-off sustainability impacts in one holistic framework. The TSA combines methods for comprehensive indicator selection and integration of technological and country-specific data with environmental, economic, and social data. Multi-criteria decision analysis (MCDA) is used to address data uncertainty and to enable scenario comparison if indicators are expressed in different units. A hierarchical, stochastic outranking approach is followed that compares different weighting schemes and preference structures to check for the robustness of the results. The integrated TSA framework is demonstrated on an application for which the sustainability of a production and harvesting plant of microalgae-based food colorants is assessed. For a set of scenarios that vary with regard to the algae feedstock, production technology, and location, the sustainability performance is quantified and compared, and the underlying reasons for this performance are explored. [ABSTRACT FROM AUTHOR]

In recent years, there have been many advances toward developing sustainable, micro- and nanoscale materials from biobased resources such as lignin aimed at strengthening the bioeconomy. It is critical to study the factors affecting nucleation and growth mechanisms, as well as the stability of lignin micro-and nanoparticles (LPs), to further enhance the development of such materials. However, there remains a gap in the literature examining the many interactions present during and after LP formation. These interactions vary with the chemical composition and molecular weight distribution of different kraft lignin (KL) fractions. To examine the composition of different lignin fractions, KL can be fractionated using water-miscible organic solvents of different polarities such as tetrahydrofuran (THF), acetone, and ethanol. Herein, we show that the micro- and nanoparticles formed from each lignin fraction exhibit significant differences in their size (50–300 nm), particle aggregation and fusion propensity, and spherical morphology in aqueous suspensions. These differences are proposed to be a result of the solvent–lignin–water interactions related to molecular weight and functional groups of the lignin fractions and solvent/water polarity. Another factor affecting the nucleation and growth of LPs is the lignin concentration. The LPs formed at low lignin concentrations exhibit a larger average particle size compared to the LPs formed at higher lignin concentrations due to the aggregation and fusion of the small particles. These results will allow for a stronger foundation in understanding the nucleation and growth of LPs when attempting to develop value-added applications for kraft lignin. [ABSTRACT FROM AUTHOR]

Plasticizers depress the glass transition temperature (Tg) of polymers and produce a flowable material at lower temperatures. The use of plasticizers to depress Tg of lignin is important, since at high processing temperatures lignin crosslinks, making it intractable. The goal of this study was to assess plasticizers and polymer blends for the ability to retard a commercial softwood kraft lignin from crosslinking and also serve as thermal and rheological property modifiers during thermal processing in the attempt to produced moldable and spinnable lignin for lignin and carbon fiber products. The Tg of the lignin and the lignin mixed with various amounts of plasticizers and with different thermo-mechanical mixing were determined using differential scanning calorimetry. The Tg and the change in heat capacity at the glass transition (ΔCp) decreased and increased, respectively, about linearly within this plasticizers range with increased plasticizer weight percentage. Gel permeation chromatography results for extruded lignin as well as extruded lignin-plasticizer blends with glycerol, N-allyurea, citric acid with and without sodium hypophosphite, and oleic acid indicate that the presence of these materials reduced the rate of molecular weight increase at temperatures between 100 and 200 °C. Continuous, homogenous films and fibers could be produced by thermal processing with plasticized lignin samples and plasticized lignin-polymer blends, but not with lignin alone. These fibers could be carbonized, yielding up to about 50% of carbon. The present findings have shown the advantages of plasticizers in thermally processing a commercial softwood kraft lignin. [ABSTRACT FROM AUTHOR]

Hemicelluloses, the second most abundant class of biopolymers, have emerged as an immense renewable resource of biopolymers that are recognized as currently being underutilized. Carboxymethyl carbohydrates are valuable products for thickeners, viscosity control, food additive and others. Hemicellulose isolated from poplar was converted to carboxymethyl hemicellulose using sodium chloroacetate (SCA) and sodium hydroxide (NaOH). The significance of the effects of carboxymethylation conditions in an 80% ethanol/water medium on the degree of substitution (DS) and reaction efficiency (RE) was evaluated using a definitive screening design model. There was strong evidence that the dosage of SCA and NaOH, and temperature have a significant effect on DS. A significant interaction between SCA and NaOH was also statistically confirmed. The RE resulting from the ethanol/water medium was lower than 50%. A higher RE of 72% with a DS 1.08 was achieved in a 90% tert-butyl alcohol/water medium, which was conducted at 85 °C with 120 min, 1.5 mol/mol anhydroxylose unit (AXU) of NaOH and 1.5 mol/mol AXU of SCA. The potential of using hemicellulose and carboxymethyl hemicellulose as materials to produce water-soluble films was evaluated. Due to the increased water solubility, the processing of carboxymethyl hemicellulose in water and the production of films were more facile than with unmodified hemicellulose. All of the films demonstrated significant oxygen barrier characteristics, with low oxygen permeability ranging from 0.28 to 0.55 cm3 µm/(m2 d kPa). The films did not display effective water vapor barrier characteristics, with high water vapor permeability ranging from 4.8 to 6.5 g mm/(m2 d kPa). Carboxymethylation of HC decreased the tensile strength, increased the elongation at break, and decreased the water vapor and oxygen barrier properties of the produced films. Both hemicellulose and carboxymethyl hemicellulose films could offer a bio-based and biodegradable alternative to existing synthetic oxygen barrier materials. The hemicellulose and carboxymethyl hemicellulose materials might be exploited in water-soluble films, washable fruit coating or used in composites or multilayer films in conjunction with hydrophobic layers. [ABSTRACT FROM AUTHOR]

Mechanical refining results in fiber deconstruction and modifications that enhance enzyme accessibility to carbohydrates. Further understanding of the morphological changes occurring to biomass during mechanical refining and the impacts of these changes on enzymatic digestibility is necessary to maximize yields and reduce energy consumption. Although the degree of fiber length reduction relative to fibrillation/delamination can be impacted by manipulating refining variables, mechanical refining of any type (PFI, disk, and valley beater) typically results in both phenomena. Separating the two is not straightforward. In this study, fiber fractionation based on particle size performed after mechanical refining of high‐lignin pulp was utilized to successfully elucidate the relative impact of fibrillation/delamination and fiber cutting phenomena during mechanical refining. Compositional analysis showed that fines contain significantly more lignin than larger size fractions. Enzymatic hydrolysis results indicated that within fractions of uniform fiber length, fibrillation/delamination due to mechanical refining increased enzymatic conversion by 20–30 percentage points. Changes in fiber length had little effect on digestibility for fibers longer than ~0.5 mm. However, the digestibility of the fines fractions was high for all levels of refining even with the high‐lignin content. [ABSTRACT FROM AUTHOR]

Based on publications related to the use of micro- and nanofibrillated cellulose (MNFC) in papermaking applications, three sets of parameters (intrinsic and extrinsic variables, furnish composition, and degree of dispersion) were proposed. This holistic approach intends to facilitate understanding and manipulation of the main factors describing the colloidal behavior in systems comprising of MNFC, pulp fibers, and additives, which directly impact paper product performance. A preliminary techno-economic assessment showed that cost reductions driven by the addition of MNFC in paper furnishes could be as high as USD 149 per ton of fiber (up to 20% fiber reduction without adverse effects on paper's strength) depending on the cost of papermaking fibers. It was also determined that better performance in terms of strength development associated with a higher degree of MNFC fibrillation offset its high manufacturing cost. However, there is a limit from which additional fibrillation does not seem to contribute to further strength gains that can justify the increasing production cost. Further research is needed regarding raw materials, degree of fibrillation, and combination with polyelectrolytes to further explore the potential of MNFC for the reduction of weight of paper products. [ABSTRACT FROM AUTHOR]

Hemicellulose is a polymer found abundantly in lignocellulosic feedstocks, with many potential market applications. However, there has yet to be a large‐scale commercial process to isolate hemicellulose from lignocellulosic biomass. A techno‐economic assessment for hemicellulose extraction from sugarcane bagasse, switchgrass, and poplar was made. Two isolation processes after alkaline extraction were considered: (1) producing total hemicellulose and (2) producing hemicellulose A (water‐insoluble fraction) only. In a greenfield scenario, a byproduct of the process is sugar, whereas in a co‐location scenario the biomass after hemicellulose extraction is returned to the pulp mill for its fiber value. Operating costs, capital investment, minimum hemicellulose selling price (MHSP), the effect of input material and product prices along with several other process parameters on the MHSP were determined for each scenario. Co‐location scenarios had a dramatically lower capital cost and MHSP relative to greenfield scenarios. This was due to co‐location scenarios utilizing existing biomass processing and utilities equipment and not requiring a sugar‐production process. Among the three biomasses, hemicellulose extraction from sugarcane bagasse had the lowest MHSP for all scenarios, mainly due to a higher hemicellulose extraction yield. Extraction of hemicellulose A from sugarcane bagasse in a co‐location scenario had a low capital cost of 56 million USD and had a reasonable MHSP of 274 USD/t (metric ton). This research indicates that there is reasonable economic potential for hemicellulose extraction from lignocellulosic biomass for applications to replace starch or as a starting material for the production of xylo‐oligomeric prebiotics. © 2019 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Cellulose transparent and flexible film was prepared by dissolving micro-crystalline cellulose powder in Dimethylacetamide/Lithium Chloride (DMAc/LiCl) followed by regeneration in acetone and subsequent washing with water. The solution was cast on a glass plate. The interactions of water molecules and the swollen cellulose in the gel were examined by differential scanning calorimetry, DSC. An increased melting point of water in the gel indicated the presence of stronger bonding between water and cellulose than in the non-modified cellulose. The prepared dried films had 63 g/m² weight and 0.06 mm thickness with 1.14 g/cm3 density. The prepared dry film exhibited high transparency, around 95% with visible light. The transparency and mechanical properties of the films were stable at high temperature (120°C) and exposure to UV irradiation. Thermal analysis of the prepared sample indicated film stability up to 275 °C. The tensile strength of the cellulose film was around 120 MPa with about 10% strain to break. The mechanical properties of the films were stable in alkali and acidic solutions. [ABSTRACT FROM AUTHOR]

The relationship between the types of pulp, the tissue making technologies, and shelf price of bath tissue was evaluated for the North American market. Twenty-four market tissue samples (representing approximately 80% of the current market offering) were sourced and analyzed along with their nationwide price information. Pulp composition, drying technologies, market share, sustainability advertising, and tissue properties were evaluated. Tissue properties, including softness, ball burst strength, water absorbency, density, tensile strength, and tensile modulus were measured. Among all the drying technologies, creped through-air dry (CTAD) and creped through-air dry belt (CTADB) seemed to improve tissue softness most. The UCTAD maximized tissue bulk by drying the tissue web solely using a through-air (TAD) cylinder. Tissue samples with freeness between 575 to 650 mL seemed to have their properties improved more significantly through advanced drying technologies. It was found that the retail prices of these bath tissues were directly related to softness, bulkiness, water absorbency, and basis weight. A mathematical model was conducted to predict the retail price of bath tissue (based on product performance and attributes). This paper also identified the effect of “sustainability” on the retail price. [ABSTRACT FROM AUTHOR]

New alternatives to plastic straws are being considered due to consumer demands for sustainability and recent changes in government policies and regulations, such as bans on single-use plastic products. There are concerns regarding paper straw quality and stability over time when in contact with beverages. This study evaluated the performance and properties of commercially available paper straws and their counterpart plastic straws in various intended applications. The physical, mechanical, and compositional characteristics, as well as the liquid interaction properties of the straws, were determined. The paper straws were composed mainly of hardwood fibers that were hard sized with a hydrophobic sizing agent to achieve a contact angle of 102° to 125°. The results indicated that all the evaluated paper straws lost 70% to 90% of their compressive strength after being in contact with the liquid for less than 30 min. Furthermore, the paper straws absorbed liquid at approximately 30% of the straw weight after liquid exposure for 30 min. Increased liquid temperatures caused lower compressive strengths and higher liquid uptake in the paper straws. This report provides directions and methods for testing paper straws and defines current property limitations of paper straws relative to plastic straws. [ABSTRACT FROM AUTHOR]

A comparison among ten market pulps at a laboratory scale using uncreped tissue handsheets was performed to study the performance of wood and non-wood pulps for tissue manufacturing, evaluate what fiber features are desired for a specific tissue property, and determine how non-wood pulps can be used to replace or complement wood pulps in tissue products. A characterization of the fiber morphology and handsheet properties (softness, water absorbency, and strength) was performed at different mechanical refining levels. The results showed that the fiber morphology had a major impact on tissue properties. Market pulps with a combination of long fibers, high coarseness, and low fines content can provide superior bulk and water absorbency. Short fibers with thin cell walls and low fines content can impart superior softness. Bleached bamboo soda pulp can replace hardwood and softwood pulps to provide an excellent combination of water absorbency and strength. Bleached bamboo soda pulp can also replace Northern bleached softwood kraft (NBSK) pulp to impart strength without sacrificing softness. Bleached and semi-bleached wheat straw soda pulps presented a similar combination of softness and strength as Southern bleached hardwood kraft (SBHK) pulp. The wheat straw pulps can be used to replace deinked pulp (DIP) pulp to impart intermediate levels of water absorbency and strength. [ABSTRACT FROM AUTHOR]

A rapid and green preparation of lignin nanoparticles was demonstrated starting from bio-refinery lignin containing grafted carbohydrates. The particles were prepared by recovering a fraction of the lignin, which contained 24% carbohydrate (by weight) as the insoluble fraction in 0.5 M NaOH. The carbohydrate content of this fraction was verified with a wet chemistry analytical technique, nuclear magnetic resonance, and X-ray diffraction. This fraction was then dissolved in a NaOH/urea/water system and added dropwise to water under a high shear, which rapidly formed precipitated particles in a size range of approximately 100 nm. This carbohydrate-containing fraction of the lignin was soluble in a green solvent system that was not suited for lignin alone. The generated particles were stable in different organic solvents and water. Overall, the dissolution of the bio-refinery lignin in the NaOH/urea/water system, followed by precipitation in water can be regarded as a green and rapid method to produce stable nanoparticles. The generated nanoparticles, containing both carbohydrates and lignin, are expected to have unique applications because of their bi-component nature. Furthermore, this is the first publication to show how materials with high levels of lignin can be solubilized in solvents that are conventionally used for cellulose. [ABSTRACT FROM AUTHOR]

A new Pd catalyst chemically bonded to cellulose nanocrystals surfaces (CNC-BIA-Pd) was developed. 2-(1H-Benzo[d]imidazol-2-yl) aniline (BIA), tosylated cellulose nanocrystals (CNC-TOS) and PdCl2 were the reactants for the synthesis of the new catalyst designed to be used for the Ullmann reaction. The modified cellulose nano catalyst was characterized with various analytical tools. The catalyst had excellent selectivity and activity in a short reaction time (45 min) and outstanding TON (490) and TOF (1960) values. The nano catalyst was determined to be reusable for at least eight cycles. The CNC-BIA-Pd catalyst indicated excellent catalytic efficiency for the Ullmann C–O reaction when it was compared to commercial palladium catalysts. A new Pd catalyst chemically bonded to cellulose nanocrystal surfaces (CNC-BIA-Pd) was developed and used for the Ullmann reactions. The catalyst had excellent selectivity and activity in a short reaction time and outstanding TON (490) and TOF (1960) values. The nano catalyst was determined to be reusable for at least eight cycles. [ABSTRACT FROM AUTHOR]

The extractability of hemicellulose from different lignocellulosics depends on the source of biomass. Differences in hemicellulose extractability are believed to be due to plant-specific hemicellulose arrangement alongside lignin within the cell wall. In this research, six biomasses were used to probe hemicellulose alkaline extractability as a function of the native lignin within the biomasses. Quantitative 2D-HSQC and 13C NMR analysis were performed to determine the S/G (S: syringyl, G: guaiacyl) and lignin-carbohydrate complex (LCC) linkages of milled wood lignin isolated from these biomasses. A strong negative correlation was observed between total lignin content and hemicellulose extractability, demonstrating that a greater presence of lignin in the original material results in lower xylan solubilization. In addition, a correlation between S/G of lignin and xylan dissolution was found within a group of hardwoods and within a group of non-woods. This suggests that monomeric constituency also influences xylan's propensity for dissolution in 10% NaOH. Although there is some uncertainty in the quantification of LCC linkages, both non-woods and hardwoods exhibited negative correlations between alkaline-stable LCC linkages content and xylan extractability. This suggests that alkaline-stable LCC structures are associated with a decrease in the alkaline extractability of hemicellulose. [ABSTRACT FROM AUTHOR]

Softness, as a subjective perception, is difficult to define and quantify. For decades, panel tests have been used to judge differences in the softness of hygiene tissue samples. Panel tests can be a time-consuming and expensive process. A number of protocols have been developed to quantify the physical properties of tissues associated with softness. The Tissue Softness Analyzer (TSA) by Emtec has gained popularity in characterizing the physical properties of tissues associated with softness. The instrument was designed with softness in mind and attempts to simulate the touch of the human hand. There is currently no comprehensive study that compares the results from a TSA and human panel. In this work, panel tests were used to validate the performance of the TSA with bath tissue. It was determined that one component of the TSA measurements (TS7) linearly correlated with the panel results. Among all of the algorithms available for use with the TSA, the TP2 algorithm most accurately predicted the panel scores. The TSA performed better in predicting the softness of the samples that were dried with a conventional wet press or creped-through air-dryer. [ABSTRACT FROM AUTHOR]

Hemicellulose is an abundant and underutilized carbohydrate polymer in plants. The objective of this study was to understand the effect of delignification on hemicellulose extraction efficiency with different types of lignocellulosic biomass. In the case of pine, with a prior sodium chlorite or peracetic acid delignification, more than 50% of the original hemicellulose in the biomass could be extracted using a 10% sodium hydroxide solution; without delignification, only 3.4% of hemicellulose could be extracted from pine. In contrast, without prior delignification, acceptable hemicellulose extraction efficiencies (55.5% and 50.7%, respectively) were achieved from switchgrass and poplar. In addition, the effect of hemicellulose extraction processes on the enzymatic convertibility of the celluloserich residues after extraction was determined. The cellulose-rich residues from switchgrass after hemicellulose alkali extraction showed high glucose recovery with enzyme hydrolysis with or without prior delignification. For pine and poplar, high glucose recovery with enzyme hydrolysis of the cellulose-rich residues only occurred if the sample had a delignification step prior to hemicellulose extraction. This information on commercially available biomass feedstocks is useful for those considering isolating hemicellulose within a biorefinery concept. [ABSTRACT FROM AUTHOR]

Conversion economics, risk, and fi nancial analyses for an industrial facility manufacturing cellulose micro- and nanofibrils (CMNF) from wood pulp is presented. Process data is based on mass and energy balances from a pilot facility in the University of Maine. Here, CMNF is produced from untreated wood pulp by using disk refining, with an assumed production capacity of 50 t (dry metric ton equivalent) per day. Stand-alone and co-location manufacturing facilities were simulated and assessed. Minimum product selling prices (MPSP, estimated to achieve a 16% hurdle rate) for different scenarios ranged from USD 1893/t CMNF to USD 2440/t CMNF (dry equivalent). Pulp and energy consumption were identified as major cost drivers. Consequently, it was found that the use of alternative feedstock, in addition to co-location configuration, can reduce MPSP by 37%. Since estimated MPSP of CMNF is lower than cellulose nanocrystals (CNC) - both estimated to achieve a 16% hurdle rate, we believe market adoption of CMNF in the near term is more promising, regardless of specific applications. This study provides state of the art business intelligence information on the conversion economics, risk, and fi nancial analyses for CMNF manufacturing. Thus, the data represents valuable information to entrepreneurs, R&D scientists, and product developers who plan to adopt CMNF in their processes and products. [ABSTRACT FROM AUTHOR]

There is a significant need to not only understand how different industries contribute to overall wealth but how they affect certain segments of society. This study augments input-output social account matrix (SAM) modeling techniques with American Community Survey (ACS) Public Use Microdata Samples (PUMS) to better characterize North Carolina forest products industry earnings' impact on low-, medium-, and high-income households. A 2014 North Carolina SAM was created using IMpact Analysis for PLANning (IMPLAN) and customized so that industry-specific earnings were allocated to household income classes according to the distributions contained within the ACS-PUMS data set. Multipliers were determined to describe earnings distributions per dollar change of final demand. These multipliers were then contextualized by perturbing the SAM model with a 10% change in final demand for relevant forest product industries. The results of the analysis indicate that SAM analysis methods based on unmodified IMPLAN models underestimate earnings paid to low-income and overestimate earnings paid to high-income households resulting from economic growth in the study area. Scenario results obtained using our updated SAM model highlight the improved analytical capabilities of this approach for measuring impacts across income class. [ABSTRACT FROM AUTHOR]

Mechanical refining has potential application for overcoming lignocellulosic biomass recalcitrance to enzyme hydrolysis and improving biomass digestibility. This study highlighted the ability for a pilot scale disc refiner to improve the total carbohydrate conversion to sugars from 39% (unrefined hardwood sodium carbonate biomass) to 90% (0.13 mm gap, 20% consistency, ambient temperature) by optimizing the refining variables. The different biomass properties that changed with refining indicated the expected increase in sugar conversion. Controlling the refining parameters to narrower gaps and higher consistencies increased the resulting refined biomass hydrolysis. Positive correlations that increases in net specific energy (NSE) input and refining intensity (SEL) improved the enzymatic hydrolysis. In some severe cases, over-refining occurred when smaller gaps, higher consistencies, and more energy input reached a point of diminished return. The energy input in these scenarios, however, was much greater than realistically feasible for industrial application. Although well-established in the pulp and paper industry, gaps in understanding the fundamentals of refining remain. The observations and results herein provide the justification and opportunity for further mechanical refining optimization to maximize and adapt the mechanical refining technology for maximum efficiency within the process of biochemical conversion to sugar. [ABSTRACT FROM AUTHOR]

Cellulose extracted from recycled pulverized cotton in nanocrystalline cellulose (CNC) and nanofibrillated cellulose (NFC) forms is investigated as a reinforcing agent in low-density polyethylene (LDPE) nanocomposites. The effect of extraction processing on the pulverized cotton is shown to influence the degree of crystallinity, morphology, and thermal stability of cellulose nanomaterials. Melt compounding of CNC with LDPE resulted in polymer nanocomposites with no discoloration at 170 °C. Significant differences observed in transparency, mechanical, and thermal properties of LDPE nanocomposite films, are demonstrated to be a result of the microstructure and the content of cellulose nanomaterials. Thermal analysis using thermogravimetric analyzer and differential scanning calorimeter showed higher thermal stability and degree of crystallinity of NFC/LDPE comparing to CNC/LDPE nanocomposite films. Tensile analysis exhibited a higher elastic modulus and tensile strength for the NFC material. 10 wt% of NFC reinforcing agent showed 32% improved strength and higher transparency over the one with CNC. [ABSTRACT FROM AUTHOR]

Purpose: Greenhouse gas (GHG) emissions resulting from biofuel production and use often occur over many different years. Nondynamic GHG accounting methods traditionally sum the global warming impacts (GWIs) occurring over a 100-year period for all emissions occurring in the life cycle regardless of emission timing. When examining biofuels from a policy perspective, time horizons are chosen to determine the benefits a policy or action has over a desired time period. It is critical to only account for impacts occurring within the given time period by having consistent temporal boundaries. When calculating the GWI as a function of time, additional assumptions and data are required. These assumptions have implications on the results and are explored herein to determine their influence on the overall conclusions when comparing biofuels made from different cellulosic feedstocks. Materials and methods: The time zero assumption of both biomass planting and harvesting was examined. Analytical time horizon choice was also tested by examining results on a 25-, 50-, 100-, and 500-year time horizon. GWIs using dynamic GHG accounting methods were compared to nondynamic GWI method results. Direct land use change (LUC) emissions were determined for the different feedstock conversion scenarios and used to calculate a payback period for switchgrass and sweet sorghum biofuel scenarios. Dynamic biofuel life cycle emissions were also modeled for biofuel scenarios where LUC emissions were negative in the case of converting cropland to forests. Results and discussion: Biofuel life cycle emissions and GHG reductions compared to gasoline were highly sensitive to GHG accounting methods and time horizons. The time zero assumption had greater influence on the results when shorter time horizons were chosen and decreased as time horizons approached 500 years. Using the dynamic GHG accounting method, LUC payback periods were determined to be greater compared to a 0 % emission discount method. Payback periods using a discount rate of 2 and 3 % were at times greater and less than dynamic GHG accounting method results. Conclusions: The data presented herein suggest that time zero and other temporal emission timing assumptions are important and influence the overall study results. Analytical time horizons were also shown to be important and significantly influence the overall results, as well as be important to achieving carbon mitigation goals. Dynamic GHG accounting was shown to be a more robust method than the traditional static GWI accounting method ensuring consistent temporal boundaries; however, dynamic inventories require additional emission timing details and assumptions that require more effort and resources to model. [ABSTRACT FROM AUTHOR]

Life cycle assessments (LCAs) have become a common tool for measuring the environmental performance of various products and processes. This study reviewed the life cycle of lignocellulosic biomass feedstock-based (pine, eucalyptus, and switchgrass) ethanol biofuels and compared the results to gasoline. Uncertainty analysis of the cradle-to-wheel results was conducted using a pedigree matrix method to address uncertainty of life cycle inventory items. A tool called stochastic multi-attribute analysis for life cycle impact assessment (SMAA-LCIA) was used to interpret the results generated from the LCA. The normalized results showed that gasoline had high environmental impacts in categories such as carcinogenics and global warming, followed by switchgrass. But the use of a single-score metric indicated that all bio-based feedstocks had similar environmental performance, all significantly better than gasoline. The SMAA-LCIA results showed that when all impacts were weighted equally, the preference from highest to lowest was for loblolly pine, eucalyptus, gasoline, and switchgrass. This rank order switched when differing weighting schemes of Producer, User, and LCA Expert were used. Overall, this method highlights the trade-offs associated with the selection of different feedstocks and improves the comparison of overall results amongst fuel sources, which can then be more clearly presented to a decision-maker. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]

Hemicelluloses, due to their hydrophilic nature, may tend to be overlooked as a component in water-resistant product applications. However, their domains of use can be greatly expanded by chemical derivatization. Research in which hydrophobic derivatives of hemicelluloses or combinations of hemicelluloses with hydrophobic materials are used with to prepare films and composites is considered herein. Isolation methods that have been used to separate hemicellulose from biomass are also reviewed. Finally, the most useful pathways to change the hydrophilic character of hemicelluloses to hydrophobic are reviewed. In this way, the water resistance can be increased and applications of targeted water-resistant hemicellulose developed. Several applications of these materials are discussed. [ABSTRACT FROM AUTHOR]

Early-stage evaluation of biofuel and bioproduct technologies is extremely complicated and involves many disparate feasibility criteria, including technical, financial, environmental, logistic, legal, social, and other aspects. Problems can arise for decision-makers when evaluating renewable technologies at this early stage due to bias, shifting preferences or priorities, occurrence of trade-offs, and decision-making complexity. Thus, a method is needed for evaluating disparate, typically non-comparable criteria concurrently. In Part 1 of this research, cradle-tograve environmental LCA was conducted for biomass delivery to a biosugar refinery using Ecoinvent v2.2 data and the TRACI 2 impact assessment method for midpoint impacts. Biomass availability, delivered cost, sugar yield, transportation distance, harvestable months per year, and other aspects of supply chain feasibility were measured for eighteen feedstock biomass types. In Part 2, stochastic multi-attribute analysis (SMAA) was used alongside LCA to develop an environmental preference single-score probability distribution function for feedstock alternatives. Weighted single-scoring and ranking, using multi-criteria decision-making analysis (MCDA), was conducted considering five criteria of biomass supply feasibility: biomass delivered cost, biosugar yield, harvestable months, transport distance, and environmental preference single-score. Corn was shown to cost the most, followed by switchgrass and U.S. primary forest products. Transport distance was found to be highest for residues due to low yield per acre and low covered area. Results of MCDA show that Brazilian eucalyptus and Malaysian empty fruit bunch biomass types were consistently preferred relative to other biomass types. In the U.S., Genera biomass sorghum is most holistically preferred. It is shown that SMAA is helpful for translating LCA data for decision science. It was shown that MCDA can be useful for early-stage biorefinery technology commercialization decision-making, using the novel decision science tool described herein. [ABSTRACT FROM AUTHOR]

Lignin-based thermoplastic materials have attracted increasing interest as sustainable, cost-effective, and biodegradable alternatives for petroleum-based thermoplastics. As an amorphous thermoplastic material, lignin has a relatively high glass-transition temperature and also undergoes radical-induced self-condensation at high temperatures, which limits its thermal processability. Additionally, lignin-based materials are usually brittle and exhibit poor mechanical properties. To improve the thermoplasticity and mechanical properties of technical lignin, polymers or plasticizers are usually integrated with lignin by blending or chemical modification. This Review attempts to cover the reported approaches towards the development of lignin-based thermoplastic materials on the basis of published information. Approaches reviewed include plasticization, blending with miscible polymers, and chemical modifications by esterification, etherification, polymer grafting, and copolymerization. Those lignin-based thermoplastic materials are expected to show applications as engineering plastics, polymeric foams, thermoplastic elastomers, and carbon-fiber precursors. [ABSTRACT FROM AUTHOR]

Chemical production from crude oil represents a substantial percentage of the yearly fossil fuel use worldwide, and this could be partially offset by renewable feedstocks such as woody biomass and energy crops. Past techno-economic and environmental analyses have been conducted for isolated feedstocks on a regional or national scope. This study encompasses complete supply chain logistics analysis, delivered cost financial analysis, national availability, and environmental life cycle assessment (LCA) for 18 selected cellulosic feedstocks from around the world. A biochemical conversion route to monomeric sugars is assumed for estimated sugar yields and biosugar feedstock cost analysis. US corn grain was determined to have the highest delivered cost, while rice hulls in Indonesia resulted in the lowest cost of the feedstocks studied. Monomeric sugar yields from literature ranged from 358 kg BDMT-1 for US forest residues to 700 kg BDMT-1 for corn syrup. Environmental LCA was conducted in SimaPro using ecoinvent v2.2 data and the TRACI 2 impact assessment method for mid-point impacts cradle-to-incoming biorefinery gate. Carbon absorption during biomass growth contributed most substantially to the reduction of net global warming potential. Rice hulls and switchgrass resulted in the highest global warming potential, followed closely by corn and Thai sugarcane bagasse. Contribution analysis shows that chemical inputs such as fertilizer use contribute substantially to the net environmental impacts for these feedstocks. [ABSTRACT FROM AUTHOR]

Mandated Environmental Protection Agency biofuel qualifications focused on greenhouse gas ( GHG) emissions and fossil fuel use are limited in perspective and have the potential to encourage burden shifting. When a broader host of environmental impacts are examined, environmental trade-offs often exist when biofuels are compared to gasoline. Multivariate analysis methods examining a wide variety of weighting value systems and methodology assumptions were used to determine process design options with the lowest overall environmental impact. A multivariate environmental analysis was applied to the dilute acid pre-treatment process followed by enzymatic hydrolysis and the fermentation process for converting loblolly pine, eucalyptus, natural hardwood, switchgrass, and sweet sorghum biomass to ethanol. The influence of co-product treatment method choices, inclusion of direct land-use change, and electrical grid assumptions were examined using 16 different weighting methods to create a single score result. Biofuel system rankings based on GHG emissions following the Renewable Fuel Standards 2 ( RFS2) methods were very sensitive to the co-product treatment method, inclusion of land-use change emissions, and energy grid assumptions. The multivariate analysis ranking was heavily influenced by other environmental impacts resulting from the production of process chemicals used in ethanol conversion. Weighting methods examined had no influence on the environmental preference ranking of the biofuel scenarios. Additionally, the biofuel ranking based on the RFS2 methodology was different than the ranking following the multivariate approach examining additional impacts. These findings demonstrate a robust approach to biofuel life cycle assessment ( LCA) scenario analysis and suggest that the limited scope of the RFS2 environmental analysis could result in burden shifting. © 2015 Society of Chemical Industry and John Wiley & Sons, Ltd [ABSTRACT FROM AUTHOR]