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Silage processing has a crucial positive impact on the methane yield of anaerobic treated substrates. Changes in the characteristics of switchgrass after ensiling with different additives and their effects on methane production and microbial community changes during anaerobic digestion were investigated. After ensiling (CK), methane yield was increased by 33.59% relative to that of fresh switchgrass (FS). In comparison with the CK treatment, methane production was improved by 17.41%, 13.08% and 8.72% in response to ensiling with LBr + X, LBr and X, respectively. A modified Gompertz model predicted that the optimum treatment was LBr + X, with a potential cumulative methane yield of 178.31 mL/g total solids (TS) and a maximum biogas production rate of 44.39 mL/g TS·d. Firmicutes and Bacteroidetes were the predominant bacteria in FS and silage switchgrass; however, the switchgrass treated with LBr + X was rich in Synergistetes , which was crucial for methane production. [ABSTRACT FROM AUTHOR]

The cassava stem is found to be one of few crop residues containing starch (up to 42% of dry mass) that may be converted to fuel ethanol. The current study was to evaluate the influence of parameters genotype, growth location and harvest time on cassava stem starch contents and yields as well as consequences in ethanol production (non-cellulosic process), based on 180 samples from a full factorial design experiment (3 varieties × 3 locations × 5 harvest times) in Guangxi, China. The potential utilization of stem starch and soluble sugar that varied 14–42% and 3–12.1% of dry mass, respectively, can correspond to an increase of 26% in ethanol production compared to that produced by roots only. The cassava stem starch content was significantly affected by all three studied parameters and location had the largest effect followed by variety and harvest time, while the stem starch yield was significantly affected by location only. The starch and soluble sugar content were significantly correlated with soil properties, e.g., soil pH and organic carbon, S and P contents. A general and positive correlation was also found between the stem and root starch, suggesting a promising potential of using stem starch without reducing root starch production. [ABSTRACT FROM AUTHOR]

Given the growing global population, mankind must find new ways to lower competition for land between food and fuel production. Our findings for cassava suggest that this important crop can substantially increase the combined production of both food and fuel. Cassava stems have previously been overlooked in starch and energy production. These food-crop residues contain about 30% starch (dry mass) mostly in the xylem rather than phloem tissue. Up to 15% starch of the stem dry mass can be extracted using simple water-based techniques, potentially leading to an 87% increase in global cassava starch production. The integration of biofuel production, using residues and wastewater from starch extraction, may bring added value. The cassava roots on which biofuels and other products are based can be replaced by cassava stems without land use expansion, making root starch available as food for additional 30 million people today. [ABSTRACT FROM AUTHOR]

Abstract: The effect of temperature on the functionality of microbial community structure in a low temperature, anaerobic fixed-bed reactor was studied by decreasing the operating temperature from 18°C to 5°C. The reactor was productive within 20days and produced stable methane content in biogas (above 77%) throughout the trial period. At 17°C and 15°C, chemical oxygen demand (COD) removal efficiency and biogas production of reactor were significantly reduced. These might be temperature thresholds when fixed-bed reactors are operated under low temperatures. The methanogen community composition was analyzed using 16S rRNA gene clone library screening and quantitative PCR. At low ambient temperatures, Methanomicrobiales were dominant methanogens, and they preferentially adhered to the carbon fiber carrier. The results indicated that 16S rRNA levels of Methanomicrobiales and Methanosaetaceae in adhering sludge were higher than in deposited sludge, and they all contributed to the efficient performance of the fixed-bed reactor at low operating temperatures. [Copyright &y& Elsevier]

[Display omitted] • Fluid shear as a novel force was effective in driving biomass pretreatment reactions. • 90% of lignin and hemicellulose in biomass could be separated by fluid shearing. • Glucose yield via enzymatic hydrolysis tripled after fluid-shear pretreatment. • The obtained lignin kept a structure similar to that of native lignin. • Mechanism of biomass pretreatment by fluid shearing was preliminarily revealed. Pretreatment is the initial stage of lignocellulosic biorefinery process, but is limited by the time-consuming processes, harsh conditions and/or undesirable products. Herein, a mild (<60 °C) and highly efficient pretreatment strategy is developed. The novel mechanocatalytical reaction system driven by fluid shear force helps to exfoliate cellulose from lignocellulose, and the heat generated by the shear process can be used to precipitate and recover the dissolved cellulose from the precooled NaOH/urea solution. The regenerated cellulose shows satisfying crystal structure (cellulose II), significantly decreased crystallinity and nearly tripled enzymolysis glucose yield. Almost 90% of lignin and hemicellulose could be rapidly separated. The separated lignin shows a nearly native structure with 64% β-O-4 linkage, which is even higher than the ball-milling lignin (60%). This research provides a theoretical guidance for the mild pretreatment of lignocellulosic biomass, which will push the application of mechanocatalytical reaction system in biorefinery processes on a large scale. [ABSTRACT FROM AUTHOR]

The utilization of biomass for the production of agricultural green inputs is regarded as a crucial strategy for achieving low-carbon development in agriculture, while also fully harnessing the potential of renewable resources. Pesticides, as a vital agricultural input, often encounter issues pertaining to inefficient usage, resulting in significant environmental pollution and economic losses. As a main component of lignocellulosic biomass, lignin has become one of the most appealing biopolymers for the construction of advanced pesticide delivery systems. This review aims to provide a thorough summary of the advancements in lignin-based controlled release formulations (LCRFs) for the precise delivery of pesticides. The research in this field has experienced rapid growth in the past five years, making it an important area of study. Common LCRFs are introduced, and the factors influencing the release of active ingredients (AIs) within different LCRFs are analyzed. Special emphasis is placed on intelligent-responsive LCRFs, encompassing an overview of the existing formulations and an exploration of their potential application scenarios and development strategies. It is crucial to promote innovation in pesticide formulations based on the actual demands of agricultural production. We hope this review will stimulate the high-value utilization of lignin and the green development of plant protection technologies. [ABSTRACT FROM AUTHOR]

In pursuit of low-carbon development, the production of diverse functional materials from renewable resources, especially lignocellulosic biomass, is of vital importance. Lignin is a major component of lignocellulose, and it is nature's only true high-volume aromatic polymer, which has the advantages of biodegradability, biocompatibility, and low acquisition cost. After modification by a variety of physicochemical strategies, it can be applied as an alternative to basic industrial materials, including polyurethanes, phenolic, and epoxy resins, which stands comparably to conventional synthetic polymers in terms of both performance and reduced cost. To further unlock the potential of lignin, an alluring opportunity is the exploitation of lignin for high-value materials, especially nanomaterials, that find extensive applications in energy and environment areas. This review provides a systematic summary and perspective of research that has been devoted to lignin transformation to high-value materials, ranging from industrially well-established engineering materials to the recently emerged nanomaterials that were used for energy and environment applications. Latest cutting-edge innovations on lignin modification, controlled depolymerization, and assembly during the last five years are summarized. Structure-function relationships of lignin materials in terms of their specific applications are analyzed. Furthermore, challenges and future opportunities for lignin conversion to high-value materials are also provided. We wish this review will stimulate further advances in lignin based high-value materials, and promote "waste" into "wealth". • Lignin-based materials are the way of high-value utilization of biomass. • The development of lignin chemistry is reviewed in this paper. • The modification methods of lignin are summarized. • The application of lignin-based polymer materials is evaluated. • Lignin-based nanomaterials and lithium battery materials are summarized. [ABSTRACT FROM AUTHOR]

The extremely low utilization efficiency of pesticides has driven people to develop low‐cost, sustainable, and smart delivery systems. Pickering emulsion (PE) derived from biomass is an attractive candidate. However, the stability of PE is insufficient, and pesticide release from PE can be hardly tuned. Herein, a facile in situ PE modification strategy to construct a stable and high‐performance pesticide delivery system from biomass resources is reported. In this process, PE stabilized by alkali lignin nanoparticles is initially prepared, and subsequently, opposite‐charged chitosan (CH), and sodium lignosulfonate (SL) are alternatively deposited onto the PE interface through layer‐by‐layer assembly to form a microcapsule system (CH+SL)n@PE. The resulting biomass‐based microcapsules show improved stability, high encapsulation efficiency, and super UV protection to avermectin (AVM), a hydrophobic and photo‐sensitive pesticide. Furthermore, the shell thickness of microcapsules can be finely tuned by controlling the deposited CH+SL layers, which enable (CH+SL)n@PE to have adjustable release behaviors. (CH+SL)20@PE prolongs the half‐life of AVM under UV irradiation by 5.0‐fold. Moreover, (CH+SL)n@PE exhibits pH and laccase dual responsiveness, which is beneficial to the targeted release of AVM in vivo. Therefore, the current PE modification strategy can provide an eco‐friendly, low‐cost, and smart system for precise delivery of pesticides. [ABSTRACT FROM AUTHOR]

Abstract: The development of inexpensive and effective catalysts that can produce hydrogen from methanol is attractive for the implementation of clean energy technologies. Cu-Al oxides, prepared by different methods, were tested for hydrogen production from methanol decomposition. Catalysts with spinel CuAl 2 O 4 (copper aluminate) structure as compared with non-spinel Cu-Al oxides, are more stable, and exhibit higher catalytic activity despite of their low surface area. Spinel CuAl 2 O 4 synthesized by citrate process show better performance towards methanol decomposition than that obtained by co-precipitation process. The selectivity to H 2 +CO can be improved by the impregnation of potassium in spinel CuAl 2 O 4 . However, the direct addition of potassium during the citrate process strongly inhibited the formation of CuAl 2 O 4 structure, thus leading to a low catalytic activity. CuAl 2 O 4 was found to be a reservoir of Cu, slowly releasing Cu during the catalysis of methanol decomposition and preventing Cu from quick sintering. [ABSTRACT FROM AUTHOR]

[Display omitted] • DOC was the foremost parameter influencing the phytotoxicity of LD. • Temperature accelerated the stability and phytotoxicity disappearance of LD. • Open storage of LD at 30 °C for 60 days and 20 °C for 90 days of LD was safe. • Hermetic storage of LD at 30 °C for 120 days and 20 °C for 150 days of LD was safe. • For storage at 10 °C for 180 days, additional post-treatment is required. Identifying the stability and phytotoxicity of liquid digestate (LD) is necessary for safe agricultural utilization. Storage temperature, method, and time are critical factors that affect the stability and phytotoxicity of LD. This study therefore aimed to explore the dynamics of stability, phytotoxicity, and microbial community of LD in cattle farms under different storage conditions. The results showed that the contents of solids, organic matter, nitrogen, and phosphorous decreased during storage and exhibited temperature dependency. Conversely, the seed germination index increased, which was negatively correlated with dissolved organic carbon and ammonium nitrogen and positively correlated with certain bacteria (Thermovirga and Fastidiosipila). Open storage and/or higher temperature were found to contribute to the stabilization efficiency and phytotoxicity disappearance of LD. Open storage of LD at 30 °C for 60 days and 20 °C for 90 days was safe for its agricultural utilization, while hermetic storage of LD at 30 °C for 120 days and 20 °C for 150 days was safe. However, for storage at 10 °C for 180 days, additional post-treatment is required. [ABSTRACT FROM AUTHOR]

Cassava ( Manihot esculenta Crantz) stems, being waste residues after harvesting starchy roots, are a potential biofuel resource. However high concentrations of ash and elements Cl, K, etc. in the stems may cause severe deposition, corrosion and particle emissions, in addition to slagging during combustion. This study tests washing by water as a pretreatment to reduce the problems. A 3-level full factorial designed experiment was conducted with washing time (< 1800 s) and temperature (20–40 °C) as factors and fuel characteristics as responses. The effect of milling particle size was also examined in a supplementary experiment. After washing, the net calorific value of the biomass tended to be higher, though not significant. Both washing time and temperature increased C but decreased H, while N and S content decreased with time only. A short washing of 50 s decreased the ash content by approximately 50% and Cl around 75%, followed by K and P that decreased to 50% after 5 min. Smaller milling size resulted in a larger amount of starch washed away, but no significant change in content of total ash and individual elements, except for Cl which was significantly higher in the smaller particles. The effect of washing on the ash composition is visualized in a ternary diagram, showing that the risk for slagging and fine particle emissions is reduced. A reduction in the risk of corrosion is also predicted as indicated by a relatively higher ratio of S/Cl and lower Cl/(K + Na). Thus, in addition to extraction of starch, the washing can also improve fuel quality of the residual biomass. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ensiling EWS with acetic acid or heterofermentative LAB addition was first studied. • Ensiling EWS with additives enhanced acetic acid fermentation. • Ensiling EWS with additives preserved hemicellulose and cellulose content. • Ensiling EWS with additives changed the homo-fermentation to hetero-fermentation. • Ensiling EWS with additives improved the methane yield by 17.7–23.9%. Ensiling is an effective storage strategy for agricultural biomass, especially for energy crops (mainly energy grasses and maize). However, the ensiling of excessively wilted crop straw is limited due to material characteristics, such as a high lignocellulosic content and low water-soluble carbohydrate and moisture contents. In this study, acetic acid or hetero-fermentative lactic acid bacterial community (hetero-fermentative LAB) were employed as silage additives to improve the ensiling process of excessively wilted wheat straw (EWS). The results showed that the additives inhibited the growth of Enterobacteriaceae and Clostridium_sensu_stricto_12 , whose abundances decreased from 55.8% to 0.03–0.2%, respectively. The growth of Lactobacillus was accelerated, and the abundances increased from 1.3% to 80.1–98.4% during the ensiling process. Lactic acid fermentation was the dominant metabolic pathway in the no additive treatment. The additives increased acetic acid fermentation and preserved the hemicellulose and cellulose contents, increasing the methane yield by 17.7–23.9%. This study shows that ensiling with acetic acid or hetero-fermentative LAB is an effective preservation and storage strategy for efficient methane production from EWS. [ABSTRACT FROM AUTHOR]

Developing cost-effective and highly active catalysts for the selective hydrogenation of furfural to target products is significant yet remains a substantial conundrum in the chemical industry. Herein, we present a phytic acid-assisting pyrolysis strategy to phase-controlled synthesis of a series of nickel phosphides catalysts (Ni 3 P/mSiO 2 , Ni 12 P 5 /mSiO 2 and Ni 2 P/mSiO 2), which exhibited phase-dependent catalytic performance in furfural hydrogenation. Ni 12 P 5 /mSiO 2 achieved the highest yield (97.3 %) of cyclopentanone under 1 MPa H 2 at 150 °C, and Ni 3 P/mSiO 2 could further hydrogenate cyclopentanone to a 60.8 % yield of cyclopentanol when the H 2 pressure increased to 2 MPa. Meanwhile, Ni 2 P/mSiO 2 demonstrated temperature-controlled selectivity for switching between furfuryl alcohol and cyclopentanone. Detailed characterizations and density functional theory calculations elucidated that the differences in catalytic performance were primarily attributed to the hydrogenation ability and acidity of catalysts as well as furfural adsorption configuration, which were determined by the tunable crystal phases of nickel phosphides. This work paves the promising avenue for the rational design of metal phosphide catalysts and harnessing their considerable potential for biomass conversion. [Display omitted] • Phytic acid-assisting pyrolysis strategy was proposed for phase-controlled synthesize nickel phosphide catalysts. • Nickel phosphide catalysts show interesting phase-dependent catalytic performance for hydrogenation of furfural. • Phase-tuning induced increase of available catalytic active sites and optimization of surface electronic structures. • DFT calculations reveal the promotional effect of tilted adsorption configuration for hydrogenation rearrangement. [ABSTRACT FROM AUTHOR]

[Display omitted] • Illumination and photoactivated nanomaterials were employed for anaerobic digestion. • Incorporating Fe 3 O 4 into g-C 3 N 4 formed an excellent electron transfer mediator. • The highest methane enhancement (23%) was obtained under optimized conditions. • Photoelectrons improved the electron transfer efficiency of microorganisms. • Enhanced acetoclastic methanogenic pathway contributed to methane enhancement. This study proposes a novel anaerobic digestion (AD) strategy combining recyclable photoactivated nanomaterials with illumination to enhance electronic transfer for anaerobic microorganisms. Results showed that 7000 Lux illumination increased methane production yield and rate. Incorporating Fe 3 O 4 into graphite carbon nitride (g-C 3 N 4) created a recyclable Fe 3 O 4 /g-C 3 N 4 (FG) nanocomposite with improved light absorption, conductivity, redox properties, and methane promotion. The highest methane yield from corn straw was achieved with 7000 Lux and 1.5 g/L FG nanocomposite, 22.6% higher than the dark control. The AD system exhibited increased adenosine triphosphate content, improved redox performance, reduced electron transfer resistance, and higher photocurrent intensity. These improvements bolstered the microorganisms and key genes involved in hydrolysis and acidification, which in turn optimized the acetoclastic pathway. Furthermore, this strategy promoted microorganisms associated with direct interspecies electron transfer, fostering a favorable environment for methanogenic activities, paving the way for future anaerobic reactor developments. [ABSTRACT FROM AUTHOR]

Hydrodeoxygenation (HDO) reactions are extensively employed in the conversion of biomass to advanced fuels, which rely heavily on bifunctional catalysts that contain both a metal component and an acidic component. A significant challenge in the development of HDO catalysts is the need to reduce costs while simultaneously enhancing catalytic efficiency. Here, a series of Ru@W/ZrO 2 catalysts with an extremely low loading of Ru (0.5 wt%) were successfully synthesized using different Ru or W loading sequences and different Ru/W mass ratios. The catalysts were applied in the HDO reaction of lignin-derived phenols, and their physical and chemical characteristics were revealed by various characterization techniques, including XRD, H 2 -TPD, NH 3 -TPD, and XPS. The results suggest that the synthesis method with post-loading Ru leads to improved exposure and utilization of the low-loaded Ru, which effectively serves as the active sites for hydrogenation in catalytic reactions. Under the same reaction conditions, the bifunctional catalyst with post-loading of Ru achieved a complete conversion of phenol into cyclohexane, while the catalyst with simultaneous loading of Ru and W only yielded 42% of cyclohexane. In addition, the Ru/W ratios have also shown significant effects on the HDO performance of the catalyst. The catalyst exhibits the highest hydrogenation activity when the Ru/W ratio is 10, which is further supported by kinetic experiments. This study highlights the significance of the loading sequence of noble metals and the metal/acid ratio in the synthesis of highly active bifunctional catalysts, and also lays the groundwork for the efficient utilization of noble metals in biomass HDO conversion. • Bifunctional catalyst with extremely low loading of Ru was synthesized for bio-jet fuel production. • The post loading of Ru maximized the noble metal utilization, leading to superior catalytic performance. • The Ru/W ratios significantly affect the hydrodeoxygenation performance of the catalyst. • Lignin derived phenols were efficiently converted into cycloalkanes by the developed catalyst. [ABSTRACT FROM AUTHOR]

In pursuit of a more green and sustainable society, the preparation of versatile chemicals from renewable biomass is essential. Nitrogen-containing chemicals, as compared with hydrocarbon fuels or oxygen-containing compounds, usually have higher values and play key roles in modern industry. The industrial synthesis of nitrogen-containing chemicals relies heavily on the Haber–Bosch process, a high-energy-consumption and environment-polluting process. Therefore, the production of these organonitrogen chemicals from biomass has attracted increasing interest in recent years. Chitin is the most abundant nitrogen-containing biopolymer on earth, and its monomer N-acetylglucosamine (GlcNAc) not only has great application values in multiple areas, but also is a key intermediate for the conversion of chitin to other organonitrogen compounds. This review provides a comprehensive summary and perspective of the latest cutting-edge innovations on biomass conversion to GlcNAc. Biological methods, chemical methods as well as combined methods for GlcNAc preparation are systematically elaborated, and their respective advantages and disadvantages in terms of product yield, process safety, economy, efficiency, and environmental friendliness are discussed. To achieve an economic, environmentally friendly, and efficient production of GlcNAc from renewable biomass, the development of combined methods that involve multiple actions in a synergistic way under mild and green conditions should be the focus of future research. [ABSTRACT FROM AUTHOR]

Abstract: The methane potential of nine varieties of fresh maize harvested at three different times and of maize silage was experimentally determined in batch assays. The ultimate methane productivity in terms of volatile solids (VS) was determined as 213.94–313.63, 195.88–334.81mL/g VS from several fresh and silage maize in three stages, respectively. The average specific methane yield of wax ripeness stage for fresh maize and full ripeness stage for silage maize were higher than that of other stages, respectively. The high-oil varieties of fresh maize and silage varieties of ensiling maize could produce more methane than general varieties in the same ripeness stage. Methane yield of ensiled materials was higher than fresh material. The methane yields of fresh and silage maize in full ripeness stage were ranged 5656–7956 and 4633–8915m3/ha, respectively. The corresponding maximum of methane yield came from fresh HO5580 and silage CAU No. 4. [Copyright &y& Elsevier]

Arable (cereals, pulses and tubers) production has been the most important object of Chinese agriculture. China has long insisted on 'self-reliance on grain', often at the expense of resources and the environment. The impact of globalization and its entry into the World Trade Organization (WTO) require China to reorient its agriculture over the next two decades so that it is based on ecological and economic principles. The alternatives are: (1) to increase grain imports to about 10% of total consumption; (2) to develop horticulture, livestock and aquaculture with their greater comparative advantages; (3) to expand the notion of agriculture by, for example, developing 'energy farming'. The real future challenge for grain production will come from the rapid development of livestock production and its requirements, rather than growing edible grains for human consumption. To address this new type of livestock revolution, there will be a need to promote Chinese ecological agriculture (CEA) as well as to improve feed efficiency. The measures taken must focus on increasing farmers' incentives to help bring about the changes and on achieving the sustainable development of agriculture. [ABSTRACT FROM AUTHOR]

Abstract: The composite microbial system of MC1 was used to degrade corn stalk in order to determine properties of the degraded products as well as bacterial composition of MC1. Results indicated that the pH of the fermentation broth was typical of lignocellulose degradation by MC1, decreasing in the early phase and increasing in later stages of the degradation. The microbial biomass peaked on the day 3 after degradation. The MC1 efficiently degraded the corn stalk by nearly 70% during which its cellulose content decreased by 71.2%, hemicellulose by 76.5% and lignin by 24.6%. The content of water-soluble carbohydrates (WSC) in the fermentation broth increased progressively during the first three days, and decreased thereafter, suggesting an accumulation of WSC in the early phase of the degradation process. Total levels of various volatile products peaked in the third day after degradation, and 7 types of volatile products were detected in the fermentation broth. These were ethanol, acetic acid, 1,2-ethanediol, propanoic acid, butanoic acid, 3-methyl-butanoic acid and glycerine. Six major compounds were quantitatively analysed and the contents of each compound were ethanol (0.584 g/L), acetic acid (0.735 g/L), 1,2-ethanediol (0.772 g/L), propanoic acid (0.026 g/L), butanoic acid (0.018 g/L) and glycerine (4.203 g/L). Characterization of bacterial cells collected from the culture solution, based on 16S rDNA PCR-DGGE analysis of DNAs, showed that the composition of bacterial community in MC1 coincided basically with observations from previous studies. This indicated that the structure of MC1 is very stable during degradation of different lignocellulose materials. [Copyright &y& Elsevier]

5-Hydroxymethylfurfural (HMF), a versatile biomass derivative building block, is recognized as a bridge between biorefinery and petrorefinery for the production of sustainable fuels and chemicals. Despite extensive research, the industrial production of HMF is far from being realized. The design of novel systems for biomass processing should fully consider the properties of feedstocks and products, and only in this way can we realize the efficient and economical utilization of biomass on industrial scales. Here, we break through the limitations of traditional technologies and report a novel strategy with simple operation, high efficiency, and low cost for HMF production. By the simultaneous circulation of a reaction phase and an extraction phase, and the separation of a HMF extraction process from carbohydrate dehydration conditions, carbohydrates could be continuously and stably dehydrated to HMF in high yields. Over 94 mol% yield of HMF was obtained from fructose and nearly 70 mol% was obtained from glucose, both of which were significantly higher than all reported data obtained in water. Techno-economic analysis demonstrated that HMF could be produced at a minimum selling price of $1716 per ton and $1215 per ton from fructose and glucose, respectively, which brings hope and motivation for the commercial production of HMF. [ABSTRACT FROM AUTHOR]

Background: As a leading biomass feedstock, poplar plants provide enormous lignocellulose resource convertible for biofuels and bio-chemicals. However, lignocellulose recalcitrance particularly in wood plants, basically causes a costly bioethanol production unacceptable for commercial marketing with potential secondary pollution to the environment. Therefore, it becomes important to reduce lignocellulose recalcitrance by genetic modification of plant cell walls, and meanwhile to establish advanced biomass process technology in woody plants. Brassinosteroids, plant-specific steroid hormones, are considered to participate in plant growth and development for biomass production, but little has been reported about brassinosteroids roles in plant cell wall assembly and modification. In this study, we generated transgenic poplar plant that overexpressed DEETIOLATED2 gene for brassinosteroids overproduction. We then detected cell wall feature alteration and examined biomass enzymatic saccharification for bioethanol production under various chemical pretreatments. Results: Compared with wild type, the PtoDET2 overexpressed transgenic plants contained much higher brassinosteroids levels. The transgenic poplar also exhibited significantly enhanced plant growth rate and biomass yield by increasing xylem development and cell wall polymer deposition. Meanwhile, the transgenic plants showed significantly improved lignocellulose features such as reduced cellulose crystalline index and degree of polymerization values and decreased hemicellulose xylose/arabinose ratio for raised biomass porosity and accessibility, which led to integrated enhancement on biomass enzymatic saccharification and bioethanol yield under various chemical pretreatments. In contrast, the CRISPR/Cas9-generated mutation of PtoDET2 showed significantly lower brassinosteroids level for reduced biomass saccharification and bioethanol yield, compared to the wild type. Notably, the optimal green-like pretreatment could even achieve the highest bioethanol yield by effective lignin extraction in the transgenic plant. Hence, this study proposed a mechanistic model elucidating how brassinosteroid regulates cell wall modification for reduced lignocellulose recalcitrance and increased biomass porosity and accessibility for high bioethanol production. Conclusions: This study has demonstrated a powerful strategy to enhance cellulosic bioethanol production by regulating brassinosteroid biosynthesis for reducing lignocellulose recalcitrance in the transgenic poplar plants. It has also provided a green-like process for biomass pretreatment and enzymatic saccharification in poplar and beyond. [ABSTRACT FROM AUTHOR]

Bioenergy will play an intimate and critical role in energy supply and carbon mitigation in the future. In recent years, "customizing the development of bioenergy to local conditions" and "prioritizing distributed utilization" have been the two key principles that have been released by the Chinese government to promote the national‐ and provincial‐level development of bioenergy. While many recognize the importance of bioenergy in achieving low‐carbon transition, little is known about the high‐resolution distribution of usable biomass feedstock and technical bioenergy potential in China, which brings about uncertainties and additional challenges for creating localized utilization plans. We propose a new assessment framework that integrates crop growth models, a land suitability assessment, and the geographic information systems to address these knowledge gaps. Distributions of 11 types of usable biomass feedstock and three kinds of technical bioenergy potential are mapped out through specific transformation technologies at 1 km resolution. At the national level, the final technical biogas potential is 1.91 EJ. The technical bioethanol potential (0.04–0.96 EJ) from the energy crop can supply 0.13–3.12 times the bioethanol demand for the consumption of E10 gasoline in 2015. The technical heat potential (1.06 EJ) can meet 20% of the demand for heating in all provinces (5.38 EJ). Most of the 2020 bioenergy goals can be achieved, excluding that for bioethanol, which will need to require more cellulosic ethanol from residues. At the provincial level, Henan and Inner Mongolia have the potential to develop clean heating alternatives via the substitution of agroforestry residues for coal. The results can provide a systematic analysis of the distribution of biomass feedstocks and technical bioenergy potential in China. With economic factors taken into consideration in further research, it can also support national and provincial governments in making bioenergy development plans in an effective and timely manner. [ABSTRACT FROM AUTHOR]

The development of a highly active and robust catalyst for the conversion of lignin, the largest volume of renewable aromatic resource in nature, to value-added aromatics is of great importance in sustainable chemistry. However, the condensation of lignin depolymerization intermediates into recalcitrant macromolecules restricts high yields of desired products, and this remains a great challenge in lignin valorization. Here, a serious of bifunctional Ru–ZnO/SBA-15 catalysts were synthesized for lignin conversion to aromatics. Roles of Ru and ZnO in these catalysts for lignin conversion were in-depth analyzed. The effect of the ratio of Ru to ZnO was studied. Other reaction conditions including temperature and time were systematically optimized. More than 51.3% yields of aromatics were obtained over Ru–10ZnO/SBA-15 at 240 °C for 4 h. Structure-activity relationship research of the catalyst revealed that the high yield of product could be attributed to the following three reasons: 1) the Lewis acidic sites on Ru/SBA-15 are significantly improved after ZnO modification, and thus promotes the C–O bond cleavage; 2) the oxophilic ZnO is beneficial to absorb the substrate and reaction intermediates, and therefore enhances the hydrodeoxygenation activity of the adjacent Ru; 3). The interaction between Zn and Ru in Ru–ZnO/SBA-15 changes Ru electronic properties and leads to the formation of highly active catalytic sites with high electron density. These results indicated that the bifunctional Ru–ZnO/SBA-15 catalyst with high catalytic activity could be a good choice for lignin conversion to high-yield aromatics. [Display omitted] [ABSTRACT FROM AUTHOR]

Compressed bio-natural gas (CBG) production from large-scale systems has been recognized as promising because of the abundance of manure and crop residue feedstocks and its environmental friendliness. This study is a life cycle assessment using the local database of an operating large-scale CBG system of manure co-digestion with corn stover in China and eBalance software. The results showed that the system's Primary Energy Input to Output (PEIO) ratio was 20%. Its anaerobic digestion process was the main contributor to energy consumption, accounting for 76%. Among the six environmental impacts investigated in this study, the global warming potential (GWP) was the major environmental impact, and the digestate effluent management process was the main contributor to the GWP, accounting for 60%. The mitigation potential of the system, compared with reference case for GWP, was 3.19 kg CO2-eq for 1 m3 CBG production. In the future, the GWP mitigation could be 479 × 106 metric tons CO2-eq with 150 × 109 m3 yr−1 CBG production from the entire China. This study provides a reference on large-scale CBG production system for establishing a localized life cycle assessment inventory database in China. [ABSTRACT FROM AUTHOR]

A composted material derived from biogas production residues, spent mushroom substrate (SMS) and pig manure was evaluated as a partial or total replacement for peat in growth medium for tomato and pepper seedlings. Five different substrates were tested: T1, compost + perlite (5:1, v:v); T2, compost + peat + perlite (4:1:1, v:v:v); T3, compost + peat + perlite (2.5:2.5:1, v:v:v); T4, compost + peat + perlite (1:4:1, v:v:v); and CK, a commercial peat + perlite (5:1, v:v). The physical-chemical characteristics of the various media were analyzed, and the germination rate and morphological growth were also measured. Real-time Quantitative PCR (qPCR) was used to quantify Fusarium concentrations. The addition of compost to peat-based growth medium increased the pH, electrical conductivity, air porosity, bulk density, and nutrition (NPK), and decreased the water holding capacity and total porosity. The use of compost did not affect the percent germination at day 15 of the tomato and pepper seedlings. The addition of compost resulted in better or comparable seedling quality compared with CK and fertilized CK. The best growth parameters were seen in tomato and pepper seedlings grown in T1 and T2, with higher morphological growth in comparison with CK and fertilized CK. However, T2 showed the highest Fusarium concentration compared to compost and all growth media. Fusarium concentrations in T1, T3, and T4 did not differ significantly from those in CK for tomato seedlings, and those in T1 and T4 were also similar to those in CK for pepper seedlings. The results suggest that biogas residues and SMS compost is a good alternative to peat, allowing 100% replacement, and that 20–50% replacement produces tomato and pepper seedlings with higher morphological growth and lower Fusarium concentrations. [ABSTRACT FROM AUTHOR]

In this study, the impact of pig manure on the maturity of compost consisting of spent mushroom substrate and rice husks was accessed. The results showed that the addition of pig manure (SMS-PM) reached 50 °C 5 days earlier and lasted 15 days longer than without pig manure (SMS). Furthermore, the addition of pig manure improved nutrition and germination index. High-throughput 16S rRNA pyrosequencing was used to evaluate the bacterial and fungal composition during the composting process of SMS-PM compared to SMS alone. The SMS treatment showed a relatively higher abundance of carbon-degrading microbes (Bacillaceae and Thermomyces ) and plant pathogenic fungi (Sordariomycetes_unclassified) at the end of the compost. In contrast, the SMS-PM showed an increased bacterial diversity with anti-pathogen ( Pseudomonas ). The results indicated that the addition of pig manure improved the decomposition of refractory carbon from the spent mushroom substrate and promoted the maturity and nutritional content of the compost product. [ABSTRACT FROM AUTHOR]

Ensilage is a commonly used method of preserving energy crops for biogas production. However, aerobic deterioration of silage is an inevitable problem. This study investigated the effect of aerobic deterioration on methane production and microbial community dynamics through anaerobic digestion (AD) of maize stalk silage, following 9 days air exposure of silage. After air exposure, hydrolytic activity and methanogenic archaea amount in AD were reduced, decreasing the specific methane yield (SMY); whereas lignocellulose decomposition during exposure improved the degradability of silage in AD and enhanced SMY, partially compensating the dry matter (DM) loss. 29.3% of the DM and 40.7% of methane yield were lost following 0–9 days exposure. Metagenomic analysis showed a shift from Clostridia to Bacteroidia and Anaerolineae in AD after silage deterioration; Methanosaetaceae was the dominant methanogenic archaea. [ABSTRACT FROM AUTHOR]

Fe is widely used as an additive in anaerobic digestion, but its bioavailability and the mechanism by which it enhances digestion are unclear. In this study, sequential extraction was used to measure Fe bioavailability, while biochemical parameters, kinetics model and Q-PCR (fluorescence quantitative PCR) were used to explore its mechanism of stimulation. The results showed that sequential extraction is a suitable method to assess the anaerobic system bioavailability of Fe, which is low and fluctuates to a limited extent (1.7 to –3.1 wt%), indicating that it would be easy for Fe levels to be insufficient. Methane yield increased when the added Fe 2+ was 10–500 mg/L. Appropriate amounts of Fe 2+ accelerated the decomposition of rice straw and facilitated methanogen metabolism, thereby improving reactor performance. The modified Gompertz model better fitted the results than the first-order kinetic model. Feasibility analysis showed that addition of Fe 2+ at ≤50 mg/L was suitable. [ABSTRACT FROM AUTHOR]

Molasses is a typical feedstock for fermentation, but the effluent is hard to treat. In this study, molasses containing a high concentration of organic matter was treated by a two-stage Fix-bed reactor system with an increased organic loading rate (OLR). The results indicated at high molasses loading rate, the two-stage system was more efficient (i.e. organic matter removal, the COD of effluent and biogas production) than the single-stage system. The relative abundance of Anaerolineaceae and W5_norank was higher in the first stage (R1), where these organisms digest carbohydrates, while the second stage (R2) had higher relative abundance of Synergistaceae and SB-1_norank , which digest VFAs and decomposition-resistant compounds to produce compounds used by hydrogen methanogens. The qPCR analysis demonstrated that the Methanosaetaceae dominated the archaeal community in the first stage (R1), while Methanomicrobiales and Methanobacteriales were predominant in the second stage (R2), where they were involved in hydrogen production. [ABSTRACT FROM AUTHOR]

Although trace elements are known to aid anaerobic digestion, their mechanism of action is still unclear. High-throughput sequencing was used to reveal the mechanism by which adding trace elements affects microbial communities and their action. The results showed that the highest methane yields, with addition of Fe, Mo, Se and Mn were 289.2, 289.6, 285.3, 293.0 mL/g volatile solids (VS), respectively. The addition of Fe, Mo, Se and Mn significantly ( P < 0.05) reduced the level of volatile fatty acids (VFAs). The dominant bacteria and archaea were Bacteroidetes and Methanosaeta , respectively. Compared with the proportion of Methanosaeta in the control group, treatment with added trace elements increased Methanosaeta by as much as 12.4%. Microbial community analysis indicated that adding trace elements changed the composition and diversity of archaea and bacteria. Methane yield was positively correlated with bacterial diversity and negatively correlated with archaeal diversity for most treatments. [ABSTRACT FROM AUTHOR]

The ready formation of scum in vertical reactors has been a bottleneck in the digestion of lignocellulosic materials for biogas production. This study describes a single vertical reactor that integrates the acidogenic and methanogenic phases of this process. The effects of two types of maize stover feedstock (fresh and silage) and two mixing intensities (20 and 70 rpm) on methane yield were orthogonally determined. Fresh maize stover yielded approximately 14% more methane than silage maize stover. Mixing at 20 rpm contributed to methane yield, while mixing at 70 rpm blurred the phase boundary, resulting in accumulation of volatile fatty acids and loss of methanogens. The upper and lower phases clearly constituted a two-phase fermentation system. Clostridiales occupied the acidogenic phase, while the predominant bacteria in the methanogenic phase were Bacteroidetes , Chloroflexi , and Synergistetes . The absolute predominance of Methanosaetaceae clearly demonstrated that aceticlastic methanogenesis was the main route of methane production. [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd NPs are highly dispersed on defective Al-metal organic framework via a facile method. • Missing linker defects produce coordinatively unsaturated metal sites (CUMSs) as catalytic sites. • Defects enhance the catalyst acidity and improve catalytic activity. • Defect engineering of MOFs opens up novel opportunities for lignin valorization. • DFT calculations revealed that the HDO of vanillin underwent a cascade of hydrogenation-hydrogenolysis routes. Designing highly active catalysts for selective hydrodeoxygenation (HDO) of lignin-derived oxygenates into well-defined compounds is of great importance for realizing high-value utilization of lignin. Defect engineering in metal–organic frameworks (MOFs) is an emerging concept for tailoring MOF properties, which might be a promising strategy in the synthesis of high-performance catalysts. Herein, we developed a facile synthetic strategy by adding trifluoroacetic acid as the modulator to prepare a bifunctional catalyst (Pd/NH 2 -MIL-53-d) consisting of Pd nanoparticles highly dispersed on defective NH 2 -MIL-53(Al). Characterizations, including TEM, XRD, IR, XPS and NH 3 -TPD, were employed to reveal the morphology and physicochemical properties of the catalysts. Results indicated that the introduction of defects leads to the generation of coordinatively unsaturated metal sites, which can act as anchor points for high-dispersion of Pd nanoparticles and as additional active acid sites for catalytic reactions. 100% conversion of vanillin and other 8 representative derivates of lignin into their decarbonyl products with yields over 99% has been achieved under mild conditions in the water. Density functional theory calculations revealed that the HDO of vanillin into 2-methoxy-4-methylphenol mainly underwent a cascade of hydrogenation-hydrogenolysis routes, and the synergistic interaction between Pd and defective NH 2 -MIL-53(Al) facilitated the novel bifunctional catalyst to exhibit outstanding catalytic performance. No apparent deactivation of the catalyst was noticed after it was reused 5 times. Therefore, engineering of defects in MOFs holds enormous potential in designing novel bifunctional catalysts for lignin valorization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mild pretreatments for near-complete saccharification of desirable lignocelluloses. • Integrated green-like biomass pretreatments to achieve maximum cellulosic ethanol. • Green-like pretreatments selectable for generation of nanomaterials and nanocarbon. • Distinct pretreatment mechanisms accounting for biomass recalcitrance reduction. • A novel strategy for cost-effective biofuels and functional materials at high value. Lignocellulose represents the most abundant carbon-capturing substance that is convertible for biofuels and bioproduction. Although biomass pretreatments have been broadly applied to reduce lignocellulose recalcitrance for enhanced enzymatic saccharification, they mostly require strong conditions with potential secondary waste release. By classifying all major types of pretreatments that have been recently conducted with different sources of lignocellulose substrates, this study sorted out their distinct roles for wall polymer extraction and destruction, leading to the optimal pretreatments evaluated for cost-effective biomass enzymatic saccharification to maximize biofuel production. Notably, all undigestible lignocellulose residues are also aimed for effective conversion into value-added bioproduction. Meanwhile, desired pretreatments were proposed for the generation of highly-valuable nanomaterials such as cellulose nanocrystals, lignin nanoparticles, functional wood, carbon dots, porous and graphitic nanocarbons. Therefore, this article has proposed a novel strategy that integrates cost-effective and green-like pretreatments with desirable lignocellulose substrates for a full lignocellulose utilization with zero-biomass-waste liberation. [ABSTRACT FROM AUTHOR]

Pretreatment is a key step for the conversion of lignocellulosic biomass to biomethane via anaerobic digestion (AD). Though various chemical pretreatment strategies have been developed, most of them are costly and environmentally unfriendly, which seriously prevents them from practical applications. This study provides an innovative strategy that uses two kinds of AD byproducts, i.e., CO 2 and acidogenesis liquid digestate (ALD), to replace conventional chemical reagents for pretreating corn stover. The effect of CO 2 -ALD pretreatment at different temperatures (35, 55, and 100 °C) on biomethane production as well as characteristics of pretreated solid and liquid products were studied. Results showed that the highest biomethane yield was obtained after using 1 Mpa CO 2 in ALD at 55 °C pretreatment, which was 63.85% higher than the untreated sample. Meanwhile, CO 2 -ALD pretreatment could destroy the stubborn structure of lignocellulose and separate partially cellulose and hemicellulose, from the stover. The microbial community analysis indicated that this pretreatment strategy enhanced the abundance of hydrolytic bacteria and promoted the acetotrophic pathway. Further energy balance analysis proved that using 1 Mpa CO 2 in ALD at 55 °C for pretreatment had the highest energy gain (E out /E in), which was 30.51 % higher than that without any pretreatment. [Display omitted] • Acidogenesis liquid digestate and carbon dioxide were used to pretreat corn stover. • The stubborn obstruction of lignocellulose was eliminated after pretreatment. • A 63.85 % methane enhancement was achieved by this pretreatment. • Microbial community changes revealed that the acetotrophic pathway was promoted. • The energy ratio increased by 30.51 % under the best pretreatment conditions. [ABSTRACT FROM AUTHOR]

A series of 2D sheet Bi2OxS3−x/Nb6O17 (Bi/Nb) heterostructure photocatalysts were synthesized through a facile hydrothermal vulcanization method between Bi3+ exchanged K4Nb6O17 and thiourea (NH2CSNH2). XRD results confirm that the heterostructures were composed of Bi2OxS3−x and Nb6O17. HRTEM indicates that Bi2OxS3−x was successfully intercalated into layers of K4Nb6O17. Such large interfacial contacts can be beneficial to the transfer and separation of photogenerated charge carriers. Thus the composites exhibit good photocatalytic performance for the degradation of methyl orange (MO) under visible light irradiation (λ ＞ 400 nm), which is superior to that of both precursors, pure Bi2S3 and K4Nb6O17. Radical capture tests reveal that photogenerated holes h+ and ṖO2− play important roles in the photodegradation of MO. And based on the UV-visible diffuse reflectance spectra (DRS) and the band gap of the semiconductors, the mechanism of the enhanced visible light photocatalytic activity of these composites has been proposed. [ABSTRACT FROM AUTHOR]

Bioaugmentation using microbial consortia is helpful in some anaerobic digestion (AD) systems, but accelerated acidification to produce methane has not been performed effectively with corn stalks and cow dung. In this study, the thermophilic microbial consortia MC1 was inoculated into a complex open environment (unsterilized and sterilized systems) to evaluate the feasibility of bioaugmentation to improve acidification efficiency. The results indicated that MC1 itself degraded lignocellulose efficiently, and accumulated more organic acids within 3 days. Similar trends were also observed in the unsterilized system, where the hemicellulose degradation rate and organic acid concentrations increased significantly by two-fold and 20.1% (P < 0.05), respectively, and clearly reduced the loss of product. Microbial composition did not change obviously after inoculating MC1, but the abundance of members of MC1, such as Bacillus and Clostridium , increased clearly on day 3. Finally, the acidogenic fluid improved methane yield significantly (P < 0.05) via bioaugmentation. [ABSTRACT FROM AUTHOR]

Adopting anaerobic digestion (AD) of lignocellulosic biomass to produce biomethane is an effective approach to meet the urgent demand for clean and sustainable energy in energy transition. The pretreatment kinetic mechanism is the key to enhance the lignocellulosic carbon conversion and significantly improve the efficiency of AD. Various pretreatment strategies have been proposed in the literature, while a systematical summarization of these strategies based on different driving forces is still lacking. The purpose of this review is to classify and analyze the current technologies and research achievements on lignocellulose pretreatment technologies according to different driving forces including single ones and combined ones. Features, as well as fundamental modes of conventional and recently emerged pretreatments, have been introduced. Single pretreatment methods driven by physical, chemical, or biological forces have obvious advantages and limitations for the anaerobic transformation of lignocellulosic feedstocks. Recently emerged combined pretreatment technologies powered by multiple forces have synergistic treatment effects which hold greater application potential than those driven by single forces. Besides, a comprehensive evaluation of combined pretreatments is carried out on the basis of pretreatment efficiency, cost, energy consumption, and environmental impact to detect their potential applications in the actual biogas industry. By comprehensively summarizing the current features of single and combined technologies, this review finally provides future research perspectives for biomass pretreatment. [Display omitted] • Features of different pretreatments driving by different forces were analyzed. • Conventional pretreatments driven by single forces have obvious shortcomings. • Rational integration of multiple driving forces has synergistic pretreatment effect. • Combined pretreatment strategies have greater potential than single ones. • Physical-chemical methods are most promising based on comprehensive evaluations. [ABSTRACT FROM AUTHOR]

The methane yield and microbial community resulting from co-digestion of dairy manure and switchgrass at different mixing ratios [4:0, 3:1, 2:2, 1:3, and 0:4 based on total solids (TS) content] were evaluated. The results indicated that switchgrass is an excellent feedstock for biogas production when co-digested with dairy manure. Mono-digestion of a high dose (>4% TS) of switchgrass led to volatile fatty acid accumulation and process failure, whereas co-digestion of switchgrass and dairy manure could increase the buffering capacity and improve the fermentation efficiency. The optimal mixture ratio of dairy manure and switchgrass was 2:2, with a methane yield that was 39% higher than that obtained by digestion of the individual substrates. The added amount of 8% TS at the 2:2 ratio achieved the highest methane yield of 158.6 mL/g VS, which corresponded to a 1.3-fold increase in the volumetric productivity of methane compared to mono-digestion of 4% TS switchgrass. Quantitative polymerase chain reaction and clone library analyses showed significant differences in the bacterial community resulting from the different co-substrate ratios. Planctomycetes (28%), Chloroflexi (24%), and Bacteroidetes (24%) were the dominant phyla in digesters with a co-substrate ratio of 2:2. [ABSTRACT FROM AUTHOR]

Methane production from lignocellulosic feedstock through high solid anaerobic digestion is a huge potential technology. However, the shortage of an efficient reactor has become a major bottleneck in developing the technology. The continuous feeding and discharge of lignocellulosic feedstock with high solids is difficult to complete. Methane production from the feedstock is low in practice. Thus, it is important to develop a new reactor with efficient feeding and discharge feedstock equipments and improve methane production by an optimized operation process. Based on synthesizing the merits of a number of techniques home and abroad, a novel anaerobic reactor was designed in this study. The reactor had two spiral equipments to implement continuous feeding and discharge feedstock with high solid content and had a high bearing capability of organic loading rate (OLR) to improve methane production. In order to provide a technology and some reliable operating parameters to efficiently produce methane from lignocellulosic feedstock, the continuous anaerobic co-digestion tests were conducted at three total solid contents of 10%, 15% and 20% using corn stalk and dairy manure as feedstock. An integrated two-phase division digestion system was constructed by controlling stirring intensity (h/d) and feeding intensity (d). The methane volumetric production rate (MVPR) of different OLRs was compared. Effects of the total solid (TS) of feedstock, stirring, feeding intensity on height, pH of function divisions, and MVPR were discussed in detail. The results showed that function divisions, including the acidification division of upside and methanogenic division of underpart in the vertical reactor, were obviously formed when TS were 10% and 15%, MVPR gradually increased, and methane content stabilized around 52% with OLR increasing. The highest MVPR reached 1.62 and 1.66 m3/(m3·d) respectively when OLR was 13.44 kg/(m3·d) at 10% TS and 20.17 kg/(m3·d) at 15% TS. MVPR significantly decreased when OLR was 20.17 kg/(m3·d) and 30.0 kg/(m3·d), respectively, which might be caused by the accumulation of volatile fatty acids. MVPR stabilized around 0.98 m3/(m3·d) with OLR increasing, then it dramatically decreased and anaerobic digestion failed when OLR reached 30.0 kg/(m3·d) at 20% TS. The results of two factors interacting declared the highest MVPR at 1.63-1.69 m3/(m3·d) The efficient acidification division and methanogenic division were formed, and the height ratio of both was 1.1-1.6:1 when stirring intensity, feeding intensity, and TS were 6-12 h/d, 6.5-10 d, and 10%-15%, respectively. In summary, the process of continuous feeding and discharge at 10%-20% TS of lignocellulosic feedstock was feasible in the anaerobic digestion reactor. The reactor was more efficient and stable to produce methane at 10% and 15% TS compared to 20% TS, and MVPR could be improved by adjusting stirring intensity and feeding intensity. Therefore, this technology has a promising prospect for industrial scale application. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effect of microbial pretreatment on methane production of LMSW was evaluated. [•] Soluble substrates in hydrolysate increased obviously after microbial pretreatment. [•] CH4 production yields and rates significantly increased after microbial pretreatment. [Copyright &y& Elsevier]

Correction for 'N-acetylglucosamine as a platform chemical produced from renewable resources: opportunity, challenge, and future prospects' by Shuling Cao et al., Green Chem., 2022, 24, 493–509, DOI: 10.1039/D1GC03725K. [ABSTRACT FROM AUTHOR]

[Display omitted] • Anaerobic digestion by-products were used to pretreated corn straw. • Methane production was improved by 50.97% after CO 2 -liquid digestate pretreatment. • The dense structure of straw could be effectively destroyed after pretreatment. • Pretreatment at 170 ℃ hindered methane production due to formation of inhibitors. • Mechanism behind CO 2 -liquid digestate pretreatment was elucidated. The development of biogas projects feed by lignocellulosic biomass has been constrained by the high cost of pre- and post-treatment. In this study, a novel strategy for pretreatment by using two by-products, i.e., CO 2 and liquid digestate (LD), generated from anaerobic digestion (AD) was developed to overcome these shortcomings. Results showed that corn straw pretreated in LD pressurized under 1 Mpa CO 2 at 55 ℃ resulted in increased glucose and xylose contents and a 9.80% decrease in cellulose crystallinity. After 45 days of AD conversion, the methane yield increased by 50.97% compared with untreated straw. However, pretreatment in LD pressurized under 1 Mpa CO 2 at 170 ℃ produced 5-hydroxymethylfurfural and furfural, which led to a decrease in methane production from the straw in the subsequent AD conversion. The alteration of the microbial community in the pretreated slurry at 55 °C was another potential contributor to the enhanced performance of AD. [ABSTRACT FROM AUTHOR]

Highlights: [•] Stepwise increase of OLR concentration for four anaerobic reactors impact ability and threshold. [•] Fixed-bed anaerobic reactor biological parameter dynamics using quantitative methods. [•] Main bacteria functional groups identified as bacteroidetes bactericum and uncultured chloroflexi bacterium. [•] Main archaea functional groups identified as methanomicrobiales. [ABSTRACT FROM AUTHOR]

Abstract: A microbial consortium MC1 was used to pretreat filter paper, office paper, newspaper, and cardboard to enhance methane production. The results of pretreatment indicated that sCOD of hydrolysates of the four substrates increased significantly in the early stage, and peaked on day 7. During pretreatment, ethanol, acetic acid, propionic acid, butyric acid, and glycerol were the predominant volatile organic products in hydrolysates. MC1 had strong degradation ability on the four substrates, and the weight loss of filter paper, office paper, newspaper, and cardboard reached 78.3%, 80.5%, 39.7%, and 49.7%, respectively. The results of anaerobic digestion showed that methane production yields and rates of the four substrates significantly increased after pretreatment. This study is the first attempt to explore the microbial pretreatment method for anaerobic digestion of waste paper and cardboard. Microbial consortium pretreatment could be an effective method for enhancing methane production of waste paper and cardboard into bioenergy. [Copyright &y& Elsevier]

Along with the development of the starch and grain-alcohol industries, biomass energy production has recently become important. Cassava is an important biomass energy plant. In this paper, geographic information system (GIS) and remote sensing (RS) are used, along with a knowledge of the growing environment needed for cassava and the farmland and ecology protection policy of China, to evaluate the cassava growing potential of Wuming County. The processing of spatial data is done first. Then, the evaluation principles are defined according to the spatial data and the required growth conditions. The evaluation data are obtained by spatial data analysis according with the evaluation principles. Lastly, the cassava planting potential results are verified by referencing these to cassava planting statistical data for 2005 provided by Nanning City Government of Guangxi province. This paper provides the science basis for Wuming County to develop local grain-alcohol and biomass energy industries. [ABSTRACT FROM AUTHOR]

The biomethane production from lignocellulose via anaerobic digestion has always suffered from low carbon conversion rate, due to the stubborn structure of lignocellulose and the inefficiency of the current anaerobic digestion systems. The integrated two-phase anaerobic reactor can form a highly efficient anaerobic digestion system with an upper acidogenic phase and a lower methanogenic phase. However, the acidogenic phase can be overaccelerated, leading to acidification failure of the whole digestion system. In this study, the acidogenesis liquid digestate (ALD) generated from the acidogenic phase was applied to impregnate corn straw coupled with disc refining (DR) to enhance biomethane production by forming a thorough and stable integrated two-phase anaerobic system. The concentration of volatile fatty acids in the acidogenic phase is adjusted by this pretreatment technology to approximately match the efficiency of methanogenic bacteria in the methanogenic phase. The acetic acid in ALD was proved to be an effective acid to swell lignocellulose and improved the performance of the acid impregnation coupled with disc refining (AIDR) pretreatment. A 47.13% higher biomethane yield was obtained from corn straw after AIDR pretreatment. Moreover, energy conversion efficiency and economic analysis indicated this anaerobic digestion process with AIDR pretreatment had a $ 21.06 ton−1 higher net profit than that without any pretreatment. This novel anaerobic digestion process creates a synergistic processing technology that integrates biomass pretreatment with a two-phase anaerobic digestion system, resulting in destroying the compact structure of lignocellulose, enhancing biomethane production efficiency, and improving the economic competitiveness of biomass conversion to biomethane. [Display omitted] • A strategy integrated pretreatment and two-phase anaerobic digestion was unveiled. • Acid impregnation coupled with disc refining was used to pretreat corn straw. • Biomethane production was improved by 47.13% after employing the novel strategy. • Mechanism for improving biomethane production by the novel strategy was elucidated. [ABSTRACT FROM AUTHOR]

Improving biomass enzymatic saccharification is effective for crop straw utilization, whereas phytoremediation is efficient for trace metal elimination from polluted agricultural soil. Here, we found that the green proteins extracted from Amaranthus leaf tissue could act as active biosurfactant to remarkably enhance lignocellulose enzymatic saccharification for high bioethanol production examined in eight grassy and woody plants after mild chemical and green-like pretreatments were performed. Notably, this study estimated that total green proteins supply collected from one-hectare-land Amaranth plants could even lead to additional 6400–12,400 tons of bioethanol, being over 10-fold bioethanol yield higher than those of soybean seed proteins and chemical surfactant. Meanwhile, the Amaranth green proteins were characterized as a dominated biosorbent for multiple trace metals (Cd, Pb, As) adsorption, being 2.9–6 folds higher than those of its lignocellulose. The Amaranth plants were also assessed to accumulate much more trace metals than all other plants as previously examined from large-scale contaminated soils. Furthermore, the Amaranth green proteins not only effectively block lignin to release active cellulases for the mostly enhanced biomass hydrolyzes, but also efficiently involve in multiple chemical bindings with Cd, which should thus address critical issues of high-costly biomass waste utilization and low-efficient trace metal remediation. ga1 • Amaranth green proteins act as universal biosurfactant for biomass lignin blocking. • Enhanced saccharification of diverse biomass residues by green proteins supply. • Green proteins paly a dominated biosorbent role for three trace metals adsorption. • Amaranth plants accumulate much more trace metals than all other plants from lands. • Green proteins involve in multiple chemical interlinking with Cd for adsorption. [ABSTRACT FROM AUTHOR]

[Display omitted] Ca(OH) 2 induces a controlled-release catalytic system for the efficient conversion of high-concentration glucose to relatively high yield of lactic acid under mild conditions. • High concentration of glucose was converted to high yield of lactic acid (LA). • Ca(OH) 2 formed a controlled release catalytic system for glucose conversion to LA. • Ba(OH) 2 played a synergistic effect with Ca(OH) 2 in glucose conversion to LA. • Over 40 % yield of LA was obtained from high concentration of glucose (>0.5 M). The catalytic conversion of carbohydrate to platform chemicals, e.g. lactic acid (LA), is the key to unlock the potential of biomass. In this study, we report that the combination of Ba(OH) 2 and Ca(OH) 2 can efficiently catalyse high-concentration (> 0.5 M) of glucose to relatively high yield of LA (> 40 %) under mild conditions (60 °C). Both glucose conversion and LA yield were sensitive to the pH of the catalytic system. A high loading of Ba(OH) 2 led to a high initial pH of the reaction solution, resulting in serious side reactions. While, a low loading of Ba(OH) 2 led to a quike decrease of OH− and Ba2+ both of which were continuously consumpted by the formed LA. The combination of Ca(OH) 2 with Ba(OH) 2 could significantly improve LA yield, since Ca(OH) 2 , with limited solubility, could act as a controlled-release catalyst for the real-time supply of OH− and Ca2+. OH− was indispensable for glucose isomerization to fructose as well as for fructose retro-aldol reaction to C 3 intermediates. Ca2+ could combine with LA to form stable calcium lactate, liberating Ba2+ to catalyse the conversion of C 3 intermediates to LA. Under the preliminary optimized reaction conditions, the yield of LA could be reached to 42.55 % and 38.32 % from 0.5 M and 1 M glucose, respectively. This catalytic system has advantages of mild reaction condition, short reaction time, and capable of conversion of high-concentration substrates, enabling it with a great potential for practical applications. [ABSTRACT FROM AUTHOR]

The selection of a suitable catalytic system for ligninOX reductive depolymerization, with a careful consideration of the reaction conditions and catalyst compositions, is crucial to successful implementation of the oxidation–reduction strategy for lignin conversion. • 43% yields of aromatics were obtained from ligninOX, while only 11% were from lignin. • High hydrogen pressure is not beneficial to the conversion of ligninOX. • Catalysts with high hydrogenation activities tend to reconvert ligninOX to lignin. • LigninOX conversion pathways under different conditions were determined. Recently, a two-step strategy involving oxidative activation and reductive depolymerization becomes very popular for lignin conversion. However, both positive and negative results are obtained, and the detailed mechanism is still unknown. This study thoroughly investigated the effects of several key factors, including hydrogen pressure, reaction temperature, and catalyst compositions, on the reductive conversion of oxidized lignin (ligninOX) to aromatics. For lignin oxidative activation, FT-IR, 2D NMR, and TG/DTG were used to prove that hydroxyl groups at lignin side chains had been successfully oxidized to carbonyl groups by AcNH-TEMPO/HNO 3 /HCl system. For ligninOX reductive conversion, pathways and mechanisms were explored, and the applicable conditions of this strategy were determined. Under relative moderate hydrogen pressure (e.g. 2 Mpa) over metal–acid catalysts, e.g. Ru/γ-Al 2 O 3 combined with Hf(OTf) 4), an obvious advantage of ligninOX conversion was found. Yield of valuable product from ligninOX was 42.98% which was much higher than that (10.99%) from unoxidized lignin. While, under high hydrogen pressure or promoted by catalysts with high hydrogenation activities, ligninOX tended to be reconverted to original lignin structures with loss of its conversion advantage. 2-phenoxyacetophenone as a ligninOX model was used to verify this speculation and to predict reaction pathways over different catalytic systems. These results proved that a catalyst with both hydrogenolysis and hydrolysis activity was essential for efficient ligninOX depolymerization. [ABSTRACT FROM AUTHOR]

Abstract: A microcavity organic light-emitting diode (MOLED) was developed to emit white light. The MOLED was fabricated with a simple structure of glass/dielectric mirror/ITO/NPB/Alq/MgAg. White light was observed due to the emission of two cavity modes despite only one emitter layer. By well adjusting the resonance wavelength (488 and 612nm) and intensity, the two cavity modes give rise to a bright, white electroluminescene emission with a maximum luminance of 16435cd/m2, maximum luminous efficiency of 11.1cd/A. The MOLED has a CIE chromaticity coordinate of (0.32 and 0.34), which is very stable under the different applied voltage. [Copyright &y& Elsevier]