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• Rice straw-derived dissolved organic matter (DOM) included four main components. • The presence of goethite significantly promotes the straw decomposition process. • OM's adsorption capacity for Cd increased with the straw decomposition time. • The presence of minerals promoted the OM's adsorption capacity and affinity of Cd. • Surface precipitation and complexation dominant Cd adsorption by OM. Organic matter (OM) derived from the decomposition of crop residues plays a key role as a sorbent for cadmium (Cd) immobilization. Few studies have explored the straw decomposition processes with the presence of minerals, and the effect of newly generated organo-mineral complexes on heavy metal adsorption. In this study, we investigated the variations in structure and composition during the rice straw decomposition with or without minerals (goethite and kaolinite), as well as the adsorption behavior and mechanisms by which straw decomposition affects Cd immobilization. The degree of humification of extracted straw organic matter was assessed using excitation-emission matrix (EEM) fluorescence and Ultraviolet-visible spectroscopy (UV-vis), while employing FTIR spectroscopy and XPS to characterize the adsorption mechanisms. The spectra analysis revealed the enrichment of highly aromatic and hydrophobic components, indicating that the degree of straw decomposition and humification were further intensified during incubation. Additionally, the existence of goethite (SG) accelerated the humification of OM. Sorption experiments revealed that the straw humification increased Cd adsorption capacity. Notably, SG exhibited significantly higher adsorption performance compared to the organic matter without minerals (RS) and the existence of kaolinite (SK). Further analysis using FT-IR spectroscopy and XPS verified that the primary mechanisms involved in Cd immobilization were complexion with —OH and —COOH, as well as the formation of Cd-π binds with aromatic C=C on the surface of solid OMs. These findings will facilitate understanding the interactions of the rice straw decomposing with soil minerals and its remediation effect on Cd-contaminated farmland. [Display omitted] [ABSTRACT FROM AUTHOR]

Agricultural films, essential to contemporary agricultural production, are mostly made from non - biodegradable petroleum-based materials. The use of such films, especially in high-temperature environments, contributes to elevated internal temperatures in direct sunlight, adversely affecting crop appearance and quality. In this work, rice straw was used as the raw material to prepare biodegradable chemically crosslinked regenerated cellulose aerogel films (RCAF-CC) by combining physical dissolution regeneration, chemical cross-linking, and freezedrying. The resulting RCAF-CC is notable for its high middle-infrared emissivity and high solar reflectivity, which significantly aid in thermal dissipation for agricultural mulch by enhancing infrared radiation and solar reflection. Compared to traditional polyethylene films, RCAF-CC, with its superior radiative cooling properties and lower water vapor transport rate, has a significant advantage in the growth trend and survival rate of cherry radishes. It is worth noting that the RCAF-CC achieved the degradation rate of 74.4 % in the 100-day soil burial experiment, and the soybean seeds grown in the degraded soil grew well, showing excellent eco-friendliness. These results show that RCAF-CC can be an alternative source of traditional agricultural films, solving the problems of non-biodegradable and high internal temperatures of the films under direct sunlight. [ABSTRACT FROM AUTHOR]

[Display omitted] • Steam gasification of a genetically modified (GMO) rice straw is investigated. • GMO rice straw exhibits superior gasification performance compared to regular one. • Co-gasification of GMO rice straw with Giant Miscanthus is investigated. • Seaweed biochar addition can greatly enhance co-gasification with reduced tar. • Promoting synergistic effect by low-cost catalyst for co-gasification is clarified. Future sustainability visions include clean, renewable energy from hydrogen, which can be produced, among other ways, by biomass steam gasification. This study explores strategies addressing the limitations in steam co-gasification of herbaceous biomass, using Monster-TUAT1 rice straw, a genetically modified rice plant with a taller and bigger stalk developed by Tokyo University of Agriculture and Technology (TUAT), and Giant Miscanthus, a promising energy crop, as the feedstock. Firstly, compared with the typical rice straw, the Monster TUAT1 demonstrated superior steam gasification performance with a 1.75 times higher hydrogen gas yield and 27.0 % less tar generation. With a focus on overcoming the challenges posed by high silica content in the Monster TUAT1, co-gasification of it with an energy crop of Giant Miscanthus was performed. However, even under the optimum operation condition (750 °C, steam flowrate: 0.15 g/min), the hydrogen gas yield was only 29.3 mmol/g-C with a tar yield of 27.6 %wt. and a carbon conversion efficiency of 45.9 %, which is deemed unsatisfactory for hydrogen production. Thus, strategies for enhancement were proposed, including the incorporation seaweed biochar with high alkali and alkaline earth species, calcined scallop shell powder, and alkali metal salt into the gasifier. Consequently, the introduction of 10 %wt. of calcined scallop shell resulted in an increase in H 2 yield to 37.0 mmol/g-C and 24.3 % CO 2 reduction. The addition of alkali metal salt led to 43.9 % increase of H 2 product with a 15 %wt. tar yield. The most significant improvement occurred with the introduction of seaweed biochar at 50 %wt., increasing of the hydrogen gas yield to 62.0 mmol/g-C with 86 % of carbon conversion efficiency and tar reduction to 5.5 %. These findings demonstrate the viability of utilizing herbaceous biomass such as rice straw in conjunction with the strategic solutions of co-gasification to overcome constraints in improving hydrogen production. [ABSTRACT FROM AUTHOR]

This study reports a successful continuous biohydrogen production from rice straw hydrolysate in both 3-L and 20-L dynamic membrane bioreactor (DMBR). In the 3-L DMBR (DMBR I), the maximum average bio-H 2 production performance was 32.13 ± 0.71 L H 2 /L-d, 1.27 ± 0.03 mol H 2 /mol hexose-equiv consumed , and 96.39 ± 2.12 L H 2 /d, respectively. The H 2 production performance of 20-L DMBR (DMBR II) was comparable to DMBR I, which were 33.15 ± 0.42 L H 2 /L-d, 1.46 ± 0.03 mol H 2 /mol hexose-equiv consumed , and 663 ± 8 L H 2 /d, respectively. Rapid decline of hydraulic retention time (HRT) in the early stages of operation led to the metabolic flux of the mixed culture from the lactic acid pathway to the H 2 -producing pathway. Genus Clostridium was the dominant microbial population in DMBR I and DMBR II. This study provides operational criteria and insights in the scale-up design and operation of biohydrogen production from lignocellulosic biomass. • Rice straw was converted to H 2 in 3-L and 20-L dynamic membrane bioreactor. • 663 ± 8 L H 2 /d was recovered continuously from a 20-L bioreactor. • Maximum H 2 production was 33.8 L H 2 /L-d and 1.3 mol H 2 /mol hexose in 20-L bioreactor. • Rapid decrease of HRT in early-stage shifted HLa pathway to H 2 -producing pathway. • Feeding of rice straw hydrolysate shifted H 2 -producing pathway from HBu to HAc. [ABSTRACT FROM AUTHOR]

• OsPDR20 is induced by Cd and localized to the plasma membrane. • Knockdown of OsPDR20 compromised rice growth and development. • Knockdown of OsPDR20 led to accumulated Cd in rice. • Developing OsPDR20 genotype is critical for phytoremediation of Cd-polluted wetland soils. Cadmium (Cd) is a non-essential toxic heavy metal, seriously posing high environmental risks to human health. Digging genetic resources relevant to functional genes is important for understanding the metal absorption and accumulation in crops and bioremediation of Cd-polluted environments. This study investigated a functionally uncharacterized ATP binding cassette transporter G family (ABCG) gene encoding a Pleiotropic Drug Resistance 20 (PDR20) type metal transporter which is localized to the plasma membrane of rice. OsPDR20 was transcriptionally expressed in almost all tissues and organs in lifespan and was strongly induced in roots and shoots of young rice under Cd stress. Ectopic expression of OsPDR20 in a yeast mutant ycf1 sensitive to Cd conferred cellular tolerance with less Cd accumulation. Knockdown of OsPDR20 by RNA interference (RNAi) moderately attenuated root/shoot elongation and biomass, with reduced chlorophylls in rice grown under hydroponic medium with 2 and 10 µmol/L Cd, but led to more Cd accumulation. A field trial of rice grown in a realistic Cd-contaminated soil (0.40 mg/kg) showed that RNAi plants growth and development were also compromised compared to wild-type (WT), with smaller panicles and lower spikelet fertility but little effect on yield of grains. However, OsPDR20 suppression resulted in unexpectedly higher levels of Cd accumulation in rice straw including lower leaves and culm and grain. These results suggest that OsPDR20 is actively involved in Cd accumulation and homeostasis in rice crops. The increased Cd accumulation in the RNAi plants has the potential application in phytoremediation of Cd-polluted wetland soils. [Display omitted] [ABSTRACT FROM AUTHOR]

Rice straw is a promising feedstock for gasification, and using it in combined heat and power systems allows us to generate renewable electricity and heat while reducing reliance on fossil fuels and combatting climate change. As the demand for clean energy grows, machine learning will become even more crucial for managing our energy systems. A combined heat and power system was integrated based on rice straw gasification and the applications of linear and quadratic regression machine learning algorithms were evaluated using the residual analysis and the analysis of variance. The results show that quadratic models outperform linear models in all cases. Specifically, for efficiency modeling, the quadratic model scores 98.2 %, surpassing the linear model's 89.6 %. In emission modeling, the quadratic model outperforms the linear model with an R-sq score of 97 % versus 88.1 %. The results show that equivalence ratio of gasifier has the greatest impact, accounting for 65 % of the observed variation on emission linear model. In the quadratic emission model, linear factors contribute 58 % and quadratic factors contribute 42 %. Among the linear factors, pressure ratio has a significant influence with a contribution rate of 89 %. In terms of quadratic factors, pressure ratio has the highest influence, with a remarkable contribution rate of 92 %. This research emphasizes the significance of enhancing the precision of regression machine learning algorithms by conducting residual analysis and variance analysis. [Display omitted] [ABSTRACT FROM AUTHOR]

Microwave-assisted pyrolysis is one of the most efficient methods for solid waste management. This study employed microwave-assisted catalytic co-pyrolysis to convert Paraffin wax (PW) and rice straw (RS) into valuable char, gas, and oil products. KOH and graphite were used as the catalyst and susceptor, respectively. The RS and PW blend served as the feedstock (with a blend ratio of 0–10 g). The yields of co-pyrolysis at different blending ratios of RS: PW exhibited variations in char content (ranging from 9.8% to 22.6% by wt.), oil production (ranging from 34.1% to 76.9% by wt.), and gas formation (ranging from 13.2% to 47.5% by wt.). The effects of the RS: PW ratio on the average heating rate, feedstock conversion, and product yields were also investigated. Analyses were performed to assess the synergistic impacts on product yields, average heating rates, and conversion factors. Notably, co-pyrolysis synergy led to increased oil and char production. Furthermore, we conducted FTIR analysis on the oil and char produced through the catalytic co-pyrolysis of RS: PW. In conjunction with co-pyrolysis synergy, the catalyst facilitated the formation of amides, alkenes, aliphatic compounds, and aromatic compounds. [ABSTRACT FROM AUTHOR]

• Hydrochar production simulation scale-up using experimental data. • Economics analysis for scaling up and practical application. • Identification of hydrochar applications for the economic analysis. Despite the extensive use of engineered hydrochar (EHC) for contaminants adsorption in water, little is known about the scaling-up of EHC production which has kept the technology at a low readiness level (TRL). Full-scale EHC production was simulated to help bridge this knowledge gap. A systematic analysis was performed where EHC was produced from rice straw using hydrothermal carbonization (HTC) at 200 °C with iron addition. A techno-economic evaluation model was employed to simulate the production process and to estimate energy requirements, configuration, and cost scenarios for the HTC process. The minimum selling price (MSP) analysis of the engineered hydrochar was found to be almost half compared to the market price for other similar sorbents ($ 76/t vs. $136/t) suggesting that EHC production is feasible for scaling up. Finally, as a trial, the resulting material was tested for its efficacy in the adsorption of an anionic organic contaminant (e.g., Congo Red, C 32 H 22 N 6 Na 2 O 6 S 2) in water to identify its potential for water treatment. Experimental results showed that EHC adsorbed > 95% CR suggesting significant adsorption capability and feasibility for production scale-up. [ABSTRACT FROM AUTHOR]

The catalytic mechanism of rice straw, Oryza Sativa L., on the carbonation of shrimp farm sludges via the gasification process was investigated in this work. Rice straw possessed 75% of its weight is silicon dioxide (SiO 2) which can be utilized as an effective catalyst whereas the tar decomposition and gas production during the thermochemical process can be enhanced. In that manner, the influence of working temperature (oC), the ratio (%wt) on the amount of rice straw used in the shrimp farm sludges, and the moisture content (%) in the prepared samples are taken into account to determine the role of rice straw catalytic. Gasification processes were carried out in 60 min in a stainless steel reactor, with a feeding rate of 0.5 kg/h and an air-pumped flow rate of 2 L/min. All experiments were performed under different conditions of working temperatures (600, 700, 800, and 900 °C), sample composition (0, 20, 40, and 60 %wt of rice straw added), and moisture content of the feedstock (20, 40, 60, 80, and 90%). It is essential to confirm that the change in sample moisture content and the working temperature are also significant to the production of hydrogen throughout the process. As the moisture content increase from 20 to 40%, the hydrogen yield is proportionally increased by 5–10%. On the aspect of working temperature influence, the hydrogen composition increased from 11% at 600 °C to 27% at 900 °C for the RS sample, from 13% at 600 °C to 29% at 900 °C for the RS20, from 17% at 600 °C to 35% at 900 °C for the RS40 sample, and from 19% at 600 °C to 43% at 900 °C for the RS60 sample. The findings in this work confirm the rice straw catalyst's role in enhancing hydrogen production via the gasification process. Furthermore, this work provides guidance information for simple but effective processes that can not only deal with the sludge waste management issue but also create a waste-to-energy route suitable for medium and small-scale aquaculture businesses. [Display omitted] • Introducing an effective method to utilize the shrimp farm sludges. • Demonstrates the catalyst role of rice straw during gasification. • Enhancing hydrogen production from the source of sludges. • Providing a simple and effective waste-to-energy process. • Evaluating the role of moisture during the thermochemical process. [ABSTRACT FROM AUTHOR]

• Long-term rice straw removal reduced the total concentrations of Cd in soil. • Atmospheric deposition led to lower remediation efficiency of Cd by straw removal. • Long-term rice straw return obviously increased the bioavailability of Cd in soil. • Cd accumulation in late rice tissues was higher than early rice under straw return. Several studies have demonstrated that reintroducing crop straw to fields may intensify cadmium (Cd) contamination in agricultural soils. However, the specific effects of long-term straw management practices on Cd concentration and its bioavailability in soil-rice ecosystems remain unclear. In this context, to explore the influence of straw return (SR) and straw removal (NSR) on Cd accumulation in both soil and rice within a double-cropping system, we conducted a four-year field study. Our research study unveiled that NSR consistently decreased soil Cd concentration and its bioavailability by approximately 16.93%–27.30% and 8.23%–21.05% respectively across both study sites. Conversely, SR resulted in a substantial increase in soil Cd bioavailability, ranging from 38.64%–53.95%. Notably, compared to NSR, SR significantly increased total soil Cd by 5.47%–36.58% and increased Cd content in brown rice by 8.00%–100.24%. Remarkably, after four consecutive years of NSR, brown rice Cd concentration at the Changfeng site compiled with national safety standards (GB 2762–2022). Additionally, returning early rice straw significantly raised soil Cd bioavailability for the subsequent crop, more so than late rice straw did for the early rice the following year. The findings suggest that traditional double-cropping cultivation with straw removal can effectively mitigate Cd contamination risks in crops and farmland in Hunan Province. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Straw biochar addition effectively improved nitrogen fixation during composting. • Inhibiting denitrification and NH 4 +-N transformation were the main means. • Biochar addition reduced microbial numbers involved in nitrogen transformation. • The microbial conversion of NO 3 –-N and organic nitrogen were strengthened. • The effect of biochar derived from maize straw was better than that of rice straw. The application of straw biochar to chicken manure composting mitigated nitrogen loss. However, the impact of biochar derived from different types of straw on nitrogen fixation in chicken manure composting is discrepant, and the specific pathways remain unclear. Therefore, this study aimed to clarify the specific pathways of maize straw biochar (M) and rice straw biochar (R) to improve nitrogen fixation during chicken manure composting. The nitrogen losses in control (no addition, CK), M, and R composting were 51.84 %, 33.47 %, and 38.24 %, respectively, suggesting that adding straw biochar effectively improved nitrogen fixation. Microbial community analysis suggested that inhibiting denitrification and NH 4 +-N transformation by microorganisms was the primary means of improving nitrogen fixation. Meanwhile, biochar addition reduced the number of bacteria participating in nitrogen transformation and strengthened the NO 3 –-N and total organic nitrogen transformation processes, among which the effect of M composting was stronger. The stronger effect was attributed to the significant role of the core microorganisms in M composting in shifting the transformation processes of the nitrogen components (P < 0.05). Therefore, the function of different straw biochar was determined by its different impacts on the microbial community, highlighting the important role of microbial community variability. [ABSTRACT FROM AUTHOR]

Biomass-based energy systems are gaining popularity as a clean and renewable source of energy, and have the potential to be a major contributor to the transition towards a sustainable energy future. In this regard, a novel multi-generation energy system is developed based on the biomass combustion. Wood chip and rice straw biomass is combusted with air agent and triggers an integrated system comprises a gas turbine cycle, a proton exchange membrane electrolyzer, a supercritical carbon dioxide Brayton cycle, and a humidification-dehumidification desalination system. The performances of wood chip and rice straw in triggering the system are compared from environmental and energy indicators viewpoints. The system fueled by wood chip emits lower carbon dioxide emission compared to the system fueled by rice straw (8.294 g/kWh compared to 10.41 g/kWh). However, the rice straw-fueled system results in higher efficiency than the wood chip-fueled system (69.9% compared to 69.1%). The system fueled by wood chip produces 2.68 kg/h of hydrogen while this value if 1.96 kg/h for the system fueled by rice straw. The research validated the possibility of utilizing energy systems that incorporate wood chip and rice straw biomass across various generations and showed the superiority of the wood chip in most cases. [ABSTRACT FROM AUTHOR]

The fabrication of ZSM-5 for the catalytic pyrolysis of biomass into highly selective valuable aromatics remains a challenge. This study investigates the product selectivity of rice straw pyrolysis without and with P-ZSM-5, alkali (0.4 M ZSM-5) and metal (8 wt% Ni-ZSM-5) modified catalysts via Py-GC/MS. Results revealed that the addition of catalysts significantly affected product distribution, with maximum selectivity of aromatics (47%) over 8 wt% Ni-ZSM-5 followed by P-ZSM-5 (44%) and 0.4 M ZSM-5 (42%). 8 wt% Ni-ZSM-5 exhibited the additive effect for monoaromatics with a maximum yield of BTX (67.23 mg/g) due to improved acidity responsible for the promotion of acid catalyzed reactions. Furthermore, the thermo-kinetics of rice straw without and with catalysts were investigated using thermogravimetric analysis. Thermogravimetric analysis shows that the degradation rate of rice straw reduced after the addition of catalysts. From the kinetic analysis, the value of activation energy of rice straw (114.43 kJ mol−1) decreased after the addition of catalysts, which was 102.48 kJ mol−1 (P-ZSM-5), 93.11 kJ mol−1 (0.4 M ZSM-5) and 61.89 kJ mol−1 (8 wt% Ni-ZSM-5). Thermodynamic parameters (Δ H a n d Δ G) show that catalytic pyrolysis of rice straw is an endothermic and nonspontaneous process. [Display omitted] [ABSTRACT FROM AUTHOR]

Emissions from biomass combustion depend on biomass characteristics, operating parameters and concern different types of compounds such as: CO 2 , CO, SO 2 , NO X , inorganic and organic micro-pollutants, polyciclic aromatic hydrocarbons, polychlorinated byphenils, and particulate matter. The aim of this work is the development of a fixed source sampling method for total levoglucosan emission, commonly considered, along with its isomer mannosan and galactosan as an atmosphere tracers for Total Suspended Particles generated by biomass burning. The semi-volatile behavior of such compound was taken into account and its sampling occurred by depositing the main fraction on a filter and the volatile fraction sampled by impingers filled with specific solution. Subsequently, the emission factors of levoglucosan in Total Suspended Particles from burning of rice and wheat straw varying from 53.7 to 65.8 mg/kg fuel were evaluated. The proposed method uses an isokinetic probe with quartz filter for particle fraction sampling and a system of impingers for the volatile fraction. The important result obtained from the experiment showed that a percentage between 30% and 50% of levoglucosan exceeds the filter and was sampled in the impingers. This result suggests the importance to collect both fractions of levoglucosan emission in order to not neglect the volatile fraction which represents an important component and must not be omitted. [Display omitted] [ABSTRACT FROM AUTHOR]

Combustion and depletion of fossil fuels, open burning of agricultural wastes, and use of hazardous chemicals in biofuels production route are some major challenges among scientific community. In the present study these obstacles were mitigated simultaneously. Initially, rice straw biomass was delignified using a combined eco-friendly laccase-assisted sodium chlorite (LASC) pretreatment. The combined pretreatment strategy of rice straw biomass reduced 55.6% lignin and increased the total available carbohydrate by 1.43 fold. Further, enzymatic digestion of LASC pretreated rice straw using a formulated cellulase cocktail from Aspergillus flavus MDU-5 and Trichoderma citrinoviride MDU-1 liberated 526.68 mg/g sugars with high saccharification yield (84.0%). The enzymatic hydrolysates thus obtained were found to contain 7.43–16.78 g/L sugars. The cellulolytic hydrolysates when fermented with Saccharomyces cerevisiae NCIM-3640 produced 3.02–7.28 g/L bioethanol, with high yield (72.96–85.31% of the theoretical value). Parallelly, lignin extracted from waste pretreatment stream showed biopesticidal activity against the larvae of H. armigera ; whereas, the evaluation of residual material (after hydrolysis and fermentation) exhibited biofertilizer properties. These findings suggests that the environmentally benign LASC pretreatment, cellulase cocktail, and utilization of waste stream for the production of biopesticide and biofertilizer may provide a promising strategy in the development of holistic lignocellulosic biorefinery process. [Display omitted] [ABSTRACT FROM AUTHOR]

Elemental-sulfur-driven autotrophic denitrification (ESDAD) process is widely used in sewage treatment, while its low denitrification capacity has become the bottleneck of this technology. The biomass-sulfur-based mixotrophic denitrification (BSMD) process is a promising denitrification pathway to improve nitrate removal of sewage. Based on previous research, a comparative analysis of the ESDAD and BSMD processes was adopted in this study. Then, three lab-scale reactors were constructed with various BSMD filters to investigate the characteristics of the BSMD process, and the optimal BSMD filter (F 3) with the nitrate removal rate (NRR) of 556 ± 13.6 mg NO 3 –-N·L−1·d−1 was 3:1:1 by weight ratio of sulfur powder to rice straw powder to shell powder. Additionally, a pilot-scale reactor (volume: 1000 L) filled with filter F 3 was designed and operated to treat the effluent of a municipal secondary tank. The feasibility of the BSMD process in engineering application was demonstrated, accompanied by a desirable treatment capacity (hydraulic retention time (HRT) ≤ 1 h) under varying conditions. Moreover, autotrophs and heterotrophs co-existed along the pilot-scale reactor, and the autotrophs remained dominant at seasonal temperatures. In general, the prospect of the BSMD is attractive, and the outcomes of this study could provide guidance for the operation of the BSMD process. [Display omitted] [ABSTRACT FROM AUTHOR]

Butanol toxicity, oxygen sensitivity, and high substrate cost limit wider applications of the traditional Clostridium acetone-butanol-ethanol (ABE) fermentation. In this study, a wild-type Clostridium beijerinckii strain was partnered with an engineered Escherichia coli strain to improve the ABE fermentation through a co-culture. Butanol and butyrate produced by C. beijerinckii were converted into butyl butyrate – a product that can be in situ removed to reduce product toxicity – by expressing a CoA transferase and an alcohol acyltransferase in E. coli. When integrated with a pretreatment technology and using commercial cellulase, the co-culture produced 1280 mg/L butyl butyrate from rice straw in bioreactors, without the need of maintaining a strict anaerobic condition. As a process harnessing both the genetic tractability of E. coli and the superior acid- and alcohol-producing ability of Clostridium , this co-culture fermentation will be useful in producing valuable esters from low-cost waste streams. [Display omitted] • E. coli was engineered to express a CoA transferase and an alcohol acyltransferase. • Butyl butyrate was produced by the co-culture from lignocellulosic biomass. • Aerobic co-culture of E. coli and Clostridium was achieved. [ABSTRACT FROM AUTHOR]

Biochar/char slurry (CS) has the potential to be a biofuel in transport and energy applications. This work investigates the effects of varying the liquid suspension medium on the stability, rheology, and higher heating value (HHV) of a biochar-based-slurry biofuel. The slurry was formed with 40 %wt. of rice straw biochar (RSB) and water and ethanol-water mixtures as the suspension mediums. Three surfactants, sodium lignosulfonate (SL), sodium tripolyphosphate (STPP), and sodium dodecylbenzene-sulfonate (SDS), were used in water, whereas only SDS was used within the ethanol-water mixtures. All CSs exhibited a shear thinning behaviour. The lowest viscosities were 548.34, 321.27, and 218.86 mPa s at a shear rate of 100 s−1 for CS prepared with STPP and water, ethanol with SDS, and ethanol, respectively. The highest HHV of 27.75 MJ/kg was found for the CS prepared with ethanol. The stability of ethanol-based CS was lower than water-based CS. An energy balance based on the product yield, HHV and the energy used in pyrolysis shows that, an increase in energy potential of 22.67 MJ/kg than that required in pyrolysis (11.42 MJ/kg). Moreover, the RSB and CS containing ethanol have an energy densification ratio of 1.56 and 1.28, and an energy gain of 81.45% and 93.7%, respectively, compared to rice straw feedstock. The energy assessment revealed that this fuel technology might be a suitable alternative to the traditional pathway of liquid (bio-oil) and gas fuel production via fast pyrolysis and gasification. [Display omitted] [ABSTRACT FROM AUTHOR]

In this work, magnesium-modified rice straw biochar (MgBC) was prepared by chemical impregnation, and the effects of proportion, initial pH, contact time, temperature and initial concentration on the removal of Cd(II) and Pb(II) by MgBC were investigated. Additionally, scanning electron microscopy, Brunauer–Emmett–Teller, Fourier-transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) were used for the characterisation of MgBC. The results shown that MgBC surface contained massive Mg-particles and possessed more abundant O-containing groups. Batch adsorption experiments shown that the optimum adsorption efficiency of Cd(II) and Pb(II) by MgBC was achieved at ratio of 1:2 and initial pH of 6.0. The pseudo-second-order kinetic model and the Langmuir isothermal model could better describe the removal of Cd(II) and Pb(II) by MgBC. The maximum adsorption capacity of Cd(II) and Pb(II) by MgBC was 92.68 and 128.06 mg/g at pH 6.0, 35°C and initial concentrations of 10~100 mg/L, respectively. FTIR and XRD analysis shown that the removal mechanism of Cd(II) and Pb(II) by MgBC involved complexation, ions exchange, co-precipitation and electrostatic interaction. After 4 adsorption–desorption experiment, the removal efficiency of Cd(II) and Pb(II) by MgBC remained above 80%. This results indicated that MgBC had great potential for the treatment of wastewater containing Cd(II) and Pb(II). [ABSTRACT FROM AUTHOR]

• Fenton-like reactions increased the production of lignocellulolytic enzymes. • Fenton-like reactions promoted the degradation of lignocellulose. • Fenton-like reactions changed fungal communities composition and diversity. • Functional modular microbes and key species in different treatments were identified. • Reducing sugars, organic matter and amino acids were key microhabitat factors of functional modular microbes. This study aimed to explore the effect of Fenton-like reactions on lignocellulosic degradation performance and identify their driving factors during composting. Rice straw was pretreated by inoculating Aspergillus fumigatus Z1 and then adding Fe (II), which resulted in Fenton-like reactions. The treatment groups included CK (control), Fe (addition of Fe (II)), Z1 (inoculation of A. fumigatus Z1), and Fe + Z1 (inoculation of A. fumigatus Z1 and addition of Fe (II)). The results suggested that Fenton-like reactions can produce lignocellulolytic enzymes and degrade lignocellulose, due to the variation in microbial community composition and diversity. In addition, functional modular microbes were identified by network analysis, which can produce endoglucanase and xylanase. Regarding ligninase, bacteria were more favorable for producing manganese peroxidase, and fungi were more favorable for producing laccase. Additionally, reducing sugars, organic matter, total nitrogen and amino acids were key microhabitat factors of functional modular bacteria, while organic matter, reducing sugars, amino acids and C/N were key microhabitat factors of functional modular fungi, thereby promoting the degradation of lignocellulose. This study provides technical support for lignocellulosic degradation based on Fenton-like reactions. [ABSTRACT FROM AUTHOR]

• OsLCD mutation reduced Cd translocation and increased Cd tolerance in rice seedlings. • Cd accumulation may be reduced by mutating OsLCD in a variety of rice genotypes. • OsLCD mutation may reduce Cd accumulation alone or in combination with other mutations. • CRISPR/Cas9 mutation of OsLCD can be used to generate low-Cd rice germplasms. • Unlike OsNramp5 mutation, OsLCD mutation does not impair essential elements. The OsLCD gene, which has been implicated in cadmium (Cd) accumulation in rice, might be a useful target for CRISPR/Cas9 editing. However, the effects of OsLCD gene editing on Cd accumulation, plant growth, and yield traits remain unknown. Here, we used CRISPR/Cas9 to generate oslcd single mutants from indica and japonica rice cultivars. We also generated osnramp5 single mutants and oslcd osnramp5 double mutants in the indica background. When grown in Cd-contaminated paddy soils, all oslcd single mutants accumulated less Cd than the wild types (WTs). Consistent with this, oslcd single mutants grown in Cd-contaminated hydroponic culture accumulated significantly less Cd in the shoots as compared to WTs. This decrease in accumulation probably resulted from the reduction of Cd translocation under Cd stress. Oxidative damage also decreased, and plant growth increased in all oslcd single mutant seedlings as compared to WTs in the presence of Cd. Plant growth and most yield traits, as well essential element concentrations in rice seedling shoots, brown rice, and rice straw, were similar between oslcd single mutants and WTs. In the presence of Cd, Cd concentrations in the brown rice and shoots of oslcd osnramp5 double mutants were significantly decreased compared with WTs as well as osnramp single mutants. Our results suggested that OsLCD knockout may reduce Cd accumulation alone or in combination with other knockout mutations in a variety of rice genotypes; unlike OsNramp5 mutations, OsLCD knockout did not reduce essential element contents. Therefore, OsLCD knockout might be used to generate low-Cd rice germplasms. [ABSTRACT FROM AUTHOR]

In this study, four kinds of straws with different biochemical compositions, including soybean straw (SS), peanut straw (PS), rice straw (RS), and corn straw (CS), were subjected to catalytic hydropyrolysis (HyPy) to explore the influence of biochemical composition on the products distribution and properties of the pyrolysis oil. The HyPy reactions were performed at 400 °C for 2 h with added 10 wt% Pd/C and 4 MPa H 2. During the HyPy, hydrogen and catalyst broke the coating structure and hydrogen bond between cellulose (CL) and hemicellulose (HCL), and thus significantly weakened the biochemical composition effect on the yield and elemental composition of the bio-oil. The bio-oil yield varied between 11.75 wt% and 13.05 wt%, and the C, H, N, O, and S content fell into the following ranges of 82.06–85.15 wt%, 9.24–9.61 wt%, 1.18–1.43 wt%, 4.62–7.86 wt%, 45–130 ppm, respectively. Biochemical composition of straw, especially the mass ratio of CL to HCL (m CL / m HCL), markedly influenced the molecular composition of the bio-oil. Hydrocarbons (20.15–46.66%) and phenolic compounds (17.01–47.98%) accounted for the vast majority of the identified compounds. SS and PS with higher m CL / m HCL (1.92 and 1.80, respectively) tended to produce bio-oils with more aromatics (22.63% and 20.70%, respectively) and fewer phenolic compounds (17.01% and 22.56%, respectively). [Display omitted] • Biochemical composition markedly influenced the molecular composition of the bio-oil. • Hydrogen and catalyst weakened the biochemical composition effect on the yield of bio-oil. • Hydrocarbons and phenolic compounds occupied the vast majority of the four bio-oils. • Higher m CL / m HCL in straws led to more aromatics and fewer phenolic compounds in bio-oils. [ABSTRACT FROM AUTHOR]

The production of biochar by rice straw pyrolysis for application in petroleum bitumen is a mutually beneficial practice for sustainable waste management in agriculture and green development of highway industry. In this study, a systematic investigation was carried out, including the fast pyrolysis of rice straw, microscopic and macroscopic characterizations of biochar, performance evaluation of bitumen, and analysis of comprehensive benefits. The test and analysis results show that pyrolysis temperature is the key factor affecting the yield and residual rate of biochar. The biochar has a fibrous and porous structure with a complex surface texture, which is conducive to sufficient physiochemical interaction with bitumen. Compared with base bitumen, biochar modified bitumen has better rutting resistance, anti-aging performance, and temperature susceptibility. The biochar from separators achieves the most significant performance enhancement, with a relatively minor impact on the thermal cracking resistance of bitumen. Quantitatively, the high-temperature performance improves by 222.7%, while the low-temperature performance weakens by only 25.9%. Moreover, recycling rice straw in petroleum bitumen can also create great benefits to economy, environment, and society. [Display omitted] • Rice straw was converted into biochar by pyrolysis and then used in petroleum bitumen. • Pyrolysis temperature was key factor affecting the yield and residual rate of biochar. • Unique structure of biochar was conducive to physiochemical interaction with bitumen. • Biochar enhanced the resistance of bitumen to rutting, aging, and temperature change. • Biochar from separators improved bitumen performance grade from PG 64-22 to PG 70-22. [ABSTRACT FROM AUTHOR]

This study presents a circular economy approach utilizing hemp stems and rice straw, typically perceived as low-value agricultural waste, to develop a sustainable alternative to traditional plastic absorbent pads for food packaging. The development of an active material was achieved through the utilization of hemp cellulose and a bioactive extract isolated from rice straw. In addition to reducing plastic pollution, this material demonstrates the potential to enhance food preservation. This research provides evidence of the benefits of repurposing agricultural by-products to create valuable and environmentally-friendly products. Hemp cellulose was extracted, characterized, and processed to develop stable aerogels and cryogels through supercritical CO 2 drying and freeze-drying. The water stability and internal structure of the materials were guided via TEMPO-mediated oxidation and high-pressure homogenization. Both materials showed versatile physicochemical and mechanical properties. Nevertheless, with higher water sorption (2.20 mL/g), minimal dimensional changes, and lower shrinkage, cryogels were suitable for meat absorbent pad application. To enhance the cryogels functionality, they were impregnated with a rice straw bioactive extract in two different concentrations. The incorporation of the extract did not affect the structure of the cryogels, improved their mechanical properties and the antioxidant activity remained stable after drying (63.89–78.96 %). Finally, the performance of the developed materials was compared to commercial plastic pads and pristine meat preservation challenge test during 9 days at refrigeration conditions. The incorporation of rice straw extract improved meat color preservation. While moderate extract concentrations (75 mg/g) showed a protective effect against lipid oxidation, higher levels (187.5 mg/g) induced pro-oxidant reactions. This research highlights the potential of hemp cellulose-based cryogels as sustainable and functional packaging materials for meat products. [Display omitted] [ABSTRACT FROM AUTHOR]

As a low-cost byproduct of rice cultivation, rice straw (RS) is produced in large quantities, yet its efficient utilization presents a significant challenge. Herein, based on its hollow tubular shape and porous cell structure, we developed a foam composite with excellent mechanical strength. RS in its original form were first built into a three-dimensional (3D) orthogonal grid and then coupled with the incorporation of phenolic foam (PF). This approach differs significantly from the traditional method of breaking rice straw (RS) into particles or fibers to be used as fillers or reinforcement. Scanning electron microscopy established the presence of ultramicroscopic particle projections on the outer surface of RS, which is beneficial for enhancing their bonding performance by interlocking. The mechanical organization of RS, consisting of sclerenchyma cells and vascular bundles, effectively resisted deformation and enhanced the flexural and compressive strength of the RS/PF foam composite. When the RS content reached 47 %, the flexural strength and compressive strength of the result composite achieved 1.28 MPa and 458 kPa, respectively. Meanwhile, its thermal conductivity was as low as 0.0243 Wm−1K−1. Orthogonal structure of RS endowed the composite with excellent transversely isotropy and greater compressive stress edgewise (458 kPa) than flatwise (256 kPa) due to the higher axial modulus of RS. Importantly, RS/PF foam composite demonstrated excellent flame-retardant performance comparable to pure PF, because the RS orthogonal grid architecture was well infilled with PF foam. This research offers new insights into utilizing natural biological forms and designing structural reinforcement. It also provides a simple and efficient approach for utilizing RS in constructing lightweight composite. [Display omitted] ● Innovative use of natural rice straw's hollow structure as a reinforcement framework for phenolic foam. ● Utilization of long fiber processing to reduce the energy consumption of fiber filler processing. ● A simple and feasible 3D orthogonal reinforcement structure significantly improves the mechanical properties of the foam composite. [ABSTRACT FROM AUTHOR]

This study proposed an innovative process of biomass torrefied liquids washing, torrefaction, and chemical looping gasification (BW/T-CLG). The fixed-bed reactor and Py-GC/MS were used to assess the effects of combined pretreatments on CLG performance of rice straw (RS). The pretreatment results indicate that torrefaction liquids washing effectively removed ash component in the RS, and combined measures clearly enhanced the calorific values and energy density of RS. The jointly pretreated RS exhibits good cyclic stability in multiple chemical looping gasification (CLG) cycles. When the reaction temperature boosted from 700 to 900 °C, a 34 % improvement in carbon conversion efficiency (η C) and 32.9 % rise in cold gas efficiency (η G) were achieved. As the OCs proportion increased, the η C increased from 62 % to 72 %, whereas the CO selectivity (Sel CO) and the syngas content (C syngas) generally reduced, and its optimal value was determined to be 30 %. The Py-GC/MS result showed that both washing and torrefaction decreased the levels of acidic compounds while boosting the production of high-value products. • Torrefied liquids washing, torrefaction and chemical looping gasification were combined. • Torrefied liquid washing removed most of K in straw and enhanced BCLG performances. • Torrefaction enhanced fuel properties of straw, increased energy density greatly. • Combined pretreatments improved the selectivity and quality of products from BCLG. • Combined pretreatments have declined acidic substances in bio-oil and improved quality. [ABSTRACT FROM AUTHOR]

The rise in winter and spring nighttime temperatures is a hallmark of global climate change, and warming has been proven to stimulate N 2 O emissions from wheat fields. However, it remains elusive whether this increasing effect is influenced by straw return, a practice considered globally as a future climate-smart agricultural strategy. A 3-year field experiment (2020−2023) was conducted with two straw treatments (S0: straw removal; S1: straw return) and two warming treatments (W0: no-warming; W1: night-warming) to quantify the effects of straw return and night-warming on N 2 O emissions from wheat fields in a rice-wheat rotation system. Straw return (S1) boosted post-jointing N 2 O production, whereas night-warming (W1) stimulated N 2 O emissions before the booting stage. Notably, the interaction between straw return and night-warming significantly affected seasonal cumulative N 2 O emissions, with W1 causing an 11.1 % increase under S0 and a more substantial 18.1 % increase observed under S1. Moreover, both S1 and W1 increased N 2 O warming potential, yield-scaled, and biomass-scaled N 2 O emissions. Compared to S0W0, soil dissolved organic C and inorganic N content increased in S1W1, while pH declined. Both S1 and W1 enhanced soil nitrification enzyme activity, nitrate reductase activity, and nitrite reductase activity in comparison to their respective controls. Additionally, S1W1 increased N 2 O production and inhibited N 2 O reduction by upregulating AOB- amoA and nirS gene abundances and downregulating nosZ gene expression, as evidenced by the elevated (nirS + nirK)/ nosZ ratio. Random forest analysis identified that denitrification enzyme activity was the most important factor influencing N 2 O emissions. Our findings suggest that rice straw return may amplify the increasing effect of night-warming on N 2 O emissions from wheat fields. From an environmental protection perspective, straw return under the context of future warming will lead to an increased risk of N 2 O emissions, which may further exacerbate climate warming. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-HTC significantly improved the hydrochar quality as a solid fuel. • Co-HTC increased the fixed carbon but decreased the ash contents in the hydrochar. • Both HHV and fuel ratio increased as the proportions of rice straw increased. • The hydrochar combustibility index increased by 30% to 419% with co-HTC. • The synergistic effect of co-HTC is more significant at 180 °C and 220 °C. This study assessed the effects of mass mixing ratio and hydrothermal temperature on the co-hydrothermal carbonization (co-HTC) of sewage sludge and rice straw regarding the yield, chemical composition, fuel properties, surface functional groups, and combustion behavior of the hydrochar. The co-HTC increased the hydrochar yield at 180 °C but decreased it at 220 and 260 °C. The co-HTC increased the hydrochar organic matter contents, higher heating values, fuel ratios, and combustion behavior (combustibility index) by 16 % to 63 %, 15 % to 85 %, 51 % to 321 %, and 30 % to 419 %, respectively. The co-HTC also enhanced the formation of oxygen-containing functional groups on the hydrochar surface. The synergistic and anti-synergistic effects of the co-HTC were more positive at 180 and 220 °C but more negative at 260 °C. The co-HTC of municipal sludge and rice straw is promising in converting waste materials into high-quality hydrochar as a clean solid fuel. [ABSTRACT FROM AUTHOR]

Lignin is one of the most abundant and underused biopolymers in nature with limited antimicrobial activities. Herein, this work aimed to enhance the antimicrobial activity of lignin extracted from waste rice straw by ultrasonic-alkali integrated extraction (USP-AT) and modify the alkali lignin through Mannich reaction to improve its antimicrobial properties. The effects of ultrasonic pretreatment (USP) time on the chemical structure, morphology, antioxidant, and antibacterial activities of lignin were studied. The results demonstrated that the total phenolic content of USP-AT lignin was higher than that of lignin extracted by alkali treatment. Moreover, the antioxidant activity of USP-AT lignin was increased by 49.69 %–69.42 %. The antibacterial activity of USP-AT lignin against Escherichia coli and Staphylococcus aureus increased by more than 40 %. However, the antibacterial capacity of USP-AT lignin is far from meeting the requirements of antibacterial food packaging. The alkali lignin was modified by Mannich reaction in order to improve its antimicrobial properties against common spoilage microorganisms or pathogenic bacteria in food and packaging. The modified USP-AT lignin exhibit remarkable antimicrobial capacities to representative bacteria, molds, and yeasts. The antifungal capacity of modified USP-AT lignin against A. niger and P. citrinum were improved by more than 40 %. [ABSTRACT FROM AUTHOR]

Rice straw, an abundant agricultural leftover, has emerged as a viable resource for generating renewable biomaterials. Its rich composition of cellulose, hemicellulose and lignin allows development in numerous applications, from medication delivery systems to biodegradable packaging, tackling environmental and industrial concerns. The study aims to create an effective and sustainable technique for extracting and exploiting numerous components from rice straws and investigating their potential uses in biomaterials. The paper effectively shows an enhanced approach for ingredient extraction from rice straw, exhibiting higher efficiency in both process time and resource utilization. The resultant ingredients indicate remarkable promise for numerous biological applications, underlining the relevance of rice straw as a sustainable resource for advanced biomaterials. A streamlined process for obtaining high-purity ingredients from rice straw, highlighting its transformational potential in sustainable biomaterials and complex biomedical applications. [Display omitted] [ABSTRACT FROM AUTHOR]

Incorporating supplementary cementitious materials (SCM) such as rice straw ash (RSA) as cement replacement in concrete is a key path toward mitigating the contributions of cement to global climate change. A cost-benefit study and an environmental life cycle assessment (LCA) were performed to compute the impacts of water soaking, drying, and reverse osmosis (RO) of the leachate to factor in the use of rice straw as feedstock at biomass energy plants, RSA for concrete, and the RO-treated leachate as fertilizer and water for farms. The cost-benefit analysis showed that the sale of electrical energy from biomass, RSA, and fertilizer required further optimization of the processes to become profitable for the involved parties. The LCA showed a global warming avoidance equivalent to net -15kgCO 2-eq per tonne of rice straw that could be achieved by substituting fossil fuel energy resources and cement avoidance in concrete. [Display omitted] [ABSTRACT FROM AUTHOR]

The steam gasification of rice straw torrefied at 200–300 °C and its co-gasification with coal were examined in this study. The effect of torrefaction temperature on thermal behavior, reactivity, product characteristic, and synergy were investigated. The results showed that torrefaction temperature influenced the pyrolysis and char gasification stages by shifting them to higher temperature ranges. As torrefaction temperature increased, the H 2 content increased while the CO and CH 4 contents decreased, with H 2 /CO molar ratio increasing from 1.8 to 2.4. The total gas yield also increased from 0.95 to 1.30 Nm3/kg, especially with a large increase up to 27.4 %. As for the co-gasification, stages of biomass pyrolysis and coal pyrolysis overlapped at torrefaction temperature of 300 °C. The pyrolysis reactivity decreased while the char gasification reactivity increased with the torrefaction temperature increasing. The H 2 /CO molar ratio decreased slightly from 3.55 to 3.40, while the total gas yield increased from 1.87 to 1.96 Nm3/kg as well as the cold gas efficiency from 75 % to 77 %. The strongest synergistic effect on the reactivity occurred at torrefaction temperature of 250 °C. The increased torrefaction temperature enhanced the synergistic effect on the total gas yield but weakened it on the H 2 yield. [Display omitted] • Effect of torrefaction on steam co-gasification of torrefied RS and coal was studied. • The pyrolysis curves of biomass and coal overlapped at temperature of 250 °C. • Pyrolysis reactivity decreased and gasification increased with increased temperature. • 250 °C torrefied biomass presented the strongest synergy with coal in the whole process. • Synergy in pyrolysis stage was stronger than that in char gasification stage. [ABSTRACT FROM AUTHOR]

Marine fouling caused major economic losses and has been a global challenge on environment protection. Currently, photocatalytic played an important role in dealing with sea pollution, enhancing the ability of resisting the bacteria and algae effectively. Rice straw biogas residue biochar with the natural in-situ nitrogen functional group has been widely utilized in the field of photocatalytic. The nitrogen functional group could effectively improve the photogenerated carrier transport rate. In addition, Cu 2 O as a typical photocatalyst could boost the photocatalytic ability, improving the performance of photocatalytic antifouling. In this work, the rice straw biogas residue biochar and Cu 2 O composited material (BRC) was synthesized by hydrothermal treatment and utilized in the field of photocatalytic and pollution removal. The natural nitrogen-containing lignocellulosic biochar was carbonized from rice straw biogas residue after anaerobic digestion and hydrothermal treatments. The BRC could impede the electron-hole complexation and continuously and efficiently generate reactive oxygen species (ROS), possessing an efficient photo-utilization rate. The BRC could exhibit excellent photocatalytic antifouling performance, with an antimicrobial rate of more than 95 %, and Chlorella adhesion density reduced by 94 %. In addition, BRC not only realized the resourceful utilization of agricultural waste, but also had a good prospect for the practical application of marine antifouling. [Display omitted] • Biochar natural nitrogen groups was doped into Cu 2 O to reduce the band gap width. • The inhibitory mechanisms include Cu2+ toxicity and continuous ROS generation. • The rough surface of BRC improved the hydrophobicity and prevent attachment. [ABSTRACT FROM AUTHOR]

Polymeric diphenylmethane diisocyanate (pMDI) is an indispensable material used to produce straw particleboard. However, prolonged exposure to high concentrations of pMDI significantly increases the health risks to relevant professionals. Herein, we report a strategy for reducing safety hazards by partially replacing the pMDI with a bio-based adhesive. An adhesive with multiple cross-linked networks were synthesized using citric acid (CA), sucrose (SU), and pMDI first, and then applied to the preparation of straw particleboard. The amide and esterification reactions between the adhesives and rice straw particles form covalent bonds, enhancing boards adhesion and water resistance. Furthermore, acidic conditions provided by citric acid facilitate to convert SU into 5-hydroxymethyl furfural (5-HMF), which plays a positive role in straw adhesion. Adhesives made with 2.4 % pMDI, 8 %, and 4.8 % SU were used to bond particleboard, achieving internal bond strength, bending strength and elastic modulus of 0.57 MPa, 25.87 MPa, and 3.77 GPa, respectively, whose mechanical properties are comparable to the particleboard prepared with 4 % pMDI. The board showed superb mechanical performances, mould resistance, as well as water resistance. The CA/SU-modified pMDI adhesive system shows significant potential and promising application value in straw particleboard. [Display omitted] • Cross-linking 5-HMF with citric acid and pMDI will improve the adhesive strength. • The high osmotic pressure produced by sucrose inhibits the growth of fungi. • Reduce the amount of PMDI by 40 % while improving the performance of the board. [ABSTRACT FROM AUTHOR]

This study presents a novel biotechnological approach for creating water vapor-resistant cryogels with improved integrity. Rice straw cellulose was transformed into nanofibrils through TEMPO-mediated oxidation and high-pressure homogenization. The resulting cryogels remained firm even when immersed in aqueous media, whose pores were used by live cell to deposit polyhydroxyalkanoate (PHA) particles inside them. This novel method allowed the compatibilization of PHA within the cellulosic fibers. As a consequence, the water sorption capacity was decreased by up to 6 times having just 4 % of PHA compared to untreated cryogels, preserving the cryogel density and elasticity. Additionally, this technique can be adapted to various bacterial strains and PHA types, allowing for further optimization. It was demonstrated that the amount and type of PHA (medium chain length and small chain length-PHA) used affects the properties for the cryogels, especially the water vapor sorption behavior and the compressive strength. Compared to traditional coating methods, this cell-mediated approach not only allows to distribute PHA on the surface of the cryogel, but also ensures polymer penetration throughout the cryogel due to bacterial self-movement. This study opens doors for creating cryogels with tunable water vapor sorption and other additional functionalities through the use of specialized PHA variants. [Display omitted] [ABSTRACT FROM AUTHOR]

Although extensin is a typical wall protein functional for plant cell wall construction and biomass production, its regulation on lignocellulose conversion into biofuels and bioproducts remains elusive. By collecting two extensin-overproduced rice straws (OsEXTLs), this study determined their cellulose levels significantly increased by 10 % along with soluble sugars and starch accumulation raised by 1–3.6 folds. After mild 0.5 % NaOH pretreatment, the OsEXTLs straws showed relatively enhanced biochemical conversion into total bioethanol production. Further under classic thermal-chemical conversion with the OsEXTLs enzyme-undigested lignocelluloses, this study generated the non-collapse biochar with more active chemical groups and the highest porosity, which caused mostly raised adsorption capacities with methylene blue (1162 mg/g) and Congo red (2714 mg/g) as a comparison with the previously-reported ones. Therefore, we proposed a mechanism model to illuminate how the extensin-enriched lignocellulose favors for higher-yield bioethanol conversion and better-performance biochar assembly, providing a novel strategy for desirable lignocellulose modification and effective biomass process. • Extensin-overproduced rice straw converts sugars and starch to high bioethanol yields. • Non-collapse biochar from enzyme-undigested lignocellulose maximizes dye adsorption. • Desirable biochar has high porosity and active chemical groups for enhanced adsorption. [ABSTRACT FROM AUTHOR]

Cadmium (Cd) contamination necessitates effective remediation approaches. This study valorizes rice straw biochar by enhancing its Cd sorption capacity through sulfur functionalization. Biochar was functionalized with sulfur compounds (H 2 SO 4 , Na 2 S, and Na 2 S 2 O 3) to introduce Lewis soft base characteristics for improved affinity towards Cd(II), a Lewis soft acid. Characterization confirmed successful grafting of various sulfur groups, increasing the sulfur content from 0.33% to 13.27% and boosting oxygen-containing functional groups. The sulfur-functionalized biochar demonstrated significantly enhanced Cd(II) sorption compared to pristine biochar, with a maximum capacity of 34.40 mg g−1 at pH 5.0 – a 17.3-fold increase – and reduced equilibrium time from 8 h to 5–10 min. Density functional theory calculations suggested that sulfur doping facilitated Cd-S bond formation and modulated the electronic properties of the biochar-Cd systems, contributing to the superior sorption performance. Sulfur functionalization offers a cost-effective, eco-friendly method for enhanced Cd(II) removal, validated by experiments and theory. [Display omitted] • Modifying biochar with S-compounds boosted S content from 0.33 to 13.27%. • S-functionalized rice straw biochar enhanced Cd sorption capacity. • Cd sorption achieved 34.40 mg g−1 at pH 5.0, a 17.3-fold increase vs pristine. • S-modification reduced equilibrium time from 8 h to 5–10 min. • S-doping altered biochar's electronic properties and promoted Cd-S bonding. [ABSTRACT FROM AUTHOR]

[Display omitted] • Four integrated routes for rice straw-to-methanol were designed and simulated. • Energy and exergy analyses were conducted for each route. • Carbon emissions from methane and nitrous oxide in rice fields were calculated. • Lifecycle carbon emission intensity of methanol was reduced by over 70 %. • External renewable electricity and self-generated electricity are recommended. The advancement of maritime decarbonization has accelerated the adoption of alternative marine fuels, particularly methanol. However, its widespread adoption encounters three primary obstacles: pricing, availability, and carbon accounting. Given the current state of technological and industrial developments, designing technical routes that comply with carbon emission restrictions is a primary concern for all project stakeholders. Therefore, based on a 100,000 tons/year biomass-to-methanol (BTM) plant located in the eastern coast of China, four integrated routes were designed and simulated to obtain steam, electricity and water balances. Energy and exergy analysis were then performed. Finally, a carbon emission assessment (calculated as equivalent carbon dioxide 'CO 2 eq') was conducted with 30 scenarios. Results indicated that the carbon emissions during rice straw production stage, including carbon emissions from methane and nitrous oxide emissions from rice fields, were 0.2020 and 0.5563 kg CO 2 eq/kg straw-dry using value and energy allocations, respectively. Excluding rice cultivation and harvesting, compared to the 2021 baseline level of 94 gCO 2 eq/MJ set by the European Union's Renewable Energy Directive III (EU RED III), the carbon emission intensity of methanol decreased by 75.4 %, 76.2 %, 71.5 % and 74.5 %, respectively for route 1 to 4, satisfying the EU-mandated carbon emission limit. Sensitivity analysis showed that reducing rice straw consumption and energy consumption of rice straw pulverizing, drying, and shaping could effectively reduce carbon emissions. Overall, given the carbon emission limit, for a BTM plants in plan or under-construction, this study suggests to provide external renewable electricity, or to configure self-generation utilizing by-product fuel gas and syngas. [ABSTRACT FROM AUTHOR]

[Display omitted] • Straw species significantly impact yellow mealworm (YMW) feeding efficiency. • Straw with low hardness and crystallinity show high chewability and larvae ingestion. • YMW feeding rate positively correlated with hemicellulose and crude protein content. • Physicochemical properties of straw structure impact intestinal microorganisms. Elucidating the influence of straw structure and component on the feeding efficacy of yellow mealworm is pivotal for improving insect protein production from straw. This research utilized four distinct types of straws—water hyacinth straw (WHS), corn straw (CS), rape straw (RAS), and rice straw (RIS)—as the sole substrate for larvae. Results indicated that the straw utilization rate and fresh larval weight gain rate followed the order of WHS > CS > RAS > RIS. Analysis of straw structural characteristics demonstrated that decreasing straw hardness and cellulose crystallinity, while enhancing straw chewability, facilitated the ingestion of larvae. Feeding efficiency of yellow mealworm was positively correlated with the hemicellulose and crude protein content, and inversely correlated with lignin content in the straw. Additionally, the structural characteristics and components of straw significantly influenced the composition of the gut microbiota. These results offer valuable insights for optimizing yellow mealworm feeding on straw. [ABSTRACT FROM AUTHOR]

[Display omitted] • CO 2 nanobubble water (NW) and O 2 NW increased the methane yields by 6.9% and 18.3%. • Using NW increased the electron transport system and coenzyme F 420 activities. • The key enzymes in the acidification stage were promoted with the addition of NW. • CO 2 NW enhanced genes expression of HM, while O 2 NW stimulated both AM and HM. • O 2 NW upregulated energy metabolism expression, resulting in more ATP production. Nanobubble water (NW) has been reported to enhance anaerobic digestion (AD), but its influence on the metabolic pathways of microorganisms remains unclear. In this study, the specific methane yields of rice straw in the CO 2 NW and O 2 NW treatments increased by 6.9% and 18.3%, respectively. The electron transport system (ETS) and coenzyme F 420 activities were enhanced by the addition of NW. Metagenomic analysis showed that the abundances of most enzymes in the acidification were significantly increased by both CO 2 NW and O 2 NW. Regarding methanogenesis, CO 2 NW promoted the expression of genes encoding enzymes of hydrogenotrophic methanogenesis, while O 2 NW stimulated both the acetoclastic and hydrogenotrophic methanogenesis. With the addition of O 2 NW, the expressions of modules related to the tricarboxylic acid (TCA) cycle and oxidative phosphorylation were enhanced, resulting in increased ATP production. This study provided fundamental evidence of the metabolic pathways of microorganisms mediated by NW at each stage of AD. [ABSTRACT FROM AUTHOR]

[Display omitted] • Nano-biochar improves compost maturity and reduces phytotoxicity. • Nano-CSB increases total N and P retention by 63.64% and 10.25%, respectively. • Nano-biochar enhances bacterial richness and diversity in mature compost. • Nano-BCs selectively enrich beneficial microbial species during composting. • Nano-biochar amended composts promote better plant growth in spinach seedlings. Conventional composting faces challenges of nitrogen loss, product instability, and limited humic substance formation. This study investigated the effects of nanoscale biochars (nano-BCs) derived from rice straw (nano-RSB) and corn stover (nano-CSB) on manure composting. A randomized design with five treatments was used: control, regular biochars (RSB and CSB), and nano-BCs. Nano-BCs, especially nano-CSB, significantly improved compost maturity and reduced phytotoxicity, achieving a 146.20 % germination index. They increased total nitrogen (55.09–63.64 %) and phosphorus (10.25–12.33 %) retention, reduced NH 4 +-N loss, and promoted nitrification. Nano-CSB showed the highest final NO 3 −-N content (8.63 g/kg). Bacterial richness and diversity increased by 25–30 % in nano-BC treatments, with selective enrichment of beneficial species. The unique properties of nano-BCs, including high surface area and microporous structure, improved nutrient retention and compost quality. Nano-BCs offers a promising solution for sustainable waste management and high-quality compost production in agriculture, significantly enhancing nutrient retention and microbial community regulation during composting process. [ABSTRACT FROM AUTHOR]

• Phosphorus in rice straw mainly exists in OP and NAIP, and K as WSK. • By high temperature pyrolysis, more HCl-P was converted from OP and NaOH-P. • The volatilization was mainly at 200–500 °C for P and 500–900 °C for K. • The most suitable for use as P and K fertilizer was the 600 °C biochar. Biochar is an excellent soil amendment, but its fertilizer effect on the soil is often overlooked. In this study, a series of experiments were conducted to investigate the form changes of P (phosphorus) and K (potassium) in rice straw biochar at different pyrolysis temperatures and explore its fertilizer effect characteristics. The results showed that in the rice straw, P was mainly in the form of OP (organophosphorus) and NaOH-P (NaOH extractable phosphorus), and K as WSK (water-soluble potassium). For biochars, the various forms of P at 100–200 °C and K at 100–300 °C were basically unchanged; OP in rice straw biochar decreased gradually from 200 °C to 800 °C; at 200–1000 °C, NaOH-P in biochar gradually decreased, with 9.1 % of P (wt%) at 1000 °C; HCl-P (HCl extractable phosphorus) with more bioavailable, which was mainly converted from NaOH-P and OP, increased gradually from 6.8 % to 50.9 % for P (wt%) at 200–1000 °C. At 100–500 °C, the change of TK (total potassium) was slight; from 500 °C to 900 °C, WSK decreased from 84.7 % to 23.2 % for K (wt%); at 700–1100 °C, the ASK (acid-soluble K) was relatively high, with K (wt%) of 10.6–11.6 %. The volatilization was mainly at 200–500 °C for P and 500–900 °C for K, which volatilization rates were 5.6–30.3 % and 6.3–58.9 %, respectively. Moreover, HCl-P increased from 0.167 mg/g for the raw straw to 4.554 mg/g for the 1000 °C biochar and TK from 3.632 mg/g for the rice straw to 20.91 mg/g for the 600 °C biochar. It can be concluded that the biochars at 400–700 °C were suitable for use as a slow-release P fertilizer and K fertilizer. This work provides a strong basis for using a rice straw biochar at different temperatures as a P and K fertilizer. Capsule: By pyrolysis, the rice straw biochar contains more HCl-P and TK, and can be used as slow-release P fertilizer and K fertilizer. [ABSTRACT FROM AUTHOR]