Waste Wheat Straw Research Articles

The Effect of the Type of Organic Residues and the Level of Lead on the Growth of Yellow Corn mays Zea L.

For the purpose of studying the behavior of lead in the two study soils in Basrah Governorate, southern Iraq, soil samples were collected from two sites in Basrah Governorate (Al-Zubair and Kutayban) with different chemical and physical soil properties, and their content was estimated. Of total lead, a pot experiment was carried out that included growing the yellow corn crop (mays Zea L.) in pots filled with three kg of air-dry soil from the two study soils, treated with organic waste (cow waste and wheat straw waste) at a level of 0.40 tons ha−1. Then lead was added to the two study soils at a level of 0, 50, and 100 mg Pb kg−1 soil. The experiment continued for 60 days, after which plant growth measurements were taken, as well as the amount of total and ready lead remaining in the soil. The results of the study showed that adding lead at a level of 50 mg Pb kg−1 soil significantly increased the total lead concentration compared to the comparison treatment, and the Zubair soil was superior to the Kutayban soil in terms of dry weight and absorbed quantity. The levels of materials added from cow manure and wheat straw to the two soils of the study had a significant effect. In the concentration of lead compared to the comparison treatment, with the difference in the effect of the two substances, the cow manure 40 tons ha−1 outperformed the rest of the treatments and gave the highest growth characteristics, as the dry weight of the plant and the amount absorbed reached 8.806 mg pot−1 and 2.281 mg pot−1, respectively.

Effect of alkali treatment on mechanical and water absorption properties of biodegradable wheat-straw/glass fiber reinforced epoxy hybrid composites: A sustainable alternative for conventional materials

Fiber-reinforced polymer composites are preferred over conventional materials because of their superior strength and modulus. Previously limited due to high manufacturing costs, synthetic fibers have been replaced by some natural fibers, such as waste wheat straw fibers. Here, epoxy-based polymer composites' mechanical and physical properties have been investigated, focusing on fiber weight ratios for both treated and untreated fiber. The research found that treated fibers display more effective mechanical qualities than untreated fibers, with a higher tensile strength of 54.4 MPa. The untreated Wheat Straw-Glass fiber reinforced composite has a less tensile strength of 26.3 MPa (10 wt% fiber). Pure resin-based composite has the most minor tensile strength at 1.52 MPa. The highest flexural strength obtained for hybrid composite is 88.76 MPa for treated fiber with epoxy resin and 49.6 MPa for untreated 30 wt % fiber. At the same time, the sole epoxy resin composite has the lowest value of 10.60 MPa. Untreated fiber (30 wt%) has the highest impact energy of 8J. Untreated wheat straw fiber absorbs more water due to its hydrophilic nature. In contrast, treated fiber exhibits better bonding and minimal water content, and the sole epoxy resin composite exhibits hydrophobic properties, resulting in less water absorption. The treated fiber displays better bonding than the untreated fiber throughout the SEM analysis. Wheat Straw fiber is mainly used for biodegradable plastic formation, housing construction, building materials, etc.

Preparation of Wheat Straw Hot-Pressed Board through Coupled Dilute Acid Pretreatment and Surface Modification.

The production of wheat straw waste board materials encounters challenges, including inadequate inherent adhesiveness and the utilization of environmentally harmful adhesives. Employing a hot-pressed method for converting wheat straw into board materials represents a positive stride towards the resourceful utilization of agricultural wastes. This study primarily focuses on examining the influence of hot-pressing process conditions on the mechanical properties of wheat straw board materials pretreated with dilute acid. Additionally, it assesses the necessity of dilute acid treatment and optimizes the hot-pressing conditions to achieve optimal results at 15 MPa, 2 h, and 160 °C. Furthermore, a comprehensive process is developed for preparing wheat straw hot-pressed board materials by combining dilute acid pretreatment with surface modification treatments, such as glutaraldehyde, citric acid, and rosin. Finally, a thorough characterization of the mechanical properties of the prepared board materials is conducted. The results indicate a substantial improvement in tensile strength across all modified wheat straw board materials compared to untreated ones. Notably, boards treated with glutaraldehyde exhibited the most significant enhancement, achieving a tensile strength of 463 kPa, bending strength of 833 kPa, and a water absorption rate of 14.14%. This study demonstrates that combining dilute acid pretreatment with surface modification treatments effectively enhances the performance of wheat straw board materials, offering a sustainable alternative to traditional wood-based board materials.

Effect of freeze-thaw cycles on the mechanical performance of wheat straw biomass ash modified soil

In cold regions, freeze-thaw cycles (FTCs) can alter the properties of soil used as a foundation filler, leading to failures in foundation engineering. The increase in biomass power plants has resulted in a significant amount of waste biomass ash, causing negative environmental impacts. To address these issues, waste wheat straw biomass ash (WSBA) is harnessed to enhance the properties of silty clays. This study examines how WSBA affects the mechanical properties and microstructure of silty clay after FTCs through FTCs tests, Triaxial tests, and Scanning Electron Microscopy (SEM) tests. The findings reveal that incorporating WSBA significantly enhances the mechanical properties and microstructure of the soil by filling internal pores and strengthening its structure. The mechanical properties of all soil samples exhibit significant deterioration after 1 FTC, with gradual stabilization ensuing after 6 FTCs. Notably, WSBA-modified samples show better resistance to freeze-thaw weathering compared to unmodified samples, particularly at a WSBA content of 10%. Furthermore, the study establishes empirical formulas linking mechanical parameters, freeze-thaw cycles, and WSBA content using binary quadratic equations. The investigation results could serve as a valuable reference for projects involving roadway subgrade backfill materials in regions with seasonal frozen soil.

Impact of Waste Cooking Oils Addition on Thermophilic Dry Co-Digestion of Wheat Straw and Horse Manure for Renewable Energy Production in Two Stages.

Anaerobic co-digestion of waste wheat straw and horse manure in two steps was revealed as a promising option for renewable energy production in the form of hydrogen and methane. Addition of waste cooking oils, disposal of which could cause damage to health or the environment, as a third substrate for digestion, is suggested as an approach not only to help handle the increasing volume of food waste worldwide but also to improve process performance. In the present study, waste cooking oil, in a concentration of 5%, appeared to be a positive modulator of anaerobic digestion with the production of hydrogen and did not lead to inhibition of the hydrolysis phase. The overall efficiency of the two-stage anaerobic digestion of the mixture, which contains mainly lignocellulose waste, is positively dependent on thermochemical pretreatment with the alkali reagent (Ca(OH)2), but elevated temperature (55 °C) and cooking oil addition revealed the opportunity to omit the pre-treatment step. Nevertheless, the overall energy production was lower due to the methane production step. However, the addition of waste cooking oils to the process in which lig-nocellulose is not pretreated (V3) led to an increase in the methane production and energy yield compared to V1. The anaerobic digestion of lignocellulosic waste is a complex process and comprises successive degradation pathways and syntrophic microbial associations' activities, so the division in two reactors ensured suitable conditions for the microorganisms residing in each of them. In this study, along with the production of hydrogen and methane and the separation of the hydrolysis and methanogenesis stages, utilization of agriculture- and kitchen-generated wastes was realized in the context of waste-to-energy sustainable production methods.

Beyond waste: Transforming wheat straw into oxygen and UV‐resistant cellulose films

AbstractRegenerated cellulose membrane is a biomaterial obtained by activating, dissolving, solidifying, and regenerating cellulose powder using solvents of different polarities. It has the characteristics of high oxygen resistance and high strength. However, its low water vapor barrier and single function limit its application. In order to improve the water resistance of regenerated cellulose membranes and endow them with UV resistance, lignin was extracted from waste wheat straw using formic acid method. The extracted formic acid lignin (FAL) was added to the cellulose solution to prepare a series of regenerated lignocellulosic membranes (RC‐FAL) with different lignin contents. The results indicate that lignin can not only improve the water vapor barrier, tensile strength, and water resistance of the film, but also enhance the oxygen barrier and UV absorption of the film. Compared with pure cellulose film, the contact angle of lignocellulose film can be increased by 66.2%, the UV absorption rate can reach 100%, and the oxygen transmission coefficient has no significant effect. In this paper, a new kind of biological packaging material with high oxygen resistance, strong ultraviolet absorption, and water resistance was prepared by recycling waste wheat straw, it has a broad application prospect in the industrial production of packaging materials.

Current approaches toward the removal of methylene blue dye from synthetic textile effluent using bacterial treated agricultural waste absorbent through statistical design

Massive amounts of wastewater are produced by the textile industry, and this waste needs to be appropriately managed. Agricultural waste wheat straw (WS), a biosorbent that is both economically available and environmentally acceptable, was used in this work to treat textile effluent. Microbial treated modification approaches were utilized for WS to study the dye removal from textile wastewater. Total 15 different isolates were screened for the dye degradation ability from Surat textile industrial effluent. The most significant deterioration was seen in PPSUHB3 when compared to other isolates. The amount of methylene blue dye removal was examined using the isolate PPSUHB3 due to its high efficiency. Based on 16s rDNA sequencing, it was predicted that the isolate PPSUHB3 was Bacillus licheniformis, having great capacity to degrade dye & wheat straw by producing efficient enzyme. The isolate showed the highest decolorization % of MB dye during optimization with WS absorbent which was verified using FTIR and SEM. The dye removal process parameters were statistically optimized using a central composite design (CCD). Wheat straw with particle sizes of 180–250 mm was discovered to be a possible adsorbent for the removal of colour. The maximum removal of MB (55.89%) was obtained using a statistical experimental design at pH 6.36, Temperature 44.6 °C, and Bacteria Concentration 3.04%. The created model is highly significant, according to the ANOVA, which found an R2 value of 0.9812 for it. The validation experiment revealed that the experimental and projected results were strikingly similar. The study found that using bacterial treated wheat straw as an adsorbent may remove wastewater that contains colours at a low cost.

A novel, spongy mesoporous hybrid bio-adsorbents derived from agricultural waste for highly selective thorium recovery

The expansion of engineering and development of porous materials for the bio-adsorbents synthesis from agro-waste-derived as superior efficient extractors is a significant economic and environmental breakthrough. Here, a novel spongy mesoporous hybrid silica (SMS-L) was successfully prepared from wheat straw by developed dissolution/precipitation methodology. This manuscript aims to extract/preconcentrate 232Th isotope from Egyptian cataclastic rock (ECR) using SMS and SMS-L bio-adsorbents. The proposed bio-adsorbents/extractors provide high adsorption capacity toward the 232Th isotope ions depending on the pH value of the extraction process. The optimum conditions of leaching (batch procedure), adsorption and elution (batch and permanent-bed columnar procedures) were investigated through a series of practical experiments. The physical parameters like isotherm, kinetic, and thermodynamics were studied. The SMS and SMS-L are considered promising bio-adsorbents for the adsorption/trapping of 232Th isotope from real leach solutions of ECR. These characteristic features may attribute to (i) the recycling and management of sustainable wheat straw wastes, (ii) the low-cost and eco-friendly, (iii) superior adsorption capacity of 232Th isotope, (iv) selective-trapping of 232Th isotope ions among other competitive ions such as Cr3+, Pb2+, Sr2+, Zn2+, Zr4+, Ba2+, Cu2+, Ni2+, V3+ and REEs, and (v) the structural stability of SMS and SMS-L bio-adsorbents even after 10 adsorption-desorption recycles without marked reduction in the Th(IV)-extraction efficacy. This report offers a foundation for additional advancement in clean energy applications.

Extraction of nanocellulose from wheat straw and its characterization

The present study aimed to isolate nanocellulose from the wheat straw by employing mechanical grinding after chemical treatments and characterizing them. The size of extracted nanocellulose was measured by DLS. Further, structural, morphological and optical properties of extracted nanocellulose and fibers were analyzed through FT-IR, FESEM and UV–vis spectrometer, respectively. The optical absorbance of nanocellulose and fibers were estimated from the 200 to 800 nm wavelength range. The absorbance of nanocellulose was observed 55 % lower than untreated wheat straw. The FTIR spectra were measured at wave number ranged 4000–400 cm−1, which showed changes in the structure after treatments and ensured the removal of the hemicelluloses, lignin, and other additives. The FESEM study shows that diameters of fibers were reduced after chemical treatment. This study showed that nanocellulose from waste wheat straw is a suitable reinforcing material for nanocomposites.

Efficient utilization of waste wheat straw through humic acid and ferric chloride co-assisted hydrothermal pretreatment for fermentation to produce bioethanol

The adsorbed ash and lignin contained in waste wheat straw (WWS) have been the essential factors restricting its high-value utilization in biorefinery. Hence, humic acid (HA) and FeCl3 as the additives of hydrothermal pretreatment were applied to simultaneously enhance the removal of lignin and eliminate the acid buffering of ash in WWS, respectively. The results showed that the xylan and lignin removal of WWS pretreated with 10 g/L HA and 20 mM FeCl3 could be efficiently increased from 61.4% to 72.9% and from 14.7% to 38.7%, respectively. The enzymatic hydrolysis efficiency and ethanol yield of WWS were increased this way from 44.4% to 82.7% and from 20.55% to 36.86%, respectively. According to the characterization of WWS, the synergistic interaction between HA and FeCl3 was beneficial to the cellulose accessibility and surface lignin area of WWS changed in positive directions, leading to the improvement of hydrolysis efficiency.

Selective production of monocyclic aromatic hydrocarbon from agricultural waste wheat straw for aviation fuel using Ni/ZSM-5 catalyst

Aromatic is a vital chemical raw material and product as well as an essential component for aviation fuel. Bio-based aromatics, especially the monocyclic aromatic hydrocarbon, are beneficial for the green chemical process and aviation fuel development. In this research, firstly, the effects of different kinds of metal catalysts (Pt/C, Rh/C, Ru/C, Pd/C, 65 wt% Ni/SiO2–Al2O3) on the pyrolysis behavior and aromatic hydrocarbons selectivity of four kinds of agricultural and forestry waste biomass (wheat straw, rape straw, poplar sawdust, and bamboo powder) were systematically investigated. The research results showed that the selectivity of aromatics has been largely increased in the presence of 65 wt% Ni/SiO2–Al2O3 while the carbon-based noble catalysts had few impacts on aromatics production. Furtherly, zeolite with different Si/Al ratios (5:18, 5:50, 5:85, 5:300, and 5:470) and the Ni loading amounts (5, 10, 15, 20, 25 wt%) were systematically studied. The series of Ni/ZSM-5 catalyst reduced the phenolic components in the pyrolysis products, and significantly increased the relative content of the target product aromatics, and the proportion of monocyclic aromatic hydrocarbons in the aromatic. The research results showed the ZSM-5 with the Si/Al ratio of 5:18 had the best catalytic properties for aromatic production. The loading of 10 wt% of Ni (10 wt% Ni/ZSM-5, Si/Al = 5:18) further boosted the catalytic performance for wheat straw, achieving the highest relative concentration of aromatic at 67%, of which the ratio of monocyclic aromatic hydrocarbon was 55%.

Investigation of Mechanical and Thermal Properties on Novel Wheat Straw and PAN Fibre Hybrid Green Composites

Grewia optiva wheat straw waste fibre and PAN fibre are combined in this study to create new composite materials. The novel specimens were created in the hydraulic hind moulding machine with varying percentages of mass of wheat straw fibres, PAN fibre (2–8%) in an equivalent ratio with other materials, and Kevlar fibre-based composites (2–4%). Natural fibre-reinforced clothing is getting increasingly fashionable these days; thus, this research is important. In several papers, natural fibre has been stated to have the potential to replace synthetic fibres. Natural fibre reinforcing has also proven to be quite effective as composites. It is currently used in a range of fields, including medical fields, aerospace, and the automobile industry, among others. Synthetic fibres are used. The usage of synthetic fibres such as asbestos and Kevlar has already been linked to mesothelioma, a kind of lung cancer. Many people have died as a result of Kevlar and asbestos. As a result, an effort to replace these materials is ongoing. Fabricated material’s mechanical, chemical, physical, tribological, and thermal properties were evaluated.

A new eco-friendly packaging system incorporating lignocellulose nanofibres from agri-food residues applied to fresh-cut lettuce

The present work explored the design and testing, at pilot scale, of a new food packaging prototype, based on biodegradable polymers and eco-materials obtained from agri-food residues using an environmentally friendly process for its application in vegetable products. For this purpose, several film formulations were developed with combinations of polylactic acid (PLA) and polybutylene adipate-co-terephthalate (Ecoflex®), incorporating different proportions of lignocellulose nanofibres (LCNF) obtained from an enzymatic pre-treatment of wheat straw waste. The production of the LCNF-reinforced packaging (i.e., bag) was carried out at pilot scale. The assessment of its physico-chemical properties showed an improvement of the optical properties, water vapour permeability and antioxidant capacity as compared to a fresh-cut lettuce commercial package. The improvement was more evident in formulations of 70:30 PLA:Ecoflex® with 0.5 and 1% LCNF. The application of the new formulated packaging in a product of fresh-cut lettuce was also tested by simulating real manufacturing, packaging and storage conditions at pilot scale. Results demonstrated levels of microbiological and sensory quality comparable to those observed in the commercial formulation. This work demonstrates that the development of packaging systems obtained from biodegradable materials and valorised with plant biomass from agri-food activity could be the basis for the creation of a more environmentally sustainable food packaging strategy.

Effects of nitrogen and phosphorus co-doped layering on lithium/sodium-ion storage properties of biomass-derived carbonaceous electrode materials

Biomass materials are widely sourced and sustainable, and can be used as high-quality candidates for anodes in LIBs and SIBs. In this paper, a hierarchical porous carbon doped with nitrogen atoms and phosphorus atoms with interpenetrating channel structure was successfully obtained using agricultural waste wheat straw as a precursor. Due to its larger interlayer spacing, abundant pore structure, and more exposed active sites, it exhibits excellent rate capability in both LIBs and SIBs. For LIBs, the reversible capacity of NPWSC-700 is 1059 mA h g−1 at 0.5 C. It still exhibits unprecedented long-cycle stability at high current densities (680 mA h g−1/1200 cycles/2 C and 438 mA h g−1/2000 cycles/10 C). Meanwhile, for SIBs, the capacity is 350 mA h g−1 at 0.2 C. The specific capacities of NPWSC-700 after 1000 cycles were 182 mA h g−1 and 116 mA h g−1 at 2 C and 10 C, correspondingly. In addition, through kinetic and first-principles calculations, it is demonstrated that N, P co-doping improves Li+ (Na+) diffusion rate and adsorption capacity as well as electrical conductivity, further explaining the electrochemical properties of the material. This paper investigates a sustainable route to heteroatom-doped biomass-derived carbon for energy storage systems.

Wheat straw-core hydrogel spheres with polypyrrole nanotubes for the removal of organic dyes

Straw biomass is an underutilized raw material, the use of which could make a significant contribution to sustainable development. Herein, wheat straw waste was regenerated into novel porous core-shell wheat straw-polypyrrole hydrogel spheres for the removal of dyes from wastewater. Adsorption experiments demonstrated that the hydrogel spheres had long-term structural and functional stability, and a high performance for the removal of the water-soluble model anionic dye eosin Y (EY). The maximum adsorption capacity of the hybrid spheres (520.2 mg/g) was 12 times greater than that of the wheat straw hydrogel sphere. Recycling experiments showed that it the initial adsorption capacity of 75.0% could be maintained after seven adsorption-desorption cycles, and the material could be recovered by simple filtration. The results from spectroscopic (FTIR, XPS) analysis, adsorption experiments and computational quantum mechanical modelling suggested that hydrogen bonds, π-π stacking and electrostatic forces, were involved in the removal of EY from aqueous solution. Interestingly, the hydrogel sphere exhibited enhanced adsorption at elevated temperature, and this could be attributed to the dynamic breaking of crosslinked hydrogen bonds in the hydrogel sphere and release of activated –OH. The results from this study provide a basis for the development of sustainable high-performance adsorption materials from wheat straw biomass for the removal of organic dyes from wastewater. It also provides a strategy to design adsorbents that work efficiently at elevated temperatures.

Archaeal and Bacterial Content in a Two-Stage Anaerobic System for Efficient Energy Production from Agricultural Wastes.

Anaerobic digestion (AD) is a microbially-driven process enabling energy production. Microorganisms are the core of anaerobic digesters and play an important role in the succession of hydrolysis, acidogenesis, acetogenesis, and methanogenesis processes. The diversity of participating microbial communities can provide new information on digester performance for biomass valorization and biofuel production. In this study anaerobic systems were used, operating under mesophilic conditions that realized biodegradation processes of waste wheat straw pretreated with NaOH—a renewable source for hydrogen and methane production. These processes could be managed and optimized for hydrogen and methane separately but combining them in a two-stage system can lead to higher yields and a positive energy balance. The aim of the study was to depict a process of biohydrogen production from lignocellulosic waste followed by a second one leading to the production of biomethane. Archaeal and bacterial consortia in a two-stage system operating with wheat straw were identified for the first time and the role of the most important representatives was elucidated. The mixed cultures were identified by the molecular-biological methods of metagenomics. The results showed that biohydrogen generation is most probably due to the presence of Proteiniphilum saccharofermentans, which was 28.2% to 45.4% of the microbial community in the first and the second bioreactor, respectively. Archaeal representatives belonging to Methanobacterium formicicum (0.71% of the community), Methanosarcina spelaei (0.03%), Methanothrix soehngenii (0.012%), and Methanobacterium beijingense (0.01%) were proven in the methane-generating reactor. The correlation between substrate degradation and biogas accumulation was calculated, together with the profile of fatty acids as intermediates produced during the processes. The hydrogen concentration in the biogas reached 14.43%, and the Methane concentration was 69%. Calculations of the energy yield during the two-stage process showed 1195.89 kWh·t−1 compared to a 361.62 kWh·t−1 cumulative yield of energy carrier for a one-stage process.

Electrogenerated alkaline hydrogen peroxide pretreatment of waste wheat straw to enhance enzymatic hydrolysis

Discovering low-cost and green pretreatments for efficient deconstruction of lignocellulosic biomass recalcitrance is receiving growing interests. Herein, a novel electrogenerated alkaline hydrogen peroxide (EAHP) pretreatment was first proposed to produce H2O2 and pretreat biomass concurrently in one pot. Results showed that the home-made electrode possess superior selectivity and stability. Under the optimal condition (30 mA·cm−2, 70 °C, 4 h), the novel pretreatment removed 76.3% of lignin while preserving cellulose, and the specific surface area and porosity of pretreated WS were greatly increased. The chemical and structural changes stimulated the enzymatic hydrolysis of cellulose and xylan reaching a maximum value of 83.7% and 90.8% respectively, which were significantly enhanced 4.1- and 5.3-fold compared to the original biomass. Overall, this work proposed a feasible biorefinery strategy for effective fractionation and utilization of lignocellulosic biomass.

Revealing the influence of metallic chlorides pretreatment on chemical structures of lignin and enzymatic hydrolysis of waste wheat straw

The addition of various metallic chlorides in pretreatment of lignocellulose have been widely reported to improve cellulose conversion via cellulolytic processing. However, the interaction mechanism between lignin and metallic cations is not well known. In this work, pretreatment with different concentrations of FeCl3 and AlCl3 were performed upon waste wheat straw to enhance enzymatic hydrolysis efficiency. Results showed that pretreatment with FeCl3 and AlCl3 could facilitate the enzymatic hydrolysis efficiency increasing from 50.4% to 82.9% and 76.6%, which was attributed to the enhancement of xylan removal by 33.8% (FeCl3) and 36.5% (AlCl3), respectively. Meanwhile, the surface charge, hydrophobicity, and protein adsorption capacity of lignin from waste wheat straw can be decreased by 3.3 mV, 0.6 L/g, 7.6 mg/g (FeCl3). This was due to the depolymerization of lignin in metallic chlorides pretreatment. These findings will be used to further evaluate the effect of metallic chlorides in biorefinery pretreatment.

Lignocellulose degradation, biogas production and characteristics of the microbial community in solid-state anaerobic digestion of wheat straw waste

Waste recycling is pivotal for deep space exploration or space habitation in life support systems (LSS) to enhance the material closure. This study investigated the enzymatic pretreatment and solid-state anaerobic digestion (SS-AD) of wheat straw as the major component of biomass waste in LSS for resource reclamation. Wheat straw compounds, such as cellulose, hemicellulose and lignin were significantly degraded after pretreatment with degradation at 37.47%, 46.96%, and 14.05%, respectively. SS-AD with the C/N ratio of 25 resulted in more intense lignocellulose degradation (74.20%) and more biogas yield (77.59 L/kg volatile solid) with 30 days digestion. The microbial community variation and diversity were analyzed that common fiber-degrading bacteria including Firmicutes, Bacteroidetes and Proteobacteria were dominant while the composition of the microbial genera shifted along with the digestion time. Moreover, a potential feasible strategy for biomass waste management in LSS by SS-AD was proposed.

Carbonate-oxygen pretreatment of waste wheat straw for enhancing enzymatic saccharification

Waste wheat straw (WWS), as the main solid waste from straw-handling yard in pulp mill, is often managed by combustion or sanitary landfill, representing an inefficient use and causing a great threat to the environment. Therefore, it is highly desirable to develop a facile and cost-effective method for the efficient utilization of WWS. In this work, Na2CO3-O2 pretreatment was conducted to WWS for enhancing the sugar recovery by enzymatic hydrolysis. The results indicated that Na2CO3-O2 pretreatment showed high delignification selectivity at relatively low temperature (110 °C) and total titratable alkali (TTA) charge (12 %, as Na2O), with the lignin removal and pretreatment yield of 42.0 % and 67.9 %, respectively. The low pH value of the spent liquor after Na2CO3-O2 pretreatment (∼ 8.8) prevented the severe alkaline degradation of carbohydrates. At a cellulase loading of 20 filter paper unit (FPU)/g-cellulose, the total sugar recovery based on oven dry matter of raw material was up to 66.1 %. Na2CO3-O2 pretreatment is considered to be an operable and cost-efficient biorefining process and represents a promising method for the value-added utilization of WWS.