Solid Residue Research Articles

Effect of recycled polyethylene catalyst for Mediterranean pine seed shell biomass pyrolysis on hydrogen and methane production

ABSTRACT The present study exhibits the potential of hydrogen and methane gases production from the Mediterranean pine tree seed shell biomass over recycled polyethylene wastes as catalyst. In the study, firstly, the viscosity and density of polyethylene materials and degassing point were determined. The pyrolysis was carried out at a rate of 50 °C/min at 600°C temperature. The obtained gases were analyzed with gas chromatography device. At the last step of the experiments, solid residues were observed under an optical microscope, and their microstructures were also examined. The results showed that Mediterranean pine seed shell biomass and its mixture with low-density polyethylene may produce methane and hydrogen gases. M8 catalyst, which has one of the lowest viscosity values (0.45 gr/10 min.) and highest density values (0.950 gr/cm3) produced the highest methane and hydrogen gas yields. In the pyrolysis experiments, 38.44% CH4, 19.50% CO2 and 42.06% H2 gases were obtained from Mediterranean pine seed shell biomass. Moreover, CO2 emission values of biomass were calculated and compared with DEFRA values. The study demonstrated that, since hydrogen and methane can be obtained through the pyrolysis process, Mediterranean pine tree seed shell can be classified as a new biomass source and has potential to alternative fuel to fossil-based fuels for internal combustion engines.

Enhancing volatile fatty acid production in batch test reactors by modulating microbial communities with potassium permanganate

The shift from conventional wastewater treatment plants to biorefineries is one of the most environmentally and economically sustainable pathways for extracting valuable compounds from waste. Besides chemical-physical processes, microorganisms within sewage sludge utilize organic and inorganic pollutants in the wastewater as nutrients, leading to effective water purification. However, the remaining solid sludge residue, typically destined for specific landfills or incineration, could undergo microbial fermentation to produce volatile fatty acids (VFA), metabolic precursors for biopolymers. Increasing attention has been directed towards optimizing operational parameters to enhance VFA production during sewage sludge fermentation. This study examined the impact of potassium permanganate (PP) on microbial communities during the sewage sludge's acidogenic fermentation. The results highlighted the positive effect of PP treatment, which increased COD production and VFA yield up to 1263.5 mg/L and 664.2 mg COD/L, respectively. The presence of PP significantly enhances VFA yield promoting bacteria positively linked to VFA production.

Experiment evaluation and thermodynamic analysis of pulping modification on ordered conversion of bark in supercritical water

Major obstacles of supercritical water gasification (SCWG) of lignocellulosic biomass, including ineffective pulping for energy self-sufficiency and a high conversion barrier significantly inhibited its large-scale development. In this study, the pulping effect of alkaline and salt pulping for high concentration bark slurry were compared systematically. The SCWG performances of bark (non-catalytic/catalytic) and bark slurry were evaluated. Based on energy self-sufficiency, a novel SCWG process of 50 wt% bark slurry was designated with a multistage reactor configuration and pulping process. The findings suggest that alkaline pulping had a wider applicability (reaching 50 wt%) and better rheological properties than salt pulping. Only 30 wt% bark slurry was capable for applying salt pulping because of solid residue with the excessive salt addition. Alkaline pulping resulted in an ordered conversion of 5 wt% and 10 wt% bark slurries during SCWG, with complete gasification of 5 wt% bark slurries prepared by KOH and NaOH at 650 and 680 °C, respectively. Besides, alkaline and salt pulping reduced the 26 % and 33 % carbon emissions, respectively. In the novel process, the optimal ratio of preheated water to bark slurry was 4 (water diversion to the primary and secondary gasification reactors of 1:3), which exhibits in energy and exergy efficiencies of 47.47 % and 48.63 %, respectively. This configuration reduces exergy losses in the gasification reactor and heat exchanger, aiding in the large-scale industrial output of SCWG.

A sustainable bio-circular way for biorefinery of rice straw into bioproducts based on energy-efficient pretreatment

Lignocellulosic biorefinery faces challenges associated with high energy input during pretreatment and high enzyme cost for enzymatic hydrolysis of cellulose, as well as the intricate valorization of lignin and hemicellulose. This study applied KOH-urea pretreatment to obtain maximum lignin removal of 68.93 % from rice straw at 80 °C for 60 min. The pretreatment consumed only 10.49 % of the total energy input. Five-time dilution of neutral black liquor can optimally stimulate the plant growth. Enzymatic conversion of KOH-urea-treated rice straw attained 92.02 % at 20 % solid concentration with 10 FPU cellulase/g substrate. The ethanol concentration achieved 37.02 g/L at a yield of 75.89 %. The solid residue after fermentation contained 42.40 % dietary fiber and 16.70 % protein, which is suitable as animal feed. This study developed a simple bio-circular way to concurrently produce liquid fertilizer, bioethanol, and animal feed from rice straw.

Evaluating hydrothermal liquefaction hydrochar from sewage sludge as a phosphorus resource through struvite production

Hydrothermal liquefaction (HTL) has attracted considerable attention for valorizing sewage sludge to biofuels while the solid residue, hydrochar, has received little attention for its final application. In the current work hydrochar recovered from hot separation in a pilot-scale HTL plant is evaluated for its nutrient value, in particular as a sustainable Phosphorus (P) resource. Following thorough characterization of the hydrochar, P recovery as struvite (NH4MgPO4·6H2O) is investigated to produce a fertilizer with a lower heavy metal content that could be used in current agricultural practices. P extraction using inorganic (hydrochloric and sulphuric) and organic (citric) acids is evaluated by applying 0.1–1 mol/L of acids for 1–12 h with a liquid/solid ratio of 10 mL/g. A second-order polynomial model was established by response surface methodology (RSM) to predict the P extraction with different acids. The optimum operating conditions for maximum P extraction (94 %) are suggested as 0.7 M of acid strength (H2SO4) and 6.5 h of extraction time. Addition of citric acid (CA) during the struvite precipitation from acid-leached P solution was found to improve the struvite purity from 36.6 % to 54 % with a reduction in heavy metal content. Furthermore, morphological analysis validated the formation of struvite. Upon comparison with the regulations, hydrochar was found to exceed some of the heavy metal limits but was low in polyaromatic hydrocarbons (PAHs), per- and polyfluorinated substances (PFAS) and showed low toxicity to Aliivibrio fischeri. P extraction and struvite precipitation are shown to reduce heavy metal contents below regulatory limits with P recoveries from 40 % to 67 %. Thus, as an alternative to direct land application of hydrochar, harvested struvite from hydrochar could be applied as a fertilizer with no apparent environmental risk.

Waste to wealth: Efficient wet desulfurization of electric arc furnace dust (EAFD) and recycling of desulfurization solid residue

In this study, we used calcined hazardous waste electric arc furnace dust (EAFD) as a desulfurizer for an effective wet desulfurization process. Testing for desulfurization efficacy revealed that the calcined EAFD, particularly when treated at 800 °C in an oxygen (O2) environment (termed EAFD-O2), achieved an unprecedented breakthrough sulfur capacity (BSC) of 3.71 gSO2·g−1 at 55 °C-the highest to date for EAFD applications in desulfurization efforts. Further investigation indicated that the calcination method expels certain volatile contaminants, thereby enhancing the crystallinity and lattice oxygen content of zinc oxide, the strong active phase of desulfurization in EAFD, which is principally responsible for the superior desulfurization results of EAFD-O2. Moreover, the observed reduction in the desulfurization slurry’s activity primarily stems from the depletion of the strong active phase of desulfurization (ZnO) and the resultant rise in the liquid phase’s sulfate concentration. Notably, the deactivated slurry’s solid residue predominantly consists of high-purity ZnFe2O4, a form of zinc ferrite utilized extensively for its proficiency in photocatalytic. Following straightforward processing, this substance displayed exceptional performance in photocatalytic-Fenton degradation tests on tetracycline (TC). In sum, the study not only turns hazardous EAFD into a powerful agent for removing SO2, a gaseous pollutant but also converts it into a value-added material, ZnFe2O4, thus proposing an integrated and efficient approach to solid waste management.

Alkali, thermal, or thermo-alkali pre-treatment to improve the anaerobic digestion of poly(lactic acid)?

Replacing petroleum-based plastics with biodegradable polymers is a major challenge for modern society especially for food packaging applications. To date, poly(lactic acid) represents 25 % of the total biodegradable plastics and it is estimated that, in the future, it could become the main contributor to the biodegradable plastics industry. Anaerobic digestion is an interesting way for the poly(lactic acid) end of life, even if its biodegradability is limited in mesophilic conditions. The aims of this study were to identify the best pre-treatment for maximizing the methane yield, minimizing the anaerobic digestion duration and limiting residual plastic fragments in the digestate. A systematic comparison was carried out between thermal, chemical, and thermo-chemical pre-treatment. Pre-treatment with 4 M KOH for 48 h at 35°C was effective in improving the mesophilic anaerobic digestion of the poly(lactic acid). Such pre-treatment allows obtaining 90 % of the theoretical methane potential, in 24 - 30 days. Importantly, such pre-treatment completely solubilized the poly(lactic acid), leaving no solid residues in the digestate. In addition, using KOH permits to avoid the sodication of the soil due to the digestate application as fertilizer.

Pre-Treatment of Spent Coffee Grounds Using Hydrodynamic Cavitation

Spent coffee grounds (SCGs) constitute the main solid residue of the coffee brewing process. SCGs are generated in significant amounts daily, worldwide. The effective management of this waste through biological processes is still an unresolved problem. In this study, the application of hydrodynamic cavitation (HC) as a pre-treatment method for improving the biodegradability of SCGs suspended in municipal wastewater was proposed. An orifice plate with a conical concentric hole having inlet/outlet diameter of 3/10 mm was applied as the cavitation inducer. Three inlet pressures were chosen: 3, 5 and 7 bar. The effects in time intervals of 0, 5, 10, 20, 30 and 45 min were evaluated. The application of HC led to enhanced biodegradability for each case. The results of multi-criteria decision indicated that the most efficient combination in terms of biodegradability and energy usage was obtained at the pressure of 5 bar and duration of 20 or 30 min, depending on the adopted weights. The improvements of DOC/TOC (dissolved organic carbon/total organic carbon) ratio were 57% and 71%, as compared to the untreated samples. The release of caffeine was found at pressures of 5 and 7 bar. However, at 5 bar, this effect was noticed for the longest times, 30 and 45 min, respectively.

Bioengineering solutions for expansive soil stabilization using waste materials: An experimental evaluation

Municipal solid waste incineration ash is the outcome/product of bioengineering science. The incineration or burning of municipal solid waste (MSW) reduces the volume of this biomass by 90%, and the residual ash can be used in several applications. In this study, the potential of municipal solid waste incineration (MSWI) ash and calcium carbide residue (CCR) waste for stabilization of expansive soil has been experimentally evaluated. The abnormal shrink–swell characteristics of expansive soils pose several problems for civil engineering structures when these soils are used for construction in their original form. The study presents an experimental set-up to determine the best combination of additives to achieve the most favorable technical characteristics of expansive soil for civil engineering activities. The percentage of expansive soil has been kept fixed at 60% of the total weight of the mix for varying ratios of stabilizing agents. The optimization of the stabilizing materials is based on the highest strength parameters of the mix achieved for a particular ratio of additives and soil. The two stabilizing agents are waste materials, and their disposal through landfilling has become costly due to a scarcity of space and handling mechanisms. The values of strength parameters, unconfined compressive strength (UCS), and split tensile strength (STS) of a treated mix are found to be highest for a unique combination of 60% lime stabilized expansive soil and 20% MSWI ash and an equal quantity (20%) of CCR. The cumulative effect of adding the best mix of additives to soil and curing time depicts an improvement of 526.03% in UCS and 463.41% in STS of the mix compared to one day and 28 days of curing time. There is scope for further study, such as adding some fibers to the finalized mix to reinforce the soil mix.

Novel Staged Free-Fall Reactor for the (Catalytic) Pyrolysis of Lignocellulosic Biomass and Waste Plastics.

Pyrolysis of lignocellulosic biomass and waste plastics has been intensely studied in the last few decades to obtain renewable fuels and chemicals. Various pyrolysis devices have been developed for use in a laboratory setting, operated either in batch or continuously at scales ranging from milligrams per hour to tenths of g per hour. We report here the design and operation of a novel staged free-fall (catalytic) pyrolysis unit and demonstrate that the concept works very well for the (catalytic) pyrolysis of pinewood sawdust, paper sludge, and polypropylene as representative feeds. The unit consists of a vertical tube with a pretreatment section, a pyrolysis section, a solid residue collection section, a gas-liquid separation/collection section, and a catalytic reaction section to optionally perform ex situ catalytic upgrading of the pyrolysis vapor. The sample is placed in a tube, which is transported by gravity through various sections of the unit. It allows for rapid testing with semicontinuous feeding (e.g., 50 g h-1) and the opportunity to perform reactions under an (inert) gas (e.g., N2) at atmospheric as well as elevated pressure (e.g., 50 bar). Liquid yields for noncatalytic sawdust pyrolysis at optimized conditions (475 °C and atmospheric pressure) were 63 wt % on biomass intake. A lower yield of 51 wt % (on a biomass basis) was obtained for the noncatalytic pyrolysis of paper sludge, likely due to the presence of minerals (e.g., CaCO3) in the feed. The possibility of using the unit for ex situ catalytic pyrolysis (pyrolysis at 475 °C and catalytic upgrading at 550 °C) was also successfully demonstrated using paper sludge as the feed and H-ZSM-5 as the catalyst (21 wt % catalyst on biomass). This resulted in a biphasic liquid product with 25.6 wt % of an aqueous phase and 11 wt % of an oil phase. The yield of benzene, toluene, and xylenes was 1.9 wt % (on a biomass basis). Finally, the concept was also proven for a representative polyolefin (polypropylene), both noncatalytic as well as in situ catalytic pyrolysis using H-ZSM-5 as the catalyst at 500 °C. The liquid yield of thermal, noncatalytic plastic pyrolysis was as high as 77 wt % on plastic intake, while in situ catalytic pyrolysis gave a combined 7.8 wt % yield of benzene, toluene, and xylenes on plastic intake.

Comparative Selective Conversion of Biomass-Derived Mono- and Polysaccharides into Lactic Acid with Lanthanide Lewis Acid Catalysts

Lanthanides were tested (Ce3+, Er3+, and Yb3+) as catalysts to produce lactic acid (LA) from the monosaccharides present in corn stover (glucose, xylose, and arabinose) resulting in ytterbium being the most active. A MW-heated system led to similar LA yield as a conventionally heated pressurized system. The maximum value of LA yield was 40% at 240 °C after 20 min of isothermal treatment regardless the starting monosaccharides, which allowed to propose a similar LA production route based on the products profile determined along time for the three monosaccharides. Temperature and time determined the product profile, observing furfural degradation at severity factors higher than 3.5, while values higher than 5.5 were needed to observe LA degradation. By increasing temperature, catalyst solubility decreased, increasing its presence in the solid residue after treatment. Xylan conversion to LA was similar as for xylose, but lower yield was obtained from microcrystalline cellulose. Corn stover presented more amorphous regions leading to higher hydrolysis yields of its cellulose fraction.

Physical and Mechanical Properties of Fiberboard Made of MDF Residues and Phase Change Materials

The wood-based panel industry is experiencing an excessive accumulation of solid residues from the production of medium-density fiberboard (MDF) panels and moldings. It is possible to create new MDF products with acceptable physical and mechanical properties by revaluing MDF residues. Additionally, those products’ thermal properties can be improved by incorporating phase change materials (PCMs). This study aims to develop a wood-based fiberboard made of MDF residues, capable of storing thermal energy. Two types of PCMs (liquid and microencapsulated), two PCM ratios (2% and 6%), and two types of adhesives (urea-formaldehyde and phenol-formaldehyde) were used to produce eight different types of panels. The vertical density profile, thickness swelling, water absorption, internal bond (IB), and static bending properties—modulus of elasticity (MOE) and modulus of rupture (MOR)—were determined for each panel type. The specific heat of the panels was also determined. The results show the panels’ densities were greater than 700 kg/m3. Thickness swelling in water improved by 23% compared to the reference value of the control panel PCMs after PCM incorporation. The highest IB value was 1.30 MPa, which is almost three times the minimum required by regulation standards. The incorporation of PCMs reduced the panels’ bending properties compared to the properties of the control panels. Even though the values obtained are sufficient to comply with the minimum values set out in ANSI standard A208.2 with an MOE value of 2072.4 MPa and the values obtained are sufficient to comply with the minimum standards with an MOE value of 2072.4 MPa and an MOR value of 16.4 MPa, when microencapsulated PCM is used, the specific heat of the panels is increased by more than 100% over that of the control panels. This study developed fiberboards with adequate physical and mechanical properties and capable of storing thermal energy.

Effects of vaterite and leachate solid residue prepared from magnesium slag on the performance of cement mortar

This study introduces a "leaching-carbonation" method for converting magnesium slag (MS) into two valuable byproducts: high-purity spherical vaterite calcium carbonate (VCC) derived from the carbonation of filtrate and leached solid residue (LSR) rich in amorphous silica gel. The investigation delves into the performance and microstructure of cement incorporating MS, VCC, and LSR. Results indicated that MS and LSR decreased the flowability of cement mortar, while VCC significantly enhanced it compared to the control sample. MS negatively affected compressive strength and water absorption, whereas LSR and VCC improved both aspects in comparison to MS. Although MS, LSR and VCC shortened induction period of cement paste, both LSR and VCC improved the cumulative heat release compared to the control sample. Additionally, a new hydration product, monocarbonate, was formed in the VCC sample. The presence of amorphous silica gel in LSR exhibited pozzolanic reactivity and could react with Ca(OH)2 to form C-S-H gel. Furthermore, both LSR and VCC samples exhibited a refined pore size distribution compared to the control and MS samples. In summary, the obtained results offer a promising technology for maximization of the valuable utilization of MS.

Investigating the potential of mineral precipitation in co-pyrolysis biochar: Development of a novel Cd (II) adsorption material utilizing dual solid waste

Ionic cadmium (Cd (II)) in water is a significant threat to ecosystems, the environment, and human health. Research is currently focused on developing efficient adsorption materials to combat Cd (II) pollution in water. One promising solution involves co-pyrolyzing solid residue from anaerobic digestion of food waste with oil-based drill cuttings pyrolysis residue to create a biochar with high organic matter content. This biochar has a lower heavy metal content and leaching toxicity compared to China's national standards, making it both safe and resourceful. It exhibits a high adsorption capacity for Cd (II) in water, reaching up to 47.80 ± 0.37 mg/g. Raising the pyrolysis temperature above 600 °C and increasing the amount of pyrolysis residue beyond 30 % enhances the biochar's adsorption capacity. The adsorption process is primarily driven by mineral precipitation, offering a promising approach for dual waste resource management and reducing heavy metal pollution.

Model-based process intensification of deep eutectic solvent treatment of eucalyptus slabs for lignin extraction and pulp production

This work revealed the reaction characteristics in the delignification process of eucalyptus slabs catalyzed by acidic deep eutectic solvent (benzyltriethylammonium chloride/formic acid) from the perspective of heterogeneous reactions. The limitation of internal diffusion on delignification process cannot be ignored. Afterwards, a kinetic model based on cell wall structure was proposed to describe the relationship between the delignification degree and reaction conditions, and it also hold excellent predictive ability for lignin removal, carbohydrate retention and solid residue yield. Compared with other reported kinetic models, this novel model not only took into account all operational parameters of reaction process, but also can be applied to the entire reaction process without the need for segmentation. Besides, an essential requirement based on the developed model was a 44.40 wt% formic acid concentration and a temperature of 130 °C, when the purpose of DES treatment was pulping. Generally, this work could provide guidance on process adjustments and product quality control during the DES processing.

Enhancement of light hydrocarbon production from polypropylene waste by HZSM-11-catalyzed pyrolysis

Herein, a mixture of real polypropylene (PP) waste was pyrolyzed with a HZSM-11 catalyst as a potential method to recover light hydrocarbons (C ≤ 12), the potential feedstock for value-added chemicals and fuels, from polyolefin plastic waste. Using the HZSM-11 in the PP waste mixture pyrolysis noticeably improved the yield of gas pyrolysate and oil in compensation for the yield of wax (i.e. hydrocarbons of C > 20) and solid residue particularly at a higher temperature. In addition, the selectivity of C3–C12 in the PP-waste mixture-derived pyrolysate was markedly increased by the HZSM-11. The highest yield of light hydrocarbons was ≈40 wt% (per mass of the feedstock) achieved at 700 °C with the HZSM-11 catalyst. Despite 7.9 wt% coke deposition on the HZSM-11 after its use in the pyrolysis of the PP waste mixture, the catalyst could be reusable for at least three times after regeneration. The experimental results demonstrate that HZSM-11 has the potential for being a promising catalyst to valorize polyolefin waste into value-added chemicals.

The impact of ammonifying microorganisms on the stabilization and carbon conversion of cow manure and wheat husk co-composting

Ammonifying microorganisms (Amm) play a crucial role in the global utilization of agricultural solid residue, but the mechanism of their action in the stabilization and carbon transformation of agricultural solid residue composting remains unclear. In this work, different treatments, including Control, Amm-1, Amm-2, Amm-3, and Amm-4, were established for co-composting of cow manure and wheat husk to investigate the action mechanism of Amm in composting stabilization and carbon conversion. The findings indicated that the Amm inoculation facilitated the decrease of total organic carbon, dissolved organic carbon, CO2 productions, and CH4 emissions by 35.13 ∼ 37.28 %, 15.61 ∼ 16.78 %, 1.75 % ∼ 32.38 %, and 10.30 %∼ 18.01 %, respectively. Among the treatments. The inoculation of Amm-4 immensely showed the highest improvement effect on the organic solid residue humification and carbon transformation process, with the final compost product showed high stability and favorable performance on improving crop growth. Further mechanism analysis suggested that the Amm inoculation optimized humification-related enzyme activity and fungal community structure, enhanced the humus formation, increased the humification index, and promoted the stabilization of final product. In conclusion, this investigation verified the Amm inoculation can improve compost carbon conversion and promote the green application of agricultural solid residue as resource.

Maximizing fermentable feedstocks from Camellia oleifera seed oil extraction residues: Green pretreatment and enzymatic hydrolysis for effective valorization

This study aimed to convert wastes generated during the extraction of oil from Camellia oleifera seeds, including the fruit shell (COFS) and seed cake (COSC), into fermentable feedstocks using pretreatment and enzymatic hydrolysis processes. The application of a green acid catalyst in the thermochemical pretreatment of the COFS and COSC mixture yielded the highest sugar of 28 g/L. Solid-state fermentation (SSF) was conducted on-site using various waste biomass substrates to produce enzymes for the saccharification process. This study found that COFS was the ideal substrate for generating SSF enzymes capable of breaking down lignocellulosic biomass. A novel enzymatic hydrolysis strategy was developed to minimize water consumption and enhance substrate utilization efficiency. By fine-tuning the enzymatic hydrolysis process, an additional sugar of 20.58 g/L was achieved using thermochemically pretreated solid residues and SSF enzymes. Standard techniques were used to analyze the raw materials, residual solids, and hydrolysates to assess the efficiency of each processing step. In general, the use of SSF enzymes and green pretreatment methods, reduction of water consumption in the process, and implementation of an efficient biomass utilization approach, enhance the overall efficiency and eco-friendliness of this study.

Response surface optimization of lipase production by <i>Pseudomonas sp.</i> on a low-cost shea-nut cake using solid state fermentation

Shea nut cake (SNC) is the solid residue produced after the shea butter extraction process. The SNC could provide a low-cost substrate for bacterial lipase production. Greater yield are among the benefits Solid State Fermentation (SSF). However, there have been less instances of lipase production by bacteria than fungi in SSF. The current study aimed at improving bacterial lipase production on SNC in SSF using Response Surface Methodology. Lipase-producing bacteria (LPB) were isolated from the shea butter mill effluent pond and screened for lipase production on a tributyrin agar plate. The influence of four independent parameters (temperature, pH, moisture content and biosurfactant) on lipase production was studied using Box Behnken Design (BBD) of RSM. Results showed that isolate AO (Pseudomonas sp.) displayed the highest zone of hydrolysis 2 (53 mm). A quadratic regression with R = 0.931 showed that the model is best fitting, and predicted the optimum conditions of significant (P>0.05) growth parameters, including temperature at 40°C, moisture content at 50%, and biosurfactant at 2 mL, which produced 408.25 U/g of experimental lipase. The findings indicate that the model was useful for predicting optimal growth conditions for incresing lipase production in SSF and the low-cost agro- industrial SNC could be a promising substrate for industrial applications.

An efficient and mild fractionation of corn stover via 2-phenoxyethanol and silicotungstic acid biphasic pretreatment for biomass valorization

Developing an efficient and facile pretreatment is of great importance to comprehensive utilization of lignocellulosic biomass. Herein, a biphasic system of 2-phenoxylethanol (EPH) and silicotungstic acid (STA) was employed for fractionation of corn stover. The EPH/STA biphasic system demonstrated remarkable fractionation efficiency to remove 90.23 % of xylan and 88.54 % of lignin, while retaining 85.60 % of cellulose under the mild pretreatment conditions of 130 °C for 90 min with 7/3 of EPH/STA and 40 mM of STA. The xylose of 52.93 % and lignin of 88.01 % were recovered in aqueous phase and organic phase by EPH/STA biphasic pretreatment, respectively. In the further process, 94.27 % of saccharification was achieved by enzymatic hydrolysis of cellulose-rich solid residue, and 106.17 mg/g of xylonic acid was obtained by oxidation of xylose in aqueous phase. Additionally, the recovered lignin in organic phase could be fabricated to lignin-based films with good mechanical properties. Notably, acid solvent in biphasic system had an important role in fractionation efficiency of corn stover. The STA had the best effect among the different acid solvents. This work provided a promising route to full components utilization of corn stover for biomass valorization.