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•CSPP/ZnO NPs retains the anisotropic, biological structure from corn stalk pith.•Zn2+ adsorption behaviors affecting morphology and bactericidal action of columns.•The mechanism ...clarification for improving water sterilization of ZnO NPs via CSPP.•The hybrid column exhibits excellent performance to kill pathogens by filtration.
The escalating demand for clean water and proliferation of microbial contamination in water have challenged ecosystems and human health safety. ZnO NPs are widely used as environmental restoration agents, but their efficacy in water decontamination is hindered by low biological toxicity. In order to enhance its sterilization efficiency, we propose a top-down strategy utilizing the unique maze structure of corn stalk pith (CSP) as a germ trapper for ZnO. The in-situ delignified CSP offers abundant active sites for the adsorption of Zn2+, exhibiting the typical behaviors of monolayer, physisorption, endothermicity, spontaneity, and randomness. This adsorption behavior exerts an influence on microscopic morphology of the composite column, consequently resulting in alterations to antibacterial properties. The results show that the hybrid column fabricated under the Zn2+ initial dosage of 1.00 mol/L at 30 h for 40 °C, possesses such optimal features as stacked grain-shaped ZnO NPs of 669.3 mg/g loading amount with adhesion coefficients of 0.73 ∼ 0.86 for bacterial microparticles. Consequently, the assembled bio-filter can eliminate E. coli and S. aureus as high as 99.7 % and 96.5 % respectively, attributed to CSPP labyrinth structure to enhance pathogen capture from water and facilitate ZnO-mediated inactivation. The collective findings emphasize the viability of agro-waste stalks as bio-filters for water purification.
Chitin (CT) is widely used as a hemostatic material in surgical sponges, although its efficacy needs improvement to promote the clotting process. In this study, another green biomass, corn stalk pith ...(CSP), was incorporated into CT through ball milling to fabricate CT-CSP composite hemostatic sponges to enhance erythrocyte absorption, platelet activation, and clotting factor accumulation (Ca2+). In vitro hemostatic analysis indicated that CSP incorporation greatly promoted the coagulation process, with a much lower blood clot index and higher blood clot stability. In addition, the composite sponge promoted more platelet adhesion and activation, and the composite sponge demonstrated a greater ability to bind clotting factors (Ca2+). Consistently, it achieved complete hemostasis with less blood loss and a shorter hemostatic time in a rat liver injury-model. This composite hemostatic sponge is sustainable, cost-efficient, and biocompatible, which highlight the excellent translational potential in clinical settings.
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Corn stalk pith is a waste product of papermaking from corn stalk, and is easy to digest, which makes it a promising feedstock for biofuel production. The main aim of this study is to evaluate ...utilization of corn stalk pith for hydrogen production. Corn stalk pith was hydrolyzed with commercial cellulase at 50 °C, and the hydrolysate was used as a carbon source for hydrogen production with a photosynthetic consortium. Effect of initial pH on sugar consumption, hydrogen production and byproducts accumulation was evaluated with initial reducing sugar concentrations of about 11 g/L. Single-factor experiments were conducted to determine optimal conditions. Substrate conversion efficiencies (82–94%) during photo-fermentation at initial pH of 6–9 were higher than those (40–80%) achieved in previous studies on hydrogen production from glucose using the same photosynthetic consortium. Hydrogen yield (2.6 ± 0.3 mol H2/mol sugar consumed) obtained at an initial pH of 7 was higher or comparable to those reported in literatures. During the photo-fermentation process, hydrogen was mainly produced via acetic acid production pathway in the first 24 h, and the butyric acid production pathway dominated the hydrogen production for the next 72 h. It was for the first time that corn stalk pith has been used for hydrogen production.
•Corn stalk pith was used for photo-fermentative hydrogen production.•Conditions for hydrogen production with a photosynthetic consortium were optimized.•Optimal biomass concentration and initial pH were found to be 0.18 g/L and 7, respectively.•Hydrogen yields higher or comparable to those reported in literatures were obtained.•Hydrogen production was attributed to different pathways at different periods.
•Green super water-absorbents were realized from corn stalk pith cellulose.•Tartaric acid (TA) acted as both grafting agent and cross-linker.•Esterification of TA and the dissolved cellulose increase ...absorbency by 1215.7 %.•The highly macro-porous structures of the absorbent caused fast diffusion of water.
The eco-benign water-absorbent gel was obtained by modification of tartaric acid (TA) onto parenchyma cellulose from corn stalk pith (CSP) in N, N-dimethylacetamide (DMAc)/LiCl system. The water affinity of the gel was aided with TA as both grafting agent and cross-linker via esterification. The degree of swelling was strongly influenced by TA amount, reaction temperature and duration, and the absorbency of TA-esterified product reached up to about 417 g H2O/g dry gel. The three-dimensional macro-porous structures of the bio-absorbent led to fast penetration and diffusion of water into gel. Studies of absorption behavior in deionized water showed that the initial water uptake followed the non-Fickian mechanism, the Schott second-order equation governed the swelling kinetics, and the later part of swelling was relaxation of polymer chains. FTIR and X-ray diffraction analyses confirmed successful modification of TA molecules onto cellulose chains through the formation of ester bonds and transition of crystalline forms from cellulose Ⅰ to cellulose Ⅱ. Moreover, thermogravimetric outcomes illustrated the thermal resistance of the TA-esterified gel with a loose structure was lower than SCP cellulose. This work designed a green water-absorbent that could be potentially utilized as favorable water retention material in agriculture and horticulture.
Bio-based aerogel has become an attractive sorbent for spilled oil and organic pollutants because of its light weight, high porosity and strong sorption capacity. However, the current fabrication ...process is mainly "bottom-up" technology, which is cost-expensive, time-consuming, and energy-intensive. Herein, we report a top-down, green, efficient and selective sorbent prepared from corn stalk pith (CSP) using the deep eutectic solvent (DES) treatment, followed by TEMPO/NaClO/NaClO2 oxidization and microfibrillation, and then hexamethyldisilazane coating. Such chemical treatments selectively removed lignin and hemicellulose, broke the thin cell walls of natural CSP, forming an aligned porous structure with capillary channels. The resultant aerogels had a density of 29.3 mg/g, a porosity of 98.13%, and a water contact angle of 130.5◦, exhibiting excellent oil/organic solvents sorption performance, with a high sorption capacity in the range of 25.4–36.5 g/g, approximately 5–16-fold higher than CSP, and with fast absorption speed and good reusability.
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•A facile top-down strategy to prepare cornstalk pith bioaerogel is investigated.•In-situ microfibrillation enhances sorption capacity from 4.2 to 36.5 g/g.•Cornstalk pith-based bioaerogel has a high porosity of 98.13%.•Silanization creates hydrophobicity (water contact angle = 130.5°).•The surface energy and liquid absorption coefficients are investigated.
In this study, malic acid-modified corn stalk pith (MA-CSP) was prepared as an environmentally friendly multi-functional bio-sorbent for adsorbing of dyes and oils. The sorption capacity of the ...MA-CSP for single and binary dyes is 328.46 mg/g - 566.27 mg/g. In addition, the MA-CSP also had good sorption for lubricating oil, soybean oil, diesel oil, and isopropyl alcohol, which were 37.2 g/g, 44.1 g/g, 33.8 g/g, and 29.3 g/g, respectively. Physical and statistical models were used to analyze the adsorption behavior of methylene blue (MB) and crystal violet (CV). And its sorption behavior for dyes was also affected by the co-existing salts in water. The sorption mechanism of the dye was mainly electrostatic attraction and hydrogen bonding action. The sorption of oil was primarily via the role of van der Waals force and hydrophobic interaction. The MA-CSP, as an eco-friendly, economical and efficient multi-functional sorbent, holds promise for effective dyes and oil removal from contaminated water, and its application in other fields is also highly anticipated.
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•Malic acid -modified corn stalk pith (MA-CSP) was synthesized as sorbent.•MA-CSP had an effective adsorption performance on dyes and oils.•Single and binary adsorption behaviors of dyes on MA-CSP was investigated.•Classical and statistical modeling were used to study adsorption mechanism.•Dye antagonistic adsorption was associated with statistical physics parameters.
Efficient separation of carbohydrates and lignin from lignocellulosic biomass, and further high-value conversion are still the main challenge of biorefinery. Oxygen-enhanced alkali treatment as a ...green method for separating polysaccharides and lignin from gramineous materials with environmental, economic and low energy consumption. Herein, oxygen-enhanced alkali technology was used to pretreatment corn stalk pith, and then realize high-value transformation. The results showed that oxygen-enhanced alkali treatment combined with acid precipitation, ethanol precipitation, enzymatic hydrolysis or ultrasonic can achieve clean, efficient separation and subsequent high-value transformation of various components of corn pith. The enzymatic efficiencies of solid and liquid polysaccharides were 75.42% and 50.52% respectively, and the structure of micro/nano-cellulose fiber is mostly flaky and granular. In addition, the separated lignin contains many small molecular compounds, which has the potential value of further utilization. In this study, oxygen-enhanced alkali treatment can achieve clean, efficient separation and subsequent high-value transformation of various components in corn stalk or lignocellulosic biomass, which has important practical significance.
Corn stalk pith, a low-cost organic material, was first utilized to produce hydrogen by photo-fermentation in a long tubular photobioreactor (PBR) with continuous mode. The effect of hydraulic ...retention time (HRT: 12, 18, 24, 30 and 36 h) on hydrogen production and light conversion in the tubular PBR was evaluated. The distributions of cell optical density, pH, sugar and soluble metabolites products (SMPs) along the tubular PBR (0 cm, 25 cm, 50 cm, 75 cm, and 100 cm from the inlet) were also assessed under different HRTs. The HRT of 24 h was found to be the optimum condition with the highest hydrogen production (2670 mL), yield (211.9 mL/L-medium), hydrogen production rate (38.4 mL/L/h), and light conversion efficiency (0.42%). In addition, statistical analysis revealed that cell optical density, pH value, sugar concentration and SMPs varied with different locations of the tubular PBR. Moreover, HRT of 24 h and 36 h accounted for 2.6–1.3% and 4.0–11.8% of the total SMPs in the effluent, respectively. Besides, acetic acid and butyric acid were the main SMPs in the effluent.
•Corn stalk pith was used for continuous photo-fermentative hydrogen production.•A long tubular PBR was employed as the vessel working without secession.•The optimum HRT was found to be 24 h.•The correlations between different locations and HRTs were evaluated.
The development of efficient and sustainable sorbents for emergent oil cleanup has attracted tremendous attention. In this study, the feasibility of enzymatic grafting of octadecylamine (ODA) on corn ...stalk pith (CSP) by laccase-TEMPO (2,2,6,6-tetramethylpiperidine-1-oxyl) treatment for enhanced oil–water separation was investigated. The dynamic contact angle tests suggest that the modified CSP (LCSP) had higher hydrophobicity (WCA, 157.2˚) and lipophilicity (OCA, 0˚) than the CSP did. In addition, the introduction of ODA onto the surface of modified CSP was verified by a variety of characterization techniques including SEM, FT-IR, and XPS. Compared with the control, laccase-TEMPO treatment of CSP coupled with octadecylamine grafting greatly improved the oil sorption capacity from 13.24 g/g to 44.25 g/g, while substantially reduced the water sorption capacity from 15.52 g/g to 2.76 g/g. LCSP has fast kinetic (sorption equilibrium reached before 60 min) and high fits to the pseudo-second-order kinetic model. The results obtained in this study reveal the feasibility of using Laccase-TEMPO treatment to graft the ODA onto the surface of CSP, thereby enhancing the rate and capacity of oil separation from oily water. The method and sorbent developed in this study hold promise for green, simple and cost-effective oil cleanup during oil spillage emergency events.
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•The sorption ability of corn stalk pith was enhanced after modification by laccase/TEMPO.•This sorbent achieves remarkable superhydrophobicity and superoleophilicity.•The maximum capacity for machine oil was found to be 44.25 g/g.•Surface hydrophobicity played an important role in the sorption process.•This work provides insight into the novel strategy of laccase-catalyzed octadecylamine functional modification.
Cellulose was extracted from corn stalk pith (CSP) and used for fabricating hybrid composite films with acceptable physical properties. As reinforced additives, low contents of graphene oxide (GO) ...and black phosphorene (BP), both ranging from 0.05 to 0.15 wt%, were separately incorporated into the cellulose matrix in a ZnCl2 aqueous system. A series of the composites were prepared via a regeneration process. The as-prepared composites showed various properties depending largely on the additive content, manner of processing, and the type of additive used. GO and BP nanosheets were homogeneously dispersed in the regenerated cellulose (RC), smoothly forming the dense films. Crystalline structures of RC-based films were revealed to be cellulose-II, and in addition to GO-crosslinked RC samples (RC-GO), an increase in the additive dosage led to a decrement in the crystallinity index of blended films (RC/GO and RC/BP). At 0.15 wt% additive amount, the RC-GO possessed superior thermal stability, tensile strength, and Young’s modulus, increasing 7.8%, 190.2%, and 79.0%, respectively, while the RC/BP exhibited a 3.5 times improvement in the elongation at break.
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