ACS Sustainable Resource Management最新文献

There is a growing demand for the utilization of sustainable materials, such as cellulose-based alternatives, over fossil-based materials. However, the inherent drawbacks of cellulosic materials, such as extremely low wet strength and resistance to moisture, need significant improvements. Moreover, several of the commercially available wet-strength chemicals and hydrophobic agents for cellulosic material treatment are toxic or fossil-based (e.g., epichlorohydrin and fluorocarbons). Herein, we present an eco-friendly, high-yield, industrially relevant, and scalable method inspired by birch bark for fabricating hydrophobic and strong cellulosic materials. This was accomplished by combining simple surface modification of cellulosic fibers in water using colloidal particles of betulin, an abundant triterpene extracted from birch bark, with sustainable chemical engineering (e.g., lignin modification and hot-pressing). This led to a transformative process that not only altered the morphology of the cellulosic materials into a more dense and compact structure but also made them hydrophobic (contact angles of up to >130°) with the betulin particles undergoing polymorphic transformations from prismatic crystals (betulin III) to orthorhombic whiskers (betulin I). Significant synergistic effects are observed, resulting in a remarkable increase in wet strength (>1400%) of the produced hydrophobic cellulosic materials.

There is a growing demand for the utilization of sustainable materials, such as cellulose-based alternatives, over fossil-based materials. However, the inherent drawbacks of cellulosic materials, such as extremely low wet strength and resistance to moisture, need significant improvements. Moreover, several of the commercially available wet-strength chemicals and hydrophobic agents for cellulosic material treatment are toxic or fossil-based (e.g., epichlorohydrin and fluorocarbons). Herein, we present an eco-friendly, high-yield, industrially relevant, and scalable method inspired by birch bark for fabricating hydrophobic and strong cellulosic materials. This was accomplished by combining simple surface modification of cellulosic fibers in water using colloidal particles of betulin, an abundant triterpene extracted from birch bark, with sustainable chemical engineering (e.g., lignin modification and hot-pressing). This led to a transformative process that not only altered the morphology of the cellulosic materials into a more dense and compact structure but also made them hydrophobic (contact angles of up to >130°) with the betulin particles undergoing polymorphic transformations from prismatic crystals (betulin III) to orthorhombic whiskers (betulin I). Significant synergistic effects are observed, resulting in a remarkable increase in wet strength (>1400%) of the produced hydrophobic cellulosic materials.

This study presents a sustainable approach for dramatically enhancing the wet-strength and hydrophobicity of cellulosic materials by the synergistic combination of water-based betulin treatment, chemical modification, and hot-pressing.

Grape pomace (GP) is used as a fertilizer in viticulture due to its carbon (C) and nitrogen (N) richness. Its application follows as biologically treated (i.e., vermicompost) or as untreated (fresh), with different nutritional inputs for the soil. But constraints exist regarding the amount and mobility of nutrients as a function of the soil type and the short-term effects on the soil microbiota. In a 6 week microcosm study, we analyzed the C and N dynamics in two agricultural soils (loamy sand and silt loam) after fresh red or white GP application. Microbial responses including biomass, respiration, and ecophysiological indices were recorded at the end of the experiment. White GP increased the available C (dissolved organic carbon) in the soils compared to the control, with a greater availability in sandy loam compared to silt loam soil. Dissolved (available) N in the treated soils did not differ by GP variety or soil type, but values were lower than those in the controls, suggesting a rapid N assimilation. Red GP in the sandy loam soils accounted for the highest total phenolic content (TPC) compared to the white GP. Independently of the GP variety or treatment, values reached control levels after 6 weeks. In the GP treated soils, microbial C/N ratios were narrower compared to the controls. The ergosterol to microbial carbon ratio indicated a higher fungal fraction in the GP treated soils; in particular, in the sandy loam soil, that fits with the availability of nutrients in the respective soils. The GP treatment increased the ratios MBC:TC (microbial C:total C) and MBN:TN (microbial N:total N), independently of the GP variety but with larger ratios in the silt loam soil, indicative of nutrient immobilization. q_CO2 metabolic quotients were, in general, higher in the GP treated soils compared to the controls, with the highest values in sandy loam and red GP. The highest substrate utilization (respiration) rate was observed in the silty sandy soil, attributed mainly to the microbial biomass fraction compared to the sandy loam soil. But the functional diversity was not affected by the soil or by the GP treatment. We observed significant correlations between single chemical parameters and microbial indices apart from q_CO2, suggesting that the response of the microbiome is multifactorial but driven mainly by the composition of the GP and by the availability of nutrients which in turn depends on the soil properties. This study enables a broader understanding on the consequences of the application of fresh GP varieties in soils with different properties, which is necessary for calculations of optimal nutritional inputs.

Conversion and utilization of biowaste from the agriculture sector into useful value-added products have been of increasing interest in recent years. Special emphasis has been placed on the use of biowaste whey protein (WP) in packaging applications. In this study, WP from cheese production waste was investigated as potential material for developing films in combination with a synthetic water-soluble biopolymer poly(vinyl alcohol) (PVA) at WP contents ranging from 25 to 50 wt %. Morphology, structure, surface contact angle, and mechanical characteristics were evaluated to assess the relationship between blend composition and materials properties. WP content plays a significant role in determining the morphology of the films, with a high WP content leading to a less compact film. It leads to strong variations in the mechanical properties. The results of the electrical properties demonstrated that the electrical conductivity increases from 1.77 × 10^–11 S/cm for neat PVA to 2.06 × 10^–10 S/cm for the sample with 50 wt % WP, which is accompanied by variations in dielectric constant from 19.5 to 38 at 1 Hz, respectively. In addition, the presence of WP results in a low antibacterial activity, with the maximum bacterial growth inhibition for Staphylococcus aureus (22.2%) and Escherichia coli (11.5%) being obtained for PVA neat films. Finally, the degradation test revealed that after 146 days PVA neat reached 100% degradation in soil, while the sample with 50 wt % WP was only 47% degraded. Overall, the findings of this study contribute to advance toward the development of polymer blends from biowaste with tailorable characteristics for biodegradable electronic and packaging applications.

The synthesis of functional polymer materials from CO₂, an abundant and cheap feedstock, is of great significance from the viewpoint of green and sustainable development. Using CO₂ as monomer to produce functional polymeric materials can reduce not only fossil consumption but also CO₂ emissions. Herein, we designed a re-processable polyurea thermoset from formaldehyde and CO₂-based oligourea, which is an amino-terminated oligomer derived from CO₂ and 4,7,10-trioxa-1,13-tridecanediamine. The CO₂-based oligourea reacted with formaldehyde to form polyurea hemiaminal networks (PHNs) with a hemiaminal structure and reversible hydrogen bonds. PHNs are of good mechanical properties due to their intermolecular hydrogen bonds and cross-linked structure. Moreover, the reversible non-covalent hydrogen bonds and hemiaminal structure in the chains enabled PHNs to be re-processable. The synthesized polyurea thermoset can be hot-molded, the tensile strength is about 20 MPa, and the elongation at break is about 20% of the original sample. In addition, the tensile strength and toughness can be nearly recovered after hot-reprocessed for 6 cycles. This is the first report of the re-processable thermosetting polyurea from CO₂ designed by hydrogen bonds and hemiaminal cross-linking structure.

Bromelain is a potential proteolytic enzyme present in various parts of pineapple, having industrial importance with a wide range of applications. Present study focused on extraction, isolation, and purification of bromelain from pineapple peels waste as a feedstock. The proximate analysis of pineapple peel waste depicts the presence of about 7% protein in pineapple peel waste. Thus, several commercially available buffers were explored for the extraction of bromelain from pineapple peel. Of the tested buffers, sodium phosphate buffer showed the highest bromelain activity (0.75 CDU/mL) and protein concentration (0.160 mg/mL). The process intensification study is conducted to achieve maximum bromelain activity and maximum protein concentration. The optimized process provided maximum bromelain activity as 1.24 CDU/mL and maximum protein concentration of 0.130 mg/mL. The combination of ultrafiltration and adsorptive chromatographic purification was used to concentrate bromelain and to remove color components, respectively. It provides an increase in bromelain activity by 2.24-fold and protein concentration by 1.37 folds. Thus, the present study provides an efficient strategy for valorization of pineapple peel waste through extraction and purification of bromelain as a potential product.

This work aims to obtain allelochemical compounds from mucuna beans by applying subcritical water extraction (SWE). The influence of the water flow rate (solvent to beans ratio), temperature, and static time applied during extraction was evaluated in the removal of compounds of interest, with pressure fixed at 10 MPa. The application of water flow of 1 mL min^–1 (22.5 mL g^–1) provided greater removal of L-Dopa and total phenolic compounds (TPC). The temperature (120 °C) increased the extraction of L-Dopa, TPC, and total flavonoids (TF), providing greater antioxidant activity (AA). Furthermore, 20 min of static time preceding dynamic extraction promoted a percentage increase of ∼41.2% and ∼61.5% in the extraction of L-Dopa and TPC, respectively. In the profiled compounds, phenolic acids, flavonoids, and anthocyanins were the phytochemicals identified. The extract obtained under ideal conditions allowed a mass yield of ∼58.1 wt %, with active potential evaluated by levels of L-Dopa, TPC, and TF, as well as AA, validating the high antioxidant activity and suggesting allelopathic potential of the extract.

This study explores the obtaining of phytochemical compounds such as phenolic, flavonoids, and L-Dopa, which promote antioxidant activity with bioherbicidal potential from mucuna beans, through an extractive process using water under subcritical conditions.

The removal of tritiated water (HTO) from “ALPS-treated water” originating from the disabled Fukushima Daiichi Nuclear Power Plant (FDNPP) is an important environmental issue. In this paper, we report a new method of separating HTO from light water (H₂O) based on membrane distillation by gas–liquid exchange. HTO-containing water loaded on a hydrophobic membrane modified with a photothermal black dye was exposed to artificial sunlight. The heat generated from the dye upon sunlight exposure vaporized the water, with the HTO-containing water vapor penetrating through the membrane. The permeated HTO-containing water vapor was mixed with H₂O added to hydrophilic filters under the membrane. Gas–liquid exchange occurred in these filters and significantly decreased the percentage of HTO in the water collected under all filters. The increases in both the filter number and H₂O content in the hydrophilic filters increased the efficiency of HTO separation. When four hydrophilic filters containing H₂O and four hydrophobic filters were set alternately, the ratio of HTO collected under these filters decreased to 12 ± 0.3%. This process was also effective for the removal of ¹³⁷Cs from ¹³⁷Cs-containing water.

Exploring the intricate mechanism of factors coordinating with each other and optimizing the reaction conditions are critical to improving the performance of the hydrogen yield from biogas direct reforming (HY-B). Due to the lack of mature direct biogas hydrogen production engineering cases in China, the study data were obtained from a self-constructed HY-B unit that lasted for 42 days with a total of 298 data. In this study, an automated machine learning algorithm (AutoGluon) was used to comprehensively predict and analyze the parameters of HY-B. The study found that the optimal first-layer model is neural network (NN), and the optimal second-layer model is WeightedEnsemble. Meanwhile, based on the Shapley additive explanations (SHAP) values, it was demonstrated that the optimal parameter combination was a temperature range of 900–950 °C, pressure range of 0.15–0.3 bar, and water flow rate of around 24 g/h, which could give a distinguished conversion rate of CH₄ and hydrogen yield. In addition, the experimental verification showed that the Hydrogen-Seek strategy based on the multiobjective particle swarm optimization (MOPSO) could accurately excavate the best process parameters and optimize the combination of conditions and then result in significant improvements. The optimized data set can improve the yield from 63.45% to 67.69%, compared to the highest hydrogen yield in the previous experiment. Our results show that artificial intelligence algorithms can be successfully implemented to predict and improve HY-B performance, and hopefully provide guidance for the intelligent operation of industrial processes in the future.