ACS Sustainable Resource Management最新文献

Growing environmental issues and dwindling global petroleum supplies have stimulated interest in biomass thermosets. The development of green and sustainable thermosets without the use of expensive raw materials and toxic solvents is a non-trivial challenge. Widely available shrimp and cellulose waste materials are cheap raw ingredients for the development of materials with excellent properties. Herein, we report fully biomass-derived dynamic imine thermosets, readily generated by reacting chitosan with a novel levoglucosenone diketone. The prepared imine thermosets exhibit enhanced modulus (3.7–7.9 GPa), high glass transition temperature (T_g) (171–176.1 °C) and tunable mechanical properties (tensile strength, 12.5 ± 3.5 to 21.1 ± 3.1 MPa). The as-prepared polymer demonstrated fast stress relaxation behavior and reprocessability owing to the dynamic nature of Schiff base bonds. At the “end of product life”, it can be decomposed in a home compost within 4–5 days. The material has the potential to replace conventional and environmentally destructive thermoset plastics, which currently dominate the market.

Utilizing waste resources enables sustainable circular economy strategies. The application of hydrochar in industrial wastewater treatment is usually limited due to poor porosity and surface area. This study addressed the critical need for heavy metal removal from industrial wastewater by developing an amino-functionalized hydrochar while offering sustainable resource recovery potential. The novel amino-functionalized hydrochar (NMHC) was derived from garden waste via a one-step hydrothermal process using nitric acid, tannic acid, and nicotinamide as modifiers. The adsorption batch experiment found that NMHC exhibited different adsorption behaviors for Cr(VI) and Mn(II) in sole and mixed systems. NMHC exhibited exceptional adsorption capacities of 245.0 mg/g for Cr(VI) and 183.9 mg/g for Mn(II), which were 3–4 times higher than those of unmodified hydrochar. The adsorption mechanisms analysis indicated that Cr(VI) removal involved synergistic adsorption and reduction to less toxic Cr(III) via oxygen-containing functional groups, while Mn(II) uptake relied on electrostatic interactions with nitrogen functionalities. Competitive adsorption in mixed systems revealed concentration-dependent inhibition, with Mn(II) displaying higher selectivity at elevated concentrations. NMHC demonstrated robust anti-interference capability against coexisting ions, maintaining >78% efficiency after five adsorption–desorption cycles. Practical validation using smelting wastewater confirmed NMHC performance under real conditions. This work shows that NMHC is a promising and environmentally friendly material for removing Cr(VI) and Mn(II) from wastewater.

A novel adsorbent was established from chemical packaging waste, embedded with magnetite and an organic framework named OFMCPW for Congo red (CR) scavenging and antibacterial performance. OFMCPW was characterized through BET surface area, PXRD, FTIR, pH_zpc, VSM, and SEM-EDX. SEM revealed a pebble-like porous surface, while EDX-elemental mapping confirmed C, N, O, Mg, Al, Si, S, and Fe existence. FTIR and XPS confirmed the magnetite, thiourea-based framework presence on the chemical packaging waste, and crystallinity was obtained from PXRD. Post-adsorption, the crystallinity of OFCPW decreased and closed pores were observed. The material exhibits a 17.929 m²/g surface area, 0.631 emu/g magnetic saturation, and 8.44 pH_zpc value. The maximum CR uptake of 154.526 mg/g was achieved under ambient conditions. The Freundlich model (R² = 0.999) and pseudo-second-order (R² = 0.996) model best matched the model. With endothermic (26.111 to 46.789 kJ/mol) and spontaneous (−0.980 to −7.589 kJ/mol) ways. 79.30% regeneration capacity was obtained in a methanol medium with 4-cycle reusability. OFMCPW treated industrial wastewater up to 56.23%. A secondary new adsorbent made from exhausted waste achieved a 73% uptake efficiency. OFMCPW inhibited Staphylococcus aureus and Escherichia coli with a 10 mm zone at 100 mg/mL, supporting the material’s efficiency in multiple applications and circular economy practices.

A hydrogen sensor utilizing proton-conducting ceramics was investigated for real-time monitoring of biohydrogen produced from soybean food wastewater using Clostridium neuense strain SDL48. Biohydrogen production began approximately 42 h after inoculation with strain SDL48, eventually reaching a concentration where hydrogen accounted for 43% of the gas phase. Additionally, the biohydrogen was purified using proton-conducting ceramics, successfully yielding hydrogen of high purity, qualifying it as pure hydrogen.

The ongoing climate change and global warming urge quick replacement of fossil fuels and demand innovative strategies for clean energy generation energy. The solar-induced photoelectrochemical water splitting mechanism holds immense potential for hydrogen generation through metal oxide photocatalysts. However, poor visible light absorption, aqueous instability, electrode degradation, and exciton recombination are major hurdles to its application. To address these challenges, we have employed p-type cuprous oxide (Cu₂O) electrodeposited on a conducting indium tin oxide (ITO) substrate to form a photoanode. The electrode was characterized systematically for its physicochemical and electrical properties. To facilitate solar to hydrogen conversion and enhance durability, we modified the electrode surface with chlorophyll. Owing to chlorophyll’s exceptional visible light absorption characteristics, the chlorophyll-modified Cu₂O electrode exhibited a remarkably high photocurrent density (3.26 mA/cm²) and energy conversion, yielding a 0.82% to 1.37% increase in the applied bias photon-to-current efficiency (ABPE %). Furthermore, density of states calculations validated the bonding interactions between Mg (chlorophyll) and O (Cu₂O) at the heterojunction. The electrode stabilities during the electrochemical reaction and post-electrochemical reaction were also compared, showing its potential applicability for hydrogen generation.

This study explores the improvement of CO₂ methanogenesis using microbial electrolysis systems (MESS) and ionic liquids (ILs). The microbial community adapted to CO₂ methanogenesis showed performance enhancement over time, achieving 0.46 mmol/cycle of specific methane production in the combined MESS and IL system, while it was around 0.28 mmol/cycle for MES only. Under non-electrified conditions, methane production was quite lower (0.1 mmol/cycle). The highest CO₂ conversion efficiency was achieved in the MESS/IL (M-I-E) group, followed by microbiology (M), MESS/IL (M-I), and MESS(M-E). ILs enhanced the electrochemical activity of MESS, resulting in a higher current to 0.61 ± 0.05 mA and a higher Coulombic efficiency to 68.8 ± 3%, compared to 0.45 ± 0.05 mA and 55.6 ± 2% for MESS alone. Further evidence for the improvements was shown by the reduced charge transfer resistance (2.37 ± 0.08 Ω) and enhanced biomass accumulation at the cathode. The microbial community analysis pointed out a significant shift in dominant species, including a significant increase in methanogens such as Methanobacterium sp. and Methanoculleus bourgensis. Metabolic responses showed upregulation of key genes involved in the transporters, Wood–Ljungdahl pathway, and tricarboxylic acid (TCA) cycle, indicating that IL layers could provide channels directly or through outside cellular entities for electrons to efficiently shuttle for enhanced methanogenesis. These findings gain insights into the synergistic benefits of ILs and MESS in boosting CO₂ methanogenesis and provide insights into the underlying mechanisms.

One of the major environmental challenges today is the effective removal of synthetic dyes from industrial wastewater. The current study developed a Fenton-like oxidation system mediated by Cr(III) and assisted by microwave radiation at 2.45 GHz to rapidly degrade Rhodamine B (RhB). The process achieved 98% RhB degradation in 90 s under ideal batch conditions, which included a pH of 6, 0.5 mM Cr(III), 19.4 mM H₂O₂, 0.07 mM RhB, and 520 W of microwave power. Total organic carbon analysis indicated that the system achieved 55% mineralization of RhB. The hydroxyl radical was identified by fluorescence spectroscopy as the primary reactive oxygen species in this process, and UV–visible studies examined degradation kinetics. Major intermediates, including oxalic acid, methanediol, and phthalic acid, were identified by GC–MS/MS. In comparison to RhB, toxicity evaluations using the EPA’s TEST software revealed that more than 80% of the degradation products were less toxic, nonbioaccumulative, and nonmutagenic. The process capitalizes on the circular reuse of Cr(III), a common industrial waste component, as a catalytic agent. Microwave irradiation improved reaction kinetics, expanded the pH range, and lowered energy input. Additionally, transient Cr(VI) formation provided a secondary catalytic cycle without persistent toxicity. Although moderate levels of Cr(VI) were observed after multiple reuse cycles (25 mg L^–1), these can be mitigated through post-treatment reduction, ensuring compliance with discharge regulations. These results position the Cr(III)-MW-Fenton system as a rapid, energy-efficient, and environmentally safe method for sustainable wastewater treatment.

Carbon dioxide reduction via electrochemical means offers a sustainable pathway to mitigate CO₂ emissions and synthesize value-added chemicals. Here, we report the synthesis and performance of a metal/polymer-carbon paper (Cu_xO_y/PoPD/CFP) electrode prepared via a simple two-step in situ electrodeposition method for the electrochemical CO₂ reduction reaction (CO₂ER). Unlike most reported catalysts that yield multiple liquid products and complicate downstream separation processes, Cu_xO_y/PoPD/CFP selectively produces formate as the sole liquid product across all of the test potentials. The amine-rich and porous PoPD matrix synergistically enhanced CO₂ capture, provided a conductive scaffold for efficient electron transfer, and facilitated intimate interfacial contact with copper oxides, enabling improved catalytic performance. The catalyst demonstrated an onset potential of ∼−0.27 V (vs RHE) and achieved a faradaic efficiency of 72.6% for formate with a current density of 6.70 mA/cm² at −0.80 V (vs RHE). Studies showcased an electrochemically active surface area (ECSA) of 16.625 cm² and a roughness factor of 8.31. The long-duration electrolysis experiment demonstrated stable performance for an extended period, maintaining continuous electrolysis for up to 9.5 h without significant fluctuations or degradation in activity.

In this paper, powder Li(NiCoAl)-x/Bi(K)OCl₆ and modular Li(NiCoAl)-5/Bi(K)OCl₆@PSA photocatalysts with unique oxidation properties were successfully constructed by a simple synthesis strategy using the cathode material Li(NiCoAl)O₂ of a retired lithium battery as a precursor. The as-prepared Li(NiCoAl)-x/Bi(K)OCl₆ powder photocatalysts show excellent photocatalytic oxidation abilities for degrading typical organic pollutants (OPs) in water and depolymerizing natural lignin to prepare vanillin due to their particular three-dimensional intercalated microstructures, unique photoelectric properties, and improved photogenerated carrier (e^––h⁺) separation efficiencies. The as-prepared Li(NiCoAl)-5/Bi(K)OCl₆@PSA modular photocatalyst is convenient to separate and recover and has similar photocatalytic oxidation ability to the corresponding powder photocatalyst, so it has potential application value. Compared with the photocatalytic oxidation process, potassium peroxymonosulfate (KHSO₅) can be activated by Ni⁺² and Co⁺² low-valence transition-metal elements in Li(NiCoAl)-x/Bi(K)OCl₆ and Li(NiCoAl)-5/Bi(K)OCl₆@PSA, so the target degradation objects can be degraded more quickly in the synergistic advanced oxidation process. The recycling experiments show that the as-prepared Li(NiCoAl)-5/Bi(K)OCl₆@PSA modular photocatalyst has a high performance stability.

As fossil fuels have finite resources and environmental drawbacks, there’s a growing interest in cleaner, renewable energy. Hydrogen (H₂) is seen as a promising alternative to petroleum due to its non-toxic, clean combustion that only produces water and avoids carbon dioxide emissions. In this study, different ratios of ZnFe₂O₄–CeO₂ nanopowder were synthesized via the glycine nitrate process (GNP). The ZnFe₂O₄–CeO₂ nanopowder catalyst was prepared by GNP, which was immensely porous and had a cotton-like structure. Moreover, the glycine nitrate process, which is a synthesis technology, can offer the advantages of low cost, simplicity, and speed and create a porous structure for the catalyst. The BET measurement revealed that the specific surface area of the as-combusted ZnFe₂O₄–CeO₂ nanopowder varied from 8.48 m²/g to 19.82 m²/g. Hydrogen production through the SRM process was monitored by using a gas chromatograph equipped with a thermal conductivity detector. The 20ZnFe₂O₄–80CeO₂ powder had the highest H₂ production without activation, reaching 7566.08 mL STP min^–1 g-cat^–1 at a reaction temperature of 550 °C achieved at an N₂ flow rate of 30 sccm. This study indicates that the glycine nitrate process imparts a porous structure to the catalyst, thereby increasing hydrogen production. Moreover, suitable incorporation of CeO₂ could improve the catalytic performance in the SRM process on hydrogen. Therefore, ZnFe₂O₄–CeO₂ nanopowders may have significant economic prospects.

Porous ZnFe₂O₄–CeO₂ nanopowders synthesized via glycine nitrate combustion effectively enhance hydrogen production from steam reforming of methanol, offering a promising, low-cost catalyst for sustainable energy applications.