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Natural polymers are attractive sustainable materials for production of fibers and composite materials. Cotton and flux are traditional plants used to produce textiles with comforting properties while technologies like Viscose, Lyocell and Ioncell-F allowed to extent fiber use into regenerated cellulose from wood. Neither natural nor man-made fibers completely satisfy the needs for cellulose based fabrics boosting development of new approaches to bring more sustainability into the fashion. Technologies like Spinnova are arising based on the spinning of mechanically pretreated cellulose materials with a lower environmental impact though challenged by the fiber quality and strength related to the inconsistency of the mechanical fibers. Nanoscaled cellulose is an excellent solution to improve the consistency of spin fibers, but charges introduced by traditional chemical treatments prevent rebuilding native hydrogen bonding and compromise the mechanical properties especially in wet conditions. We used nanocellulose with low surface charge isolated using reactive eutectic media to spin fibers able to restore the native hydrogen bonding and enable constitutional mechanical strength of cellulose. We performed un-optimized spinning to reveal the intrinsic properties of the fibers and confirmed the preserved strength of wet fibers compliant with the low surface charge enabling further engineering towards cotton-like fabric from wood. [ABSTRACT FROM AUTHOR]

Le Chatelier's principle is a basic rule in textbook defining the correlations of reaction activities and specific system parameters (like concentrations), serving as the guideline for regulating chemical/catalytic systems. Here we report a model system breaking this constraint in O2 electroreduction in mixed dioxygen. We unravel the central role of creating single-zinc vacancies in a crystal structure that leads to enzyme-like binding of the catalyst with enhanced selectivity to O2, shifting the reaction pathway from Langmuir-Hinshelwood to an upgraded triple-phase Eley-Rideal mechanism. The model system shows minute activity alteration of H2O2 yields (25.89~24.99 mol gcat−1 h−1) and Faradaic efficiencies (92.5%~89.3%) in the O2 levels of 100%~21% at the current density of 50~300 mA cm−2, which apparently violate macroscopic Le Chatelier's reaction kinetics. A standalone prototype device is built for high-rate H2O2 production from atmospheric air, achieving the highest Faradaic efficiencies of 87.8% at 320 mA cm−2, overtaking the state-of-the-art catalysts and approaching the theoretical limit for direct air electrolysis (~345.8 mA cm−2). Further techno-economics analyses display the use of atmospheric air feedstock affording 21.7% better economics as comparison to high-purity O2, achieving the lowest H2O2 capital cost of 0.3 $ Kg−1. Given the recent surge of demonstrations on tailoring chemical/catalytic systems based on the Le Chatelier's principle, the present finding would have general implications, allowing for leveraging systems "beyond" this classical rule. The principle of Le Chatelier is a fundamental concept in textbooks, serving as a guiding principle for controlling chemical and catalytic systems. In this study, the authors present an oxygen electroreduction system based on a single zinc vacancy catalyst, which operates in a manner that extends "beyond" Le Chatelier's principle. [ABSTRACT FROM AUTHOR]

Hydrothermal carbonization (HTC) converts wet biomass into hydrochar and a process liquid, but aromatic compounds in the products have been reported as a roadblock for soil applications as they can inhibit germination, plant growth, and soil microbial activity. Here, we compared HTC and hydrothermal humification (HTH) of cow manure digestate while varying the initial alkaline content by adding KOH. HTH converted 37.5 wt% of the feedstock to artificial humic acids (A-HAs) found in both solid and liquid, twice that of HTC. HTH reduced phenolic and furanic aromatic compounds by over 70% in solids and 90% in liquids. The A-HAs in HTH resemble natural humic acids (N-HA), based on FTIR, UV–vis spectra, and CHN and XRD analysis. The HTH liquid possesses 60% higher total organic carbon (TOC) than HTC. Although one-third of TOC can be precipitated as A-HA, a high TOC concentration remains in the liquid, which is shown to be mainly organic acids. Therefore, we also evaluated the HTC and HTH liquids for anaerobic biomethane production, and found that compared to the original cow manure digestate, the HTH liquids increased methane yield by 110.3 to 158.6%, a significant enhancement relative to the 17.2% increase seen with HTC liquid. The strong reduction in organic acids during biogas production from HTH liquid indicates the potential for converting soluble byproducts into methane, while maintaining high A-HAs levels in the solid product. Highlights: Hydrothermal humification of the digestate feedstock created about 37.5 wt% artificial humic acids in both solid and liquid phases. Increasing the alkaline content of the reaction media significantly decreased the aromatic content in the process liquid while increasing the concentration of organic acids and sugars. There was little to no gas production observed in the HTH process at higher alkaline contents, indicating carbon preservation in the liquid and solid phases. Anaerobic processing of the hydrothermal humification (HTH) process liquid resulted in a 158.6% increase in methane production compared to the primary biomass. The organic acid concentrations decreased after the anaerobic fermentation, while the main HTH product, artificial humic acids, remained nearly unchanged. [ABSTRACT FROM AUTHOR]

Herein, the feasibility of artificial black soil (ABS) derived from hydrothermal humification-hydrothermal carbonization (HTH-HTC) for restructuration of weak soil was verified. This study breaks through the long history of soil formation and evolution, and obtains reconstructed anthropogenic soil (AS) system which only takes one month, for the further application of rice seedlings. HTH-HTC derived by-products are slightly acidic, which facilitates the effective nutrient uptake and prevention of wilt diseases for acid-loving rice seedlings. AS mainly consists of the inherent components retained from weak soil such as SiO2 and minerals, and exogenous components such as artificial humic substances and hydrochar, as introduced by hydrothermal humification processes. Results exhibit that AS has high contents of ammonium nitrogen, organic matter, organic carbon, and abundant porous structure for nutrient transport and water holding, especially, the community diversity and richness of microbial system gets the expected recovery and new beneficial bacteria (such as Caballeronia calidae) or fungi (such as Humicola) appear. Positive effects of AS on agronomic traits in rice seedlings are quantified. As a general result, this study supports the application of AS in sustainable agriculture, and provides a novel strategy to tackle the already-omnipresent land degradation by anthropogenic misuse and larger scale accidents. Highlights: • Anthropogenic soil system was rapidly reconstructed through hydrothermal humification-hydrothermal carbonation technology. • Anthropogenic soil possesses multiple components-structure properties for nutrient transport and water retention. • Anthropogenic soil microbial systems recover and spread in 4 weeks. • Anthropogenic soil provides acidic environment to biochemically promote rice seedling growth. [ABSTRACT FROM AUTHOR]