Ethyl cellulose (EC) is a biocompatible, renewable, and recyclable material with diverse sources, making it an attractive candidate for industrial applications. Electrospinning has gained significant attention for the production of EC fibers. However, conventional electrospinning methods face challenges such as bead formation, low yield, and the absence of porous internal structures, limiting both the functional performance and scalability. This study presents an optimized approach for producing EC fibers by using a gravity-driven ultrahigh-speed electrospinning (GUHS-ES) system. This system leverages gravity to reshape the Taylor cone morphology during electrospinning, enhancing stability and dramatically increasing throughput. As flow rates increase, the Taylor cone contracts inward, while the tip structure expands and stabilizes, reaching maximum size at ultrahigh flow rates (100-150 mL/h). This unique Taylor cone structure enables a fiber production rate of 24.5 g/h, hundreds of times greater than conventional electrospinning techniques. Another advantage of the GUHS-ES system is its ability to achieve both high diameter uniformity and adjustable porosity. At ultrahigh flow rates, the pore sizes of the EC fibers reached 321 nm. The highly porous structure of EC fibers exhibited an absorption capacity of 56.6 to 110.7 times their weight, exceeding most previously reported oil-absorbing materials and demonstrating high efficacy for rapid waste oil absorption. This green, efficient technology represents a promising advancement for the large-scale production and application of natural polymer fibers with broad implications for sustainable industrial processes.

A novel mechanochemical approach is described for chloride-templated head-to-tail macrocyclization of a pentapeptide and a hexapeptide. This straightforward method allows the solvent-free preparation of cyclopeptides with yields comparable to solution-based approaches without the need for high dilution of the reaction mixture and with significantly reduced reaction times and organic waste amount.

Cellulose-derived biomaterials offer a sustainable and versatile platform for various applications. Enzymatic engineering of these fibers, particularly using lytic polysaccharide monooxygenases (LPMOs), shows promise due to the ability to introduce functional groups onto cellulose surfaces, potentially enabling further functionalization. However, harnessing LPMOs for fiber engineering remains challenging, partly because controlling the enzymatic reaction is difficult and partly because limited information is available about how LPMOs modify the fibers. In this study, we explored controlling LPMO-mediated fiber oxidation by sequentially adding a reductant (gallic acid, GA) and HO, using three different carbohydrate-binding module (CBM)-containing LPMOs. An in-depth analysis of the soluble products and the , , and carbonyl content in the fiber fraction indicates that fiber oxidation can indeed be controlled by adjusting the amount of GA and HO added to the reaction. In particular, at lower overall dosages of GA and HO, corresponding to low oxidation levels, fiber oxidation occurs rapidly with almost no release of soluble oxidized products. Conversely, at higher dosages, fiber oxidation levels off, while oxidized oligosaccharides continue to be released and the fibers are eroded. Importantly, next to demonstrating controlled fiber oxidation, this study shows that different cellulose-active LPMOs modify the fibers in different manners.

The isocyanate-derived fraction resulting as the bottom phase from the split-phase glycolysis of conventional polyurethane flexible foams has been given a new life based on the formation of amine-based polymers (polyureas and polyamides). For that purpose, the bottom phase was first hydrolyzed, producing toluenediamine and diethylene glycol, and further subjected to controlled vacuum distillation in order to recover both products separately. The hydrolysis reaction and the separation process conditions were determined and optimized, obtaining products with a purity comparable to that of commercial ones. Then, the recovered diethylene glycol was used in a new glycolysis process, obtaining a split-phase product with properties similar to those obtained using commercial diethylene glycol. Finally, the recovered toluenediamine was used in the synthesis of polyureas and polyamides. Both syntheses were modified with respect to the state of the art, replacing benzene with limonene in the synthesis of polyamides, which implies environmental improvements.

High-performance and sustainable membranes for water desalination applications are crucial to address the growing global demand for clean water. Concurrently, electrospinning has emerged as a versatile manufacturing method for fabricating nanofibrous membranes for membrane distillation. However, widespread adoption of electrospinning for processing water-insoluble polymers, such as fluoropolymers, is hindered by the reliance on hazardous organic solvents during production. Moreover, restrictions on industrial solvents are tightening as environmental regulations demand greener alternatives. This critical challenge is addressed here by demonstrating, for the first time, the fabrication of nanofibrous electrospun membranes of PVDF-HFP, poly(vinylidene fluoride)-co-hexafluoropropylene using a renewable, environment- and user-friendly solvent system containing Cyrene (dihydrolevoglucosenone), dimethyl sulfoxide, and dimethyl carbonate. The same solvent system was further used to produce nanocomposite graphene oxide (GO) and graphene nanoplatelet (GNP)-containing nanofibrous electrospun membranes. When tested for water desalination via membrane distillation, these membranes either outperformed or matched the performance of those produced with hazardous organic solvents, achieving salt rejection rates of >99.84% and long-term stability. The economic viability of the green solvent system was further validated through Monte Carlo simulations. This work demonstrates the potential to move fluoropolymer electrospinning from dimethylformamide-based systems to greener alternatives, enabling the consistent production of high-quality nanofibrous membranes. These findings pave the way for more sustainable manufacturing practices in membrane technology, specifically for water desalination via membrane distillation.

Direct conversion of point-source CO into fine chemicals over cooperative and bifunctional materials (BFMs) - composed of adsorbents and catalysts - has emerged as a promising approach to improve the energy efficiency of the carbon capture and conversion processes. In this study, a bifunctional material consisting of CrO/ZSM-5 catalyst and CaO adsorbent was developed and tested in the CO-oxidative dehydrogenation of propane (CO-ODHP) for reactive capture of CO in a fixed bed reactor. First, CaO was prepared using two distinct methods: solid-state and citrate sol-gel. The citrate sol-gel method resulted in small and finely-distributed CaO particles, allowing more accessible sites for CO adsorption. Consequently, a high CO adsorption capacity of ∼14 mmol/g was achieved with fast adsorption kinetics compared to CaO prepared by the solid-state method. The CaO adsorbent was then combined with the CrO/ZSM-5 catalyst for BFM synthesis and tested in the CO-ODHP process, targeting propylene production. The BFM was extensively characterized to provide insights into the BFM's surface chemistry, morphology, and reaction mechanism in the reactive capture process of CO-ODHP. The results revealed that under isothermal adsorption-reaction conditions at 600 °C, a propane conversion of 22.5%, a propylene selectivity of 55.3%, and an olefin selectivity of 67.3% were achieved. The excellent propylene selectivity was attributed to the catalyst acidity and redox property of the CrO/ZSM-5 catalyst, which facilitated the reaction pathway of propane dehydrogenation in the process of CO-ODHP. Overall, this study renders CrO/ZSM-5@CaO as promising BFMs with high CO capture capacity and catalytic activity for integrated CO capture and conversion in the ODHP reaction.

Tannins from (black wattle) are one of the few industrially available sources of nonlignin polyphenols. The intrinsic chemical heterogeneity and high dispersity of industrial tannins complicate their use in applications where the reactivity or colloidal interactions need to be precisely controlled. Here, we employ a solubility-centered sequential fractionation to obtain homogeneous tannin fractions with a dispersity index lower than 2. The well-defined and homogeneous fractions were characterized using NMR and MALDI-TOF and were used to prepare Pickering emulsions by costabilization with chitin nanofibrils. We demonstrate that the emulsion droplet size and associated properties can be tuned by using tannin fractions of varied molar mass, which is a result of fine control over the tannin-chitin complexation interactions at the oil-water interface. In addition to enhancing emulsion stability, the addition of tannin to chitin-stabilized Pickering emulsions has proven to be a viable strategy for engineering the emulsion's viscoelastic properties, as well as introducing antioxidative properties. Overall, we demonstrate a facile method to finely control the properties of industrial tannins and enable their customization to allow their utilization in high-performance multiphase systems.

This study evaluated an innovative strategy for valorizing grape stems (GS) from the winery industry as an animal feed ingredient from both environmental life-cycle and economic perspectives. Two processes for GS-based feed ingredient production were compared: one using hydrolyzed GS and the other using nonhydrolyzed GS, alongside the conventional animal feed production process. Using primary pilot-scale data for GS-based feed ingredient production and secondary data for animal feed production, life-cycle assessments, and economic analyses were conducted. Results showed that hydrolyzing GS leads to 3.8 times higher impacts on human health compared to the nonhydrolyzed variant, primarily due to NaOH and electricity usage, although this difference becomes negligible at the animal feed production stage. Incorporating GS-based feed ingredients was found to reduce the environmental impacts of animal feeds, primarily due to reductions in other ingredients. Economically, producing nonhydrolyzed GS-based feed ingredient proved more feasible, with a net present value of €-106,766 for a plant with a capacity of 1000 kg/d. GS valorization scenarios yield lower environmental impacts than landfilling and composting, although not compared to incineration, which offers notable energy recovery potential. This study suggests adopting GS valorization in animal husbandry to support a circular economy, providing insights for stakeholders.

A hollow cathode discharge with a copper nickel cathode (Cu50Ni50) was operated in an Ar/H/N gas mixture. Optical emission spectroscopy revealed the formation of NH radicals, which serve as precursors for NH formation. Ion mass spectrometry showed the formation of NH and NH ions indicating NH formation. Gas samples taken at the exhaust of the vacuum system were analyzed by Fourier transform infrared spectroscopy. Clear evidence for NH formation was obtained from these measurements.

As the world's technological development shifts toward a sustainable energy future by harnessing renewable energy sources, ammonia is gaining recognition as a complementary green vector to hydrogen. This energy-dense carbon-neutral fuel is capable of overcoming hydrogen's limitations in terms of storage, distribution, and infrastructure deployment. The biggest challenge to the global use of ammonia as an energy storage medium remains more efficient, readily deployable production of ammonia from abundant, yet intermittent, sources. Green decentralized ammonia production, which refers to the small-scale, localized ammonia production utilizing environmentally sustainable methods, offers a promising approach to overcoming the challenges of traditional ammonia synthesis. The process aims to minimize carbon emissions, increase energy efficiency, and improve accessibility to ammonia in remote regions. Ammonia separation using sorbent materials holds significant potential in green ammonia production, providing a viable alternative to conventional condensation-based separation methods, with particular benefits in improving energy efficiency. This perspective summarizes recent developments in the field of ammonia separation, focusing on newly developed sorbents for the integrated ammonia synthesis-separation process, particularly metal halides that could potentially replace a conventional ammonia condenser. The challenges and potential solutions are also discussed. Moreover, this perspective outlines the mechanism of ammonia absorption into metal halides with its kinetics and thermodynamics. The use of computational methods for the development of new materials is also described, thereby laying the foundations of green ammonia technology.

γ-Valerolactone (GVL) is a versatile chemical derived from biomass, known for its uses such as a sustainable and environmentally friendly solvent, a fuel additive, and a building block for renewable polymers and fuels. Researchers are keenly interested in the catalytic transfer hydrogenation of levulinic acid and its esters as a method to produce GVL. This approach eliminates the need for H pressure and costly metal catalysts, improving the safety, cost effectiveness and environmental sustainability of the process. Our Perspective highlights recent advancements in this field, particularly with respect to catalyst development, categorizing them according to catalyst types, including zirconia-based, zeolites, precious metals, and nonprecious metal catalysts. We discuss factors such as reaction conditions, catalyst characteristics, and hydrogen donors and outline challenges and future research directions in this popular area of research.

An enzyme-catalyzed synthesis of rhododendrol, an intermediate in the production of raspberry ketone, was investigated. The approach involves the enzymatic hydrolysis of rhododendrol glycosides into rhododendrol and a glycosidic residue. Rhododendrol glycosides, which are naturally derived from the inner bark of birch trees-a renewable resource-vary considerably in composition depending on the origin of the plants. In this study, mixtures of betuloside and apiosylrhododendrin from natural resources were used in different proportions. An in-depth study was conducted to assess the feasibility of the process. A mathematical model was developed based on studies of the kinetics and operational stability of the enzyme. The model for betuloside hydrolysis catalyzed by β-glucosidase was validated in batch, repetitive batch, and ultrafiltration membrane reactors. The highest productivity, ranging from 83.9 to 94.5 g L day, was achieved in the latter. After screening nearly 50 enzymes, RAPIDASE emerged as a solution for the hydrolysis of apiosylrhododendrin, and the model was validated in a batch reactor. Model-based optimization enabled the prediction of input parameters for different compositions of biogenic rhododendrol glycosides to obtain consistent process output metrics.

The reductive catalytic fractionation (RCF) of second generation lignocellulosic biomass is an elegant one-pot process to obtain a highly delignified cellulose pulp, sugar-derived polyols, and depolymerized and stabilized lignin oils. However, the need of noble metal catalysts to prompt the reactions may impact the economic sustainability of the overall "lignin-first" biorefinery if the catalyst recovery and recyclability are not guaranteed. Herein, the use of a novel catalyst based on supported ruthenium over maghemite for the RCF of poplar sawdust is reported for the first time. This material allows us to obtain a pure cellulose pulp with a quantitative magnetic recovery efficiency after the first cycle. The obtained lignin oil is composed by a 12% yield in phenolic monomers (i.e., benzyl alcohol, 4--propylguaiacol, and 4--propylsyringol), together with dimers and trimers as confirmed by GPC analyses. The catalytic material was found to be stable and recyclable for three reaction cycles with only minor loss of RCF efficiency. On the other hand, the straightforward, lab-scale, magnetic recovery procedure needs to be further improved in the future to ensure quantitative recovery of the catalyst also after several RCF cycles.

To be implemented on climate-relevant scales, direct air capture of CO (DAC) will require large capital-intensive facilities and careful attention to cost minimization. In making decisions among potential sites for DAC facilities, all of the factors that will impact process cost and efficiency should be considered. In this paper we focus on a factor that has previously received little attention in the DAC community, namely variations in atmospheric conditions on hourly time scales and length scales of meters. We present data curated from extensive previous studies of biosphere-atmosphere fluxes with observations of CO concentration, temperature, and relative humidity (RH) with hourly resolution from many sites in North America. These include locations where typical diurnal variations in CO concentration during summer months exceeds 150 ppm. These variations are larger than the seasonal variations that exist between averaged CO concentrations in winter and summer, and they are highly correlated with diurnal variations in temperature and RH. Diurnal variations are dependent on the height above ground at which CO concentrations are measured, with smaller variations existing at heights of 10 m or more than at ground level. We illustrate the potential implications of these short-term variations for the operation and optimization of a DAC process with process-level calculations for a specific adsorption-based process using amine-rich adsorbents.

Identifying improved and sustainable alternatives to "classic" separation techniques is an active research field due to its potential widespread impact in fundamental and applied chemistry. As basic purification methodologies, like liquid-liquid extraction, undergo continuous refinement by chemists and engineers, identifying new conditions that outperform existing techniques can be difficult. A major contributor to this challenging problem is the need to explore a vast experimental space to identify the precise conditions that optimize the separation procedure. The advent of artificial intelligence and the advancement of robotic technologies offer the potential to shift the traditional design paradigm. Toward that end, we applied a combination of Bayesian Optimization and high-throughput robotic experiments on the liquid-liquid extraction of thorium (Th) and demonstrated that this approach speeds up discovery and significantly accelerates the optimization process. By using Bayesian Optimization as a guide, our automated instrument carried out a total of 339 distribution ratio measurements, corresponding to 113 unique conditions, identifying the optimal experimental conditions with reduced experimental efforts by an estimated 74% compared to a traditional full screening approach. This time and cost saving is particularly significant for radioactive materials, as it not only is more economical and sustainable but also minimizes human exposure to radioactivity.

Magnesia-based cement is recognized for its outstanding mechanical properties, but its environmental impact has not been thoroughly evaluated. This paper employs a comprehensive life cycle assessment methodology to systematically analyze the environmental effects of four kinds of MgO and 10 kinds of magnesia-based cements based on the data in the literature. The impacts include CO emissions, fossil fuel depletion potential, and overall environmental impact indicators. The results indicate that using Salt Lake magnesium residue to prepare MgO, e.g., LB-MgO and DB-MgO, can reduce over 60% of CO emissions, compared with traditional MgO (e.g., L-MgO and D-MgO) prepared with magnesite. Utilizing supplementary cementitious materials (e.g., fly ash and ground granulated blast-furnace slag) as substitutes for clinker in basic sulfate magnesium cement (BMSC) and magnesium phosphate potassium cement (MKPC) can also reduce approximately 16 and 45% of carbon emissions, respectively. In addition, carbonation-reactive magnesium cement (CRMC), which involves carbonation curing and replacing traditional MgO with Salt Lake magnesium residue, is the most environmentally friendly magnesia-based cement with an overall environmental impact indicator of 0.00078.

The separation of lignocellulose into lignin, cellulose, and hemicellulose without significantly altering the chemical structures of these component biopolymers remains a modern chemical challenge. Lignin, in particular, has potential as a highly valuable feedstock material but remains underutilized due to the difficulty of generating lignin with low modification and condensation. This work investigates the lignin-rich solids ("boron lignin") generated from a previously reported boron Lewis acid-mediated lignocellulose separation and concludes that (1) boron Lewis acid extraction removes 80-85% of carbohydrates from the original lignocellulose sample, and (2) the resulting lignin possesses a low condensation level and high similarity to native lignin structure. Residual carbohydrate assessment, depolymerization efficiency analyses, heteronuclear single quantum coherence (HSQC) and solid-state nuclear magnetic resonance (NMR) analyses are discussed, including benchmarking results with alternate lignin sources known to possess low and high condensation levels. Further, two different wood sources (white pine, a softwood, and beechwood, a hardwood) were employed to generate lignin samples. Depolymerization of a white pine-derived boron-lignin produced 47% (±9.5) of extractable monomers, which compares well to a state-of-the-art method to generate low condensed lignin (56 ± 7.8%). An unexpected instability of the oil sample was observed following hydrogenolysis of boron lignin generated from beechwood. Dramatic color changes coupled with precipitation and lowered monomer yields were observed when samples were aged (11% decrease) or concentrated (30% decrease). Based on NMR spectroscopic analyses, this instability is postulated to arise due to boron-mediated demethylation of methoxy sites on the lignin scaffold.

The design of new hydrophobic solvents is essential for replacing the toxic hexane for extracting nonpolar compounds such as fatty acids. On the other hand, the full use of plant matrices seeking to obtain new food and pharmaceutical products from their coproducts has also been the focus of sustainable processes. This study proposed new solvents for replacing hexane to extract fatty acids and hydrophobic bioactive compounds from coproducts obtained from almond- and peanut-based milk processing. The COSMO-RS method was used to select terpene-based mixtures to substitute hexane. Experimentally, four liquid solvents were formed from 1:2 tetradecanol/1,8-cineole (TE/EU), 1:2 camphor/1,8-cineole (CA/EU), 1:1 oleic acid/1,8-cineole (OL/EU), and 1:1 menthol/1,8-cineole (ME/EU). DSC analyses indicated the reduction of the CA/EU, OL/EU, and ME/EU melting points concerning their components. However, the melting point values predicted by the COSMO for obtaining eutectic mixtures differed. CA/EU was the only mixture with a melting point lower than the COSMO-RS-predicted one. In contrast, the FTIR spectra did not provide a clear visualization of the hydrogen bond formation between camphor and 1,8-cineole. This could be due to the formation of weak hydrogen bonds, a phenomenon observed in other studies. Nevertheless, these solvents have the advantage of low viscosity, a promising feature that likely facilitated mass transfer in the extraction of hydrophobic compounds from almond and peanut coproducts. ME/EU provided the same global extraction yield as hexane and higher phytosterol extraction from almond coproducts. On the other hand, CA/EU provided the same global yield and squalene content as hexane from peanut coproducts. The extracts can be directly used in food and pharmaceutical applications since the solvents are usually part of the formulations. However, DSC and TGA-DTA analyses indicated possible ways to separate the solvents.

Limestone (calcite, CaCO) is an abundant and cost-effective source of calcium oxide (CaO) for cement and lime production. However, the thermochemical decomposition of limestone (∼800 °C, 1 bar) to produce lime (CaO) results in substantial carbon dioxide (CO) emissions and energy use, i.e., ∼1 tonne [t] of CO and ∼1.4 MWh per t of CaO produced. Here, we describe a new pathway to use CaCO as a Ca source to make hydrated lime (portlandite, Ca(OH)) at ambient conditions (, )-while nearly eliminating process CO emissions (as low as 1.5 mol. % of the CO in the precursor CaCO, equivalent to 9 kg of CO per t of Ca(OH))-within an aqueous flow-electrolysis/pH-swing process that coproduces hydrogen (H) and oxygen (O). Because Ca(OH) is a zero-carbon precursor for cement and lime production, this approach represents a significant advancement in the production of zero-carbon cement. The rbon ime (ZeroCAL) process includes dissolution, separation/recovery, and electrolysis stages according to the following steps: (Step 1) chelator (e.g., ethylenediaminetetraacetic acid, EDTA)-promoted dissolution of CaCO and complexation of Ca under basic (>pH 9) conditions, (Step 2a) Ca enrichment and separation using nanofiltration (NF), which allows separation of the Ca-EDTA complex from the accompanying bicarbonate (HCO ) species, (Step 2b) acidity-promoted decomplexation of Ca from EDTA, which allows near-complete chelator recovery and the formation of a Ca-enriched stream, and (Step 3) rapid precipitation of Ca(OH) from the Ca-enriched stream using electrolytically produced alkalinity. These reactions can be conducted in a seawater matrix yielding coproducts including hydrochloric acid (HCl) and sodium bicarbonate (NaHCO), resulting from electrolysis and limestone dissolution, respectively. Careful analysis of the reaction stoichiometries and energy balances indicates that approximately 1.35 t of CaCO, 1.09 t of water, 0.79 t of sodium chloride (NaCl), and ∼2 MWh of electrical energy are required to produce 1 t of Ca(OH), with significant opportunity for process intensification. This approach has major implications for decarbonizing cement production within a paradigm that emphasizes the use of existing cement plants and electrification of industrial operations, while also creating approaches for alkalinity production that enable cost-effective and scalable CO mineralization via Ca(OH) carbonation.

A novel-biobased latex was synthesized by redox-initiated emulsion copolymerization of ethoxy dihydroeugenyl methacrylate with 5 wt % of a photosensitive methacrylate containing a coumarin group. A stable copolymer latex having 16 wt % solids content and a particle size of 53 nm was obtained. The copolymer had a of 29 °C and was soluble in acetone. Coatings were obtained, and the effect of UVA irradiation was tested: the light-induced cross-linking of the copolymer by [2 + 2] cycloaddition of the coumarin pendant moieties was demonstrated by UV-visible spectroscopy. As a consequence of UVA-induced cross-linking, the copolymer became insoluble in acetone. The copolymer latex was combined with hemp-derived nanocellulose to obtain composite self-standing films by simple mixing in an aqueous medium followed by casting, evaporation of water, and hot pressing. The composite films were also successfully cross-linked by [2 + 2] cycloaddition, with an enhancement of barrier properties. The water vapor transmission rate of the cross-linked composite films with up to 45 wt % nanocellulose was 5 times lower than that of the hemp nanocellulose film, while further addition of nanocellulose increased permeability.

CeO nanoparticles exhibit potential as solid adsorbents for carbon dioxide (CO) capture and storage (CCS), offering precise control over various facets and enhancing their efficiency. This study investigated the adsorption and desorption behaviors of two types of CeO nanoparticles: cubic CeO with primarily {001} facets and polyhedral CeO with mainly {111} facets. The results showed that despite polyhedral CeO's lower quantity, it demonstrated successful adsorption-desorption cycles in both oxidized and reduced states. However, reduced CeO exhibited a higher adsorption capacity but displayed irreversible adsorption-desorption cycles. Reversible adsorption occurred through weak bond formation with CO, while cubic CeO with a high oxygen vacancy concentration exhibited irreversible adsorption due to strong bond formation. These insights contribute significantly to understanding CeO nanoparticle characteristics and their impact on the CO adsorption and desorption processes, aiding in the development of advanced CCS techniques.