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Over the past few years, the proliferation of lithium-ion batteries (LIBs) as pivotal energy storage solutions has surged dramatically. However, this widespread adoption has come with a significant downside: the accumulation of substantial quantities of discarded LIBs. From the perspective of green production and industrial development, the problem of recycling spent LIBs urgently needs to be addressed. Based on the physicochemical properties of ionic liquids (ILs) and deep eutectic solvents (DESs), as well as their potential in LIB recycling, this paper proposes the concept of the Ionic Liquid System, including ILs and DESs. The aim is to systematically outline the application of the Ionic Liquid System in the LIB recycling industry. Ionic Liquid System reagents are considered environmentally friendly green solvents due to their biodegradability. Here, we discuss laboratory research on the recovery of spent LIBs using similar system solvents based on studies reported over the past decade and categorize recent laboratory work, while evaluating the advantages and disadvantages of the application of the Ionic Liquid System. This article explicitly provides an effective reference for recycling spent LIBs through the Ionic Liquid System and prospects for future work on recycling spent lithium batteries. [ABSTRACT FROM AUTHOR]

Sustainable production of 1,4-pentanediol (1,4-PDO) from biomass is of great importance because 1,4-PDO is a monomer of degradable polyesters and plastics. This paper reviews the conversion of biomass-derived levulinic acid (LA) and furfural as well as their derivatives alkyl levulinate, γ-valerolactone (GVL) and furfuryl alcohol (FAL) into 1,4-PDO. MoOx or ReOx modified noble metal catalysts and non-noble metal catalysts with core–shell and alloy structures show a high 1,4-PDO yield and stability in LA hydrogenation under severe hydrothermal conditions. The conversion of furfural to 1,4-PDO involves the initial C＝O bond hydrogenation to form FAL, the consecutive acid-catalyzed ring-opening and the final hydrogenation. Therefore, it needs a bifunctional catalyst composed of metallic species and acid sites to improve the 1,4-PDO yield. Efforts are made here to highlight the employed catalysts, structure–performance relationship, reaction pathway and reaction mechanism in detail. The current challenges for large-scale applications of conversion of LA and furfural to 1,4-PDO have been proposed, including process development, catalyst cost, solvent and active site distribution. We believe that this review will provide new opportunities and expand the options for the production of 1,4-PDO via biorefining processes. [ABSTRACT FROM AUTHOR]

A comprehensive decarbonization approach is reported, involving Direct Separation Reactors (DSRs) and eco-efficient energy sources in the production of hydrated lime. Environmental and economic impacts are calculated through an in-depth life-cycle cradle-to-grave assessment. Integrating a DSR kiln with carbon capture technologies (CCTs) attained a remarkable 65% reduction of CO2 emissions during hydrated lime production, with a minimum environmental impact from the CCT itself. Fully electrified DSR kilns, powered by renewable energy sources, achieve an astonishing 94% decrease in CO2 emissions when compared to conventional reference scenarios, all without adverse environmental effects. In limebased plasters, combining DSR kilns, natural carbonation, and eco-efficient energy sources, particularly with the inclusion of natural gas, leads to carbon negativity. This efficiently offsets all production emissions and even cuts back an additional 30%. In the case of fully electrified DSR kilns, the results are a remarkable 149% CO2 emission reduction throughout the entire cradle-to-grave lifecycle. Carbon capture technologies reduce carbon tax costs by up to 26%, thereby enhancing the economic sustainability of these endeavours. To realize a swift and effective decarbonization of the lime industry, a harmonized effort is imperative and involves balancing the interests of the private sector, environmental protection, and promoting societal well-being, all within a supportive regulatory framework. [ABSTRACT FROM AUTHOR]

The electrochemical oxygen reduction reaction (ORR) via a selective 2e− pathway offers a great opportunity for the synthesis of H2O2 as an alternative to the traditional anthraquinone route. Unfortunately, the cell voltage of H2O2 electrosynthesis at neutral conditions still requires improvement to meet industrial demands, where high H2O2 productivity and low input energy are desired. Crucial impacts of each reactor component on the relationship of cell voltage and current density, and the over-potentials of each part of a flow cell reactor for H2O2 electrosynthesis are investigated in this research, which indicates that the overpotential of the cathodic solution has a great contribution to the cell voltage. When applying a 0.3 mm cathodic solution channel in the flow cell reactor, H2O2 is successfully synthesized at a cell voltage of 2.28 V with a current density of 300 mA cm−2 and 97.1% faradaic efficiency. This corresponds to a 3.70 kW h kg−1 H2O2 energy consumption, which is much lower than results in recent reports in the literature. The produced H2O2 can be directly used for synthesizing high-purity 2,2′-dibenzothiazole disulfide (MBTS) in nearly 100% yield, showing the potential industrial value of H2O2 electrosynthesis technology. [ABSTRACT FROM AUTHOR]

This paper reports an innovative work on the green production of furfural using a covalent organic framework (COF), thereby expanding the range of catalysts in the furfural manufacturing industry and achieving efficient production of furfural from sustainable biomass-derived sugars. The research results will provide a theoretical basis for the green and sustainable production of furfural. [ABSTRACT FROM AUTHOR]

Existing polyethylene glycol (PEG)-based phase change materials (PCMs) with recyclability are not chemically recyclable because the raw materials of the PCMs cannot be obtained after recycling. Herein, we used a facile method to prepare a PEG-based form-stable PCM (FSPCM) using mannitol as the supporting material. The intermolecular hydrogen bonding between mannitol and PEG is strong, which gives rise to a PCM solid state even at 90 °C and prevents the leakage that normally occurs with pure PEG. More importantly, the FSPCM can be chemically recycled using butyl acetate, which is a satisfactory solvent for PEG but cannot dissolve mannitol. Thus, PEG and mannitol are obtained, with recycling rates greater than 90% for each. Additionally, there are high latent heat values for this PEG-based FSPCM, as well as excellent thermal stability and thermal reliability, suggesting the remarkable ability for thermal energy storage and thermal management. [ABSTRACT FROM AUTHOR]

Recently, poly(ionic liquid)s (PILs) have emerged as a family of polymeric materials which are being increasingly investigated for interdisciplinary applications. Their high electrical conductivity, excellent thermal/mechanical stability, low vapor pressure, and easy processibility render PILs exceptionally attractive as versatile platforms for green chemistry. Recent decades have witnessed fruitful efforts devoted to the development of PIL-based green chemistry platforms, achieving significant discoveries that will unfold their uniqueness in catalysis, separation, sensors, electrolyte, and functional materials. However, few review papers offer comprehensive discussion on PILs' application in the green chemistry field. In this review, we initially introduce the structure and types of PILs, which is followed by a systematical summary of the synthesis of PILs in terms of direct polymerization of monomer, polymerization after monomer modification, and modification of polymers. Furthermore, several aspects of the application of PILs related to green chemistry are highlighted, such as sensors, separation, catalysis, electrolytes for energy storage devices, and as versatile precursors yielding functional materials. Current challenges and corresponding research directions in PILs for green chemistry are clarified, to make PILs truly green platforms for existing technologies. [ABSTRACT FROM AUTHOR]

Although the combination of halide perovskite photocatalysts and plasma ensures the effective conversion of CO2, there is still much room to improve its conversion ratio and energy efficiency. The traditional experimental trial-and-error method is extremely demanding for researchers in each experimental operation and result analysis, while the experiments greatly consume time and raw materials and require complex equipment. In this paper, for the first time, we modeled the process of CO2 conversion synergistically driven by dielectric barrier discharge (DBD) plasma and a Cs2TeCl6 photocatalyst via machine learning. K-fold cross-validation combined with the coefficient of determination (R2) was used to evaluate the regression algorithms, and the BPANN with the best performance was selected to establish a model for predicting the CO2 conversion ratio and energy efficiency. In order to make the predictions more accurate, genetic algorithms, particle swarm optimization and Bayesian optimization were applied to improve the hyperparameters of the neural network, and the GA-BPANN model achieved an R² of 0.9713 and 0.9622 on the training and testing sets, respectively, while its practical application was also demonstrated. In addition, the effect of each process parameter on conversion efficiency was quantified by the Spearman correlation coefficients, which could provide insights into the roles of different process parameters in CO2 conversion. This work provides a new approach for boosting CO2 conversion, which could facilitate future experimental design and process optimization to promote carbon dioxide utilization. [ABSTRACT FROM AUTHOR]

Pure subcritical water autohydrolysis is an economical and green biorefinery method and potentially applicable technology. Elucidating and regulating the energy input effects on the structural dissociation and chemical depolymerization of lignocellulosic biomass will progress the industrialization of pure subcritical water autohydrolysis biorefineries. In this work, a method for determining the degree of tissue dissociation was invented. Combined with the analysis of the microstructure, ultrastructure, chemical composition, and aggregation state, this paper reveals the process and mechanism of the P-factor effect as an energy input measurement on the bio-structural dissociation and chemical depolymerization during naked oat stem autohydrolysis. A method of using the P-factor to regulate the biostructural dissociation and chemical depolymerization was developed. For the first time, a critical point for the autohydrolysis of naked oat stem in pure subcritical water between 170–210 °C was found to be at a P-factor = 233, around which an essential change in biostructural dissociation and chemical depolymerization occurred. The findings indicate that the control of naked oat-stem tissue and cell dissociation, ultrastructure, and chemical depolymerization can be accomplished using the P-factor as an energy input measurement for autohydrolysis. The revealed mechanism and method created in this study enable the stepwise separation of gramineae tissues, cells, and major chemical components, enabling a full-composition multi-purpose biorefinery of lignocellulose. [ABSTRACT FROM AUTHOR]

The existing methods for obtaining titanium are harmful as toxic organic solvents must be used. In this paper, three magnetic ionic liquids (MILs) and five hydrophobic deep eutectic solvents (HDESs) were designed and combined for safer extraction of titanium from an HCl leachate of ilmenite (HLI). First, the physicochemical properties including density, viscosity, water content, total organic carbon, and appearance and extraction performance including efficiency, selectivity and reusability of the designed solvents were thoroughly analyzed and compared. Second, the most suitable cation to form MILs for the removal of iron and the best HDES for the extraction of titanium were defined based on sustainable chemistry metrics. The purity of the obtained titanium solution could reach 99.87% after the combined use of the selected MIL and HDES. Finally, toxicity studies on the reagents applied were performed and compared with existing methods. [ABSTRACT FROM AUTHOR]

Current catalytic hydrogenolysis of lignin C–O bonds, which is crucial for lignin valorization, often requires a noble metal catalyst or/and harsh conditions such as elevated temperatures and high pressures. Herein, we report a highly selective electrochemical protocol to reductively cleave the benzylic C–O bond of the α-O-4 lignin model compound benzyl phenyl ether (BPE) at room temperature and ambient pressure. Nearly complete conversion of BPE to toluene and phenol in methanol was achieved in an undivided cell using Ni foam at both the anode and cathode, with yields of 97% and 30%, respectively. Using a divided cell, yields of 90% (toluene) and 84% (phenol) could be achieved using inexpensive carbon paper as the cathode when Ni(II) salts were added to the cathode chamber. Notably, other divalent metal salts did not lead to any product formation, suggesting a unique role of Ni ions in benzylic C–O bond cleavage. Further, a substrate scope study revealed the suitability of the method for a variety of substituted BPEs. This work provides an economical and environmentally friendly method for selective cleavage of C–O bonds in benzylic ethers as model compounds for lignin. [ABSTRACT FROM AUTHOR]

With the increasing use and the consequent retirement of lithium-ion batteries (LIBs), there has been an upsurge in spent LIBs, posing significant challenges to energy, resources, and the environment, which has led to the necessity to recycle spent LIBs. For the recovery of valuable components in cathode materials, traditional hydrometallurgical and pyrometallurgical methods are not conducive to the sustainable development of the environment, making it crucial to explore lithium-ion battery (LIB) recovery technologies beyond traditional methods. This paper focuses on introducing intensification technologies that are beyond the traditional methods, including external field intensification technologies (in the fields of acoustics, optics, electricity, and magnetism), novel solvent-based intensification technologies, direct recovery technologies, and potential development technologies. From the perspective of process intensification, the process flow, principle, effect, and scope of application of various recovery technologies are systematically summarized. Furthermore, the advantages of these advanced recovery methods and the current challenges faced by them are discussed to propose the potential research direction of the recovery technology of lithium-ion battery cathode materials, which is of significant importance for the sustainable development of the global new energy industry, the maintenance of ecological balance, and the circular utilization of mineral resources, such as lithium, nickel, and cobalt. [ABSTRACT FROM AUTHOR]

Chemical catalytic conversion of biomass-derived sugars to lactic acid has attracted considerable attention due to the cheap, abundant and renewable nature of biomass and its huge potential application in the synthesis of biocompatible and biodegradable polylactic acid resins. However, this route is still a huge challenge in view of the transformation efficiency. This paper reports a series of Zn-based catalysts, which are facile and cheap to prepare and highly efficient for the conversion of biomass-derived carbohydrates to ethyl lactate (EL). The microstructure, active site composition and surface properties were characterized by TEM, HRTEM, XRD, NH3-TPD, CO2-TPD, Py-IR, and XPS. The catalytic performance of catalysts in the conversion of biomass-derived carbohydrates to ethyl lactate (EL) and the effect of water content were investigated. It was found that the Zn species played a decisive role in regulating the strengths of the acidic and basic sites to match the rate of each reaction in the tandem reactions. The basic sites are beneficial for isomerization and retro-aldol condensation, while the temperature-responsive released H+ protons are responsible for the dehydration of triose to methylglyoxal, a rate-determining step in the conversion of triose to EL. Addition of a small amount of water could enhance the release of the protons and thus accelerate the dehydration reaction, but excessive water would favor the formation of humins. Using ZnSi-2 as a catalyst under optimal conditions, yields as high as 74.5% of EL from glucose, 81.0% from fructose, 70.9% from mannose, and 80.3% from sucrose could be achieved with tens of times higher productivity than the previously reported values in the literature. DFT calculations revealed that Zn(OEt)Cl, Zn(OH)Cl, and Zn(OH)(OEt) were probably the active components. In addition, the stability of the catalyst as well as the deactivation and regeneration was also studied. The findings in this research provide new insights into the exploration of efficient catalysts for biomass conversion to value-added chemicals. [ABSTRACT FROM AUTHOR]

For much of the Caribbean region, plastic pollution and the persistence of the great Atlantic Sargassum belt lead to significant regional loss in biodiversity, employment and tourism. Yet, seaweeds such as Sargassum possess all the characteristics for bioplastic production. This study presents a new process on the production of biodegradable calcium alginate (Ca(Alg)2) composite bioplastic, and evaluates its economic feasibility and environmental impact in the Caribbean, compared to bio-based polylactic acid (PLA) and synthetic plastics (PET). Our cradle-to-gate life cycle impact assessment (LCIA) shows normalized (kg CO2eq per kg plastic) greenhouse gas (GHG) impacts 3 to 7 times higher for the baseline alginate composite process over those of PLA and PET films – linked mainly to chemical consumption. However, through the integration of abundant bioenergy from the local paper industry and the nascent E-methanol (E-MeOH) supply chains, GHG impact reduces by 79% – illustrating a pathway to a sustainable bioplastic production flowsheet. More attractively, the alginate bioplastic outperforms in providing ultra-low oxygen barrier packaging properties – with a required mass of plastic material producing a total carbon footprint (kg CO2eq) 64–978 times lower than PLA and PET respectively, and overall packaging costs 280 times less than current synthetic plastic. Techno-economics illustrate that a total annualized cost (TAC) for alginate bioplastic of $US 4.56 per kg is possible, ensuring high economic feasibility, comparable to current commercial bio-based alternatives. Moreover, sensitivity analysis highlights that variability in TAC was mainly associated with sodium alginate utilization in the manufacture process – contributing up to 67% to the overall cost. In light of this, the integration of sound policies aligned to improved consumer awareness and reduced plastic waste can help to drive greater economic feasibility of the alginate bioplastic industry. Ultimately, our study illustrates a viable and sustainable alginate bioplastic alternative, promoting and informing on packaging innovation while achieving low carbon operations within the Caribbean plastic sector. [ABSTRACT FROM AUTHOR]

As a kind of super stable thermoset resin, phenolic epoxy vinyl ester resin (PEVER) is widely applied as a solvent and corrosion resistant material. However, its highly cross-linked three-dimensional network challenges its degradation and recycling. In this study, we report an efficient catalytic system of KOH/C2H5OH–H2O to degrade PEVER under a mild reaction condition of 160 °C. It is discovered that the efficiency of KOH for degrading PEVER resulted from the high affinity of K+ to PEVER. Besides the resin, K+ shows good affinity to other organic substances, such as ethyl acetate, toluene, and petroleum ether, and it surpassed largely Na+ (NaOH) in the affinity to organic substances. The NMR and FT-IR characterizations indicated the degradation of PEVER via the hydrolysis of ester bonds, by which high value-added copolymer of styrene and methacrylic acid (SMAA), potassium salt of SMAA (SMAA-K), and novolac glycidyl ether (NOGE) were obtained. SMAA-K can be used as an interface modifier owing to its surface activity. The modified filter paper prepared by SMAA has high hydrophobicity. NOGE can be recycled to prepare a new polyurethane material. This study provides a new strategy for the chemical degradation and recycling of thermoset PEVER waste. [ABSTRACT FROM AUTHOR]

In this paper, a set of copper-based ternary deep eutectic solvents (Cu-DESs) is synthesized and applied in Glaser-type homo- and cross-coupling of terminal alkynes. These reactions occur under exogenous-ligand-free, base-free, and additive-free conditions and provide satisfactory to excellent yields (up to 99%) under mild conditions. The Cu-DESs can be recycled eight times and the only by-product is water, which fully accords with the principles of green chemistry. [ABSTRACT FROM AUTHOR]

Single-electron reduction of a carbonyl by photoredox catalysis enables the generation of ketyl radicals, providing a benign procedure for constructing C–C bonds. However, external photocatalysts are required. In this paper, photoinduced generation of ketyl radicals and application in C–C coupling are reported, which require no use of any external photocatalyst. Irradiation of carbonyl with purple light in the presence of a tertiary amine generates highly reactive ketyl radicals, enabling a series of important reactions in synthetic chemistry, such as the reductive coupling of aldehydes, ketones, and imines, the allylation of aldehydes, the Barbier reaction, reductive arylation, and aldehyde–aniline coupling. We also present evidence to support the ketyl radicals being formed via photoinduced intermolecular electron transfer from the tertiary amine to aryl aldehydes. [ABSTRACT FROM AUTHOR]

The simultaneous production of hydrogen and biomass-based chemicals from biomass-derived feedstock aqueous solutions via photocatalysis is appealing because no additional sacrificial agent is needed. However, limited success has been achieved. This paper reports efficient nori-shaped carbon nitride-based photocatalysts with potassium/oxygen co-doping and cyano group introduction for efficient conversion of biomass-derived monosaccharides to produce lactic acid and hydrogen simultaneously. The obtained photocatalyst has an adjustable bandgap, fast migration/separation rate of photo-generated carriers and displays excellent photocatalytic performance with respect to xylose conversion (∼95.0%), lactic acid selectivity (90.5%) and hydrogen generation (∼33 380 μmol g−1 h−1) in the presence of visible light. The h+, ˙OH, ˙O2− and 1O2 drive xylose conversion and lactic acid production. For biomass-derived pentoses and hexoses, the reaction system also exhibits excellent photocatalytic activity of lactic acid selectivity and hydrogen generation; the reported photocatalyst has excellent reusability. This paper provides a new perspective for hydrogen generation and biorefineries via a photocatalyst. [ABSTRACT FROM AUTHOR]

Eucalyptus dissolving kraft pulp pre-hydrolysis liquor (PHL) is rich in sugar and other biomass resources, which can produce furfural and may serve as a platform molecule for sustainable fuel production. However, the presence of lignin increases the side reactions during the high-value utilization of PHL. Therefore, a novel process technology, consisting of laccase-induced lignin polymerization, was developed in this paper to enhance the removal of lignin. During the study, the mechanism of the action of laccase on lignin was speculated and it was discovered that the effect of laccase on lignin is to polymerize its small molecules. The main reaction of laccase oxidation is the formation of 5-5′ and 4-O-5′ bonds, and occasionally β-O-4′. If position 5 is blocked, other side reactions will occur, including coupling at position 1 and oxidation at position α. Simultaneously, the –OH content of lignin increases under the activation of laccase. Then, the conversion of furfural from the delignified pre-hydrolysis liquor (LPHL) under the catalysis of 2 wt% sulfuric acid was investigated. With the traditional one-pot reactor system, furfural and the reaction medium cannot be separated in time and the degradation of furfural cannot be prevented. The side reactions caused by this, such as fragmentation, condensation and resinification, which is visible to the naked eye, involve the production of humic substances, which becomes the most important factor in the low furfural yield. These side reactions are verified by GC/MS. According to the results in this study, the biorefinery process towards PHL, which allows the separation of lignin by laccase and the conversion of xylose to furfural, improves the overall application of the PHL biomass. [ABSTRACT FROM AUTHOR]

For a knowledge-based design of enzyme catalysis in deep eutectic solvents (DESs), the influence of the DES properties (e.g., water activity and viscosity) and the impact of DESs and their individual components must be assessed. This paper investigates three different DESs: choline chloride–glycerol (ChCl–Gly), choline chloride–ethylene glycol (ChCl–EG), and ethyl ammonium chloride–glycerol (EACl–Gly). The specific activity and half-life time of horse liver alcohol dehydrogenase (HLADH) were experimentally determined in these DESs with water contents ranging from 0%–100%. HLADH showed limited activity in neat DESs, which was enhanced by adding water. Experiments with individual DES components of ChCl–Gly were carried out to clarify their individual influence. Glycerol acts as a strong stabilizer for the enzyme, whereas choline chloride's results are deleterious. To understand the experimental findings, molecular dynamics (MD) simulations were carried out to quantify the solvation layer and calculate the spatial distribution of the solvent molecules around HLADH. The experimental and the in silico approach suggests that designing novel DESs with higher glycerol loadings would result in improved media for biocatalysis. This is demonstrated by performing the reduction of cinnamaldehyde to cinnamyl alcohol—a relevant compound for the food industry and cosmetics—in ChCl–Gly (1 : 9 molar ratio), with 20 vol% water to decrease the viscosity. HLADH is highly active and stable under these new conditions, giving promising productivity (15.3 g L−1 d−1). This paper demonstrates that DESs can be designed to be both substrate-solubilizers and enzyme-compatible, opening new research lines for green chemistry and biocatalysis. [ABSTRACT FROM AUTHOR]

The electrochemical ring hydrogenation of aromatic compounds is an important synthetic tool, though scarcely described in the literature. This research paper investigates the utilization of different Pd- and Pt-containing electrocatalyst materials for an electrosynthesis of tetrahydrofuran derivatives from furfural and related furans. It focuses on the selectivity of the ring hydrogenation as a function of the electrocatalyst composition, as well as on a preliminary elucidation of the electrocatalytic activity during repetitive electrode use. Furthermore, different furanic derivatives are employed as starting material for mechanistic considerations. While furfural, furfuryl alcohol and furan are found to be highly reactive in ring hydrogenation reactions, furoic acid and 2-methyl furan do not show this behavior. Selectivities for tetrahydrofurfuryl alcohol of up to 15.3% (from furfural) and 33% (from furfuryl alcohol) are observed in this context. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl groups containing bicyclo[1.1.1]pentanes (BCPs) are gaining increasing interest in the pharmaceutical industry and materials science; however, the development of an efficient methodology to construct perfluoroalkylated BCPs remains a challenging task. In this paper, we present a metal-free strategy to synthesize 1-perfluoroalkyl-3-heteroaryl bicyclo[1.1.1]pentanes using an electron donor-acceptor (EDA) complex for the perfluoroalkylation of [1.1.1]propellane. After visible light irradiation, the resulting EDA complexes formed by perfluoroalkyl iodide and DBU lead to the generation of perfluoroalkyl radicals. These then sequentially react with highly strained [1.1.1]propellane and various heterocyclic compounds. Mechanistic studies revealed that this method proceeded via a radical chain reaction. This strategy may provide a versatile and sustainable way to obtain 1-perfluoroalkyl-3-heteroaryl bicyclo[1.1.1]pentanes with good functional group tolerance under mild conditions. [ABSTRACT FROM AUTHOR]

Nowadays, afterglow materials with long-lifetime phosphorescence are mainly prepared from metal-containing substances. It is necessary and challenging to find a simple, green and feasible approach to generate afterglow materials with excellent phosphorescence from biomass materials. Herein, a facile strategy is proposed to construct afterglow materials via confining fluorescence carbon dots from lignin into silica (SiO2). Specifically, a microwave-assisted carboxymethylation process was adopted for the lignin precursor, which endowed the lignin with abundant carboxyl groups (3.69 mmol g−1) and maintained its benzene ring structure. Subsequently, N-doped lignin-based carbon dots (NL-CDs) with nanoscale size (6.07 nm) and excellent fluorescence (quantum yield = 30.6%) were prepared through the hydrothermal treatment of carboxymethylated lignin. Finally, the NL-CDs were confined in SiO2 and the generated NL-CDs@SiO2 exhibited excellent phosphorescence behavior in both solid-state and aqueous solution. The obtained afterglow materials achieved 5.97% of phosphorescence quantum yield and 834 ms of lifetime, which could be observed for 6 s by the naked eye. Meanwhile, a multi-modal information encryption strategy was designed based on the phosphorescence characteristics of the afterglow materials. The proposed strategy in this paper will pave the way to generate afterglow materials from lignin biomass and provide guidance for high-value utilization of lignin. [ABSTRACT FROM AUTHOR]

During the preparation of a LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode material by a hydroxide coprecipitation method, the use of ammonia water (complexing agent) is likely to cause ammonia pollution environmental problems. In this paper, citric acid is used as the complexing agent to replace ammonia water to carry out research on the green preparation of the NCM622 cathode material. The obtained samples were characterized and analyzed by X-ray diffraction, scanning electron microscopy, Raman spectroscopy, particle size distribution and the corresponding electrochemical performance tests. The research results show that the prepared NCM622 precursor has a spherical secondary particle structure, in which the primary particles are tightly bound and the surface of the particles is smooth. After calcination at 800 °C for 12 h, the obtained NCM622 electrode material has the maximum content of spherical secondary particles and a complete layered structure. It also has a low cation mixing degree and high discharge specific capacity and good cycle performance and rate performance. The NCM622 sample has an initial discharge specific capacity of 208.6 mA h g−1 at 0.1C and its capacity retention rate after 100 cycles at 0.5C is as high as 98.0%. All these show that the use of citric acid instead of ammonia water as the complexing agent to prepare the NCM622 electrode material via the hydroxide coprecipitation method is a good strategy, which is not only environmentally friendly, but also can prepare the NCM622 cathode material with better electrochemical performance, showing broad application prospects. [ABSTRACT FROM AUTHOR]

Intense efforts are currently being devoted to discovering cost-effective catalysts for the selective reduction of carbon dioxide (CO2). Many advances have indeed been achieved in the design of molecular complexes containing second coordination chemical functionalities that have contributed to boosting the homogeneous electrocatalytic activity. The introduction of such chemical facets in heterogeneous catalysis is still lacking. Here, we report the electrocatalytic properties of a chemically modified electrode with a molecular iron-porphyrin catalyst holding urea functions (UrFe) in CO2 reduction, acting as a multipoint hydrogen bonding cleft to enhance CO2 binding. The immobilization of UrFe on multiwall carbon nanotubes (MWCNTs)/carbon paper (CP) allows the investigation of the catalytic performance in water. We found, herein, that the modified electrode displays excellent selectivity towards CO production in water, which is also acting as the sole proton source. Importantly, we observed one of the highest effective turnover frequency (eTOF) values (>21 s−1) at a potential of −0.78 V vs. RHE in comparison with similar modified electrode containing bare iron-porphyrin analogues. Our results therefore point to a remarkable gain in electrocatalytic performance of molecular catalysts at the surface of the electrodes with the added dimensionality of chemical functions operating as molecular clefts towards the binding and reduction of CO2. [ABSTRACT FROM AUTHOR]

The production of ammonia under ambient conditions has been a long-standing challenge for the chemical industry. The electroreduction of nitrate presents a promising solution for nitrate wastewater treatment and decentralized ammonia production. However, traditional Ag-based catalysts suffer from nitrate-to-nitrite conversion, leading to toxicity concerns and hampering ammonia preparation. In this study, we synthesized an innovative Ag–Cu–P catalyst that effectively tunes the d-band centre and electronic structure. The catalyst exhibited a remarkable NH4+ yield rate of 566.30 μmol cm−2 h−1 at −0.3 V (vs. RHE), reducing nitrite content to below the drinking water standard. Characterization results revealed a distinctive fern leaf-like morphology, providing an expanded active surface area. The challenge of facile nitrate conversion to nitrite on Ag-based catalysts has been addressed through the implementation of electronic structure modulation in this work. Theoretical calculations confirmed the substantial reduction in the energy barrier by modulating the d-band centre and electronic structure, facilitating the conversion of nitrite to ammonia. The regulation and analysis of d-band centres yielded valuable insights for catalyst material design. Meanwhile, direct evidence for potential intermediates has also been presented through in situ spectroscopy. These findings hold significant potential for practical applications, such as enhanced wastewater treatment and decentralized ammonia production, and provide support in the pressing need for sustainable ammonia synthesis under ambient conditions. [ABSTRACT FROM AUTHOR]

The food industry produces a large amount of food byproducts that, when appropriately valorized, can become a renewable source of sustainable materials. The valorization of these byproducts requires a new set of green technologies. For example, fish farming, one of the fastest growing sectors, uses only 30% to 40% of the fish as food, with the remaining 60% to 70% being a byproduct. One example of valorization of fish byproducts is the upcycling of fish skin into leather. This new fish leather has interesting properties, in part due to its microstructure, but also has new shortcomings like the high hydrophilicity and water absorption. To mitigate these issues, a water protecting coating was developed using only two other food byproducts: epoxidized soybean oil and the fatty acid trimer Pripol. These two building blocks were deposited on leather and then crosslinked to create a strong network that made leather hydrophobic, with a water contact angle >120° without the need for fluorine or silicone chemistry or the use of nanoparticles. The coating was applied via dip-coating and was cured at low temperature as required by fish leather without the need for initiators, catalysts, which are mostly toxic, or UV light. The same strategy could also be applied to cotton, showing that its application is not limited only to leather. The coating showed good adhesion to the substrate and excellent water resistance, making the leather and the cotton hydrophobic and substantially reducing the water absorption, without changing the breathability, flexibility and microstructure of the substrate. This work demonstrates how high performing materials can be created within a green chemistry and circular economy framework, with results that can be relevant for other textile materials, contributing to the effort for developing sustainable alternatives for providing hydrophobicity. [ABSTRACT FROM AUTHOR]

The predominant adhesives currently utilized in the wood sector are sourced from petroleum. However, it is crucial to acknowledge that fossil resources possess a limited supply, and their extraction procedures can lead to adverse effects on the ecosystem. Renewable biomass resources have important application prospects in wood adhesives. This paper reviews the recent research progress on utilizing biomass to replace or modify conventional petroleum-based adhesives, focusing on the application of tannin, lignin, protein, starch, and cellulose in urea–formaldehyde (UF), melamine, phenol–formaldehyde (PF), epoxy (EP), and polyurethane (PU) resin adhesives. The symbiosis of renewable biomass with conventional petroleum-based adhesives portends substantial advancements for the wood adhesive industry. This review evaluates the substitution capacity and modification effect of biomass, discusses its application prospects in the wood-based panel industry, and predicts the future direction of biomass in wood adhesives, providing new inspirations for the development of novel green adhesives. [ABSTRACT FROM AUTHOR]

In view of the growing demand for synthetic molecules or materials by researchers from both the core sciences and interdisciplinary sectors, the field of organic synthesis needs to be strategically more powerful to produce more molecules in a shorter time. Ensuring a reduction in the use of solvents, catalysts, reagents, time, effort, and waste is essential during green chemical syntheses. Keeping those criteria in mind, the integration of chemical reactions is very much needed. Integrated organic synthesis can be considered the ideal replacement for stepwise synthesis to fulfill demand while maintaining green parameters. The electrochemical cascade process satisfies the essential criteria of greener integrated synthesis to a great extent, providing a modern strategic tool in the arsenal of synthetic chemists. The strategy is applied extensively by researchers, as evidenced by the growing number of publications, amounting to more than a hundred papers on the development of synthesis methods using electrochemical cascade reactions. A thorough understanding of the process is needed to implement the strategy further in targeted synthesis and methodology development for cutting-edge research. To grow the concept among researchers, a concise account of published articles on the topic, depicting the mechanisms, prospects, and problems of the developed methods, is highly desirable. Quenching the thirst herein, we present a concise review of electrochemical cascade processes reported in the literature since 2015. The precedent reactions developed earlier are also discussed in this context. Electrochemical multicomponent reactions involving the cascade process are also covered, expanding the scope of the review. The sections are classified based on the types of functionalization. The mechanistic details of each category of reactions are thoroughly covered to present a clear idea of the redox behavior of different reagents under electrochemical conditions. The prospects and problems associated with the methods are also discussed. [ABSTRACT FROM AUTHOR]

As a versatile and environmentally friendly chemical, hydrogen peroxide (H2O2) is in high demand. The current anthraquinone oxidation process suffers from high energy consumption in hydrogen production and the cumbersome alternating operations of hydrogenation and oxidation. The direct synthesis of H2O2 from H2 and O2 is constrained by the balance between safety and efficiency and heavy metal pollution from catalysts. Two-electron oxygen reduction reaction (2e− ORR) is an efficient, safe, and low-cost route for the production of H2O2. This 2e− ORR pathway has potential to become a supplement to the anthraquinone process because of fossil energy-free feature. The bottleneck of the industrialization of 2e− ORR is the lack of efficient catalysts. The 2e− ORR catalytic performance of noble metal electrode materials urgently needs to be significantly enhanced by smart design. However, the high price and limited reserves of these noble metal-based materials still severely limit their commercialization. Among many 2e− ORR catalysts, carbon-based catalysts have received much attention because of their low cost and diverse structures. This study reviews the research progress and the synthesis methods of carbon-based catalysts for 2e− ORR in recent years. First, this paper introduces the fundamental mechanism of H2O2 production by 2e− ORR through a combination of theory and experiment. Then, the synthesis methods and optimization strategies of various high-efficiency carbon-based catalysts are discussed. Finally, the various influencing factors (pH effect, pore structure, and carbon defects) and the practical applications for H2O2 production are analyzed. In addition, the future research direction is also proposed to promote the development of carbon-based catalysts for 2e− ORR toward industrialization. Although carbon-based catalysts display obvious advantages for electrocatalytic applications, there are still a few shortcomings that need to be overcome. The intrinsic activity and the long-term stability of carbon-based materials still require to be improved to a level that can be compared with those of noble metal-based catalysts. This review presents a comprehensive overview of the latest developments in the production of H2O2 by 2e− ORR on carbon-based catalysts, combining the most advanced theoretical and experimental literature available. The current state of the research on carbon-based catalysts in recent years indicates great promise for further advancement. [ABSTRACT FROM AUTHOR]

The document is a table of contents for the journal "Green Chemistry," which focuses on cutting-edge research in the chemical industry to reduce environmental impact. The journal covers topics such as vinyl polymer degradation, bioenergy sources, carbon anodes for lithium-ion batteries, and lignin biorefinery. Published by The Royal Society of Chemistry, the journal aims to promote sustainable and environmentally friendly chemistry through articles on catalysis, organic compound synthesis, bioconversion, materials science, and environmental chemistry. The journal is available electronically. [Extracted from the article]

Due to the severe waste plastics pollution issues, fabricating biodegradable films as substitutes for plastic has been a pursuit of modern scientists for the past few years. UV (ultraviolet) shielding is essential for the application of biodegradable films in packaging materials, agricultural mulch, plastic greenhouses, and window films. Identified as a natural UV-absorber, lignin can be a safe additive to biodegradable film, endowing the film with urgently needed UV-resistance properties while ensuring the overall sustainability of the films. The present paper comprehensively reviews the research status on the preparation and application of lignin-containing biodegradable UV-blocking films. Additionally, the effect of lignin on the mechanical and optical properties of films is revealed. In general, this review provides some theoretical guidance for manufacturing lignin-containing biodegradable UV-blocking films with outstanding mechanical properties and optical transmittance, thus broadening their application in packaging, agriculture, and green building materials. [ABSTRACT FROM AUTHOR]

The document is a contents list for the journal "Green Chemistry," which focuses on cutting-edge research aimed at reducing the environmental impact of the chemical industry. The journal covers various topics such as the utilization of methanol as a C1 source, deep eutectic solvents for CO2 capture and utilization, and advancements in catalysts for glycerol oxidation. Published by The Royal Society of Chemistry, the journal is available electronically and provides valuable insights and advancements in green chemistry and sustainable practices. It may be of interest to researchers and individuals interested in sustainable chemistry. [Extracted from the article]

In this paper, we describe an approach for producing both high quality and high quantity of lignin through studying the structural change of lignin during treatment of poplar wood in γ-valerolactone (GVL) for a range of temperatures (from 80 to 120 °C) and reaction time at temperature (from 1 to 24 h). Various techniques, including nuclear magnetic resonance (NMR) spectroscopies (solution- and gel-state 1H–13C 2D HSQC and 31P) and gel-permeation chromatography (GPC) were applied to characterize the lignin structures. As the GVL-extracted lignin yield increases, the level of β-ether units decreases and the level of condensation products increases. The β-ether content, the aliphatic hydroxyl group content, and the molecular weight of the GVL-extracted lignin fractions were close to the poplar lignin from other preparation methods (e.g., enzyme lignin). A two-step hydrolytic process (120 °C, 2 × 15 min) gave a higher lignin yield (56.5% vs. 54.8%) with three times higher β-ether content (31.9% vs. 10.6%) than lignin extracted from a single-step process at 120 °C for 1 h. The results demonstrate that multiple-step cycling of cosolvent-assisted hydrolysis can help preserve more of the virgin ether-bond structures of GVL-extracted poplar lignin. Such a strategy can also be applied to a fully continuous-flow reactor system in future research to further improve both the productivity and quality of GVL-extracted lignin. [ABSTRACT FROM AUTHOR]

Glycerol, which bears green, low-cost, and good miscibility features, provides a variety of solvent portfolios to satisfy the complex market demands. Owing to its abundant feedstock and unique properties, glycerol is a good candidate in catalysis, high-value-added chemical conversion, and solvents. It can also be used as an energy transportation medium attributed to its high boiling temperature, promising thermal stability, and fertile hydrogen bond. Despite the great potential of glycerol in energy transportation, a review paper that summarizes and discusses its recent advances is blank to date. In this review paper, recent advances in the utilization of glycerol and glycerol-based mixture solvent systems in energy transportation were summarized. Thermophysical properties of glycerol-containing fluids, including their performance in various heat transfer occasions, and principles of related energy transportation were comprehensively introduced and discussed. Applications of these fluids in industrial processes were also discussed systematically. Furthermore, advantages and drawbacks of glycerol in energy transportation were concluded. It opens an important avenue to alleviate the backlog of glycerol production by means of valuable applications. [ABSTRACT FROM AUTHOR]

Biocatalysis will play a central role in future chemical conversions, aiming at more sustainable strategies while keeping efficiency and economics. The mere use of enzymes does not ensure the greenness of a process, and quantitative environmental metrics must substantiate this. Simple but meaningful approaches are needed, particularly when reactions are still at a preliminary phase of research. This paper explores the use of the E-factor and a gate-to-gate strategy to assess environmental metrics for biocatalysis at the proof-of-concept stage. The upstream part – the actual biocatalytic reaction – and the downstream part – the purification of the product – are considered, providing the complete E-factor of the synthesis. As a case study, the hydration of oleic acid catalyzed by oleate hydratases (OHY) is used. Depending on the reaction conditions (particularly the substrate loadings), and the chosen downstream, total E-factors range from 15–20 to 160, mostly comprising wastewater (from the reaction media) and solvent (from the downstream part). The evaluation is completed with the estimation of the Total Carbon Dioxide Release (TCR), kg of CO2 per kg of product, which provides comparable data to benchmark synthetic strategies. The timely identification of hot spots (large contributors to the environmental impact) enables researchers and practitioners to propose experiments to show that biocatalysis can be performed under more sustainable conditions. [ABSTRACT FROM AUTHOR]

GreenChemistry Cutting- edge research for a greener sustainable future rsc. li/ greenchem ISSN 1463- 9262 Volume 26 Number 16 21 August 2024 Pages 8883- 9272 PAPER Xiujuan Li et al. Harnessing solvation- guided engineering to enhance deep eutectic solvent resistance and thermostability in enzymes [Extracted from the article]

GreenChemistry Cutting- edge research for a greener sustainable future rsc. li/ greenchem Volume 26 Number 16 21 August 2024 Pages 8883- 9272 ISSN 1463- 9262 PAPER Sara Iborra, Avelino Corma et al. Chemoenzymatic synthesis of amino- esters as precursors of ammonium salt- based surfactants from 5- hydroxymethylfurfural ( HMF) [Extracted from the article]

GreenChemistry Cutting- edge research for a greener sustainable future rsc. li/ greenchem Volume 26 Number 15 7 August 2024 Pages 8433- 8882 ISSN 1463- 9262 PAPER George W. Huber et al. Aliphatic amines from waste polyolefi ns by tandem pyrolysis, hydroformylation, and reductive amination [Extracted from the article]

GreenChemistry Cutting- edge research for a greener sustainable future rsc. li/ greenchem ISSN 1463- 9262 Volume 26 Number 15 7 August 2024 Pages 8433- 8882 PAPER André Bardow et al. Early- stage impact assessment tool ( ESTIMATe) for the life cycle assessment of CO 2 - based chemicals [Extracted from the article]

Global production of synthetic polyamides (PA), or nylons, is increasing while recycling rates are currently below 5% contributing to the global plastics crisis. Enzymatic depolymerization is a powerful strategy to overcome the drawbacks of mechanical and chemical recycling and has the potential to increase PA recycling rates. However, enzymatic depolymerization of PA is currently limited to a small group of nylonases (NylC) that exhibit low activities making them unsuitable for efficient enzymatic recycling. In this study, we extend the diversity of nylonases, namely NylC1, NylC2, and NylC3 by library screenings and in silico analysis. Three novel nylonases were identified that showed varying sequence identities ranging from 84 to 32% compared to the previously characterized NylCp2 from Paenarthrobacter ureafaciens. Activity of these nylonase candidates towards cyclic PA-oligomers was confirmed via the detection of soluble degradation products. These nylonases were also active on synthesized poly(ester amides) (PEA), and this activity was synergistically increased by combination with the leaf and branch compost cutinase LCC resulting in the hydrolysis of approximately 1% of the total polymer. Overall, our discoveries greatly increase the sequence space of NylC enzymes for future enzyme engineering strategies to boost their activities, and they show the potential of PEA for tuning the biodegradability of performance polymers. Thereby, this study leads the path for developing efficient enzymatic PA and PEA depolymerization processes, revealing significant insights into combining the contrary parameters of performance and biodegradability of polymers. [ABSTRACT FROM AUTHOR]

The catalytic pyrolysis of guaiacol-based lignin monomers, vanillin, syringol, and eugenol over commercial HZSM-5 has been investigated using operando Photoelectron Photoion Coincidence (PEPICO) spectroscopy to unveil the reaction mechanism by detecting reactive intermediates, such as quinone methides and ketenes, and products. Vanillin shares the decomposition mechanism with guaiacol due to prompt and efficient decarbonylation, which allows us to control this reaction leading to a phenol selectivity increase by switching to a faujasite catalyst and decreasing the Si/Al ratio. Syringol first demethylates to 3-methoxycatechol, which mainly dehydroxylates to o- and m-guaiacol. Ketene formation channels over HZSM-5 are less important here than for guaiacol or vanillin, but product distribution remains similar. C3 addition to guaiacol yields eugenol, which shows a more complex product distribution upon catalytic pyrolysis. By analogies to monomers with simplified functionalization, namely allylbenzene, 4-allylcatechol, and 4-methylcatechol, the eugenol chemistry could be fully resolved. Previously postulated reactive semi-quinone intermediates are detected spectroscopically, and their involvement opens alternative pathways to condensation and phenol formation. Allyl groups, produced by dehydroxylation of the β-O-4 bond, may not only decompose via C1/C2/C3 loss, but also cyclize to indene and its derivatives over HZSM-5. This comparably high reactivity leads to an unselective branching of the chemistry and to a complex product distribution, which is difficult to control. Indenes and naphthalenes are also prototypical coke precursors efficiently deactivating the catalyst. We rely on these mechanistic insights to discuss strategies to fine-tune process conditions to increase the selectivities of desired products by enhancing either vanillin and guaiacol or supressing eugenol yields from native lignin. [ABSTRACT FROM AUTHOR]

The electroconversion of carbon dioxide (CO2) into value-added chemicals has attracted widespread attention worldwide. Exploring efficient catalysts and designing reasonable reactants have become popular research directions in the strategy of coupling anode and cathode reactions. Herein, we report the construction of a self-supporting bifunctional Sn-SnSx electrode using a one-step electrodeposition method. The valence states of Sn at the Sn-SnSx surface are Sn4+, Sn2+ and Sn0, and the electrode exhibits excellent performances for the carbon dioxide reduction reaction (CO2RR) and glucose oxidation reaction (GOR), respectively. For the CO2RR, the Sn-SnSx electrode produced formate with a faradaic efficiency (FE) of 93.3% and a stability of 36 h. Meanwhile, tin sulfides were first applied in anodic oxidation and a high FE of 88% was achieved for formate production in the GOR. Impressively, Sn-SnSx as a bifunctional electrode achieved co-production of formate at both the anode and cathode in the integrated electrolyzer coupled with the CO2RR and GOR. This coupling process combines the technical means of "electrooxidation-electroreduction" with the choice of reactants "CO2-C6H12O6", resulting in FE values of 93.9% and 87.4% at the cathode and anode for the production of formate, as well as a 58.3% electrical energy saving for formate production in comparison with the traditional CO2RR coupled with the water oxidation reaction. [ABSTRACT FROM AUTHOR]

Silicon (Si) materials have attracted growing attention in lithium-ion batteries (LIBs) due to their remarkably high-theoretical capacity and abundance on Earth. Despite the excellent edges, the widespread application of silicon materials in LIBs has been severely limited by rapid capacity decay and an unstable solidelectrolyte interphase (SEI) due to their substantial volume changes (>300%). Here, we report a novel water-soluble binder (CW-20), comprising sodium carboxymethyl cellulose (CMC-Na) and waterborne polyurethane (WPU). Not only the novel binder can establish a cross-linked three-dimensional (3D) network through hydrogen bonding, which effectively maintains the electrodes' integrity, but also the binder can form a stable SEI layer, thereby improving the cycling stability and durability. Thus, the Si@CW-20 electrode maintains a specific capacity of 2626.2 mA h g-1 after 100 cycles at 0.1C. After 500 cycles at 0.5C, the Si@CW-20 electrode exhibits excellent stability, maintaining a high specific capacity of 1450.7 mA h g-1 with a capacity decline rate of 0.08% per cycle. Moreover, Si/C@CW-20 exhibits a capacity retention rate of 86.93% after 250 cycles at 1C. The cycling stability and durability of Si and Si/C anodes demonstrate significant potential for this strategy in facilitating the widespread implementation of high-capacity LIBs. [ABSTRACT FROM AUTHOR]

Electrocatalytic nitrate reduction reaction (NO3RR) coupled with organic compounds to synthesize oximes for value-added conversion of waste pollutants has very promising prospects. However, due to the susceptibility of the feedstock to hydrogenation, the relatively low reaction efficiency, and the poor stability of oximes, the reaction in acidic electrolytes remains a formidable challenge. Herein, we report a novel strategy for the one-step synthesis of oximes from nitrite and aldehydes/ketones in acidic electrolytes using a Zn-based catalyst (multilayered Zn nanosheet catalyst, M-ZnNSs). 99% yield and 99% selectivity of phenylacetaldehyde oxime were achieved at a constant current of -12 mA cm-2. Moreover, various aldehydes/ketones were efficiently converted to oximes with yield and selectivity up to >90%, demonstrating the high versatility of this method. Furthermore, the catalyst exhibited remarkable long-term stability (>100 h). This work proposes a green strategy to promote the recycling of nitrogen resources, enhance the value of NO3- conversion products, and develop new ideas for electrochemical C-N coupling. [ABSTRACT FROM AUTHOR]

The γ C-H amination of carboxylic acid presents a promising and sustainable strategy for synthesizing high-value pharmaceutical chemicals. Radical reaction pathways initiated by aroyloxy radical-involved hydrogen atom transfer (HAT) provide diverse but challenging opportunities for remote C-H functionalization. In this report, the first example of intramolecular γ C-H amination of carboxylic acids using a commercially available oxime auxiliary has been achieved. This innovative approach employs a radical relay chaperone, facilitating selective C-H functionalization via 1,5-HAT/radical cross-coupling and enabling the net incorporation of ammonia at the γ carbon of carboxylic acids. In addition, this protocol enables the recycling of the by-product benzophenone, and both product isolation and by-product recycling are silica gel-free. The reactions offer high chemo- and regio-selectivities, operate under mild reaction conditions, boast a broad substrate scope, exhibit good functional group compatibility, and are easily scalable. [ABSTRACT FROM AUTHOR]

This study investigates the cradle-to-gate life cycle assessment of four acrylic acid production routes. Acrylic acid, an important industrial chemical, is currently produced using fossil fuel-based propylene but it can be sustainably produced from biodiesel derived glycerol through different pathways that involve intermediates such as acrolein, allyl alcohol, or lactic acid. Environmental impacts, including global warming potential, water footprint, acidification, eutrophication, ozone layer depletion, photochemical smog, and human toxicity, are evaluated. Glycerol-based processes exhibit significant environmental impacts mainly due to the energy-intensive production of epichlorohydrin-derived glycerol. The total potential global warming for glycerol-based processes having intermediates allyl alcohol, lactic acid and acrolein, was 1.67 × 105, 1.80 × 105 and 1.34 × 105 kg CO2 eq. FU-1 respectively, with epichlorohydrinderived glycerol, whilst this value was 0.552 × 105 kg CO2 eq. FU-1 for the propylene-based process. However, changing the source of glycerol to purified crude glycerol from the biodiesel industry results in a considerable reduction of the environmental impact. A sensitivity analysis using the two-factor interaction (2FI) model showed that the global warming potential varies from 0.676 × 105 to 1.45 × 105 kg CO2 eq. FU-1 depending on the purification method used to purify crude glycerol and the glycerol content in the crude glycerol. It showed that a vacuum distillation purification process with 50% glycerol content had the least global warming values. This assessment provides insights into environmental performance trade-offs, guiding efforts towards more sustainable acrylic acid production and emphasizing the potential of using by-products from other industries to enhance the sustainability in chemical production processes. [ABSTRACT FROM AUTHOR]

Arylazo sulfones were used as Photoacid Generators (PAGs) for the visible-light photorelease of strong sulfonic acids to promote the ring opening of epoxides in benign media (DMC/water mixtures) or under neat conditions. Water, alcohols, azide and thiocyanate anions, as well as electron-rich aromatics were used in the role of the nucleophile. The resulting 1,2-disubstituted adducts were formed mostly in >99% yield in a high regioselective fashion. [ABSTRACT FROM AUTHOR]