Themed collection 2021 Green Chemistry Hot Articles

This Perspective discusses the evolution and promise of the emerging application of ionic liquids for renewable thermal energy storage.

The race to decarbonize our energy systems has led to significant advancement in technologies for harvesting renewable energy, carbon capture and conversion.

This perspective reviews the current status and prospects of biocatalysis in ionic liquids.

The enormous dimensions of sustainable energy transitions and their overarching systemic nature require adequate responses from chemical science.

The research works on preparation and application of biomass derived methyl levulinate were summarized. The problems, corresponding solutions, and future research directions in this field were proposed.

This review addresses the current literature on porous organic polymers (POPs) as a new class of metal free green heterogeneous catalysts.

Reductive depolymerization allows the valorization of polyester, polycarbonate and polyamide waste in a wide variety of value-added compounds with good yields

We provide a review of the progress of cross-dehydrogenative coupling reactions in constructing a wide variety of C–C bonds. Sustainable cross-dehydrogenative coupling reactions can be combined with multiple forms of energy output.

Development of active materials in aqueous organic redox flow battery contributes to the aspect of green technology. The ‘greenness’ of synthetic methodologies for preparing active materials are evaluated using the 12 principles of green chemistry.

This review presents the recent progress of the photocatalytic conversion of CH₄ to CH₃OH from four aspects: photocatalysts, oxidants, sacrificial reagents, and CH₄ activation mechanisms, along with its current status and existing challenges.

Cellulose building blocks can be assembled into lightweight materials with properties tailored by the density and the morphology.

It's not only lipases which can be applied in alternative solvent systems to meet industrial and environmental demands. At the hand of case studies and flowcharts this review quickly shows what solvent systems are viable.

One-pot tandem procedures represent a green and general approach towards process intensification as they are intrinsically simpler compared to the conventional stepwise processes, do not require intermediate isolation and are generally more efficient.

Changes of Gibbs free energy made insights into the carbon fixation pathways from thermodynamic perspective.

This review presents the conversion routes, processing strategies, state-of-the-art technical advances, challenges and perspectives in hydrothermal amination of N-rich biomass sources and N-free biomass feedstocks to nitrogenous chemicals.

This review surveys continuous flow approaches for the synthesis of chiral APIs and their advanced stereogenic intermediates, covering the utilization of biocatalysis, organometallic catalysis and metal-free organocatalysis to introduce asymmetry.

This research could provide a guideline for implementing green chemistry principles into spent LIBs recycling.

Emission of fibrous microplastics from synthetic textile washing to the aquatic environment via wastewater treatment plant and reduction measures.

A review of thermal and thermocatalytic valorization of food waste into biobased platform chemicals. A detailed summary of process level and fundamental kinetic insights are provided towards upgrading FW to useful products for a circular economy.

Advances and strategies of electrocatalytic CO₂ conversion to alcohols on Cu-based catalysts is assessed with an outlook of current challenges for a practical application of this technology.

This paper summarizes the existing hydrothermal liquefaction process literature and reveals the effect of process parameters on the bio-crude yield.

In this critical review, the recent advances of the CO₂-assisted catalytic dehydrogenation of light alkanes are summarized.

Instead of focusing on maximizing glycosylation yield, future syntheses of nucleosides via N-glycosylation should aim to use shorter routes, fewer protecting groups and less chromatography to achieve more efficient and sustainable processes, as this E-factor analysis reveals.

Stepwise oxygenation of benzylic molecules with uranyl photocatalysis was realized under ambient conditions. The accuracy of the stepwise oxygenation was ensured by the tunability of redox potential in uranyl photocatalysis through solvents and additives.

Cholinium-based eutectic solvents as a promising and sustainable solution for the extraction of carotenoids from microbial biomass and the preparation of biodegradable active biofilms.

Organosolv pulping performed in a high-pressure Soxhlet extractor using carbon dioxide as a mild and recyclable acid is described.

An iron-catalysed photoredox alkynylation of methane, ethane, and other light alkanes is developed as a concise and efficient approach to valuable internal alkyne synthesis.

A flow reactor was designed, manufactured by 3D printing, and modified to promote the selective ethanolysis of a chemical warfare agent VX surrogate.

Although iron catalyzed cross-couplings show extraordinary promise in reducing the environmental impact of more toxic metals, one of the main challenges is the use of reprotoxic NMP (NMP = N-methylpyrrolidone) as the key ligand.

We hybridised lignocellulose microfibres with a fungal derived nanoscale chitin-β-glucan network produce hydrophobic papers with improved tensile properties.

A visible light-induced metal-free C(sp³)–H phenanthridinylation of simple alkanes with isonitrile is developed with H₂O₂ as a terminal sustainable oxidant.

A strategy was developed to obtain Cu–N₃ sites in a Cu–N-doped carbon-based catalyst by utilizing metal ionic liquid as a precursor. The catalyst showed a high CO faradaic efficiency and a high current density within a wide potential range.

A facile and efficient method for bioplastic degrading microorganism screening based on a micro-spray system is developed. The potential of this approach was validated by isolating various bioplastic degrading bacteria from the activated sludge.

Flow-through solvolysis offers an opportunity to limit lignin condensation reactions that prevent isolation of native lignin in biomass processing, thus allowing for the study of intrinsic lignin properties and steady-state lignin depolymerization.

Here, we demonstrate for the first time the formation of Zn-Bi₂WO₆ microflowers for the simultaneous photocatalytic CO₂ reduction and benzylamine oxidation in absence of sacrificial agent or oxidant, and achieve high efficiency of energy utilization.

A facile and green S-glycosylation method is developed, in which Ca(OH)₂ promoted the coupling of protection-group-free fluoride donors and thiol acceptors in water, affording various thioglycosides and thioglycopeptides.

A sustainable synthesis of spiroindolenines from tryptamine-derived isocyanides and organic azides in pure water was described.

The discovery of iron(II) bromide and cerium(III) bromide as a bifunctional catalyst enables the oxidative rearrangement of indoles with hydrogen peroxide as the terminal oxidant.

The “3C-tuning” via chemical designing and nanocompositing upgrades mechanical performances of poly(butylene succinate) to a remarkable level with accelerated biodegradation.

Aqueous chemoenzymatic two-step one-pot enantioselective synthesis of tertiary α-aryl cycloketones via Pd-catalyzed C–C formation and enzymatic CC asymmetric hydrogenation was developed.

Surface-active imidazolium nitrates activate hydrogen peroxide, which enables the epoxidation of olefins. The micelles solubilise the substrate in the aqueous oxidant phase and allow for simple product separation and catalyst recycling.

An atom economic synthesis of dense porous layered double hydroxides (SLDHs) using an undesirable waste in wastewater treatment plants (struvite) is reported. The obtained SLDHs show high specific surface area, large pore volume and high density.

The Aldehyde-Water Shift (AWS) reaction uses H₂O as a benign oxidant to convert aldehydes to carboxylic acids, producing H₂, a valuable reagent and fuel, as its sole byproduct.

Bifunctional organocatalysts bearing diamine and carboxylic acid groups efficiently catalyze the coupling reaction of CO₂ with epoxides under halogen-free conditions due to a synergy effect.

A sustainable flow process has been established for the application of the Gröebke–Blackburn–Bienaymé reaction for access to high-value fused heteroaromatics.

A multi-component reaction of arylamines, elemental sulfur and CO₂ (1 atm) is reported to generate valuable thiazolidin-2-ones and 1,3-thiazinan-2-ones in moderate to good yields under transition-metal-free reaction conditions.

4-Cyclohexylmorpholines could be efficiently synthesized from reductive coupling of aryl ethers (including the typical lignin model compounds) with morpholines over Pd/C without using any acidic additives.

Crystallisations on both the academic and industrial scale often use large volumes of solvent.

Recycling of end-of-life polyvinyl chloride (PVC) calls for solutions to deal with the vast amounts of harmful phthalate plasticizers that have historically been incorporated in PVC.

Comprehensive HT-GC × GC FID/MS enables reliable detection and quantification of RCF lignin monomers, dimers and, trimers.

Caprolactam anionic polymerization was used to achieve suitable melt viscosity for drawing into ultra-fine fibers. The process temperature was well below that of the melting point of nylon 6.

Linear water soluble cellulosic poly(protic ionic liquid) electrolytes were facilely and atom economically prepared after dissolution of cellulose in a DBU/CO₂/DMSO solvent system, and can be used as an efficient catalyst for the Knoevenagel condensation reaction in water.

A water-removable ynamide coupling reagent for racemization-free construction of amide and ester bonds was reported. No column chromatography purification was involved because acidic aqueous work-up removed the byproduct completely.

A family of new bio-based surfactants have been prepared via the epoxidation and PEGylation of lactonic sophorolipids. This modification enhances their performance and diversifying their potential applications.

As a biomass tanning agent, epoxy-modified dialdehyde starch can significantly improve the comprehensive properties of finished leather, and is expected to be a novel sustainable chrome-free tanning agent replace traditional tanning agent.

Starting from polyphenylene oxide plastic, the selective production of 3,5-dimethyl phenol as an important pharmaceutical intermediate was achieved over Ru/Nb₂O₅, which is the first example of integrating waste plastic into the drug supply chain.

Thermogalvanic devices require anionic and cationic species; the rational development of safe(r) iron-based anionic redox couples was explored.

Nano-micelles meet biogenic Pd nanoparticles at the cell membrane promoting Suzuki Miyaura coupling reactions under mild conditions.

It is demonstrated that temperature-controlled ball milling is a key component for scaling up small-scale mechanochemistry.

The promotion efficiency of organic solvents in biphasic systems for furfural production is influenced by four factors, and the most important factor is the solvation free energy of furfural (ΔG_sol-ff) in organic solvents.

Core–shell RuNi catalysts are prepared from organometallic complexes and PVP as stabilizers under one-pot conditions. The synergistic effect between Ru and Ni activity in furfural hydrogenation depends on the nanoparticle composition.

In this study, an environment-friendly and efficient artificial Vitreoscilla hemoglobin (VHb) for the synthesis of 2-aminobenzoxazoles and 2-aminobenzothiazoles has been reported.

We fed furfurylated and control wood to gribble. Our results imply that furfurylation of wood protects against degradation by gribble without the reliance on broad spectrum biocides and can reduce costs associated with damaged wooden structures.

Furfural-based hardener for cross-linking flexible epoxidized linseed oils leading to bulky biobased thermosets with high hardness and good ultimate strength.

Combining CO₂ and H₂ for chemo- and regioselective hydroformylation of alkenes has been realized. The key to success is the use of a bifunctional Rh/PTA catalyst, which can ingeniously combine efficient CO₂ hydrogenation and hydroformylation.

Cyclic organic carbonates can be prepared directly from various terminal olefins via green tandem tungstate-based catalysis.

Optimized electronic structures of Fe₃C/NC boosted NH₃ production from nitrate electroreduction, which proceeded via a stepwise NO₃⁻–NO₂⁻–NH₃ pathway.

A practical and environment-friendly methodology for the construction of sulfonyl quinolines through ball milling promoted coupling of haloquinolines with sulfonic acid under metal-, base-, solvent- and additive-free conditions was developed.

The first developed ionozyme that combines a discovered novel FDHPa with a synergistic ionic microenvironment enables efficient bioactivation of CO₂.

A practical and green iron-catalyzed photoredox system for C–H functionalization of ethane, propane, and other light alkanes was developed.