Sustainable Chemistry

The catalytic activity of the vanadium-dependent bromoperoxidase isolated from the brown alga Ascophyllum nodosum is compared with the activity of a cheap, commercially available V-catalyst precursor in the bromination of thymol. Organic solvents have been avoided to make the system appealing from a sustainable chemistry point of view. It is noteworthy that, notwithstanding the low solubility of the substrate, the thymol bromination reactions were performed

The mitigation and utilization of greenhouse gases, such as carbon dioxide and methane, are among the most important challenges in the area of energy research. Dry reforming of CH4 (DRM), which uses both CO2 and CH4 as reactants, is a potential method to utilize the greenhouse gases in the atmosphere. Natural gas containing high concentrations of CO2 and CH4 could therefore be utilized for hydrogen and synthesis gas (syngas) production in the near future, without need for the removal of CO2 from the source gas. Thus, the DRM reaction is a suitable process to convert CH4 and CO2 to syngas, which is a raw material for liquid fuel production, through the Fischer–Tropsch process. Herein, the development of CO2 reforming for syngas production is reviewed, covering process chemistry, catalyst development, and process technologies as well as the potential future direction for this process.

The rapid growth, demand, and production of batteries to meet various emerging applications, such as electric vehicles and energy storage systems, will result in waste and disposal problems in the next few years as these batteries reach end-of-life. Battery reuse and recycling are becoming urgent worldwide priorities to protect the environment and address the increasing need for critical metals. As a review article, this paper reveals the current global battery market and global battery waste status from which the main battery chemistry types and their management, including reuse and recycling status, are discussed. This review then presents details of the challenges, opportunities, and arguments on battery second-life and recycling. The recent research and industrial activities in the battery reuse domain are summarized to provide a landscape picture and valuable insight into battery reuse and recycling for industries, scientific research, and waste management.

Dehydration mechanism Sustainable chemistry a b s t r a c t Biomass-derived 5-hydroxymethylfurfural (HMF) has been emerged as a key platform chemical for the production of fine chemicals and liquid fuels. The direct transformation of cellulose and lignocellulosic biomass into HMF in ionic liquids and organic solvents is most desired in terms of process economics and sustainability. The focus of this review is purely on the HMF production from cellulose and lignocelluloses and mechanistic aspects of HMF formation in order to bridge the gap in understanding the factors responsible for selective conversion and selection of catalyst. Additionally, present review is devoted exclusively to the latest developments, namely microwave-assisted degradation of cellulose to HMF, application of solid acid and ionic-liquid catalysis to address their effectiveness for HMF production. Approaches for the cellulose transformation into HMF are especially emphasized in order to explore newer avenues of biomass as renewable feedstock for energy and chemicals. ª b i o m a s s a n d b i o e n e r g y 5 5 ( 2 0 1 3 ) 3 5 5 e3 6 9 0961-9534/$ e see front matter ª b i o m a s s a n d b i o e n e r g y 5 5 ( 2 0 1 3 ) 3 5 5 e3 6 9

We present a review on the multifunctional use of ionic liquids with respect to lignin processing. In a biorefinery context, lignocellulosics could be used to provide sustainable sources of fuels such as bioethanol, and feedstock molecules for the chemical industry such as phenols and other aromatics. However, separation of lignin from cellulose and hemicellulose is a vital step. Ionic liquids can dissolve extensive quantities of biomass, and even be designed to be multifunctional solvents. We highlight the use of ionic liquids in selectively or non-selectively dissolving lignin, the depolymerization reactions that have been attempted on lignin in ionic liquids, and the effect ionic liquids have been observed to have on such processes. Finally, we present some of the challenges and issues that must be addressed before the informed and large-scale application of ionic liquids can be realized for lignin processing.

http://dx.doi.org/10.1071/CH12324

Endocrine-disrupting compounds (EDCs) are exogenous compounds that interfere with the normal hormone functions and ultimately lead to health disorders. Parabens, phenols, and phthalates are well-known EDCs, produced globally in large quantities and widely used in a variety of applications. Several studies have monitored these compounds in a variety of environmental matrices, including air, water, sediment, fish, human tissues, soil, indoor dust, and biosolids, etc. In recent years, environmental contamination and human exposure to these chemicals have become a great concern, due to their residue levels exceeding the permissible/acceptable limits. In this review, we focus on the origin of these EDCs, aquatic contamination pathways, distribution, human exposure, health implications, and healthcare costs. Further, this review identifies critical challenges and future research needs in removing or minimizing environmental contamination and exposure to these chemicals to protect living r...

The combustion of fossil fuels is intensifying global warming and destructing the ecosystem with negative human health impacts as well. Even so, other anthropogenic activities have unfortunately constituted pollution also to our environment, say, in the form of waste waters. Beside these, the existing technologies for waste water treatment have problems such as high costs, sludge disposal challenges, etc. Thus, it is now important to find economically viable and safe alternatives to decontaminate waste waters. Hence, low cost, renewable, easily accessible, and readily prepared biosorbents have become favourable alternatives to traditional counterpart for the elimination of pollutants from aqueous systems. Fortunately, these biosorbents also have requisite and comparable properties necessary for adsorption of pollutants. Many studies have been reported on the application of biosorbents for pollutants removal. However, this paper provides an overview of biosorbents preparation, proper...

Polymers are essential materials in our daily life. The synthesis of value-added polymers is mainly performed from fossil fuel-derived monomers. However, the adoption of the circular economy model based on the bioeconomy will reduce the dependence on fossil fuels. In this context, biorefineries have emerged to convert biomass into bioenergy and produce high value-added products, including molecules that can be further used as building blocks for the synthesis of biopolymers and bioplastics. The achievement of catalytic systems able to polymerize the natural monomer counterparts, such as terpenes or terpenoids, is still a challenge in the development of polymers with good mechanical, thermal, and chemical properties. This review describes the most common types of bioplastics and biopolymers and focuses specifically on the polymerization of terpenes and terpenoids, which represent a source of promising monomers to create bio-based polymers and copolymers.

of scientific literacy (Roberts, 2007) and the ideas of Education for Sustainable Development (ESD) (Burmeister, Rauch & Eilks, 2012). This paper will discuss all the three frameworks (relevance; scientific literacy; ESD) and try to identify whether and in which degree they overlap in guidance for chemistry education curriculum reform. This will be illustrated by two classroom examples from Germany and Israel. Three suggested frameworks for educational reform in chemistry education Understanding the meaning of relevance in science education 'Relevance' is a frequently used term when educational reforms are conducted. Teachers are supposed to provide students with 'more relevant' education in order to motivate them and make them curious about science (Holbrook, 2005). However, it is not always clear what is meant by making science education 'relevant'

Herein, we present the first unambiguous evidence for hydrated reverse micelles (RMs) in dense or supercritical carbon dioxide (scCO2). These RMs are formed with a low cost designer triple hydrocarbon chain surfactant, sodium 1,4-bis(neopentyloxy)-3-(neopentyloxycarbonyl)-1,4-dioxobutane-2-sulfonate (TC14).

The eco-sustainable use of materials derived from agricultural and food processing waste will represent one of the most stimulating challenges shortly. Chitin and chitosan are two remarkable examples of how molecules with high added value can be extracted from food waste, such as crustaceans’ shells, fungi, mollusks, etc. This Perspective summarizes the current state of knowledge about chitin extraction, chitosan production, and hydrogel formation, highlighting the environmental critical steps in the common route (use of strong acids and basis, toxic solvents, and not eco-friendly crosslinkers). At the same time, promising green alternatives are described and analyzed. Examples are the employment of NADESs or DESs (such as choline chloride: urea or choline chloride: organic acids mixtures) for chitin extraction and dissolution, use of citric acid both in chitin extraction and hydrogel formation or utilization of natural extracts, like genipin, as green cross-linkers under mild condi...

This study compared the yield of biodiesel produced from tall oil fatty acids (TOFA) via (i) homogeneous catalyst (sulfuric acid) and (ii) a heterogeneous catalyst (Amberlyst® BD20, together with Ambersep BD 19 (Midcontinental Chemical Co., Olathe, KS, USA)® using a batch reactor. The effect of operation conditions including temperature, catalyst concentration, methanol: oil ratio and reaction time on esterification yield were investigated. Gas chromatographic data showed that the major fatty acids present in the TOFA are oleic acid (C18:1n9) and linoleic acid (C18:2n6). Homogenous catalysis yielded 96.76% biodiesel compared to 90.24% for heterogeneous catalysis. Optimized conditions for homogenous catalysis were at a catalyst concentration of 0.5 w/w%, 15:1 methanol: oil mass ratio at 55 °C for 60 min. FTIR results also showed that the homogeneous catalyst yielded a more complete reaction toward biodiesel production in a shorter time (60 min) compared to the heterogeneous catalyst ...

Nitrogen oxides NO x , which include NO (nitrogen monoxide), NO 2 (nitrogen dioxide), and N 2 O (nitrous oxide), are currently considered to be among the most dangerous air pollutants, as they cause acid rain, contribute to photochemical smog, and have direct harmful effects on human health. For all these reasons, in the last decades NO x emissions have been regulated in industrialized countries by more and more restrictive legislation. Selective catalytic reduction (SCR) technology is well established and used worldwide to control NO x emissions from power plants and other stationary sources. A hot exhaust gas is passed over an extruded honeycomb monolith catalyst consisting of V 2 O 5 -WO 3 /TiO 2 [2] in the presence of a nitrogenous reductant such as ammonia or urea (an ammonia carrier), which converts NO x to nitrogen according to the so-called standard SCR reaction (1).

The large-scale, cost-effective storage of electrical energy obtained from the growing deployment of wind and solar power is critically needed for the integration into the grid of these renewable energy sources. Rechargeable batteries having a redox-flow cathode represent a viable solution for either a Li-ion or a Na-ion battery provided a suitable low-cost redox molecule soluble in an aprotic electrolyte can be identified that is stable for repeated cycling and does not cross the separator membrane to the anode. Here we demonstrate an environmentally friendly, low-cost ferrocene/ferrocenium molecular redox couple that shows about 95 % energy efficiency and about 90 % capacity retention after 250 full charge/discharge cycles.

A growing environmental concern is leading the chemical industry to develop environmentally benign products and processes. a,b-Unsaturated carbonyl compounds are important intermediates, however, their synthesis requires several steps and produces toxic wastes. The catalytic behavior of a Mg,Al-mixed oxide, derived from thermal decomposition of a hydrotalcite and an X zeolite exchanged with cesium and impregnated with cesium species was studied using the aldol condensation reaction between glyceraldehyde acetonide and acetone producing the corresponding a,b-unsaturated carbonyl compound. These catalysts were active for the studied reaction. The product distribution has shown that besides the principle product, other compounds obtained from different aldol reactions were observed. The rehydration of the Mg,Al-mixed oxide generated a catalyst that was selective to the condensation product of glyceraldehyde acetonide and acetone. The decrease of reaction temperature favored the formation of the main product over the Mg,Al-mixed oxide sample. #

Scheme 1. Three-component system for the photocatalytic proton reduction. SR = sacrificial reductant, PS = photosensitizer, WRC = water reduction catalyst. Pathway A (red): reductive quenching cycle; Pathway B (blue): oxidative quenching cycle.

Sustainable development now plays an increasingly important role in the strategy of chemical industries. As a part of this preoccupation, the search for more economic and more ecofriendly new efficient synthetic methods is of vital concern. The development of iron-catalyzed cross-coupling reactions is one of the current promising fields of research, as these reactions are very attractive compared to the related palladium-or nickel-catalyzed procedures extensively used until now. This is well illustrated by the numerous results published by us [1] and others. Note that for large-scale applications, it is not enough to use iron salts as catalysts; it is also important to use cheap ligands in small amounts as well as solvents that are compatible with industrial processes.

We have developed a general economical and environmentally benign method for the preparation of isothiocyanates from the corresponding dithiocarbamic acid salts by using cheap and readily available reagent molecular iodine. This is perhaps the most efficient method reported so far for the synthesis of isothiocyanates. The reagent is easily available and nontoxic, and the precipitated sulfur can be removed easily; hence, this method is most suitable for large-scale synthesis.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

The Pycnoporus fungi are white-rot basidiomycetes listed as food-and cosmetic-grade microorganisms. Three high redox potential laccases from Pycnoporus coccineus and Pycnoporus sanguineus were tested and compared, with the commercial Suberase® as reference, for their ability to synthesise natural active oligomers from rutin (quercetin-3-rutinoside, one of the best-known naturally occurring flavonoid glycosides). The aim of this work was to develop a process with technical parameters (solvent, temperature, reaction time and raw materials) that were easy to scale up for industrial production and compatible with cosmetic and pharmaceutical formulation guidelines. The aqueous mixture of glycerol/ethanol/buffer described in this study met this requirement and allowed the solubilisation of rutin and its oxidative bioconversion into oligomers. The four flavonoid oligomer mixtures synthesised using laccases as catalysts were analysed by high performance liquid chromatography-diode array detectionnegative electrospray ionisation-multistage mass spectrometry. Their chromatographic elution profiles were compared and 16 compounds were characterised and identified as dimers and trimers of rutin. The oligorutins were different in Suberase® and Pycnoporus laccase reaction mixtures. They were evaluated for their antioxidant, antiinflammatory and anti-ageing activities on specific enzymatic targets such as cyclooxygenase (COX-2) and human matrix metalloproteinase 3 (MMP-3). Expressed in terms of IC 50 , the flavonoid oligomers displayed a 2.5-to 3-fold higher superoxide scavenging activity than monomeric rutin. Pycnoporus laccase and Suberase® oligorutins led to an inhibition of COX-2 of about 35% and 70%, respectively, while monomeric rutin showed a nearnegligible inhibition effect, less than about 10%. The best results on MMP-3 activity were obtained with rutin oligomers from P. sanguineus IMB W006-2 laccase and Suberase® with about 70-75% inhibition.

Energy efficient and sustainable process for the production of 5-hydroxymethylfurfural (HMF) from carbohydrates is highly demanding. Here, direct conversion of carbohydrates into HMF has been investigated over self-assembled mesoporous TiO 2 nanoparticles (NPs) catalyst. Monosachharides d-fructose and dglucose, disaccharides sucrose, maltose, cellobiose were successfully converted into HMF with variable yields in both aqueous and organic mediums under microwave-assisted heating conditions. The effects of solvent polarity, microwave absorbing ability, catalyst loading, reaction time, and substrate variations on the HMF yields have been studied. Pyridine-IR and NH 3 -TPD analyses confirmed the presence of Lewis acidic sites, whereas N 2 sorption analysis revealed high BET surface area for the self-assembled mesoporous TiO 2 nanomaterials synthesized by using sodium salicylate as template. High surface area, Lewis acidity and uniform nanosphere-like particle morphology are responsible for high catalytic activity in the dehydration of carbohydrate substrates over this mesoporous TiO 2 nanomaterial, whereas commercially available TiO 2 is almost inactive for this dehydration reaction under similar conditions. The higher microwave energy absorbing ability (tan ı) of the DMSO and NMP resulted in higher HMF yield in organic solvents than water. Catalyst life-time analysis suggested that mesoporous TiO 2 NPs catalysts can be recycled for four catalytic cycles without appreciable loss of its catalytic activity.

Amino acid ionic liquids (ILs) are the most interesting and effective for CO2 capture due to their low toxicity, biodegradability, and fast reactivity toward CO2. The ionic nature of amino acid ILs can raise an environmental issue if the cation counterpart becomes toxic to the aquatic ecosystems, and they can become potential atmospheric pollutants. In this regard, choline based ILs are known to be promising scaffolds for the development of less toxic amino acid ILs. However, the existing choline amino acid ILs are highly viscous, limiting their applicability as solvents. Ether functionalized choline based amino acid ILs with a novel series of less toxic green ILs were explored with reduced viscosity and high CO2 capture capacity. A simple, economic, clean, and environmentally benign method was utilized for the synthesis of novel choline based amino acid ILs using a commercially available and economical starting material, 2-(dimethylamino)ethanol (deanol, a human dietary food supplement). These ILs have low viscosity with high CO2 capture capacity (1.62 mol of CO2 /mol of IL, 4.31 mol of CO2/kg of IL, 19.02 wt % of CO2). The mechanism of [N1,1,6,2O4][Lys] + CO2 reaction and adduct structure was proposed by using DFT calculations, and IR and NMR spectroscopic techniques.

Neodymium (Nd) is one of the most essential rare-earth metals due to its outstanding properties and crucial role in green energy technologies such as wind turbines and electric vehicles. Some of the key uses includes permanent magnets present in technological applications such as mobile phones and hard disk drives, and in nickel metal hydride batteries. Nd demand is continually growing, but reserves are severely limited, which has put its continued availability at risk. Nd recovery from end-of-life products is one of the most interesting ways to tackle the availability challenge. This perspective concentrates on the different methods to recover Nd from permanent magnets and rechargeable batteries, covering the most developed processes, hydrometallurgy and pyrometallurgy, and with a special focus on electrodeposition using highly electrochemical stable media (e.g., ionic liquids). Among all the ionic liquid chemistries, only phosphonium ionic liquids have been studied in-depth, explo...

A new fuel additive, namely solketal tert-butyl ether (STBE), was developed and optimized under continuous flow conditions using a Corning Ò Advanced-Flow™ glass reactor. STBE was obtained in two steps from glycerol, a renewable building-block produced in large amount in the processing of biodiesel. The advantages of the highly engineered Corning glass reactor included high mixing and heat-exchange efficiency, chemical resistance under corrosive flow conditions and a small hold-up. A robust, continuous, green and safe industrial-scale process is described.

through Cooperative Agreement DE-FC02-07ER64494 between The Board of Regents of the University of Wisconsin System and the U.S. Department of Energy. We thank Prof. Christos Maravelias, Sercan Murat Sen, and Jee-hoon Han for valuable discussions and help with ASPEN simulations.

The pressing concerns of environmental sustainability and growing needs of clean energy have raised the demands of carbon and organic based energy storage materials to a higher level. Redox-active organic-carbon composites electrodes are emerging to be enablers for high-performance, high power and long-lasting energy storage solutions, especially for electrochemical capacitors (EC). This review discusses the electrochemical redox active organic compounds and their composites with various carbonaceous materials focusing on capacitive performance. Starting with the most common conducting polymers, we expand the scope to other emerging redox active molecules, compounds and polymers as well as common carbonaceous substrates in composite electrodes, including graphene, carbon nanotube and activated carbon. We then discuss the first-principles computational studies pertaining to the interactions between the components in the composites. The fabrication methodologies for the composites wit...

A highly efficient and ligand-free copper(I) sulfide catalyzed cross-coupling reaction of aryl iodides with diaryl disulfides was developed. With only 1 mol-% of Cu 2 S as the catalyst, iron powder as the reductant, and K 2 CO 3 as the base, aryl

We extended the three-phase transport methodology to the catalytic hydroformylation of alkenes. The method enables to carry out an all-hydrophobic reaction -substrate, product and catalyst -in water. The alkene is microemulsified in the aqueous medium and the solubilized substrate is assumed to be carried to an organometallic rhodium catalyst entrapped within a partially hydrophobicized silica sol-gel matrix. The substrate is then spilled into the porous heterogenized catalyst in which the hydroformylation takes place. The products

The development of chemical reactions catalysed by homogeneous organometallic complexes has allowed a significant breakthrough in synthesis chemistry, but now research axes must integrate catalysts recycling at the early stage of their conception. Catalyst recycling by nanofiltration in organic solvent (OSN) may represent an innovative route since this separation process at a molecular level is a low energy consumer. Challenges for OSN are membrane stability in organic solvents and the mastering of filtration conditions. Molecular engineering of catalysts based on slight structural modifications is also proposed to associate activity and high retention for OSN recycling. This paper deals with the integration of OSN within the homogeneous catalytic olefin metathesis reaction.