Sustainable Chemical Manufacturing Research Articles

Iron-, Cobalt-, and Nickel-Catalyzed Asymmetric Transfer Hydrogenation and Asymmetric Hydrogenation of Ketones.

Chiral alcohols are important building blocks in the pharmaceutical and fine chemical industries. The enantioselective reduction of prochiral ketones catalyzed by transition metal complexes, especially asymmetric transfer hydrogenation (ATH) and asymmetric hydrogenation (AH), is one of the most efficient and practical methods for producing chiral alcohols. In both academic laboratories and industrial operations, catalysts based on noble metals such as ruthenium, rhodium, and iridium dominated the asymmetric reduction of ketones. However, the limited availability, high price, and toxicity of these critical metals demand their replacement with abundant, nonprecious, and biocommon metals. In this respect, the reactions catalyzed by first-row transition metals, which are more abundant and benign, have attracted more and more attention. As one of the most abundant metals on earth, iron is inexpensive, environmentally benign, and of low toxicity, and as such it is a fascinating alternative to the precious metals for catalysis and sustainable chemical manufacturing. However, iron catalysts have been undeveloped compared to other transition metals. Compared with the examples of iron-catalyzed asymmetric reduction, cobalt- and nickel-catalyzed ATH and AH of ketones are even seldom reported. In early 2004, we reported the first ATH of ketones with catalysts generated in situ from iron cluster complex and chiral PNNP ligand. Since then, we have devoted ourselves to the development of ATH and AH of ketones with iron, cobalt, and nickel catalysts containing novel chiral aminophosphine ligands. In our study, the iron catalyst containing chiral aminophosphine ligands, which are expected to control the stereochemistry at the metal atom, restrict the number of possible diastereoisomers, and effectively transfer chiral information, are successful catalysts for enantioselective reduction of ketones. Among these novel chiral aminophosphine ligands, 22-membered macrocycle P2N4 exhibited extraordinary enantioselectivities when combined with iron(0) cluster Fe3(CO)12. A broad scope of ketones including aromatic, heteroaromatic, and β-ketoesters can be reduced smoothly with excellent enantioselectivities (up to 99% ee) approaching or exceeding those achievable with the noble metal catalysts. Notably, the chiral iron-based catalyst proved to be highly efficient for both ATH as well as AH of various ketones. Until now, such "universal" catalyst is very rare. Preliminary studies suggest that the AH reaction most likely involved iron particles as the active catalytic species. These research results point to a new direction in developing viable effective nonprecious metal catalysts for asymmetric reduction and probably for other asymmetric catalytic reactions as well.

Continuous Flow Synthesis of RAFT Block Copolymers

Ivan Martinez-Botella obtained a five-year degree in chemistry from the University of Alicante (Spain) in 2010. As an undergraduate, Ivan participated in ERASMUS and IAESTE exchanges, working in organic synthesis at the University of Newcastle upon Tyne (UK) and CSIROMolecular &Health Technologies (Australia) between 2007 and 2009. In 2012, he joined CSIRO Materials Science & Engineering to work on continuous flow synthesis in collaboration with the Victorian Centre for Sustainable Chemical Manufacturing (VCSCM).

Sustainability of the chemical manufacturing industry—Towards a new paradigm?

This paper describes the current situation of the chemical manufacturing industry, with special reference to Europe and looks to the future sustainability demands on the sector, and the implications of these demands for chemical engineering education. These implications include definitions of sustainability criteria for the sector and the need for transparent reporting under the Triple Bottom Line approach. The response of the education system to the sustainability agenda over the years and a number of strategies to incorporate it into courses are described. The important role of chemical (or more generally, process) engineers in delivering sustainable solutions is emphasised but this also suggests that a new way of thinking about the discipline is required. Indeed, this paper argues that the demand for a sustainable chemical manufacturing sector could bring about the next paradigm shift in the discipline which has been predicted for some time.

Sustainable Chemical Manufacturing: A Matter of Resources, Wastes, Hazards, and Costs.

Sustainable development is gaining importance in the chemical industry. It encompasses social, environmental, and economical aspects. Herein, sustainable development is translated into four basic dimensions, called "sustainability stresses": resources, wastes, hazards, and costs. These sustainability stresses are discussed in some detail and their usefulness is illustrated by applying them to three manufacturing processes applied commercially by Shell, namely Shell's OMEGA, SMPO, and "low monol" technologies for producing ethene diol, styrene/propene oxide, and polyether polyols, respectively. These examples show that large reductions in sustainable stresses have been achieved in a few decades. They also show that the economical, environmental, and social issues are not in conflict when tackled at their roots: they can be all addressed simultaneously.

Green chemistry for the second generation biorefinery—sustainable chemical manufacturing based on biomass

AbstractThe material needs of society are reaching a crisis point. The demands of a growing and developing world population will soon exceed the capacity of our present fossil resource based infrastructure. In particular, the chemical industry that underpins most industries needs to respond to these challenges. The chemical manufacturing and user industries face an unprecedented range and intensity of drivers for change, the greatest of which, REACH (Registration, Evaluation and Authorisation of Chemicals) has yet to bite. In order to address the key issues of switching to renewable resources, avoiding hazardous and polluting processes, and manufacturing and using safe and environmentally compatible products, we need to develop sustainable and green chemical product supply chains. For organic chemicals and materials these need to operate under agreed and strict criteria and need to start with widely available, totally renewable and low cost carbon—the only source is biomass and the conversion of biomass into useful products will be carried out in biorefineries. Where these operate at present, their product range is largely limited to simple materials (e.g. cellulose), chemicals (e.g. ethanol) and bioenergy/biofuels. Second generation biorefineries need to build on the need for sustainable chemical products through modern and proven green chemical technologies such as bioprocessing, controlled pyrolysis, catalysis in water and microwave activation, in order to make more complex molecules and materials on which a future sustainable society will be based. Copyright © 2007 Society of Chemical Industry

Optimal regulations for sustainable chemical manufacturing

Environmental regulations typically follow a command-and-control approach mandating the installation of state-of-the-art abatement technology and imposing hard emission thresholds. However, this type of regulations does not encourage process improvement and technological research to reduce emissions. In contrast, market-based environmental regulations stimulate continued improvement of cleaner manufacturing practices by creating economic incentives for sustained emission reduction. This paper aims at furnishing regulators and manufacturers with a tool to assess the impact of future regulatory scenarios using realistic chemical engineering models of pollution abatement operations.