Alternative Solvent Technologies

JAMES P. DeYOUNG and TIMOTHY J. ROMACK MICELL Technologies Inc., Raleigh, North Carolina 27613. JOSEPH M. DESIMONE Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290. 

Fluoropolymers 1 Synthesis, edited by Hougham et al., Plenum Press, New York, 1999. 

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Dr Andrew Hunt was part of the first cohort of students on the course in 2001, and went on to complete his PhD in the group on the extraction of high-value chemicals from British upland plants. As well as being heavily involved in teaching the MSc, he is also the Scientific Leader of the Alternative Solvents Technology Platform at the Green Chemistry Centre of Excellence (GCCE) at York. ... 

Limitations in the VOCs emissions wUl certainly push the shoe industry to use alternative bonding technologies to the current solvent-based surface preparations. Several limitations are found in the removal or substitution of solvents in shoe bonding, such as the use of new equipments and machinery, the modification in the procedure to produce bonding, costs increase, and difficulty in bonding some materials without the use of solvents. 

The field is rapidly developing, and the most important issues also relevant to hydrocarbon chemistry include the development of solventless reactions, use of alternative solvents, and, most important of all, replacement of old technologies with clean catalytic processes. Combinatorial chemistry, a method to produce a large number of chemical compounds rapidly on a small scale, can be regarded as a particularly useful tool from the point of view of environmental protection. 

The conversion of this enormous natural chemical potential to the actual products we want requires chemical technologies and if we are to keep the overall environmental footprint low and build on the head start afforded by renewable feedstocks, these need to be green chemical technologies. Fran Kerton reviews these in Chapter 3. Apart from the tools of biotechnology, some of the key technologies are likely to be alternative solvents - for extraction of valuable plant chemicals and for chemical processing alternative activation methods including microwaves (so... 

While hexane is widely accepted as the most effective solvent used today, there are concerns about its flammability, exposure, and environmental impacts. Research has focused on various alternative solvents in the hopes of finding one with acceptable performance while providing greater safety. Alternative solvents that have received some attention include isopropyl alcohol, supercritical carbon dioxide, and other fluids. However, no economical alternative to n-hexane has been accepted at this point, and the best available control technology emphasizes containment and limiting fugitive hexane emissions. 

Room temperatures ionic liquids (ILs)- salts with melting points below 100°C- have attracted considerable attention as novel reaction media over the last decade. By virtue of their nonflammability, thermal stability and non-volatility ionic liquids have been proposed as alternative solvents receiving serious consideration with the promise of both environmental and technological benefits. Really, recent data showing that commonly used ILs have very low but not null vapour pressures (they can distilled at low pressure), that a large group of ILs is combustible" and some commercially available ionic compoimds are toxic for some aquatic species, have cast a shadow on the "green character of ILs. The instinctive skepticism toward... 

This book is a compilation of papers presented at a 1990International workshop. Six major topes are presented alternative technologies, alternative solvents, solvent recovery and recycling, dealing with low VOCs, treatment for environmentally safe disposal of toxic solvents, and issues for consideration. 

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