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In a solvent extraction screening study, several β-branched alcohols in the 14–20 carbons range show improved extractive performance to recover ethanol from aqueous solutions compared to commonly studied solvents such as oleyl alcohol and 1-dodecanol. These β-branched alcohols were selected for screening based on extrapolation of results in earlier work with lower molecular weight aliphatic alcohol solvents, that indicated higher separation factors should be realized when hydroxyl position is mid-chain, and there is branching. Solvent toxicity to a commercial yeast commonly used in fuel ethanol production also was evaluated for these as well as several lower molecular weight alcohols. For the alcohols studied, those containing 12 or fewer carbons were toxic or inhibitory to the yeast; those containing 14 or more carbons were non-toxic and non-inhibitory.

The extended hydrogen bond networks formed by alcohols are good indicators of their capacities to hold water. Results from molecular dynamics simulations on 24 linear alcohol isomers containing 6–12 carbon atoms show the effects of hydroxyl location on bulk hydrogenbonded structures. Calculated oxygen–oxygen radial distributions obtained from simulations were correlated to experimental liquid–liquid solvent extraction studies involving ternary water/ethanol/alcohol systems. It was found that hydroxyl group location determines the primary structure of the bulk alcohol’s hydrogen bond network and that an alcohol’s capacity for water correlates directly to the size of this network. 2006 Elsevier Ltd. All rights reserved.

Velocity modulation spectroscopy has been investigated in the terahertz region, employing pure rotational transitions of ArH + and rotation-tunneling transitions of H3O + to study the competition between pressure broadening and Doppler broadening on the lineshapes, neutral suppression, and modulation efficiency. Velocity modulation is demonstrated to be effective to frequencies as low as 60 cm � 1 , yielding S/N values for ArH + (770/1) that surpass published terahertz FM results by an order