A solvent selection guide based on chemometrics and multicriteria decision analysis

Abstract

The selection of suitable solvents is a crucially important subject in a wide range of chemical processes. The study presents a solvent selection guide where 151 solvents were assessed, including a significant number of recently reported bio-based solvents. The assessment procedure involves grouping of solvents according to their physicochemical parameters and ranking within clusters according to their toxicological and hazards parameters. Grouping of solvents resulted in formation of three clusters -nonpolar and volatile (35 solvents), nonpolar and sparingly volatile (35 solvents) and polar ones (81 solvents). The comparison of toxicological and hazard related data indicated that solvents from the third cluster should be preferentially chosen. Within each group, a solvent ranking was performed by means of the TOPSIS procedure based on 15 different criteria. Because of lack of certain data (especially toxicological), different ranking confidence levels were introduced. The highest confidence rankings were performed only for some solvents but with all considered criteria. Low confidence rankings were created for all solvents but were based on certain criteria only. The results of our solvent selection guide (SSG) are generally in agreement with results of others but allow for finer ranking of solvents. The assessment procedure is easy to be adapted to individual chemist's needs and allows to include new solvents to the ranking.

Tools and techniques for solvent selection: green solvent selection guides

“…Renewable feedstocks will need to be embraced to secure the sustainability of the chemical industry [5]. Solvent selection guides have become a vital component in the effort to enhance the greenness of the fine chemical industries, but few attempts have been made to highlight the renewability of solvents or simply just to incorporate solvents of a bio-based origin within these tools [56,65,66]. In addition to ethanol (which is now primarily made from biomass because of its energy uses) [67], and DMSO (made by oxidising the dimethyl sulphide by-product of wood pulping operations) [47], 2-MeTHF is presently the only prevalent example of a neoteric (meaning structurally novel or unconventional) bio-based solvent to feature across solvent selection guides [68].…”

“…Two recently published solvent selection guides have now incorporated unconventional bio-based solvents, published online in the journal Green Chemistry within 2 weeks of each other [56,65]. These tools were not designed for the purpose of describing the sustainability of the solvents, but by including bio-based solvents on an equal footing to conventional solvents some welcome progression is demonstrated.…”

“…The second solvent selection guide to extend its coverage to neoteric solvents is based on a computational similarity clustering of solvents [65]. Revealing their motivation, the authors state "existing solvent selection guides give only quasi-quantitative information about solvent greenness" [65].…”

“…Revealing their motivation, the authors state "existing solvent selection guides give only quasi-quantitative information about solvent greenness" [65]. In this new approach to designing a solvent selection guide, 151 solvents were assessed and grouped according to their physicochemical properties.…”

“…16) [65]. Scores for the ranking are set between 1 and 0, but only the relative position of the solvents is shown in Fig.…”