TEXTILE-SUPPORTED CATALYST
Figure 1. Catalyst is applied to fabric, which then undergoes a few minutes of irradiation with ultraviolet light.
Source: Jiwoong Lee, Max-Planck-Institute für Kohlenforschung.
The researchers used three organic catalysts: a base (dimethylaminopyridine), a sulfonic acid and one that functions both as an acid and a base. The latter catalyst currently is used in the pharmaceutical industry in dissolved form to promote production of a specific stereoisomer. All three catalysts converted around 90% of the feed materials into desired products; the dual-function catalyst's product contained 95% of the desired enantiomer.Use of nylon does limit operating temperature to under 100°–150°C, notes Lee. However, other textiles could be used for higher temperature reactions, he says."Due to a capillary effect of the fabric, clogging can be a problem during a reaction but this can be easily solved by applying a continuous system, which is more efficient than a batch reactor," Lee explains. Otherwise, liquids or physical force can be used to clean the fabric, he notes."[The] next step of our research will be focused on the development of [a] more practical and efficient system of immobilization and its application in the real world, industry," declares Lee. A key challenge is to increase the catalyst loading per gram of textile material, he adds."From now [on], catalysts, reagents, ligands and even 'Merrifield's resin' can be immobilized on the textile permanently, and it's safe, flexible and cheap," concludes Lee.Several research institutes and companies already have expressed interest in cooperating on the development and providing the catalyst on a large scale, Lee says.