Speciality Chemicals Magazine JUL / AUG 2021 | Page 26

“ Cyrenecanbeused acrossarangeofkey markets . Inparticular , ithassignificant advantagesinthe sustainableproduction ofmaterial "
Membranes & nanoparticles
‣ Cyrene has also shown increased performance in the production of membranes and nanoparticles when compared to traditional fossilbased solvents . 2 Independent work at the University of York and the Institute of Membrane Technology ( IMT ) in Italy showed that Cyrene was an excellent solvent for the production of polyethersulfone membranes for water filtration . These membranes could be cast under hot ( 70 ° C ), cold ( 17 ° C ) or via phase inversion methods . This research was extended to the formation of both polyvinylpyrrolidone ( at York ) and polyvinylidene fluoride ( PVDF , at IMT ) water filtration membranes . Another recent report from Brawijaya University in Indonesia describes the use of Cyrene as a sustainable solvent for the fabrication of cellulose triacetate-based osmosis membranes . 3 Researchers at the University of Melbourne also formed polymer inclusion membranes ( PIMs ) using Cyrene from PVC starting materials . 4 In a direct comparison with conventional petroleum-based solvents , the study found that bio-based solvents were a viable alternative for the production of PIMs , which are themselves a key green chemistry alternative to traditional solvent extraction methods . In addition , Cyrene has been shown to be an excellent solvent for the production of poly ( lactic-co-glycolic acid ) nanoparticles for drug delivery systems . 5 Researchers at Friedrich Schiller University in Jena , Germany , found that using Cyrene resulted in the production of high-purity nanoparticles ; Cyrene itself and the nanoparticles produced in the solvent were found to be biocompatible using the hen ’ s egg test . These results have the potential to open up a number of key areas where Cyrene has significant advantages over traditional solvents in both performance and safety , including drug delivery systems and medical implants .
Battery reclamation
Circa is part of the R2LIB ( Reclamation , Remanufacture of Li- Ion Batteries ) project , funded by UK Research & Innovation through the Faraday Battery Challenge . R2LIB is focused on developing cost-effective , high-performance and recyclable
automotive batteries and aims to develop the first UK industrial scale capability to reclaim and reuse the most valuable components of end-oflife electrical vehicle batteries . Cyrene is specifically being used to recover PVDF , a high-performance , high molecular weight polymer that is widely used as a binder in Li-ion battery cathodes . PVDF processing currently relies on NMP , as few alternatives have been able to dissolve PVDF . Early results looking at recovery from spent electrodes have indicated Cyrene ’ s unique properties are useful in separating PVDF from other black mass materials . Separately , research from Oak Ridge National Laboratories in the US has shown that sustainable recycling of cathode scraps from spent Liion batteries can be achieved via a Cyrene-based separation procedure . 6 They investigated a closed-loop
26 SPECIALITY CHEMICALS MAGAZINE ESTABLISHED 1981