In this work we report the first investigations on the dissolution of bulk PA 6 in CEW. We conclude that our experimental approach is suitable to dissolve not only textile fibers but also large filaments of PA 6 in CEW. Further we conclude that energy supply with ultrasound is more effective than energy supply with microwaves improving the yield of dissolved and recovered PA 6 after 5 hours from 31 to 52%. Furthermore, our investigations show that the H 2 O:EtOH molar ratio is crucial for the dissolution efficiency of PA 6. CEW:PA ratios > 5 seem to be necessary to promote swift dissolution in an excess of solvent. Overall, we could show that the yield of recovered PA 6 using CEW after 3 hours of bulk dissolution was increased from 18 to 69% by changing the energy supply mode from microwaves to ultrasound and the composition from CEW C to E whilst maintaining a CEW:PA mass ratio of 8.5.