The ecological impact of membrane-based extraction of phenolic compounds a life cycle assessment study

摘要

Many phenolic compounds show high boiling points, low molecular weights, moderate polaritiesnor high toxicities. Therefore, conventional wastewater treatment is limited or expensive.nRecycling of the separated compounds is often not possible. But, if liquid-liquid reactivenextraction is linked to a non-porous membrane, some or all of the above mentioned limitationsnmay be overcome. The key element is a composite membrane with a dense, hydrophobic topnlayer which avoids the mixing of the two aqueous fluid streams. The dilute phenol stream isnone of them, the other is caustic soda as stripping solvent. Since the basics of this technologynhave been discussed before, the scope of this study is to facilitate process implementationnand integration. To this end, a life cycle assessment framework is used to identify the optimalnequipment size for the treatment of wastewater that may, for example, originate fromnthe production of polycarbonate. Limiting for this application is not the environmentalnperformance though, but most likely process economics.