Abstract
The present work focuses on the application of ceramic membrane filtration to rose-processing wastewater treatment and polyphenols recovery. Filtration was performed in two successive steps: microfiltration, using 150 kDa ceramic membranes to remove all suspended solids, followed by ultrafiltration with 15 kDa membranes or nanofiltration with 1 kDa membranes for further dissolved compound treatment and polyphenol recovery. The rejection rates and recovery amounts of polyphenols like catechin, chlorogenic acid, gallic acid, kaempferol, and quercetin were determined with all three membranes. The results showed that ultrafiltration and nanofiltration exhibited significantly higher polyphenol rejection rates compared to microfiltration. Gallic acid demonstrated the highest recoveries with all tested membranes, which indicated its great affinity toward the active layer of the ceramic membrane. All the other polyphenols exhibited recoveries ranging from moderate to low with all three membranes. Ethanol was used for the desorption of polyphenols adsorbed on the membrane surface. This work highlights the potential of ceramic membrane filtration as an efficient method for polyphenol recovery from rose-processing wastewater, which would provide sustainable solutions for both wastewater treatment and resource recovery in rose oil production.