Process Intensification via Continuous and Simultaneous Isolation of Antioxidants: An Upcycling Approach for Olive Leaf Waste

The isolation of individual pharmaceutical-grade bioactive compounds from complex plant extracts is still a sustainability challenge. Process intensification improves manufacturing design to achieve significant benefits in process efficiency and operation, product quality, and waste management. A process optimization and intensification methodology for the simultaneous isolation of biophenols from agricultural waste, using imprinted materials and nanofiltration membranes, is reported herein. First, temperature-swing molecular imprinting technology was used to selectively extract individual biophenols from olive leaf extracts. Second, solvent-resistant nanofiltration was used to “in-line” concentrate the product and waste streams as well as to recover the solvent. The predictive mathematical models for the adsorption dynamics and the membrane separation resulted in a significant reduction of the carbon footprint, E factor, and economic sustainability. This process was designed for easy operation with multiway valves to aid safety and reduce operating costs. The presented process intensification methodology can be generally adapted for waste upcycling through sustainable isolation of multiple high-value products from complex mixtures.