Abstract

Continuous Efficient Multistage Extraction

Andrea Adamo, Chief Executive Officer, Zaiput Flow Technologies

Liquid-liquid extraction is a very common workup strategy in pharmaceutical production due to its high selectivity and large capacity at relatively small energy consumption. In many cases, multiple extraction stages are required to achieve a high degree of separation. Current industrial approaches have the disadvantages of excessively large footprint, limited flow capacity and, importantly, are difficult to scale-up. In this work, we present multistage countercurrent liquid-liquid extraction at the ml/min scale. The set up is essentially composed by a cascade of extraction steps; at each extraction step two immiscible phases are first contacted for mass transfer and then separated with membrane based liquid –liquid separators; after each stream proceeds to its subsequent extraction step. The overall set up allows quick to run multistage extraction experimentation, the low holdup volume is less than a few mL for each extraction step, making it suitable for lab-scale extraction and valuable/dangerous chemicals. The set-up can be used also for experimentation and optimization of extraction conditions especially for multicomponent or un-identified species were typically simulations aren’t adequately reliable. After providing background information, we’ll discuss system design and implementation, show benchmarking of our set up with respect to literature test systems, show a complex multicomponent example and discuss scalability.