The helical cell design for process intensification in centrifugal partition chromatography

Abstract

Centrifugal partition chromatography (CPC) is a liquid–liquid chromatography technique commonly used to separate natural products. Since increasing the CPC separation performance by operational conditions is limited, process intensification in CPC requires optimizing the CPC cell design. This study aims to experimentally investigate the performance of a miniLili CPC device with a novel helical cell design developed by LiliChro (Hungary) and compare it to conventional CPC cell designs. The miniLili CPC device has 80 cells and a volume of 36 mL. Performance is evaluated based on stationary phase retention, number of theoretical plates, and separation resolution. Additionally, “capacity utilization”, defined as a product of stationary phase retention and the cells’ efficiency, is introduced as a new metric to compare the overall performance of CPC devices of different volumes, cell numbers, and cell geometry. Experiments are performed using the Arizona N solvent system and methyl, ethyl, and propyl parabens as solutes. The novel cell design demonstrates high stationary phase retention of 0.9-0.95 at rotational speeds of 1000-1500 rpm and volume flow rates of 1-5 mL/min. Although the resolution in the miniLili CPC device is comparatively lower than that of conventional CPC devices, higher resolutions can be reached by increasing the rotational speed, flow rate, or number of physical cells. Despite this, the capacity utilization of the miniLili CPC device exceeds that of conventional designs within its operating flow rate range. These findings underscore the potential of advanced cell geometries to drive process intensification in CPC, marking a significant step forward in the evolution of high-efficiency CPC.