Development of a continuous aqueous two-phase flotation process for the downstream processing of biotechnological products

Optimized Apparatus Design for Continuous Aqueous Two-Phase Flotation (ATPF)

“…Furthermore, a continuous ATPF was presented for the first time, which leads to a significant increase in space-time yield [23]. In this work it is found that most of the mass transfer occurs at the beginning of batch ATPF, when the concentration gradient between enriched bottom phase and unloaded top phase is highest.…”

“…Due to the different compositions of the phases, there is a density difference of 101 kg/m 3 , leading to the vertical separation of the two phases in the flotation apparatus. The selection of the material system is based on previous work [22,23].…”

“…When ATPF is operated in batch mode, a vertical flotation cell as known from conventional froth flotation is usually used. This allows integrating only one single gassing unit and disables a spatial separation of unloaded and loaded top phase in a continuous ATPF [23]. To overcome these disadvantages, an alternative apparatus design is needed.…”

“…This allows biomolecules to be selectively separated from complex biosuspensions and concentrated in a collecting top phase. Both pharmaceutical and technical molecules [1,[3][4][5][6][7][8][9] and enzymes [10][11][12][13][14][15][16][17][18][19][20][21][22][23] can be separated from plant extracts or fermentations with microalgae, bacteria or fungi. In a review Lee et al [2] summarized the research on ATPF and justified the great potential in direct recovery of biotechnological products by ATPF.…”

“…To take advantage of this effect, continuous phase exchange was implemented. However, it was found during the studies that the vertical flotation columns used for batch ATPF and known from froth flotation are disadvantageous in continuous operation of the process, since there is no spatial separation between unloaded and loaded top phase and thus no selective exchange is possible [23].…”