These last few decades, membranes and monoliths have been increasingly used as stationary phases for chromatography. Their fast mass transfer is mainly based on convection, which leads to reduced diffusion, which is usually observed in resins. Nevertheless, poor flow distribution, which causes inefficient binding, remains a major challenge for the development of both membrane and monolith devices. Moreover, the comparison of membranes and monoliths for biomolecule separation has been very poorly investigated. In this paper, the separation of two proteins, bovine serum albumin (BSA) and lactoferrin (LF), with similar sizes, but different isoelectric points, was investigated at a pH of 6.0 with a BSA-LF concentration ratio of 2/1 (2.00 mg·mL −1 BSA and 1.00 mg·mL −1 LF solution) using strong cation exchange membranes and monoliths packed in the same housing, as well as commercialized devices. The feeding flow rate was operated at 12.0 bed volume (BV)/min for all devices. Afterward, bound LF was eluted using a phosphate-buffered saline solution with 2.00 M NaCl. Using membranes in a CIM housing from BIA Separations (Slovenia) with porous frits before and after the membrane bed, higher binding capacities, sharper breakthrough curves, as well as sharper and more symmetric elution peaks were obtained. The monolith and commercialized membrane devices showed lower LF binding capacity and broadened and non-symmetric elution peaks.

In recent years, many biocatalytic processes have been developed for the production of chemicals and pharmaceuticals. In this context, enzyme immobilization methods have attracted attention for their advantages, such as continuous production and increased stability. Here, enzyme immobilization methods and a collection of nitrilases from biodiversity for the conversion of 3‐cyanopyridine to nicotinic acid were screened. Substrate conversion over 10 conversion cycles was monitored to optimize the process. The best immobilization conditions were found with cross‐linking using glutaraldehyde to modify the PMMA beads. This method showed good activity over 10 cycles in a batch reactor at 30 and 40°C. Finally, production with a new thermostable nitrilase was examined in a continuous packed bed reactor, showing very high stability of the biocatalytic process at a flow rate of 0.12 ml min–1 and a temperature of 50°C. The complete conversion of 3‐cyanopyridine was obtained over 30 days of operation. Future steps will concern reactor scale‐up to increase the production rate with reasonable pressure drops.