A Low-Cost Pressure Driven Filtration System for Nanofiltration Membrane Evaluation

With the growing interest in fabricating nanofiltration membranes using novel materials and techniques, there is an increasing need to evaluate the practical viability of innovative membranes at the early stages of development. In many materials research laboratories, the access to professionally manufactured membrane evaluation systems may be limited. Here, we present a pressure driven filtration system design for evaluation of nanofiltration membranes, that can be constructed from 3D-printed parts and widely available off-the-shelf components at a cost of approximately 60 €. The system uses a stirred cross-flow design capable of circulating the feed solution at the membrane surface and maintaining a stable feed concentration over extended filtration experiments—like conventional cross flow cells. It is suitable for filtration of aqueous solutions containing dyes, inorganic salts and dilute acids. Validation was performed by filtering a 2000 mg L−1MgSO4 solution through a Veolia RL membrane at 7.6 bar, achieving a 96.5% rejection rate and a permeance of 7.5 L m−2 h−1 bar−1 after 24 hours of continuous operation.