Design of cone-and-plate test cell for ultrafiltration

In ultrafiltration (UF) processes, the mass transfer coefficient depends on the hydrodynamic shear at the membrane surface. Unfortunately, in all the existing UF test devices, shear stress is non-uniform and only an average value is used. This paper discusses the theory, design, fabrication, and experimental validation of a next-generation cone-and-plate test cell (CPTC) to carry out UF under uniform surface shear of 2 μ ω secθ1 Pascals (where μ is viscosity, ω is angular velocity, and θ1 is the half-angle of the cone). This next-generation test cell provides experimental data under uniform shear, which would enable better validation of mathematical models for UF processes. Work is in progress to study transient shear and shear-reversal effects using the CPTC, by controlling the angular velocity and direction of rotation of the cone using a computerised servo-motor control system.