6533b827fe1ef96bd12859a2

RESEARCH PRODUCT

Mass transfer in nonisothermal ferrocolloids under the effect of a magnetic field

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Abstract The paper presents a review of newest experimental results on particle thermal diffusion in hydrocarbon based ferrofluids. The measurements are performed using a vertical thermal diffusion column, the Soret coefficient is evaluated from particle separation curves employing a simple column theory which accounts for thermal convection in the vertical channel forced by a concentration buoyancy force arising during the thermophoretic transfer of heavy particles. High positive values of the Soret coefficient of lyophilized Fe 3 O 4 and Mn x Zn 1− x Fe 2 O 4 particles in surfacted tetradecane based colloids are measured. Experiments confirm the theoretically predicted anisotropy of particle thermophoretic mobility in the presence of a uniform magnetic field oriented parallel or perpendicular to the temperature gradient.