The Effect of Alternative Magnetic Field on the Pigment Ejection from Magnetic Anisotropic Gel Beads

Abstract

Abstract Magnetic anisotropic gel beads (MA gel beads) were prepared by the gelation of a ferrite suspension in a static magnetic field. MA gel beads were found to oscillate in an alternating magnetic field. This oscillation can possibly reduce the thickness of the diffusion layer on the interface between the gel beads and the surrounding solution, so that the substance can be transferred more quickly across the gel–liquid interface. MA gel beads consisted of alginate gel containing ferrite powder and toluidine blue as a pigment. MA gel beads were loaded into a dual glass tube to make a column bed, which was inserted into a coreless coil which produced the alternating magnetic field. The concentration change of the pigment in the effluent from the column was measured during a lapse in time with repeating off and on the input of the alternating magnetic field. The pigment concentration in the effluent upon exposure to the alternating magnetic field increased to twice the maximum value obtained without a magnetic field. The stronger was the static magnetic field at the time of gelation and the alternating magnetic field, the larger was the increase in pigment concentration in the effluent. Also, the higher was the concentration of ferrite in gel beads, the larger was the increase in pigment concentration in the effluent.