One-step preparation of acicular magnetite

One-step method was adopted to prepare acicular magnetite under magnetic field.The major influencing factors on the composition of the product were investigated.The optimum process conditions were obtained.The influences of magnetic field on growth of particles were discussed.The results indicate that magnetic field has remarkable effect on the shape of magnetite.Magnetite particles change from spherical into acicular shape with the increasing of magnetic field strength.The higher the magnetic field strength is,the more acicular particles the product has.Under 0.35T magnetic field,shape transformation process of precipitate is from flocculent to hexagonal,then to granular,and finally to acicular particles.