Three kinds of particles with different hydrophilic and hydrophobic properties were used as fluidized particles of Fluidized Bed Medium Separation (FBMS). Minimum fluidization velocity, apparent specific gravity of fluidized bed and floating-sinking behaviors of dry and wet coals were measured in order to investigate the stability of fluidization by changing relative humidity of air flow introduced from the bottom of the fluidized bed. The fluidization of hydrophilic particles became unstable with increasing the relative humidity, because particle aggregation took place at a high humidity. On the other hand, the fluidization of highly hydrophobic particles was stable with wet coals even at a high humidity. Therefore, the FBMS with highly hydrophobic particles is applicable to the density separation of coals at a high relative humidity without a control device for the relative humidity.

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Fluidized bed medium separation (FBMS) was applied to the gravity separation of mortar and gravel for the recycle of waste concrete. Zircon sand (Z. S.)/glass beads (G. B.) and zircon sand/steel shots (S. S.) mixtures with various volume mixing ratios were employed as fluidized particles. Apparent specific gravity and the dispersion of a cylindrical fluidized bed were adjusted to 2.1-2.7 and less than 0.1 respectively by changing the volume mixing ratio of fluidized particles and the superficial velocity and then the mortar and gravel were loaded into the bed. As a result, the mortar and gravel were completely separated at the conditions that the volume mixing ratio was G. B.:Z. S.:S. S.=0:100:0 at the ratio of superficial velocity to the minimum fluidization velocity, u₀/u_mf=2.0, for the fluidized time of 10min. Furthermore, half batch type pilot-scale FBMS device (Gravity separation system with a new device that can discharge floating and sinking objects) was developed. Recoveries of mortar and gravel were investigated by floating-sinking experiments with the device. The recoveries of mortar and gravel were nearly 100% and 95%, respectively. High rate of recoveries was attained in with the FBMS using the new device.

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In order to establish a method for evaluating the particle retention performance of a ceramic membrane, microfiltration of suspensions of submicron polystyrene latex is performed, and the time changes in filtration rate, the particle rejection and the particle retention rate are evaluated. The rejection at the filtrate volume of 100cm per unit membrane area, R₁₀₀, is plotted against the ratio of particle diameter to pore diameter, d_p/d_m, for various membranes and particles. The plots clearly demonstrate that the transition to almost complete particle rejection from partial particle transmission through the membrane occurs at d_p/d_m of about 0.1. Furthermore, the filtrate volume at which the rejection reaches 0.9, v_0.9, is found to be one of the criteria for the evaluation of particle retention performance. This paper also proposes a method to evaluate the properties of filter cake formed on the membrane.

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Cathode materials for lithium ion battery were successfully prepared by both sol-gel such as polymerized complex method and aerosol process. Sol-gel process offered the precursor with high chemical homogeneity and crystallinity. The electrochemical properties of cathode materials such as capacity and cycle performance were improved. Aerosol process also offered spherical fine particles which had submicron size with narrow size distribution and had a porous microstructure. Both charge/discharge capacity and cycle performance of cathode materials powders obtained from aerosol process was superior to that of commercial cathode powders produced by solid state reaction. Large scale aerosol process was developed for industrial production of cathode materials and spinel type lithium manganate powders were produced. Manganese type lithium ion battery module for electric bicycle and tram was also developed and showed high performance compared with commercial battery.

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