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Droplets having high uniformity m d a widely controllable size range (from mm to pm) were obtained Iby means of electrostatic dispersion in an oil-in-water system, as reported previously by the authors. In liquid-in-gas systems, manly studies reported that the electrostatic force acting on the liquiid due to the surface charge seemed to be the main factor affecting the atomization. However, using distilled water as a coittinuousphase liquid causes the theoretical analysis to be very difficult because distilled water has high conductivity and permittivity. Therefore, in the present study, experimental work is carried out on dispersion mechanisms in an oil-in-water system. The main factor affecting the atomization is considered to be electrohydrodynamic flow of continuous-phase liquid (distilled water) around the capillary nozzle tip. The repulsiive force between the nozzle tip and the charged liquid meniscus is also considered to have a small effect. The amount of electric charge on the dispersed-phase liquid (kerosene) is considered to be negligible because of the very short relaxation time of the surrounding continuous-phase liquid. It is suggested that the droplet size and frequency distribution can be controlled by adjusting the operating conditions (applied voltage) anid design parameters (nozzle shape). I. bJl"T0DUCTIONFine particles are used widely in industry and in many laboratories. In recent advanced technologies, there is a need for the particles to be more uniform and have a widely controllable size range. The electrostatic method is superior to the other atomization methods for satisfying the above requirements. However, the electrostatic method is limited to a narrow range of physical properties of the dispersed liquid (such as electrical conductivity and viscosity).Many investigations of electrostatic atomization have been conducted in liquid-in-gas or water-in-oil systems. Conversely, the opposite system (such as gas-inwater or oil-in-water) has been considered to be impossible to atomize by electrostatic means [ 11. However the present authors have reported that a highly insulating liquid (without the addition of surface active agents) or gas was atomized in a distilled water medium by modification of the nozzle shape [2 -111.The characteristics of liquid droplets formed in liquid media (oil-in-water system in this case) by the electrostatic method are as follows: (1) droplets having high uniformity are controllable over a wide size range, (2) applied voltage is not high (hundreds to thousands of volts), (3) electrically insulating and/or viscous liquids can be dispersed, (4) very fine droplets do not fly away along with the air flow, and it is easy to collect them, (5) some kinds of plastic monomer (styrene, acrylic resin, etc.) which are dispersed in water can be easily polymerized to make solid plastic beads, (6) a fine emulsion (with or without additives) is formed which enhances liquid-liquid extraction.A study of the atomization mechanisms of the present technique is very important when one...

A new effective method for fabricating adsorbents using woody biomass in order to reduce bio-waste must be developed. This paper discusses the chemical treatment of woody biomass and reports a new adsorbent with high metal adsorption ability. This adsorbent was prepared by performing three treatments. The first was potassium loading onto woody biomass through impregnation using a potassium carbonate solution. The second was heat treatment at 250 °C to increase the number of metal-capturing groups. The third was nitric acid treatment to remove potassium species. The metal adsorption ability of the resulting adsorbent, measured as the nickel loading, was as high as approximately 8.3 wt%. This adsorbent was heated at 600 °C after nickel loading and it was found that the nickel particles were approximately 3.5 nm in size and highly dispersed in the char. This indicated that the nickel-loaded char had potential to show high activity for biomass tar reforming.

This study focused on the development of an effective Ni-loaded catalyst using woody biomass for tar decomposition. Microwave irradiation was utilized to heat biomass for catalyst preparation. The amount of Ni adsorbed on biomass was 9.0 wt%. Thermal treatment of the nickel-loaded biomass at 600 °C resulted in a fine dispersion of nickel particles with a diameter of approximately 4.5 nm. The catalytic activity of the prepared catalyst for the decomposition of biomass tar derived from Japanese cypress was investigated in a two-stage fixedbed reactor. The nickel-loaded char showed high activity for tar decomposition at a relatively low temperature of 600 °C. The yields of H2, CO, and total gas obtained with the nickel-loaded char were approximately 5.2, 2.8, and 3.5, respectively, times higher than those obtained without a catalyst.