We produced porous carbon from the used paper available as a plant basis. Plants can grow on the carbon, because it has a great deal of pore. So we studied how the pores are generated in process of carbonization. The pores are very important to growth of the plants. The pores are also very influential to handling strength of the carbon. Therefore we investigated the relation between strength and the pore or density. In addition, the carbonization process was examined from the standpoint of volatilization.

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The use of charcoal board produced by binding charcoal powder as a countermeasure against “Indoor Air Pollution” and the removal capability of the charcoal board for harmful gases were examined. The charcoal board produced from charcoal carbonized at 500°C removed ammonia and formaldehyde very well, and that made at 900°C removed benzene, toluene and formaldehyde very well. The charcoal board mixed the charcoal carbonized at 500°C and that at 900°C sufficiently removed all gases. Furthermore, the charcoal board showed the satisfactory removal effect in a model test room, too. The charcoal board can decrease indoor pollutants and may provide a good environment for patients, such as “Sick Building Syndrome” and “Chemical Sensitivity”. It is expected that the problem of indoor air pollution is solved by using the charcoal board.

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Carbonization behavior of the acrylic cation exchange resin with zinc ion was investigated as a function of the introduced amount of zinc ion, carbonization temperature (773-1073K) and the atmospheric gas (CO₂, H₂, N₂) during the carbonization. The carbonization of the resin that occurs along with liquefaction of the resin in the absence of zinc shifted to solid phase carbonization according on the increase of introduced zinc ion. The resins carbonized in CO₂ and H₂ with small zinc content produced the irregular shaped carbon with glassy surface and dispersed zinc oxide but with small specific surface area and pore volume. The resin carbonized in CO₂ with large zinc content resulted in the macro porous carbon keeping the initial shape and inner morphology of the precursor resin. The samples carbonized with small zinc content showed small H₂ adsorption capacity with very small specific surface areas measured by nitrogen adsorption at 77K. The samples carbonized with high zinc content showed the large specific surface area and their H₂ adsorption capacity was high in the sample with high specific surface area.

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The present paper reviews carbonization and activation techniques for the production of carbonaceous adsorbents with the optimal properties for their intended purpose. The physical adsorption ability of the adsorbent increases with increase in specific surface area and with decrease in mean pore diameter. The chemical adsorption properties of the adsorbent are affected by surface functional groups such as carboxyl and phenolic hydroxyl, which influence the adsorption behavior of ionic compounds by dissociating into ions in aqueous solution. Regarding carbonization techniques, the paper discusses the pore-size distribution of charcoals prepared from various types of wood, the effect of carbonization temperature and gas atmosphere on the physical adsorption properties and on the surface functional groups of charcoal, and the effect of raw material other than wood. Regarding activation techniques, the basic principle of the steam activation method and the effect of activation conditions on pore-size distribution are discussed. In addition, the characteristics of the new air activation method are described. Regarding chemical activation, an outline is given of the characteristics of the alkali activation method, which produces activated carbon with high surface area.

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For the purpose of designing a new automobile-body composite material with light-weight and extremely high mechanical strength, the knowledge-systematization technique was employed. Single-wall carbon nanotube is ideally suited as a guest material for the composite in terms of weight and mechanical strength. The basic procedure of the technique is composed of obtaining relationships among plausible mechanism for emerging the properties and functions, processing conditions for fabrication and the characteristics and functions of resulting material. The employment of the technique provides us with information relating to the fundamental structure of material as well as key points which must be considered to attain the goal of the development.

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