Masahiro Shimada

The Properties of Activated Carbon Made from Waste Newsprint Paper

Activated carbon is a porous material made by activation of carbon materials, such as coal, by steam or carbon dioxide gas to form numerous micropores on the surface which gives the material high adsorption characteristics and it is widely used as a purifier for water and air. In this research, to develop a new use for waste paper, activated carbon was prepared from waste newsprint paper and its adsorption characteristics were measured. As a result, activated carbon with an iodine adsorption capacity of 1310 mg/g, a methylene blue adsorption capacity of 326 mg/g and a specific surface area of 1000 m2/g was obtained. These adsorption capacities were almost the same as ordinary activated carbon on the market.

Electromagnetic Shielding Properties of Woodceramics Made from Wastepaper

Woodceramics are new porous carbon materials, which are made by impregnating woody materials with phenol resin and then thermoformed in a vacuum furnace and these have been shown to have electromagnetic shielding properties. In the recycling of wastepaper, ways of using the wastepaper other than for paper pulp are needed to be developed. In this study, we made Woodceramics from handbill advertisement paper and telephone directory paper, and measured their electromagnetic shielding properties in order to find new uses for wastepaper. The results showed that the Woodceramics made from wastepaper had an electric shielding effectiveness of 30 dB for 100 MHz and 40 to 43 dB for 300 MHz or higher, and had a magnetic shielding effectiveness of 30 dB for 100 MHz and 37 dB for about 400 MHz. An electric equivalent circuit of the pore model in the Woodceramics is introduced. In addition, it is proposed that the excellent electromagnetic shielding effectiveness of the Woodceramics is caused by dielectric loss.