Preparation of porous ceramic materials dispersed with activated carbon from industrial solid wastes and their characterization

Abstract

In order to solve environmental problems, such as the shortage of dump yards and the exhaust of toxic gases by incineration of the industrial solid wastes (ISW), the development of a new method to prepare porous adsorbents from ISW's was investigated. Sludge from gravel plants and sawdust from wood plants were used as ISW'. A mixture of the sludge, sawdust, and clay minerals added as caking additive was kneaded together with an appropriate amount of waster or activator aqueous solution. The kneaded mixture was molded in a cylindrical shape by extrusion, and then calcined for 1 h under N2 atmosphere. The prepared calcined bodies had a porous structure with pore sizes of micron order. It was found by the methylene blue adsorption measurement in aqueous media that relatively high adsorption capacity (ca. 70 mg/g) was attained in case of the carbon-ceramics porous composite, which was calcined at 850°C with 14.5 mequiv./g-sawdust of K2CO3 as activator and potter's clay as caking additive. These results indicate that porous ceramic materials dispersed with activated carbon can be prepared from ISW, and an appropriate amount of activator and caking additive with low cation exchangeable ability are effective to enhance the adsorbability for methylene blue.