Investigation of Mechanical, Chemical and Adsorptive Properties of Novel Silicon-Based Adsorbents with Activated Carbon Structure

Abstract

In this article, for the first time the chemical and mechanical properties of novel adsorbents based on the coating of activated carbons with silicon carbide are reported. The adsorbents are prepared by chemical vapor infiltration (CVI) of activated carbons with tetramethylsilane (TMS) as a precursor. A comparison of two different modified types of activated carbon, C40/4 Extra and A35/4 Extra, each infiltrated with 25%-mass at infiltration temperatures of 973.15 and 1098.15 K, respectively, is presented. Adsorption properties were characterized by measuring nitrogen isotherms and volatile organic compounds (VOC) isotherms in gas phase and excess isotherms in liquid phase. In addition, the physico-chemical properties including the bulk density, ash content, particle hardness, abrasion, conductivity, water-soluble components, and pH value were determined. Furthermore, the first experiments in a fluidized bed adsorber are presented. The results show that the adsorption properties of the modified adsorbents are mainly maintained. The particle hardness and the abrasion resistance increases with increasing infiltration temperature, which leads to an overall increasing of mechanical stability. A modification of the chemical stability as a result of the infiltration experiments is not observed.

Keywords

• abrasion
• activated carbon
• chemical vapor deposition (CVD)
• silicon carbide