Catalytic Effect of Transition Metals (Copper, Iron, and Nickel) on the Foaming and Properties of Sugar-Based Carbon Foams

Abstract

Recently, bio-based carbon foams have gained much interest in many chemical industry fields because of their unique structure and properties. This study provides new information on the effects of catalytic metals (iron, nickel, and copper) on the foaming process. Specifically, the effects of these catalysts on the density, foam growth, and cell size and then further on the pore size distribution and specific surface areas after the physical activation are considered. Furthermore, some of the activated sugar foams were used in adsorption tests using methylene blue as adsorbent. Results showed that the highest effect on foam density was obtained using the iron catalyst in the foaming process. In addition, increasing the iron amount, the development of micro-pores decreased from 95.2 to 60.3% after cabonization and activation of the foams. Nickel and iron had the highest and lowest effect on foam rise at 1375 and 500%, respectively. Interestingly, when the nickel catalyst was used, cell sizes and surface areas two times larger than those when the foams were prepared with the iron and copper catalysts was obtained. The specific surface area of activated sugar-based carbon foams changed significantly with the increased copper amount inside the foaming solution in compared with iron or nickel catalyst. Methylene blue adsorption capacity of additional series of activated sugar foams decreased from 28 to 9% when meso-pore amount decreased.