Preparation of microporous carbon–ceramic cellular monoliths

✍ Scribed by T Valdés-Solı́s; G Marbán; A.B Fuertes

• Book ID: 104430309
• Publisher: Elsevier Science
• Year: 2001
• Tongue: English
• Weight: 761 KB
• Volume: 43
• Category: Article
• ISSN: 1387-1811
• DOI: 10.1016/s1387-1811(00)00354-1

✦ Synopsis

Carbon±ceramic cellular monoliths were prepared by coating a ceramic cellular monolith with a polymeric solution (carbon precursor). Phenolic (resol and novolac) or furanic resins, and polysaccharides (sucrose and dextrose) were used as carbon precursors. The following procedure was adopted: (a) substrate impregnation with a polymeric solution, (b) curing or drying, (c) carbonisation (700±1000°C, N 2 ), and (d) physical (H 2 O, 700°C) or chemical (ZnCl 2 ) activation. In optimal conditions (e.g. phenolic novolac, 64 wt.%; two impregnation±curing±carbonisation cycles) the material obtained exhibited a high carbon percentage ($14 wt.%) with a micropore volume and a speci®c surface area (relative to the mass of deposited carbon) of 0.32 cm 3 g À1 and 427 m 2 g À1 , respectively. By physical activation (burno: 20 wt.%) the micropore volume increased to 0.44 cm 3 g À1 and the speci®c surface area to 1450 m 2 g À1 . By means of chemical activation, a high carbon load ($13 wt.%) was obtained in a single step, with a micropore volume of 0.36 cm 3 g À1 and a speci®c surface area of 791 m 2 g À1 . The activated material shows a uniform carbon distribution, good adsorption properties, good electrical conductivity (1.15 X À1 cm À1 ) and a high mechanical strength (16 MPa).