Lignocellulosic materials are economically cheap, perfect precursors to produce activated carbon. Due to the abundance of cellulosic biomass in the nature they are usually used to produce activated carbon as the catalytic active site in these cata­lysts are chemically bound, as a result both the biodiesel and glycerol by-product will be free of catalysts contaminants (Emrani and Shahbazi 2012). For biomass derived CBSC, the body is often amorphous and owns aromatic structure. Moreover, conventional solid acids bearing single functional groups are different from the biomass derived CBSC. CBSC possess high density of nearly neutral phenolic — OH in addition to Brpnsted acid sites (-SO3H and — COOH), as shown in Fig. 15.4 (Kang et al. 2013).

Carbonised Material (AC)

/ CO I O» CO

: о : о л; o)o r MX ‘ О “

-г ‘ о

Pyrolysis Carbonisation Sulfonation SO3H-Carbon(Catalyst)

Fig. 15.5 Preparation of SOaH-carbon (Konwar et al. 2014, with permission)