Читать книгу High-Performance Materials from Bio-based Feedstocks - Группа авторов - Страница 27

Carbon materials are one of many constituent substances on Earth. Their structures depend on the raw materials, processes, and preparation conditions. The biomass resources that are transformed into carbon materials for their use in catalytic applications are discussed in this section.

Biomass is a natural material grown by solar energy and comprises the world’s natural resources such as plants, animals, vegetables, and animal waste or organic waste. Biomass can be classified into two main types as illustrated in Figure 2.2. First, lignocellulosic materials are found in wood from natural forests and agricultural residues. The chemical compositions of general lignocellulosic materials are displayed in Table 2.1. These structures are primarily derived from carbon (C), hydrogen (H), and oxygen (O) atoms. The proper thermal processes can convert lignocellulose into carbon‐based materials that possess strong structures, which are suitable as a catalyst or catalyst support. Lignin is the hardest fraction in biomass and requires a high temperature for destruction. Second, non‐lignocellulosic materials, which can be obtained from algae, animal manure, sewage sludge, and others, contain a distinct proportion of proteins and lipids instead of lignocellulose. The non‐lignocellulosic carbon material generally has low strength and a nonrigid structure. According to the literature review, carbon‐based materials can be derived from several methods depending on the applications. In catalysis, the carbon material can play two roles, namely as a catalyst and as catalyst support. The required strength and rigidity under various reaction conditions mean that such carbon materials are typically obtained from lignocellulosic biomass resources rather than non‐lignocellulosic ones.