The effect of oxidation on the physical activation of pitch: Crystal structure of carbonized pitch and textural properties of activated carbon after pitch oxidation

• Published in: Materials chemistry and physics Vol. 267; p. 124591
• Main Authors: Kim, Min Il, Seo, Sang Wan, Kwak, Cheol Hwan, Cho, Jong Hoon, Im, Ji Sun
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 15.07.2021; Elsevier BV
• Subjects: Activated carbon; Carbonization; Crystal defects; Crystal structure; Functional groups; Oxidation; Oxygen; Physical activation; Pitch; Specific surface; Surface area; Thermal oxidation; Pitch; Physical activation; Activated carbon; Thermal oxidation
• ISSN: 0254-0584; 1879-3312
• DOI: 10.1016/j.matchemphys.2021.124591

The effect of oxidation on carbonization and physical activation of pitch was determined for synthesis of activated carbon (AC). The prepared AC from non-oxidized pitch exhibited a low specific surface area of 0.2 m2/g. On the other hand, the specific surface area of prepared AC from the oxidized pitch increased up to 729.6 m2/g even by same activation process. The introduced oxygen functional groups were almost removed during carbonization (with only 3.1% or less oxygen remaining); therefore, they did not directly affect the activation process. However, introduced oxygen functional groups prevented the rearrangement of the pitch molecules during carbonization. This effect decreased the crystallinity of the carbonized pitch and increased the number of defects present. The defects acted as active sites and improved the pore structure; thus, AC with a high specific surface area was prepared. •The thermal oxidation of pitch for activation process.•The created defects on carbonized pitch by thermal oxidation.•The developed pore structure of activated carbon by defects.