Influence of sodium carbonate on coke reactivity

✍ Scribed by J.W. Patrick; F.H. Shaw

• Publisher: Elsevier Science
• Year: 1972
• Tongue: English
• Weight: 958 KB
• Volume: 51
• Category: Article
• ISSN: 0016-2361
• DOI: 10.1016/0016-2361(72)90042-7

✦ Synopsis

The objective of the investigation described was to establish the basic nature of the underlying processes involved in the catalytic activation of coke by the addition of sodium carbonate to coal before carbonization.

Cokes were made in laboratory carbonizations of a series of coals, representative of a range of coal rank, to which sodium carbonate was added in various quantities. The addition of sodium carbonate reduced the coke ignition temperature and the microstrength, altered the pore size distribution of the coke and reduced the fluid range of the coal, but it had little influence on the generation of unpaired electrons during carbonization and caused no change in the coke crystallite dimensions as determined by X-ray diffraction despite the retention in the coke of large proportions of sodium. The results lead to the conclusions that the presence of sodium carbonate alters the course of the carbonization process and leads to the production of a coke which contains chemically-combined sodium and which is of similar structure to but different texture from coke produced in the absence of sodium carbonate. The activation is considered to take place through an electronic mechanism and differences in the degree of activation obtained by addition of sodium carbonate to coals of different rank can be attributed to the state of oxidation of the coal.