Studies in surface chemistry of carbon blacks Part IV. Interaction of carbon blacks with gaseous chlorine

✍ Scribed by Balwant Rai Puri; R.C. Bansal

• Publisher: Elsevier Science
• Year: 1967
• Tongue: English
• Weight: 471 KB
• Volume: 5
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(67)90073-5

✦ Synopsis

The chlorination of carbon blacks at the optimum temperature of 450" results in fixation of chlorine and formation of hydrogen chloride, the amount depending to some extent, upon the hydrogen content. A part of the chlorine appears to be fixed by addition at the unsaturated sites and the rest by substitution of associated hydrogen. The carbon-chlorine complex is highly stable and only a fraction of the combined chlorine passes into solution as chloride ion on treatment with boiling concentrated sodium hydroxide. The complex decomposes evolving hydrogen chtoride on evacuation at 1200" but even then the entire amount of chlorine may not be eliminated. However, treatment in a current of hydrogen at 800" results in almost complete elimination of the chlorine. The fixation of chlorine causes appreciable alterations in the water adsorption isotherms indicating alterations in pore structure but there appears to be no chemical or auasi-chemical interaction with the chlorinated surface. The heat of immersion in water increases to a small extent after chlorination.