Surface characteristics and surface behaviour of polymer carbons—V: Interaction of polymer carbons with bromine in aqueous solutions

✍ Scribed by R.C. Bansal; T.L. Dhami; Sat Parkash

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 459 KB
• Volume: 18
• Category: Article
• ISSN: 0008-6223
• DOI: 10.1016/0008-6223(80)90030-5

✦ Synopsis

Interaction of poIymer charcoais with bromine in aqueous sofutions results in the conversion of bromine into HBr and its fixation by the charcoals. The amount of bromine converted into HBr is related to the surface acidity of the char while the amount fixed depends upon the nature of the char and the history of its formation. PVDC and Saran charcoals adsorb appreciably larger amounts of bromine than PF and UF charcoals prepared at the same temperature. The adsorption decreases on outgassing the chars at 1OOOC and the decrease is only slight in case of PVDC and Saran chars. The adsorption of bromine involves two different mechanisms. In case of the highly porous charcoals such as those of PVDC and Saran prepared by the carbonisation of oxygen free polymers, the adsorption of bromine occurs largely in pores. In the case of less porous charcoals such as those of PF and UF prepared by the carbonisation of oxygen containing polymers, the adsorption of bromine takes place partly by addition at the unsaturated sites and partly by substitution in place of bonded hydrogen.