Debromination of hexabromobenzene by its co-grinding with CaO.
Chemosphere
; 48(8): 787-93, 2002 Sep.
Article
em En
| MEDLINE
| ID: mdl-12222772
ABSTRACT
A hexabromobenzene (HBB, C6Br6) powder was subjected to co-grinding with excess CaO powder in air using a planetary ball mill to investigate mechanochemical debromination of the HBB sample. The reaction proceeds smoothly with an increase in both grinding time and molar ratio of CaO addition. The co-grinding enables us to debrominate HBB, forming CaBr2, C and CaCO3 besides excess CaO in the product. CaBr2 in the product tends to absorb moisture from the atmosphere to form CaBr2 x nH2O. The reaction yield is quantitatively evaluated by measuring the amount of water-soluble bromide through water washing and the amount of unreacted HBB through toluene washing. It is found that almost 100% of debromination is achieved by 6 h grinding with the molar ratio kept constant at 21. Radicals are detected in the ground products, possibly due to rupture in the covalent bonds of C-C and C-Br in HBB.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bromo
/
Bromobenzenos
/
Retardadores de Chama
Idioma:
En
Revista:
Chemosphere
Ano de publicação:
2002
Tipo de documento:
Article
País de afiliação:
Japão