| 摘要 |
<p>A mixture of brominated aromatic hydrocarbons is produced by a two-stage process involving reacting an aromatic hydrocarbon and bromine in a first stage to give a penta-bromo derivative, and then, in the presence of the first stage product, reacting a further quantity of aromatic hydrocarbon and bromine to give tri-bromo derivative or a mixture of di- and tri-bromo derivatives with the latter predominating. The mixture may have 40-95 mole per cent of tri- or di- and tri-bromo derivatives, and 40-5 mole per cent of penta-bromo derivative with not more than 2 mole per cent of tetra-bromo derivatives. The mixture is suitable as a well bore fluid, and can be varied in composition to give products with a range of specific gravities for that purpose. The substantial absence of tetra-bromo derivatives means that the products can be used without toxicological problems.</p> |
