| 摘要 |
<p>1,214,861. Graphite. BRITISH PETROLEUM CO. Ltd. 18 Feb., 1969 [29 Feb., 1968], No. 9818/68. Heading ClA. [Also in Division C5] A graphite powder having a heat of adsorption of n-dotriacontane from n-heptane of at least 0.5 cals/gm., is prepared by grinding graphite in a grinding fluid which comprises water and an organic water-soluble additive containing a hydrocarbon group having at least 6 carbon atoms. Suitable organic water-soluble additives are long chain fatty acids and esters, long chain alkyl substituted sulphonates and quaternary ammonium compounds having at least one C 6 or higher alkyl group attached to the nitrogen atom with the anionic part of the quaternary ammonium compound being any suitable acid radical such as chloride, orthophosphate or sulphate. The grinding is preferably carried out in a vibratory ball mill below the surface of the grinding fluid which optionally contains an anti-corrosion additive e.g. sodium nitrite. The graphite of the invention may be used to form lubricating compositions.</p> |
