| 摘要 |
The ageing stability of mineral oils is improved by the addition of at least 0.5% by weight of an aromatic fraction produced in accordance with Specifications 958,859 or 993,927. The aromatic fraction may first be subjected to a catalytic conversion in the presence of hydrogen and a catalyst at 10-30 atmospheres gauge and 400-450 DEG C. Catalysts specified are cobalt and molybdenum oxides on alumina, cobalt, molybdenum and iron oxides on alumina and tungsten disulphide and nickel sulphide. Transformer oils are specified as the base oils. |
