| 摘要 |
<p>Method comprises incorporating in the added hydrocarbons after their prodn. a colourless reducing chromogenic substance, which developes a colour on contact with an oxidising agent. Also equipment for carrying out the test, consisting of a transparent tube contg. a layer of oxidising agent is claimed. Process is a simple, accurate, test requiring no special equipment or skill. A strong colour is developed, so that amt. of additive needed is small. A large sample can be drawn into the equipment, which is easily calibrated to show the amt. of cheaper blending agent present. In an example, 800 ml petrol is mixed with 200 ml benzene contg. 1 mg/l crystal violet lactone. Application of 6 drops to a TLC silica plate with drying of each produces a brilliant blue stain.</p> |
