Composition of candles

Now the main raw material of candles is paraffin, which is a mixture of several higher alkanes, mainly n-docosane and n-octacosane, which are obtained from the waxy fraction of petroleum by cold pressing or solvent dewaxing. The element is about 85%, and the hydrogen element is about 14%.

The added accessories include white oil, stearic acid, polyethylene, essence, etc. Among them, stearic acid is mainly used to improve the softness, and the specific addition depends on what kind of candles are produced.

When the candle burns, the products of the combustion of n-docosane and stearic acid are carbon dioxide and water. When the candle is lit, the flame that burns initially is small and gradually becomes larger, and the flame is divided into three layers (outer flame, inner flame, and flame core).

The flame core is mainly candle vapor, the temperature is the lowest, the inner flame paraffin is not fully burned, and the temperature is higher than the flame core, because there are some carbon particles, the flame is the brightest, the outer flame is fully contacted with the air, the combustion is sufficient, and the temperature is the highest. A matchstick is quickly flattened into the flame, and taken out after about 1 second, the part of the matchstick that touches the outer flame first turns black.