Petrol in sunlight

[AHPP]

Does petrol go this funny colour if left in strong sunlight for a week or has my butler mixed something with it? 

[AHPP]

[AHPP]

Definite brown twinge. Helpfully photo shows none of it. 

[GarethM]

Petrol is not a clear colour, but most also likely absorbed oil from the last mix you had in the can once it got warm and the oils become more fluid.

[AHPP]

Hasn’t had mix in it for ten years. 

[GarethM]

Plus all plastics do age with both UV and petrol as it's a solvent, more noticeable with diesel and even kerosene as that's even more aggressive.

 

I've got yellow drums that are almost brown lugging diesel to small equipment.

[Stere]

The inherent colour of fuel is dependent upon the refining processes used to produce the blendstocks that
go into making a petrol grade. The colour of the blendstocks can vary from Colourless to Yellow depending
upon the refinery, the crude and the processes used to create each petrol blendstock.

[AHPP]

Same pump, same fill, same cans, same historic contents, same everything. Left stored inside, right stored in sunlight. 
 

[AHPP]

Or the butler but I suspect that he is, in this instance, not guilty. 

Edited August 14, 2024 by AHPP

[sime42]

So you've answered your own question then, it must be the sunlight. Either directly or indirectly. Maybe the UV, or increased temperature, or both, cause a reaction between the petrol and plastic to happen at a faster rate than normal. Or something. Too many years since I though about any chemistry.