2 replies to this topic

[Adem]

Hello all

 

 

Just for curiosity. I have heard that some third world countries refineries use a process of "hiding sulphur content" when refining the crude oil instead of removing it. Is this possible or is just a futility?

 

Thank you

[PingPong]

You probably read something about mercaptan oxidation. This is however only used for light petroleum fractions such as LPG, naphtha, kerosene. It does not remove sulphur so after burning the "hidden" sulphur still produces the same amount of SO₂ (SO₂ emission) as if it were not "hidden". Purpose is only to reduce the smell and the acidity of the petroleum fraction.

 

For example: jet fuel in burnt in international airspace and therefor sulphur spec is very relaxed. To adress the mercaptan problem a refinery can chose to hydrotreat the kerosene, thereby removing the sulphur from the kerosene in the form of H₂S which is subsequently turned into pure sulphur in a Claus unit. Hydrotreating also reduces aromatics content and consequently increases smoke point. If smoke point is considered good enough it is cheaper to simply oxidise the mercaptans and let the sulphur end up in the (international) atmosphere as SO₂ and let it be everybodies problem......

[Adem]

Hello PingPong

 

Thank you for your explanation. I was talking with a friend and he tell me that some refineries in third world countries cheat by "hiding" sulfur content and when the car uses the diesel has engine problems because the amount of sulfur is more or less the same.