chemical possibility in oil - 8th graders have questions for a project
A chemical that can be added to crude oil so that the oil solidifies upon contact with water to either seal leaks or to make the oil recoverable sounds like a very good idea. Unfortunately, such a chemical is exceedingly unlikely to exist.

When processing crude oil, you typically want the oil itself and not any additives. That means, the chemical in question would have to be added in concentrations as low as possible. Therefore, it’s reaction with water must be very strong. But this in turn means that the traces of water present everywhere (yes, even inside your sample of crude oil) would almost be enough to cause the reaction. Therefore, outside of water-free atmospheres (used in laboratories under inert gas to perform water and air-sensitive reactions) this chemical would hardly be usable.

A second problem is getting the chemical reasonably dissolved. Crude oil is a very viscous mixture unless heated. To use the chemical effectively, it would need to be added almost immediately and distributed well in the sample of crude oil — which would mean immediately heating the crude oil to such temperatures that efficient mixing is possible (likely under pressure to not lose the more valuable but also more volatile petrol components) right after getting it out of the ground. Especially on oil rigs, I see major difficulties with this process; and it is basically on oil rigs that you would want this chemical the most.

Finally, there is the ‘how would it work’ problem. I have extreme difficulty imagining a reaction with water that would lead to solidification. The only idea I can come up with is a compound that would be liquid at standard conditions but adds water to become a solid which crystallises out of the crude oil phase. However, this solid would likely not do you the favour of crystallising where you need it and you would need so much of it that my first argument becomes invalidated. Therefore, I conclude that such a compound cannot exist.

If such a compound exists, I’m sure we would have heard of it or it would be in use (or have been in use if there are significant and severe environmental issues with it that are worse than the issues with crude oil itself.