Help me with some chemistry: Distilling methyl salicylate

Game Talk The Lab
1

I am working on a PR adding wintergreen as a minor food source and as a resource to make some painkillers. Please be aware that I am not good in chemistry at all. I suffered in chemistry class at school.

We already have mugwort and similar oils, I could replace the use_action and recipe with what I want and be happy. But I want more details and realism here.
Wintergreen is a natural source of methyl salicylate, aka aspirin (if I got that right), a good painkiller.
So if you got the essential oil you can add a bunch of oil as a carrier oil, right? Basically to dilute it so you do not overdose.

And if you have the “pure” essential oil, there is some way to distill the methyl salicylate from it, you could use to actually make aspirin tablets, did I get that right? Could someone of you help me in figuring out the ingame crafting steps for this?
I already found these resources (from educational institutions no less, which should be a good and reliable source) which look promising:

Also I do not know how accurate this is but I made it so you can chew wintergreen leaves (according to my research they taste sweet but have a horrible bitter aftertaste, meaning you get a morale penalty) for an unreliable and weak painkiller.

2

I hope you expected a detailed answer :slight_smile:
You need to saponify methyl salicylate and then isolate the pure acid (HCl will do instead of H2SO4) after which if you need acetylsalicylic acid (aspirin) you acetylate salicylic acid with acetic anhydride and sulfuric acid.
Description: 3 ml of methyl salicylate and 12 g of NaOH in 50 ml of H2O are boiled for 30-45 minutes (until the turbidity and smell of oil disappear) then ~ 16 ml of H2SO4 98% or the equivalent of HCl pH is poured in this case, the pH should be 2, then the solution is cooled for ~ 10 minutes and filtered (after recrystallization from hot water, about 1.2 g of salicylic acid is obtained)

3

To obtain methyl salicylate itself, the essential oil is distilled with steam until the turbidity disappears in the distilled water, using a ratio of 9 ml of H2O for every 1 ml of essential oil. The distilled mixture of water and methyl salicylate is extracted twice with dichloromethane in a ratio of 7.5 ml per 1 ml of oil, which is subsequently dried with anhydrous magnesium sulfate, after which dichloromethane is distilled off to obtain pure methyl salicylate as a residue.