Sorry for the delay, I tried another cyanide build and it stayed exactly the same. So I checked once again on different sites what could be the cause and a compatibility error seemed to come up a lot. I didn't really think about it since the game actually started and I basically just updated a modpack but I had some mods replaced with equivalents and forgot about it.
I made a few tests and it came out that red's better biomes was the one who caused all of this, it kinda makes sense now with the cyanide output and all but back then I didn't even think about it.
Really sorry to have wasted your time like that, should've looked a bit more into it. And for anyone who has the same kinda problem, just take out half your mods and try, if it doesn't crash, grab half of the second half and continue on. Eventually you'll single out some mods that lead to your problem.
Still, thank you for trying to help me out, really appreciated and have a great rest of your day !