Just placing Chemical Combiner causes massive frame rate drop. When i break/dismantle Chemical Combiner frame rate goes back to normal instantly. I don't see any errors or warnings in console.

Minecraft 1.12.2
Forge 14.23.4.2705
alchemistry-0.7.11
alib-1.0.1
Forgelin-1.7.4

This should be fixed now in v0.7.12 which was just approved on curseforge. If you are still having issues then please comment again