Attempting to create desh ingot from chemical plant with mercury light oil and desh blend only works for the first time, then you've to destroy the chemical plant and start again, doing this in loop for each desh ingot you've to produce.

Apparently the chemical plant works well until you place a chest in front of the output face of the plant.
AND apparently this bug happens with every chemical plant that outputs items.

The bug seems to be in TileEntityMachineChemplat.update() at line "if(hasSpaceForItems(itemOutputs) && hasSpaceForFluids(fluidOutputs))", apparently after placing the output chest this start to spam false even if broken.
The failing condition is the "hasSpaceForItems(itemOutputs)"

In the method hasSpaceForItems the issue is in the condition Library.areItemStacksCompatible(stacks[i].copy(), inventory.getStackInSlot(5+i).copy(), false), that starts to spam false, causing the method to return false

Already fixed in dev