Can't reproduce the bug. What other mods do you have? For me it works fine at both the latest 1.0 with RFP 1.3.10 and 1.1 with RFP 1.3.11.
I tried uninstalling all my mods, even so far as to remove RFP, rebooted, then reenabled only RFP and the weapons addon for RFP and still getting the bug on a new game. If I copy over my existing game file, I can spawn the electrolyzer, but it doesn't show up in the research tree in the original save, a copy, or a new game.