If you still want iron from your lava in the new version you can do something like this (using whatever sorting system you prefer):
Lava from the magma crucibles gets sent to igneous extruders set to create obsidian (I have four extruders feeding into a hopper that feeds the first macerator in this picture. Edit: which may or may not be displaying correctly? It shows up some of the time for me).
The obsidian gets run through two macerators in a row to create obsidian dust, which is sent to an industrial electrolyzer.
Output from that is split three ways:
Iron and magnesium dusts are sent straight to the output (in this case, the leftmost chest). You could add more processing here if you wanted (for example, running the iron dust through an electric furnace to get ingots).
Compressed air is sent to an autocrafting table to be emptied, and the empty cells are sent back to the electrolyzer. The diamond chest used here for the crafting table's input is massive overkill, there aren't more than a stack of cells in the system at a time, so the chest only needs to hold one stack.
Silicon cells are sent to the industrial blast furnace, which sends the empty cells back to the electrolyzer and the silicon plates to the output. The furnace uses all standard casings with two lava in the center, which provides just enough heat capacity to make silicon plates.
End result: every 8 lava generated creates one magnesium dust, one iron dust, and one silicon plate. Empty cells are conserved, so you can just feed it a stack or so to get it started and let it run without needing to add more. You can easily add this in parallel to a centrifuge setup so the lava is divided between them to get tin, copper, electrum, and tungsten output as well.