(2019 Archived) - Sequel on the Extraction of Venusian Iron, Aluminium and Silicon

Having written this in 2019, and originally published in 2021.. when I was 15 and 17, there would be inaccuracies that I would correct here. Having removed it, I'm publishing  again, for sake of completion so that the efforts wouldn't have gone to vain:

Assume that we have a well developed system of Venusian system of mining already. Now, all we have to do would be to get useful things out of it. Out of them, I would like to talk on Iron, Aluminium and Silicon – as they are the most easily extractable and metals with a wide range of usages. You see, the Basaltic minerals – Pyroxene, Plagioclase and Olivine – have an essence of particularly Haematite, Alumina and Silica; which are in-essence, the ores of Iron , Aluminium and Silicon respectively. 

Their methods of extraction on the cloud-tops wouldn’t be much different from the Earth. Typically, Iron extraction is based on the principle of reducing Haematite, typically with Carbon Monoxide and the assistance of a blast furnace. Still, the Venusians would have an advantage of obtaining Carbon Monoxide – the reducing agent – as it could simply be obtained by the electrolysis of the Carbon Dioxide outside. Its simplified reaction is as follows ^[1]:

Fe₂O₃ + 3CO → 2Fe + 3CO₂                                                     

Haematite + Carbon Monoxide → Iron + Carbon Dioxide

Haematite is typically impure, with Alumina and Silica mixed into it. To address this issue, we add limestone into the blast furnace, which would decompose into Calcium Oxide (CaO) and Carbon Dioxide (CO₂). The Calcium Oxide will react with the impurities to form slag, which are mostly Calcium Aluminates and Calcium Silicates. Slag is less dense than molten iron and floats on it, allowing the slag and pure molten iron to be extracted separately^[1]. Slag doesn’t typically have much value in the process here on Earth. But it could be the only way of obtaining the Calcium Aluminates and Calcium Silicates, which could surely have many applications that the Venusians might find as useful.

Another (optional) approach would be to reduce pure Haematite with Hydrogen, probably with higher temperatures and an Iron-Chrome or Copper Catalyst. The reaction is as follows ^[55]:

Fe₂O₃ + 3H₂ → 2Fe + 3H₂O                       

Haematite + Hydrogen → Iron + Water

Water is produced as a by-product of this reaction, which could be electrolysed to again retrieve Hydrogen, which to our excitement, could be re-used in this reaction to create a perpetual cycle.

You see, the largest hurdle to Venusian self-sufficiency is infrastructure. Without a consistent metal source, the dream of having more infrastructures would be impossible. That is why the Earth would be the ‘metal source’ until then. Iron, rather Iron with impurities, is an ideal metal to base infrastructure on. The day Iron is readily available on Venus for infrastructure, true self-sufficient growth of cloud-civilization would be a fewer steps away. After industrial-boom in Iron production, Iron could turn out to be quite cheaply manufactured. It could be done so cheaply, in-fact that; it could turn out to be worth the expense of a trip to Earth. Venus could even turn out to be a consistent source of Iron to the Earth too! With mass-scaling of the Venusian Iron industry and no worries of polluting the already abysmal Venus below, the amount of Iron extractable is merely only bounded by our imagination. I could say pretty much the same about Aluminium, Silicon and a majority of the other commodities manufacturable on Venus – not just another haven for humanity, but the to-be industrial hub of the solar system too.

Enough about Iron; how does the production of Venusian Aluminium on compare? Before going into how, we must take into our notice, a mineral named Cryolite. Cryolite (Na₃AlF₆), better known as Sodium Hexafluoroaluminate in the scientific world, has this amazing ability to dissolve Alumina, when molten ^[56]. Similar to Haematite, the Basaltic minerals have an essence of Alumina in them too. The Alumina obtained from the Basaltic minerals and dissolved in molten Cryolite to form a solution.

Once this solution is electrolysed, Aluminium will deposit on the negative Graphite anode, and Oxygen will bubble-off from the positive Graphite cathode. Using this method, it would take an estimated power of 20kWe to create a kilogram of Aluminium.This might is quite expensive in the terms of Mars, which also has to deal with the constraints of less solar energy. It shouldn’t be as expensive on Venus, which receives more sunlight, convertible to electricity ^[55], with a 218% increase in efficiency.

The light-weight nature of aluminium might be helpful in maintaining lift of the cloud-cities, rather than other elements. Some still argue that the strong-and-light Carbon Fibre could also be a better candidate, to be used for the purpose ^[55]. But again, Carbon Fibres could be manufactured from the Carbon obtainable from atmospheric Carbon Dioxide, which is quite abundant. Nevertheless, Aluminium could be mass-produced as many other things, very cheaply with a multitude of usages.

By similar means, the Silica essence in the Basaltic minerals could be extracted and processed into Silicon, which also has a wide range of usages, especially as a semiconducting material.

I would elaborate as to how many things could be made from Aluminium and Silicon, in a consequent chapter, as there are simply a lot of them. Nevertheless, I’ll conclude this chapter with the note that the base metals Iron, Aluminium and Silicon could be extracted from the Venusian surface.

Bibliography

Achinthya Nanayakkara (31.03.2025)

Originally written - 2019