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Comment by CapitalistCartr | Hacker News Reader

I wonder if we could use that as a building material.

Anything that is water soluble is going to be a pretty poor building material, unfortunately. The organics floating about (protozoa, algae, fish) also generally decompose, another undesirable property. The remainder- very very fine silt and microplastics- might be useful.

With all the chemical processing that would be needed to stabilize the salts, mechanical filtering and such, I think we're better off continuing to use bricks and ground sourced gravel and cement. At least the holes we dig can be repurposed into sanitary landfills.

Corals manage it quite effectively

But not efficiently. Scientists think the polyps absorb bicarbonate and calcium ions and deposit calcium carbonate, but they're not really sure of the bio/chemical process involved.

Regardless, a polyp adds about 1mm to 1cm to the reef a year. You can get that right now just by throwing a shovel at the ground where I live.

Even if we split NaCl into its constituent parts -- sodium metal and chlorine gas -- there's not a whole lot that can be done with them.

Sodium is potentially useful towards two applications, off the top of my head. (1) Na2O is used in glassmaking, and it's possible that there are -- or that there can be discovered -- Na2O-enriched glasses that can be used in construction and as a filler substance, i.e. reduced to powder and added to cement. (2) Sodium-based zeolites can potentially be useful for carbon capture. Production of zeolites, however, also requires lots of alumina and silica.

I struggle to think of any large-scale application for all of that chlorine, though. Maybe vinyl chloride production? But the world doesn't need that much PVC...

Also in the production of Sodium batteries, which while significantly lower in energy density compared to Lithium, they have bigger cycle counts (and as such are/can be used to buffer grid based wind/solar generation)

I'm a proponent of just stockpiling it, spray it onto a large basin and form a salt lake, let it evaporate to a solid as deep or as high up as it needs to be. That's a stockpile that can eventually find a use. Or not, in which case it's harmless, assuming the salt doesn't go into the ground. Or does, if it's a desert or otherwise 'dead'.

Those leftovers are water soluble, so either you perform some interesting chemistry to convert them into something more durable or your buildings have to be in arid places (condominium in an old salt mine?)

Probably more practical to use more chemistry and find good uses for sodium and chlorine individually.

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