Algae air purification

[Leila Choudhry]

Whilst it's likely true that even if all of the trees on land were cut down that oxygen would still be produced from the algae in the seas (although I wouldn't advocate it) can anybody critique this fancy system for use on the smaller scale:

 

https://www.scienceforums.net/forum/61-applied-chemistry/

[swansont]

You’ve linked to the applied chem board here at SFN.

[TheVat]

Phytoplankton in the oceans produces around 50% of our oxygen.  If land sources were eliminated - and such a catastrophe would likely knock out the plankton as well - it would not be hypoxia that killed us.  Atmospheric oxygen would stick around for thousands of years - it's the CO2 buildup (causing hypercapnia, aka CO2 narcosis) that would get us first.  Well actually, starvation and broiling, then hypercapnia to mop up any survivors.  If humans were foolish enough to let all plants die off, I think they would be few and not equal to such tasks as farming big ponds of chlorella or other champion photosynthesizers.

[Leila Choudhry]

2 hours ago, swansont said:

You’ve linked to the applied chem board here at SFN.

I can't believe I did that !

https://www.yankodesign.com/2024/04/05/this-natural-air-purifier-uses-algae-to-remove-harmful-chemicals-from-the-air-we-breathe/?utm_source=rss&utm_medium=rss&utm_campaign=this-natural-air-purifier-uses-algae-to-remove-harmful-chemicals-from-the-air-we-breathe

[exchemist]

8 hours ago, Leila Choudhry said:

I can't believe I did that !

[link deleted]

This looks like a ridiculous gimmick to me, designed to get silly people to waste their money while feeling somehow vaguely "green" as they do so. I'm tempted to suggest the "Y" in the brand name is a misprint. There's just no way having a thing like this bubbling away in a corner is going to give you measurably more oxygen, which in any case you don't need. As for the nebulous claim about capturing "pollutants", what pollutants are they talking about and what evidence is there that these algae will capture them?   

Edited May 1 by exchemist

[Phi for All]

4 hours ago, exchemist said:

As for the nebulous claim about capturing "pollutants", what pollutants are they talking about and what evidence is there that these algae will capture them?   

And even if it did capture some pollutants, they make another claim that you can harvest biomass from this for use as a 3D printing medium. Why are we make everyday items out of polluted materials? If we don't want to breathe them, is touching them on the daily a good idea?

[CharonY]

There are some attempts in that direction, mostly targeted at toxic VOCs. From what I recall, it seems that likely microbes are responsible for oxidizing some of the VOCs and breaking them down . But I don't think that algae were shown to do that. Conversely, I vaguely remember that some algae actually release VOCs (though I cannot recall whether those were in any form harmful). 

The provided link paints a very poor picture of the capabilities of the company, considering they are conflating CO2 capture with capture of harmful substances (via photosynthesis, no less). Failing that much at basic biochemistry does not inspire confidence. The blurb also seem to suggest that this is just an exhibit, likely putting some algae (or even just a green liquid) into a stand. A real bioreactor for cyanobacteria or algae needs quite a bit more to work. And randomly growing cyanobacteria can also produce toxic microcystins. So there is also that.

From what I remember the carbon yield (for fuel or plastic production) was also rather low. I am also skeptical that oxygen production from those volumes would be significant, but I may be wrong.