3 ms·

I wonder if these could be used for irrigation without having to run water lines. How much does the MOF cost to produce? What is flow rate? How would wide-sc

by cwkoss 9y ago

I wonder if these could be used for irrigation without having to run water lines. How much does the MOF cost to produce? What is flow rate? How would wide-scale use of these in an area effect the regional climate?

portofcall 9y ago
MOF’s are not mass produced, and while a method has been proposed to scale up production, as far as I know it’s never been tested. It’s also a solvent-heavy process, and often uses a lot of benzene. MIT the university is an amazing thing, but MIT the press release machine is pathetic.
- gene-h 9y ago
  MOFs aren't mass produced, but it is possible to produce large quantities of them. BASF has been able to make double-digit tonnage quantities of MOFs per a single production run[0]. It much simpler to make MOFs than other nanomaterials like carbon nanotubes and graphene. The MOF used in the paper is somewhat expensive as it uses zirconium, but it is possible that MOFs based on other metal ions could be used. [0]https://cen.acs.org/articles/91/i51/Materials-Chemistry-Metal-Organic-Frameworks.html https://cen.acs.org/articles/91/i51/Materials-Chemistry-Meta...
  - philipkglass 9y ago
    Zircon (zirconium raw material) isn't very expensive. Removing hafnium from zirconium compounds to reach nuclear-application purity is expensive. Reducing zirconium compounds to metal is expensive. The authors start with zirconyl chloride, which doesn't have either of those expensive requirements. For anyone else wanting to read the full paper, it's open access in Nature Communications: https://www.nature.com/articles/s41467-018-03162-7 https://www.nature.com/articles/s41467-018-03162-7
  - portofcall 9y ago
    It much simpler to make MOFs than other nanomaterials like carbon nanotubes and graphene. Well yes, but nanomaterials are tough to make, and mass produced graphene is a nightmare. None of that changes the energy requirements to make the stuff, or the hazardous byproducts of production. If it’s not energetically and financially efficient, then it doesn’t compete with desalination, and is useless.
Johnny555 9y ago
Given that it's generating "millimeters" of water (I assume they mean milliliters), it seems unlikely that it's going to scale up to where the water can be dumped into the ground for irrigation, or even used for hydroponic growing. Many food crops lose a lot of water through leave, for example, it takes about 15 gallons of water to grow a head of lettuce, while a human can subsist on about a gallon a day. https://www.treehugger.com/green-food/from-lettuce-to-beef-whats-the-water-footprint-of-your-food.html https://www.treehugger.com/green-food/from-lettuce-to-beef-w...
DubiousPusher 9y ago
A pure MOF based irrigation system that produces enough on demand seems a little far fetched but you don't have to go that far to see something like this as potentially powerful. You could run this thing all year and store the water underground and that could have some cool consequences. Imagine an area with good soil that gets enough rain to take plants 60% of the way through their growing season. Something like this might be able to supplement that supply enough to make it practical to grow there. Or, regions that are normally good for growing but have regular droughts could maybe use it to offset the reduced water. Or, if you can store up enough water through winter, maybe you could run a conventional irrigation system purely off the water from the MOFs. Maybe transporting water is already a way better mitigation to the above scenarios. It really depends on how fast and cheap you can deploy something like this.

by cwkoss 9y ago

portofcall 9y ago

MOF’s are not mass produced, and while a method has been proposed to scale up production, as far as I know it’s never been tested. It’s also a solvent-heavy process, and often uses a lot of benzene. MIT the university is an amazing thing, but MIT the press release machine is pathetic.

gene-h 9y ago
MOFs aren't mass produced, but it is possible to produce large quantities of them. BASF has been able to make double-digit tonnage quantities of MOFs per a single production run[0]. It much simpler to make MOFs than other nanomaterials like carbon nanotubes and graphene. The MOF used in the paper is somewhat expensive as it uses zirconium, but it is possible that MOFs based on other metal ions could be used. [0]https://cen.acs.org/articles/91/i51/Materials-Chemistry-Metal-Organic-Frameworks.html https://cen.acs.org/articles/91/i51/Materials-Chemistry-Meta...
- philipkglass 9y ago
  Zircon (zirconium raw material) isn't very expensive. Removing hafnium from zirconium compounds to reach nuclear-application purity is expensive. Reducing zirconium compounds to metal is expensive. The authors start with zirconyl chloride, which doesn't have either of those expensive requirements. For anyone else wanting to read the full paper, it's open access in Nature Communications: https://www.nature.com/articles/s41467-018-03162-7 https://www.nature.com/articles/s41467-018-03162-7
- portofcall 9y ago
  It much simpler to make MOFs than other nanomaterials like carbon nanotubes and graphene. Well yes, but nanomaterials are tough to make, and mass produced graphene is a nightmare. None of that changes the energy requirements to make the stuff, or the hazardous byproducts of production. If it’s not energetically and financially efficient, then it doesn’t compete with desalination, and is useless.

Johnny555 9y ago

Given that it's generating "millimeters" of water (I assume they mean milliliters), it seems unlikely that it's going to scale up to where the water can be dumped into the ground for irrigation, or even used for hydroponic growing. Many food crops lose a lot of water through leave, for example, it takes about 15 gallons of water to grow a head of lettuce, while a human can subsist on about a gallon a day. https://www.treehugger.com/green-food/from-lettuce-to-beef-whats-the-water-footprint-of-your-food.html https://www.treehugger.com/green-food/from-lettuce-to-beef-w...

DubiousPusher 9y ago

A pure MOF based irrigation system that produces enough on demand seems a little far fetched but you don't have to go that far to see something like this as potentially powerful. You could run this thing all year and store the water underground and that could have some cool consequences. Imagine an area with good soil that gets enough rain to take plants 60% of the way through their growing season. Something like this might be able to supplement that supply enough to make it practical to grow there. Or, regions that are normally good for growing but have regular droughts could maybe use it to offset the reduced water. Or, if you can store up enough water through winter, maybe you could run a conventional irrigation system purely off the water from the MOFs. Maybe transporting water is already a way better mitigation to the above scenarios. It really depends on how fast and cheap you can deploy something like this.