Ion exchange resins can be used for such an application, but this depends of what kind of water do you want to obtain after removal of the ions. For example, to remove just nitrate and some sulfate ions in potable water, it can use Purolite A520E, but this is limited to pH 4.5-8.5 (see technical data attached).

Dear Amirsalar,

please have a look to the paper attached and try to find similar ones. I am currently working on autotrophic denitrification whilst not with granular iron as electron donor at the moment. There are numerous study concerning this topic, at different pH, and some of them reported the possibility to obtain hydrogen from ferrous iron corrosion that contribute to denitrification.

When you deal with iron and your pH is neutral/alkaline, please keep in mind that iron can precipitate and be removed from solution before your desired application effectively starts. Maybe it is not the case of granular zero-valent iron. Please keep trying :)

You can see if this process can be performed for phosphate removal as well. I have no experience about that. Of course phosphate precipitate with ferric iron. So if you manage to produce Fe(III) from zero-valent iron, you might achieve also this goal.

Best,

Stefano

This is the paper...sorry

Dear Cristinel

Thank you for your response. Your right, Ion exchange resins are sufficient and effective in removing different range of ions including nitrate, phosphate, and sulfate; but they need to be regenerated after awhile, and maybe this feature is their disadvantage in compassion to catalyzes which only need to be added to a solution.

In fact I'm looking for something to add to the water (which already has nitrate, phosphate, and sulfate) and reduce the concentration of those ions.

Dear Stefano

Thank you for your answer, explanation, and reference. Based on my literature survey, zero-valent iron nanoparticles (ZVIN) can reduce nitrate concentration even up to 70% which is impressive, but the pH of the solution which these ZVIN should be added to must be so low (pH around 3). In my research, I'm trying to do the same thing but in high pH ( around 11), and because of this pH issue I cant use ZVIN. So I need to find a way to make the ZVIN effective even in high pH, or look for some other materials except ZVIN. If you have any suggestion, or idea, I appreciate it if you share with me.

Regards

Salar

Dear Dr. Pizarro

Thanks for your response. Could you please mention what other noble metal catalysts I can use at higher pH?

And could you tell me what are those processes that can be used to remove/reduce phosphate, and sulfate?

The goal of my research is to remove/reduce the concentration of nitrate, phosphate, and sulfate (specifically nitrate and phosphate), not to precipitate them).

Best Regards

Salar