Sciencemadness Discussion Board

Analysis of Amonium Phosphate

servo - 4-11-2022 at 01:24

Hey everyone,

So I have found a very cheap source of Monoamonium Phosphate MAP and since it's almost 75% price of market I'm skeptical of it's purity

What is the the method for determination of percentage purity of Amonium Phosphate?

Preferably if there is a titration method..
Cheers

B(a)P - 4-11-2022 at 01:49

It would be somewhat crude, but you could add a molar equivalent of a salt such as calcium chloride that will yield a solid, then weigh the dried product.
So you could have 0.1 moles of your MAP and 0.05 moles of calcium chloride each dissolved in appropriate volumes of dH2O. Add the two solutions then filter off the solid, dry and weigh. You can then work out the percentage of the expected yield to determine purity. I have no idea what your potential impurities might be, it might be worth identifying them first. If sulfate is a potential impurity then calcium chloride will obviously not be a good candidate for this test.

Fulmen - 4-11-2022 at 05:04

Ammonia in fertilizers is traditionally determined by adding strong sodium hydroxide and distilling it into acid.

[Edited on 4-11-22 by Fulmen]

Bedlasky - 2-2-2023 at 00:34

Phosphate can be precipitated by magnesium salt in ammoniacal solution as NH4MgPO4.6H2O - this can be then heated to form Mg2P2O7. Magnesium is usually precipitated by solution containing 12 g MgCl, 16 g NH4Cl and 26 ml of 26% NH3 in total volume of 100 ml.