IUPAC-NIST Solubility Database
NIST Standard Reference Database 106

---

 Solubility System: Ammonia with Phosphoric acid, Sulfuric acid, Potassium oxide and Water

---

Components:
   (1) Ammonia; NH3; [7664-41-7]  NIST Chemistry WebBook for detail
   (2) Phosphoric acid; H3PO4; [7664-38-2]  NIST Chemistry WebBook for detail
   (3) Potassium oxide; K2O; [12136-45-7]  NIST Chemistry WebBook for detail
   (4) Sulfuric acid; H2SO4; [7664-93-9]  NIST Chemistry WebBook for detail
   (5) Water; H2O; [7732-18-5]  NIST Chemistry WebBook for detail

Original Measurements:
   Fokina, Z.N.; Kornishina, E.N.; Kim, P.P., Tekhnologiya Mineral'nykh Udobreniy (Leningrad) 63 (1977).

Variables:

   Concentration = Composition at 80 ºC

Prepared By:
   L.V. Chernykh and J. Eysseltová

Experimental Data:   (Notes on the Nomenclature)
  

Solubility isotherms in the NH₄H₂PO₄-H₃PO₄-K₂SO₄-H₂O system at 80 °C.

Solution number	Chemical1	102 * Mass Fraction w1	Chemical2	102 * Mass Fraction w2	Chemical3	102 * Mass Fraction w3	Solid Phase(s)
1	K2O	12.54	NH3	1.41	P2O5	30.36	KHSO4KKH2PO4
2	K2O	11.02	NH3	2.63	P2O5	32.38	"
3	K2O	10.60	NH3	3.55	P2O5	29.40	"
4	K2O	10.20	NH3	5.20	P2O5	28.60	"
5	K2O	6.30	NH3	6.00	P2O5	28.15	(K,NH4)H2PO4
6	K2O	7.29	NH3	5.70	P2O5	29.80	"
7	K2O	5.14	NH3	6.41	P2O5	32.17	"
8	K2O	2.32	NH3	6.61	P2O5	30.76	"
9	K2O	9.03	NH3	0.30	P2O5	40.00	KHSO4KKH2PO4
10	K2O	8.63	NH3	0.65	P2O5	38.90	"
11	K2O	7.36	NH3	2.49	P2O5	39.00	"
12	K2O	6.51	NH3	4.33	P2O5	40.61	"
13	K2O	5.28	NH3	4.82	P2O5	40.40	(K,NH4)H2PO4
14	K2O	3.53	NH3	5.70	P2O5	39.56	NH4H2PO4
15	K2O	0.47	NH3	7.86	P2O5	40.80	"

Part 2. The compilers have used the data in Part 1 to calculate the following values.

Solution number	Chemical1	m1 [mol/kg]	Chemical2	102 * Mass Fraction w2	m2 [mol/kg]	Chemical3	102 * Mass Fraction w3	m3 [mol/kg]	Chemical4	m4 [mol/kg]	Chemical5	102 * Mass Fraction w5
1	NH3	2.66	H3PO4	41.92	13.77	H2SO4	13.06	4.284	K2O	4.284	H2O	31.07
2	NH3	5.12	H3PO4	44.71	15.12	H2SO4	11.47	3.878	K2O	3.878	H2O	30.17
3	NH3	6.09	H3PO4	40.59	12.11	H2SO4	11.04	3.288	K2O	3.288	H2O	34.22
4	NH3	8.85	H3PO4	39.49	11.68	H2SO4	10.62	3.140	K2O	3.140	H2O	34.49
5	NH3	8.33	H3PO4	38.87	9.383	H2SO4	6.56	1.58	K2O	1.58	H2O	42.27
6	NH3	8.75	H3PO4	41.15	10.97	H2SO4	7.59	2.02	K2O	2.02	H2O	38.27
7	NH3	9.73	H3PO4	44.42	11.72	H2SO4	5.35	1.41	K2O	1.41	H2O	38.68
8	NH3	8.40	H3PO4	42.47	9.384	H2SO4	2.42	0.533	K2O	0.533	H2O	46.18
9	NH3	0.68	H3PO4	55.23	21.65	H2SO4	9.40	3.68	K2O	3.68	H2O	26.04
10	NH3	1.36	H3PO4	53.71	19.56	H2SO4	8.99	3.27	K2O	3.27	H2O	28.02
11	NH3	5.11	H3PO4	53.85	19.19	H2SO4	7.66	2.73	K2O	2.73	H2O	28.64
12	NH3	9.66	H3PO4	56.07	21.75	H2SO4	6.78	2.63	K2O	2.63	H2O	26.31
13	NH3	9.89	H3PO4	55.78	19.89	H2SO4	5.50	1.96	K2O	1.96	H2O	28.62
14	NH3	10.3	H3PO4	54.62	17.17	H2SO4	3.68	1.15	K2O	1.15	H2O	32.47
15	NH3	13.2	H3PO4	56.34	16.50	H2SO4	0.49	0.14	K2O	0.14	H2O	34.85

Method/Apparatus/Procedure:
   No information is given. The compilers assume that the methods were the same as those given earlier.¹

Source and Purity of Materials:
   No information is given.

Estimated Errors:
   Solubility: No information is given.
   Temperature: No information is given.

References:
   ¹Baranova, T.N.; Semkin, N.T.; Kim, P.P.; Kornishina, E.N.; Nikandrov, I.S. Tekhnologiya Mineral'nykh Udobreniy (Leningrad) 1977, 55.

---

Distributed by the Office of Data and Informatics of the National Institute of Standards and Technology (NIST) Material Measurement Laboratory (MML).
Website is owned by NIST (an agency of the U.S. Department of Commerce)

---

Last updated: February 18, 2015 (Created: August 17, 2007)