Disodium hydrogen phosphate (DSP)
Disodium hydrogen phosphate (Na2HPO4) is a sodium salt of phosphoric acid. It
is a white powder that is highly hygroscopic and water soluble.
Other names:
Disodium hydrogen orthophosphate
Sodium hydrogen phosphate
Sodium phosphate dibasic
di-Sodium Phosphate
Identifiers
Specification: Disodium Phosphate Anhydrous
Items
Spec
Na2HPO4(on dried
material) %
%≥
DSP
DSP·2H2O
DSP·7H2O
DSP·12H2O
98
98
98
98
SKU:D9022
CAS number:
7558-79-4 (anhydrous)
10028-24-7 (dihydrate)
7782-85-6 (heptahydrate)
pH (1% water
8.5-10.0
solution)
8.5-10.0
8.5-10.0
8.5-10.0
10039-32-4 (dodecahydrate)
HS Code(US): 2835220000
Properties
Heavy metals, as Pb
%≤
0.001
0.001
0.001
0.001
Molecular formula: Na2HPO4
Molar Mass:
141.96 g/mol (anhydrous)
Arsenic, as As
%≤
0.0003
0.0003
0.0003
0.0003
177.99g/mol(dihydrate)
268.07 g/mol (heptahydrate)
Fluoride, as F
%≤
0.005
0.005
0.005
0.005
Water insoluble
%≤
0.2
0.2
0.2
0.2
358.14g/mol(dodecahydrate)
Appearance: white crystalline
Density:
1.064 g/cm3(anhydrous)
1.52g/ cm3(dodecahydrate)
Loss on Ignition
%≤
5.0
18.0-22.0
42.0-46.0
61.0
Melting Point: 250°C Decomp.
Solubility in Water:
7.7g/100mL (20 °C)
Protection
Do not ingest. Do not breathe dust. Wear suitable protective clothing. In case of insufficient
ventilation, wear suitable respiratory equipment. If ingested, seek medical advice
immediately and show the container or the label. Keep away from incompatibles such as
acids, alkalis.
Packing and
Storage
Plastic woven bag inner with plastic bag in In 25kg /50 kg/500kg/1000kg net.
It must be prevented from dampness and water. Be sure that it is not necessary to strain to
reach materials, and that shelves are not overloaded. d. Keep container in a cool, wellventilated area.
Applications
 It is used commercially as an anti-caking additive in powdered products. It is also
known as disodium hydrogen orthophosphate, sodium hydrogen phosphate or
sodium phosphate dibasic. It is commercially available in both the hydrated and
anhydrous forms.[pH of disodium hydrogen phosphate water solution is between 8.0
and 11.0, meaning it is basic.
 Disodium phosphate is used in Cream of Wheat to quicken cook time, and Jell-O
Instant Pudding for thickening, as described on the ingredients panel of the product
package.
 Disodium phosphate is used in conjunction with trisodium phosphate in many
steam-boiler applications. It supplies the inventory of free phosphates to retard
calcium scale formation.
 Monobasic and dibasic sodium phosphate is used as a saline laxative to treat
constipation or to clean the bowel before a colonoscopy.
*Data from Wikipedia