Di-ammonium phosphate (DAP)
Alias: di-ammonium phosphate
CAS No. : 7783-28-0
Molecular Formula: (NH4) 2 · HPO4
MW: 132.06
Character: Colorless transparent monoclinic crystal or white powder. The relative density is 1.619. It is soluble in water,but insoluble in alcohol, acetone, ammonia. It will decompose when the temperature was to 155 ℃. If it was exposed in air,it would gradually lose ammonia to be formed of ammonium dihydrogen phosphate. aqueous solution is alkaline. The reacting of DAP with ammonia gave ammonium phosphate.
Uses: Fertilizer-grade is mainly used high concentrations of nitrogen and phosphorus compound fertilizer. Industrial grade was used for impregnation of wood and fabric in order to increase its durability. It can be used for dry powder extinguishing agent.Also used in the printing plate, tube, ceramic, enamel and other manufacturing.Others are wastewater treatment and flame retardants in military.
Quality standard (reference standard)
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specification
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index
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Technical grade
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Food grade
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(NH4)2HPO4 %≥
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98.0
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98.0
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P2O5 %≥
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52.70
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53.00
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N %≥
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21.00
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21.00
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PH
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7.8-8.5
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7.8-8.5
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F %≤
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----
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0.001
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As %≤
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----
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0.0003
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Heavy metal (Pb) %≤
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----
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0.001
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Water insoluble %≤
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0.1
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0.1
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moisture %≤
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0.2
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0.2
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