DAP Fertilizer 18-46-0 (Diammonium Phosphate)

Gandi Chemical Solutions supplies DAP Fertilizer 18-46-0 (Diammonium Phosphate) (CAS 7783-28-0) to blenders, distributors and commercial growers. Enquiries for DAP Fertilizer 18-46-0 are quoted against this listing. It is supplied as agricultural grade. Packaging: 50kg bags, 1000kg bulk bags, bulk. Priced by quotation, with a current safety data sheet on every consignment.

DAP Fertilizer 18-46-0 is the workhorse phosphate of commercial agriculture: 46% phosphorus as P2O5, most of it water-soluble, plus 18% nitrogen to carry a crop through establishment. CAS 7783-28-0, formula (NH4)2HPO4. It goes in at or before planting, because phosphorus barely moves in soil and has to be placed where roots will reach it. Granules run 2-4 mm with moisture at or below 1.5%. In solution DAP reacts alkaline, which is the practical difference between it and MAP. It suits neutral and acidic soils, and it is banded away from seed rather than placed against it, because free ammonia released as the granule dissolves will damage germinating seed. Supplied in 50 kg bags, one-tonne bulk bags or loose in bulk.

Where dap fertilizer 18-46-0 is used

DAP is the workhorse phosphate: the highest phosphorus analysis available in a widely traded granular product, with a useful nitrogen kicker alongside it. It goes in early, because phosphorus barely moves in soil and has to be where the roots will be.

• Starter phosphate placed at planting on cereals, maize and oilseeds
• Base dressing on soils testing low in available phosphorus
• Blending component in bulk-blended NPK programmes
• Pasture and fodder establishment where root development is the constraint
• Plantation crop establishment before canopy closure

Key features

• Agricultural grade. Free-flowing granules, 2-4 mm.
• CAS 7783-28-0, (NH4)2HPO4.
• Also ordered as Diammonium hydrogen phosphate, Diammonium Phosphate, Ammonium phosphate dibasic.
• Supplied in 50kg bags, 1000kg bulk bags, bulk, with larger units quoted on request.

Specification and grade

Granular diammonium phosphate at 18-46-0, CAS 7783-28-0, formula (NH4)2HPO4, molecular weight 132.06 g/mol. Nitrogen 18% minimum, phosphorus 46% minimum as P2O5, of which the great majority is water-soluble. Granules run 2-4 mm, moisture is at or below 1.5%, and the product is free-flowing. In solution DAP is alkaline, typically pH 7.5 to 8, which is what separates it from MAP in practice.

Handling and storage

Not classified as hazardous. It is hygroscopic and cakes if it takes up moisture, so keep it sealed and dry. Do not store it with urea in the same open heap, because the two react and the mixture goes wet. The alkaline reaction around a dissolving granule releases free ammonia, which is why DAP is kept away from seed at planting rather than banded against it.

Packaging and supply

Packed in 50 kg bags on pallets, one-tonne bulk bags, or loose in bulk. State the crop, the placement method and the soil pH when you enquire. Those three decide whether DAP or MAP is the right recommendation, and the quotation will say which.

References and related supply

• More from this range: Fertilizers
• Related products: NPK Compound Fertilizer, MAP Fertilizer 11-52-0 (Monoammonium Phosphate), Potassium Chloride Fertilizer 60% K2O (MOP / Potash)
• Independent chemical record: PubChem entry for CAS 7783-28-0