# Phosphoric acid: Overview

How one acid becomes most of the world's phosphate fertiliser

Source page: https://www.materialinsights.org/chemicals/phosphoric_acid/overview/

How one acid becomes most of the world's phosphate fertiliser What this tab covers What the chemical is, how big its market is, what it is used for (with shares, volumes, why it wins and what could replace it), and its chain from raw material to end user. Ends with three things to remember.

Phosphoric acid (H3PO4) is made mainly by the wet process: phosphate rock is dissolved in sulphuric acid, gypsum is filtered off and the acid is concentrated to about 52-54% P2O5. About 45 Mt of P2O5 a year passes through it, most of it reacted on site with ammonia into DAP and MAP. Merchant acid is priced quarterly in India, the largest importer, and reached $1,700/t P2O5 in Q3 2026. Each tonne of P2O5 leaves 4.5-5 t of phosphogypsum, the industry's largest waste problem, and purified acid is now a battery material.
 Volume about 45 Mt P2O5 a year (2025, indicative; most of the 47.8 Mt of P2O5 used in fertiliser passes through wet-process acid, except single superphosphate and direct rock use) Market value about $60 billion at Q1 2026 India contract prices (indicative, basis: 45 Mt x $1,290/t P2O5; most acid is consumed captively) Growth world phosphate capacity to rise from 63.7 Mt to 71.7 Mt P2O5 by 2029 (USGS) USGS MCS 2026 (Phosphate Rock); Argus (2026)

#### Key uses

| Use | Share | Annual volume | Why this commodity | Alternatives |
|---|---|---|---|---|
| **DAP and MAP fertilisers** | 62% | about 28 Mt P2O5basis | Reacting acid with ammonia gives a dense, high-analysis granule (18-46-0 or 11-52-0) that is cheap to ship and store. India, Brazil, the US and South Asia apply DAP and MAP as their main phosphate source. Phosphate tile (USGS MCS 2026); share indicative | Single superphosphate (rock plus sulphuric acid, no phosphoric acid) Nitrophosphates |
| **NPK compounds and triple superphosphate** | 18% | about 8.1 Mt P2O5basis | Acid is combined with ammonia, potash and other nutrients into balanced grades. India's NPK complexes and Chinese compound fertiliser makers are large users. Indicative | Bulk blending of DAP, MOP and urea |
| **Purified acid for food, technical phosphates and LFP batteries** | 8% | about 3.6 Mt P2O5basis | Solvent-extracted or thermal acid feeds food phosphates, metal treatment, electronics and iron phosphate for LFP cathodes. LFP output of 3.47 Mt in 2025 made batteries the fastest-growing use. SNE Research via Battery cathode materials tile (LFP 2025); stoichiometry | Thermal acid from yellow phosphorus (China) |
| **Animal feed phosphates (DCP, MDCP)** | 6% | about 2.7 Mt P2O5basis | Defluorinated acid is reacted with lime to make calcium phosphates for poultry and pig feed. Feed grades need low fluorine and heavy metals. Indicative | Bone meal Phytase enzymes that reduce feed phosphate needs |
| **Detergent and industrial phosphates (STPP), water treatment and other** | 6% | about 2.7 Mt P2O5basis | Sodium tripolyphosphate softens water in detergents in Asia and Africa; phosphates also prevent scale and corrosion in water systems. Indicative | Zeolites and citrates in detergents |

 No public world split of phosphoric acid use was found. Shares are indicative; LFP is derived from SNE Research's 3.47 Mt of 2025 LFP output and stoichiometry. Volumes are share x 45 Mt P2O5.

#### From raw material to user

1. **Phosphate rock mining** World marketable rock was about 250 Mt in 2025, led by China (110 Mt) and Morocco (36 Mt) (USGS).
2. **Sulphur burning** About 2.6-2.8 t of sulphuric acid (about 0.9 t sulphur) is needed per t P2O5 (indicative).
3. **Digestion and filtration** Ground rock reacts with acid in a reactor; dihydrate gypsum is filtered off, giving 26-30% P2O5 filter acid (indicative).
4. **Concentration** Vacuum evaporators raise acid to 52-54% P2O5 merchant grade; fluorine is recovered as fluorosilicic acid (US recovered 45 kt FSA in 2025, USGS).
5. **Granulation or sale** Most acid is ammoniated on site into DAP and MAP; merchant acid ships in rubber-lined tankers to India and elsewhere.
6. **Phosphogypsum stacking** About 4.5-5 t of gypsum per t P2O5 is stacked or, at coastal plants, discharged (indicative).

#### Made from (commodity table)
[P Phosphate rock](https://www.materialinsights.org/commodities/phosphate/)[S Sulfur](https://www.materialinsights.org/commodities/sulfur/)

#### Three things to know

- India's merchant acid contract rose from $1,290/t P2O5 in Q1 2026 to $1,700/t in Q3 2026, up 25% in one quarter (Argus; Fertilizer Daily).
- Each tonne of P2O5 needs about 3.3 t of rock and 0.9 t of sulphur, so the 2026 sulphur shock went straight into acid costs (indicative).
- World phosphate capacity is set to grow from 63.7 Mt to 71.7 Mt P2O5 by 2029 (USGS 2026).

#### Read the tabs
[Production route](https://www.materialinsights.org/chemicals/phosphoric_acid/routes/)[Production](https://www.materialinsights.org/chemicals/phosphoric_acid/production/)[Feedstocks](https://www.materialinsights.org/chemicals/phosphoric_acid/feedstocks/)[Cycles](https://www.materialinsights.org/chemicals/phosphoric_acid/cycles/)[Trading](https://www.materialinsights.org/chemicals/phosphoric_acid/trading/)[Movement](https://www.materialinsights.org/chemicals/phosphoric_acid/movement/)[Regulation](https://www.materialinsights.org/chemicals/phosphoric_acid/regulation/)[Characteristics](https://www.materialinsights.org/chemicals/phosphoric_acid/characteristics/)[Emissions](https://www.materialinsights.org/chemicals/phosphoric_acid/emissions/)

## Other sections

- [Summary](https://www.materialinsights.org/chemicals/phosphoric_acid/index.md)
- [Correlation](https://www.materialinsights.org/chemicals/phosphoric_acid/correlation/index.md)
- [Production route](https://www.materialinsights.org/chemicals/phosphoric_acid/routes/index.md)
- [Production](https://www.materialinsights.org/chemicals/phosphoric_acid/production/index.md)
- [Feedstocks](https://www.materialinsights.org/chemicals/phosphoric_acid/feedstocks/index.md)
- [Cycles](https://www.materialinsights.org/chemicals/phosphoric_acid/cycles/index.md)
- [Trading](https://www.materialinsights.org/chemicals/phosphoric_acid/trading/index.md)
- [Movement](https://www.materialinsights.org/chemicals/phosphoric_acid/movement/index.md)
- [Regulation](https://www.materialinsights.org/chemicals/phosphoric_acid/regulation/index.md)
- [Characteristics](https://www.materialinsights.org/chemicals/phosphoric_acid/characteristics/index.md)
- [Emissions](https://www.materialinsights.org/chemicals/phosphoric_acid/emissions/index.md)
- [Relationships](https://www.materialinsights.org/chemicals/phosphoric_acid/links/index.md)