Applications of P204 D2EHPA Extractant

P204 D2EHPA extractant (Di-2-ethylhexyl phosphoric acid) is a widely used acidic organophosphorus extractant, playing a crucial role in hydrometallurgy, nuclear fuel reprocessing, rare earth element separation, and wastewater treatment.

Its main applications and characteristics are as follows:

1. Metal Extraction in Hydrometallurgy

D2EHPA is a cation exchange extractant that effectively extracts various metal cations, particularly suitable for the extraction and separation of the following metals:

• Rare Earth Elements (REEs):

P204 D2EHPA extractant can selectively extract light rare earth elements (such as La, Ce, Pr, and Nd) from sulfuric acid or chloride systems, often used for the fractional separation of mixed rare earth elements. Selective extraction of different rare earth elements can be achieved by adjusting the pH of the aqueous phase.

• Uranium (U) and Thorium (Th):

In the nuclear industry, D2EHPA can be used to recover uranium and thorium from acidic leaching solutions, especially in phosphate rock or monazite processing.

• Transition metals such as zinc (Zn), cobalt (Co), nickel (Ni), and manganese (Mn):

Widely used in zinc smelters for impurity removal from zinc sulfate solutions (e.g., cadmium and iron removal), and also for cobalt-nickel separation.

2. Nuclear fuel reprocessing: In spent fuel reprocessing processes, D2EHPA can be used to:

• Separate actinides (e.g., Am, Cm) from high-level radioactive waste;

• Improve separation efficiency when used in conjunction with neutral extractants such as TBP (tributyl phosphate).

3. Environmental engineering and wastewater treatment:

• Remove or recover toxic metal ions (e.g., Cd²⁺, Pb²⁺, Cu²⁺) from industrial wastewater containing heavy metals (e.g., electroplating, battery manufacturing wastewater);

• Due to its good selectivity and reversibility, it is suitable for constructing closed-loop recovery systems.

4. Synergistic Effects with Other Extractants
P204 D2EHPA extractant is often used in combination with the following extractants to enhance performance:

• TBP (tributyl phosphate): Inhibits third-phase formation and improves metal loading capacity;

• DY272: Improves selectivity for heavy rare earth elements or cobalt and nickel;

• Kerosene or sulfonated kerosene: Acts as a diluent to adjust viscosity and interfacial tension.

5. Advantages and Disadvantages

Advantages
Disadvantages
High extraction efficiency for multiple metals
Strong acidity, corrosive to equipment
Selectivity can be adjusted by pH
Easily emulsified, requires the addition of phase modifiers
Low cost, industrially mature
Weak extraction ability for heavy rare earths
Can be back-extracted and regenerated, recyclable
Limited stability in strong acids

6. Typical Process Conditions

• Extraction pH: Typically 1.5–4.0 (depending on the metal);

• Diluent: Sulfonated kerosene or n-dodecane;

• O/A ratio: 1:1 to 5:1;

• Back-extraction agent: Commonly 4–6 M HCl or H₂SO₄.

Summary
P204 D2EHPA extractant, due to its high efficiency, economy, and adjustable selectivity, has become one of the most commonly used acidic phosphorus extractants in industrial extraction, especially indispensable in rare earth and non-ferrous metal metallurgy. With the development of green chemistry and resource recycling, its application prospects in high-value metal recovery and environmental protection continue to expand.

Our metal extractants as below, if you need any kind, please ask us:

1. P204 (D2EHPA or HDEHP) This is used for first step to remove impurity for laterite nickel ore.
2. DY319 high efficiency nickel cobalt co-extraction extractant for battery recycle, can take out nickel and cobalt together from Lithium battery electrolyte.
3. DY272 Nickel cobalt separation extractant, it can take cobalt out from nickel cobalt solution, then leave pure nickel.
4. DY988N/DY973N/DY902/DY5640 copper solvent extraction reagent.
5. P507 non-ferrous metal extractant for copper, zinc, cobalt-nickel, cadmium, gold-silver, platinum group metals, rare earths and so on.
6. DY377 efficient nickel and diamond separation extractant.
7. DY366 Scandium extractant.
8. DY316 Lithium extractant.
9. DY-SS-01 extractant for iron, calcium, cadmium and scandium at different pH values.