2-Ethylhexyl 2-Ethylhexyl Phosphate (P507)

Properties

♦ Physical State

P507 extractant is typically a clear liquid at room temperature. It is often used in its pure form or

dissolved in an organic solvent, such as kerosene or other aliphatic diluents, for extraction purposes.

♦ Solubility

P507 extractant is sparingly soluble in water but highly soluble in most organic solvents. This

property allows it to form a separate organic phase when mixed with aqueous solutions, facilitating the

extraction process.

 

♦ PH Dependence

The efficiency and selectivity of metal extraction using P507 extractant can be influenced by the

pH of the aqueous phase. The optimal pH range for extraction varies depending on the specific metal

ions and the desired separation conditions.

 

♦ Stability

P507 extractant is generally stable under typical operating conditions. It can withstand moderate

variations in temperature and pH without significant decomposition or loss of extraction performance.

However, extreme conditions or prolonged exposure to high temperatures and strong acids or bases

may degrade its effectiveness.

 

♦ Selectivity

P507 extractant exhibits good selectivity for certain metal ions, especially rare earth elements (REEs).

It can preferentially extract specific metal ions from a mixture of different metals, allowing for their

separation and purification.

♦ Regeneration

P507 extractant can be regenerated and reused in extraction processes. This is typically achieved by

stripping the extracted metal ions from the organic phase using an appropriate stripping agent or

adjusting the pH to release the metal complexes. The recovered P507 extractant can then be recycled

for further extraction cycles.

 

Applications

♦ Rare Earth Element (REE) Extraction

P507 is widely used for the extraction and separation of rare earth elements. It offers excellent

selectivity for REEs, enabling their efficient extraction from aqueous solutions containing a mixture

of metals. The extracted REEs can be further processed and purified for various industrial applications.

 

♦ Uranium Extraction

P507 extractant has been employed in the extraction of uranium from ores and solutions. It

demonstrates good affinity for uranium ions, allowing for their selective extraction and separation

from other metalions present in the system. This is particularly relevant in the nuclear fuel cycle

and uranium mining industry.

 

♦ Transition Metal Extraction

P507 extractant can also be used for the extraction of transition metals, such as nickel, cobalt, and

copper, from aqueous solutions. Its selectivity and efficiency in extracting these metals make it

valuable in various extraction and refining processes.

 

♦ Metal Recovery from Industrial Waste Streams

P507 extractant has been employed in the recovery and recycling of metals from industrial waste streams,

such as spent catalysts, electronic waste, and metal plating solutions. It enables the selective extraction

of valuable metals, allowing for their recovery and subsequent reuse.

 

♦ Hydrometallurgical Process Optimization

P507 extractant is often utilized in the optimization and development of hydrometallurgical processes.

Its performance, selectivity, and efficiency are evaluated in laboratory and pilot-scale studies to determine

the optimal conditions for metal extraction and separation.

 

Process

♦ Raw Material Preparation

The raw materials required for the synthesis of P507 extractant include 2,4,4-trimethylpentyl alcohol and

phosphorus trichloride (PCl3). These materials are obtained and prepared according to the required

specifications and purity.

 

♦ Esterification

The synthesis of P507 extractant involves the esterification of 2,4,4-trimethylpentyl alcohol with phosphorus

trichloride. In this step, the two reactants are combined in appropriate stoichiometric ratios and heated

under controlled conditions, typically using a reflux setup. The reaction is carried out in the presence of a

suitable acid acceptor, such as triethylamine or pyridine, to facilitate the formation of the desired ester

product.

 

♦ Acidification

After the esterification reaction is complete, the reaction mixture is carefully acidified to hydrolyze the

ester and convert it into the corresponding phosphinic acid. This step involves the addition of a strong

acid, such as hydrochloric acid or sulfuric acid, to the reaction mixture while maintaining suitable

temperature and stirring conditions.

 

♦ Purification

Once the acidification is complete, the crude P507 extractant is subjected to purification steps to

remove impurities and by-products. Purification methods may include techniques such as solvent

extraction, distillation, recrystallization, or chromatography. These steps help to isolate and obtain

the desired pure P507 extractant.

 

♦ Drying and Packaging

The purified P507 extractant is typically dried to remove any residual moisture. Then, it is

packaged in suitable containers, such as bottles or drums, ensuring proper sealing to maintain its

quality and prevent contamination. The extractant is often stored and transported in a dry and

cool environment to maintain its stability.

 

Inspection

♦ Inspection process

1. Incoming inspection: The main raw materials,are inspected for their content, appearance

and other main properties.

2. Feeding inspection: the principle of raw material feeding is first-in-first-out, and the appearance

of the main raw materials is randomly inspected according to whether there is a big change in the

storage conditions before feeding.

3. Batch sampling in the production process: During the production process, the main indexes of

each batch of products: content and acid value will be examined three times in different time periods.

4. Storage Inspection: Each batch (4tons) is inspected before storage.

5. Outbound inspection: According to the quantity demanded by customers, the products will be

sampled and inspected.

6. Pre-shipment inspection: according to customer’s requirement, third party inspection can be carried

out on the products before shipment.

♦ Inspection Method

Physical Appearance: Visual inspection

Purity Analysis:Gas chromatography (GC)

Acid Value:Potentiometric titration

Water Content:Moisture analyzers

Refractive Index:Refractometer

Density:Density meter

Marking, packaging, shipping and storage

♦ Marking

Each batch of products should be accompanied by a certificate of conformity, including: the name of the

manufacturer, the name of the product, the production batch number, the net weight per barrel, the quality

level and the implementation of the standard number.weight, quality grade and implementation standard

number.

♦ Packing

Packed in clean and dry plastic drums, net weight 200±0.3kg per drum or 1000±0.5kg, compressed and

sealed after each batch.

♦ Transportation

This product is packed in plastic drums, during transportation and loading/unloading, it should be carefully

and gently put down, and prevent from impact.

♦ Storage

The storage place should be cool, dry and ventilated. Do fireproof and rainproof.