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We are committed to providing customers with advanced precious metal extraction solutions. Extracting precious metal platinum from the extraction tank generally covers core steps such as pretreatment, dissolution, solvent extraction, stripping and reduction. The specific process is as follows:
Pretreatment: First, crush the platinum-containing waste (such as industrial catalysts, electronic components, jewelry, etc.) into fine particles to increase the reaction surface area; then use strong acids such as concentrated nitric acid to dissolve the base metals (such as copper, iron, magnesium, etc.) in the waste under heating conditions to separate platinum from them; then filter to remove insoluble impurities, and wash the filter residue with clean water to remove residual acid.
Dissolution: Add the pretreated platinum residue to excess aqua regia (a mixture of concentrated nitric acid and concentrated hydrochloric acid) and heat to dissolve. After removing the concentrated nitric acid, a platinum concentrate is obtained. This process requires strict control of temperature and time to prevent platinum loss.
Solvent extraction: Select extractants such as N-2-chlorophenyl-N'-benzoylthiourea and tributyl phosphate, which have good selectivity and extraction ability. The organic phase usually consists of an extractant and a diluent such as toluene, n-octane, isoamyl alcohol or n-dodecane. The organic phase is fully mixed with the platinum concentrate, and the platinum is selectively transferred into the organic phase by adjusting the pH value (4 - 5) and temperature (80 - 85°C). The extraction process is usually carried out in a multi-stage series device to improve efficiency, and the temperature needs to be strictly controlled. After the extraction is completed, the layers are allowed to stand and the organic phase (loaded organic phase) and the aqueous phase (raffinate) are collected separately.
Stripping and reduction: The acidity of the loaded organic phase is adjusted to 0.8 - 1.2 mol/L with hydrochloric acid, and then it is fully mixed with a stripping agent such as thiourea with a concentration of 0.5 - 0.8wt%, and the stripping solution is collected after standing and phase separation. Add a reducing agent such as hydrazine hydrochloride, hydrazine hydrate or formaldehyde to the stripping solution, heat and boil it, so that the platinum is reduced and precipitated to form black sponge platinum, and high-purity platinum powder is obtained after filtration, washing, calcination and cooling.
Equipment and reagents: The extraction equipment includes an extraction tank and a centrifugal extractor. The extraction tank is equipped with an intelligent control system, and the centrifugal extractor has a large processing capacity and low cost. Common reagents include extractants (such as TBP, N235), diluents (such as toluene, n-octane), stripping agents (such as thiourea) and reducing agents (such as hydrazine hydrochloride, hydrazine hydrate or formaldehyde).
With professional extraction tank technology and rich experience, the above process can efficiently extract precious metal platinum and obtain high-purity platinum powder, helping customers achieve excellent results in the field of precious metal recovery.