JPS6237715B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses a petroleum-based hydrocarbon to extract an oil extractant (hereinafter simply referred to as an extractant) consisting of one or more selected from the group consisting of alkyl phosphoric acids, phosphoric esters, oximes, or primary to quaternary amines. Fe ions extracted into diluted organic solvent, Fe
It concerns the stripping of chloride complexes. Conventionally, it is not possible to remove Fe ions extracted into the organic phase and Fe chloride complexes by increasing the concentration of HCl or Fe ions in the stripping solution.
For this reason, Fe in the organic phase could not be economically peeled off. For this reason, no one other than the present inventor has reported that an economic method for extracting and separating Fe from an aqueous solution containing Fe by a solvent extraction method has been made. The inventor has filed a patent application for these methods in 1970-
No. 31550, Patent Application No. 1984-055048, Special Application No. 1973-
No. 089433, Patent Application No. 144861 or Patent Application No. 1973
−118598, but both are 2
By using more than one type of organic solvent and using them in multiple stages, we can take advantage of the characteristics of each.
Although this method discloses a method for economically extracting Fe and recovering acid, it has the disadvantage that the process becomes complicated and the equipment cost increases. As a result of various studies, the present inventor found that Fe in organic solvents
overcame these drawbacks of the conventional method and completed the present invention. That is, the gist of the present invention is that one or more selected from the group consisting of alkyl phosphoric acids, phosphoric esters, oximes, or primary amines to quaternary amines. When stripping Fe ions extracted into an organic solvent obtained by diluting an extractant with a petroleum-based hydrocarbon, the organic solvent phase is brought into contact with a gaseous reducing substance alone or in the presence of a catalyst. The iron ion stripping method is characterized by changing the valence of iron by changing the valence of iron to facilitate stripping, and then stripping the Fe by contacting it with water or an aqueous solution containing a mineral acid or an organic acid. Of course, one or more of alkyl phosphoric acids, phosphoric esters, oximes, and amines can be used as the extractant. The alkyl phosphoric acid used in the present invention is a compound shown below.

【formula】

【formula】

【formula】

[expression] or

[Formula] R represents an alkyl group. (wherein R in the above formula is generally an alkyl group containing 4 to 14 carbon atoms). Further, the phosphoric acid ester is a compound represented by the following formula.

【formula】 【formula】

[Formula] or

[Formula] (wherein R is an alkyl group containing 4 to 14 carbon atoms). Primary amines to quaternary amines are shown below, and one example used in the test is shown, but similar polymeric amines can of course also be used. Primary amine: RN or R ₂ NH ₂ (where R is 4
is an alkyl group containing ~18 carbon atoms), and the following were used for testing: CH ₃ C (CH ₃ ) ₂ CH ₂ C (CH ₃ ) ₂ CH ₂ C
(CH ₃ ) ₂ CH ₂ C (CH ₃ ) ₂ CH ₂ C (CH ₃ ) ₂ NH ₂ Secondary amine: R ₂ N or R ₂ NH (where R is 4
an alkyl group of ~18 carbon atoms), and the following were used for testing: Tertiary amine: R ₃ N or R ₃ NH ₂ (where R is 4
(alkyl group of ~8 carbon atoms), and the following were used for testing: Quaternary amine:

[expression] or

[Formula] (wherein R is an alkyl group having 6 to 18 carbon atoms) An example of an oxime used in the present invention is shown below. Oximes similar to this are used, such as General Mills Chemical's trade names LIX64, LIX65, LIX70, LIX34 or LIX54. The petroleum hydrocarbon diluent used in the present invention may include aromatic hydrocarbons, aliphatic hydrocarbons, and miscellaneous hydrocarbon mixtures such as kerosene. The concentration of the extractant is determined by the properties of the liquid to be treated, the concentration and quality of the substance to be recovered, etc. Generally, the concentration of extractant is between 2% and 95% (by volume). Next, the gaseous reducing substances used in the present invention are H ₂ gas, H ₂ S gas, CO gas, and SO ₂ gas. Catalysts can also be used to promote reduction, but the catalysts used in the present invention include metal nickel called Raney nickel, cobalt,
Includes copper, iron, copper-chromium oxide, nickel oxide, and cobalt oxide. Hereinafter, the present invention will be explained in detail based on the drawings. First, as shown in the flow sheet of Figure 1, Fe ³⁺
The HCl or H ₂ SO ₄ solution (A) is extracted with an organic solvent diluted with a petroleum hydrocarbon diluent as an extractant (extraction step), and the obtained organic solvent phase is sent to the conversion step, where it is After contacting with a gaseous reducing substance (E), e.g. ^hydrogen gas, which is charged at
Fe ²⁺ is stripped by contacting it with the stripping agent (B) charged in the Fe ²⁺ stripping process, i.e., water or an aqueous solution containing mineral acid or organic acid, and the organic solvent is regenerated and reused in the extraction process. Fe ²⁺ in the circulated and recovered aqueous phase is sent to Fe recovery step C. At least a portion of the aqueous phase from which Fe ³⁺ ions and Fe chloride complexes have been extracted in the extraction step is recycled to the iron-containing material treatment step (D) with HCl and H ₂ SO ₄ . Gaseous reducing substances (E)
H ₂ , H ₂ S, SO ₂ , CO, etc. can be used as the catalyst, and a reduction catalyst may be added if necessary. Figure 2 shows the organic solvent solution in which Fe ³⁺ ions and Fe chloride complexes were extracted from Fe ³⁺ -containing HCl or H ₂ SO ₄ solution (A), and the extractant was diluted with petroleum-based hydrocarbons. The Fe ³⁺ ions in the organic solvent are converted into Fe ²⁺ by the generator hydrogen generated at the cathode.
FIG. 7 is a diagram showing a flow sheet of another embodiment in which the valences of ions and complexes are converted and at the same time Fe converted into an aqueous stripping agent solution passing through a cathode chamber is stripped to regenerate an organic solvent. Figure 3 shows the relationship between the extraction rate of Fe ³⁺ ions and Fe ²⁺ ions and pH using alkyl phosphoric acid, and shows that Fe ²⁺ ions can be removed using an aqueous solution with a pH of 3 or less. show. Figure 4 shows Fe ³⁺
HCl to extract ions and Fe ²⁺ ions as a complex
The relationship between concentration and extraction rate shows that extraction occurs when the HCl concentration in the aqueous phase is low, indicating that stripping cannot be performed when the Fe and HCl concentrations in the stripping solution are high. The present invention will be specifically described below with reference to Examples and Comparative Examples. Example 1 As an extractant, an organic solvent prepared by diluting D ₂ EHPA selected from a group of alkyl phosphoric acid varieties with n-paraffin to a concentration of 50% was used in the test. H ₂ SO ₄ 380g/
, Fe ³⁺ 42 g/aqueous solution was brought into contact with the above organic solvent to obtain an organic solvent solution containing Fe ³⁺ ions at a concentration of 18.6 g/a. This was used in the following tests (a) to (d). (b) 100g/100g of this organic solvent solution (organic phase)
H ₂ SO ₄ (aqueous phase) and organic phase/aqueous phase (volume)
(hereinafter abbreviated as O/A) = 1, and after shaking for 10 minutes, the amount of Fe ions transferred to the aqueous phase was 0.01 g/or less (comparative example). (b) Next, we brought it into contact with 150g/HCl at O/A=1, and after shaking for 10 minutes, we measured Fe in the aqueous phase.The Fe ion concentration was 11.2g/1 stage, and it was 60.2
% peeling rate was obtained (comparative example). (c) Then contains Fe ²⁺ 100g/(in the form of FeSO ₄ ), (NH ₄ ) ₂ SO ₄ 40g/, and H ₂ SO ₄ 50
A cathode is inserted into an aqueous solution containing Fe 3+ and a current is passed between it and an anode separated by a diaphragm, and an organic phase containing Fe ³⁺ at a rate of 18.6 g/ is formed into droplets with a diameter of 1.5 to 2 mm. When the organic phase was passed for 5 minutes, Fe ions were found to be 0.1 g/less or less (Example). Example 2 D ₂ EHPA was selected from the alkyl phosphate variety group, and tributyl phosphate (TBP) was selected from the phosphate ester variety group, diluted with isoparaffin, and their concentrations were adjusted to 30% (by volume) and 20% (by volume), respectively. An organic solvent solution (organic phase) diluted to a volume of This organic solvent solution was contacted with an HCl solution containing Fe ³⁺ ions to extract both Fe ³⁺ and Fe chloride complexes into the organic phase, and an organic solvent with an Fe concentration of 21.4 g/L was used for the test. (b) When this organic solvent was brought into contact with water, O/
After shaking for 10 minutes at A=1, it transitioned to an aqueous phase.
When the amount of Fe was measured, it was 6.9 g/(comparative example). (b) When the sample was brought into contact with a 150 g/HCl solution at a ratio of O/A=1, the amount of Fe transferred into the aqueous phase was 8.4 g/(comparative example). (c) In addition, a Raney nickel catalyst with a Ni content of 50% was suspended in the organic phase at a rate of 100 g/ _H2 gas was blown into the organic phase for 10 minutes, and then the organic phase was taken out.
After contacting with an aqueous solution containing g/H ₂ SO ₄ at a ratio of O/A=1 for 10 minutes, the aqueous phase was analyzed and found to have a Fe concentration of 18.9 g/(Example). (E) 125g of FeCl ₂ / in the electrolytic cell (cathode chamber),
Fe in the organic phase after passing an organic solvent with a droplet size of 2 to 3 mm for 5 minutes through an aqueous phase containing 60 g of NH ₄ Cl/
When measured, Fe was 0.42 g/(Example). Example 3 LI×65 was selected from the oxime variety group, D ₂ EHPA was selected from the alkyl phosphate variety group, TBP was selected from the phosphate ester variety group, and TOA was selected from the polymer amine variety group, and each was diluted with an aromatic hydrocarbon. , and the respective concentrations were 5%, 30%, 10%, and 5%. Fe was extracted by contacting with an HCl solution containing Fe ³⁺ ions, and an organic solvent containing Fe at a concentration of 15.4 g/L was used for the test. Blow SO ₂ gas into the phase machine for 5 minutes, then 50
g/Fe of the organic phase after contact with H ₂ SO ₄ solution
When the amount was analyzed, it was 2.1g/. Fe ³⁺ in the aqueous solution underlying these examples
The relationship between the extraction rate of ions and Fe ²⁺ ions and pH is shown in Figure 3. Figure 4 shows Fe ³⁺ ,
The relationship between the extraction rate of Fe ²⁺ chloride complex and HCl concentration is shown. In the figure, the horizontal axis is the HCl concentration (g/
), and the vertical axis shows the extraction rate. Figure 5 shows an equilibrium diagram of the Fe chloride complex. In the figure, curve a is an equilibrium diagram of the Fe chloride complex caused by a reducing solution, and curve b is an equilibrium diagram of the Fe chloride complex caused by water. Figure 6 shows the Fe peeling equilibrium curve,
Curve c represents Fe in the organic phase after contact with a reducing substance.
Equilibrium curve when peeled at 50g/H ₂ SO ₄ , curve d
shows the peel equilibrium curve with 150 g/HCl. Further, when the present invention is implemented, there are the following advantages. (1) In the hydrometallurgical process in the non-ferrous metallurgy industry,
Solvent extraction can be used in the separation process of Fe ions and is also economical, so in addition to removing conventional Fe ions, the loss of coexisting valuable metals is reduced, making it more economical. (2) In addition to valuable metals. Unused resources such as leaching residue, slag, ore, or silicate ore, which contain relatively large amounts of Fe, can be leached out using strong acids. (3) Since waste acids (mineral acids or organic acids) used for surface treatment of metal products and materials can be economically recovered, a closed circuit is formed and pollution is reduced. (4) Waste treatment using the conventional thermal decomposition method
Compared to HCl recovery, it uses less energy and is more economical. In addition, since it operates at room temperature, it is easy to select corrosion-resistant materials, and since it is a simple device, it is possible to manufacture devices with low maintenance costs. Because of this, there is a wide range of factories available. (6) Compared to the neutralization method, there is no sludge generation, so there is no need for disposal costs, and since high-purity electrolytic iron is recovered, sludge treatment does not need to be considered in the location conditions of the equipment. These include things like working on something.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a flow sheet of an embodiment of the method of the present invention, FIG. 2 is a diagram showing a flow sheet of an embodiment of the present invention in which Fe valence conversion and stripping are performed simultaneously in the cathode chamber of an electrolytic cell, Figure 3 shows the
A diagram showing the relationship between Fe ³⁺ ion, Fe ²⁺ ion extraction rate and PH, Figure 4 is a diagram showing the relationship between Fe ³⁺ and Fe ²⁺ chloride complex extraction rate and HCl concentration, Figure 5 6 is a diagram showing a peeling equilibrium curve of Fe chloride complex, and FIG. 6 is a diagram showing a Fe peeling equilibrium curve.

Claims (1)

[Claims] 1 Fe ions and Fe chloride complex extracted in an organic solvent prepared by diluting an extractant selected from the group consisting of alkyl phosphoric acid, phosphoric acid ester, oxime, or primary amine to quaternary amine with petroleum hydrocarbon. For stripping, the valence of Fe is changed by contacting the Fe ³⁺ in the organic solvent phase with a gaseous reducing agent in the presence or absence of a catalyst in the organic phase, and then with water or minerals. A method for removing iron ions, the method comprising removing Fe by contacting with an aqueous solution containing an acid or an organic acid.