KR100843953B1 - Separation, recovery high purity V2O5 and MoO3 from waste catalyst of petrochemisty with vanadium and molybdenum - Google Patents

Abstract

In the present invention, V ₂ O ₅ and MoO ₃ are precipitated by extracting and concentrating only vanadium and molybdenum components in a solution obtained by roasting petrochemical waste catalysts such as desulfurization catalyst, nimo catalyst, and como catalyst at high temperature soda. The present invention relates to a method for separating and recovering a furnace. The characteristics of the present invention are not only able to continuously separate and recover the vanadium and molybdenum components through solvent extraction, but also reduce the generated ammonium wastewater by 10 to 75% compared to the conventional simple soda roasting process, and V ₂ O ₅ And 99% or more of MoO ₃ purity, and 99% or more of water-leached vanadium and molybdenum components.

[Index]

Vanadium, molybdenum, high purity V ₂ O ₅ , high purity MoO ₃ , petrochemical waste catalyst, solvent extraction, ammonium wastewater, recovery rate

Description

Separation, recovery high purity V2O5 and MoO3 from waste catalyst of petrochemisty with vanadium and molybdenum}

1 is a process flow chart of the present invention

The present invention effectively extracts, concentrates and precipitates only vanadium and molybdenum components through solvent extraction in a solution obtained by roasting vanadium and molybdenum components in valuable metals contained in a petrochemical waste catalyst at high temperature soda roasting, and then precipitates them with high purity of V ₂ O ₅ and The present invention relates to a method for producing MoO ₃ , and relates to an industrially useful recovery method that can be used as a raw material for producing ferovanadium and feromolybdenum in terms of resource recycling.

In general, vanadium and molybdenum components of valuable metals contained in spent catalysts are recovered by V ₂ O ₅ form after high temperature soda roasting, followed by water leaching, selective precipitation and calcination, and molybdenum is converted into MoO ₃ , CaMoO ₃ or It is recovered in the form of MoS ₃ , and since the residue is mostly alumina, it is used as a raw material in ceramics or as a heat source when manufacturing cement.

In the above method, V ₂ O ₅ having a recovery rate of about 95% and a purity of about 98% can be produced in terms of purity and recovery rate of the target component, but in the case of molybdenum, a recovery rate of 60 to 80% and a purity of 85 to 95% are achieved. Lower MoO ₃ can be synthesized. In addition, the temperature of the solution should be raised to a maximum of 90 ℃ to increase the recovery rate in the synthesis of MoO ₃ . This is because of low purity and low economic feasibility, domestic production of high-purity MoO ₃ is not produced.

As described above, only molybdenum and vanadium can be selectively extracted and concentrated under normal temperature and atmospheric pressure, deviating from the manufacturing method of low purity low recovery MoO ₃ and intermediate V ₂ O ₅ synthesized by the conventional high temperature soda roasting method. The purpose of the present invention is to provide a method for recovering 99% or more of high purity V ₂ O ₅ and MoO ₃ with relatively low energy cost by introducing a solvent extraction method. In order to achieve the above object, in the present invention, vanadium and molybdenum are extracted as a solvent in an anionic compound state of VO ₃ ^- and MoO ₄ ^2- in a water-leached solution after high temperature soda roasting, and only molybdenum and vanadium, which are target components, are removed from the solvent. The present invention provides a method for producing high purity V ₂ O ₅ and MoO ₃ by re-extracting and concentration of an aqueous alkali solution into an anionic compound, followed by extracting and concentrating only molybdenum again. In particular, the present invention provides a method for obtaining a secondary effect of reducing the high concentration of hardly degradable ammonium wastewater generated by the synthesis of V ₂ O ₅ and MoO ₃ depending on the concentration ratio during solvent extraction ₁₀ to 75%.

The present invention will be described in more detail with reference to the accompanying drawings.

In the present invention, in order to make the water-soluble NaVO ₃ and Na ₂ MoO ₄ , the waste catalyst was added to a 2-fold molar ratio of Na ₂ CO _3, and then mixed with the rotary kiln at 950 ° C. for 4 hours, and then the waste catalyst volume When water was added at a volume ratio of 3 to 5 times and leached at 85 ° C. for 30 minutes, the solids NaVO ₃ (S) and Na ₂ MoO ₄ (S) formed during high temperature roasting were dissolved in water-soluble NaVO ₃ ( ℓ ) and Na ₂ MoO ₄ ( ℓ ) Leached in form. In addition, Al ₂ O ₃ , Fe ₂ O ₃ , SiO ₂ , NiO and the like were leached in a small amount of 0.1% or less in the aqueous solution in which the spent catalyst was leached, and Na ₂ O was leached from 1 to 5%. This may lower the purity in the synthesis of molybdenum and vanadium. In particular, the sodium of Na ₂ O is almost removed in the case of vanadium, but more than 50% of the molybdenum was not removed. Therefore, in order to remove impurities including sodium at room temperature and make high purity V ₂ O ₅ and MoO ₃ , in the 'solvent extraction / concentration I' process of the accompanying drawings, VO _{3 in an} aqueous solution as shown in equations (1) and (2) ^- and extracting MoO ₄ ^2- to extract the R ₃ NHVO ₃ and R ₃ NH ₂ MoO ₄ as the solvent and sodium conditions and residual impurities by the interruption of the extract solution was discharged into the normal waste water.

NaVO ₃ + HCl + R ₃ N ↔ R ₃ NHVO ₃ + NaCl... (One)

Na ₂ MoO ₄ + 2HCl + R ₃ N ↔ R ₃ NH ₂ MoO ₄ + 2NaCl. (2)

Extraction of vanadium and molybdenum of the formulas (1) and (2) under normal temperature and atmospheric pressure is best extracted with the solvent TIOA (tri-isooctylamine), that is, R ₃ N in soda-treated leachate. At this time, R ₃ N is a solvent having a carbon group of 8 and iso structure, and the viscosity is high when the stock solution is used, so the extraction time is long, so dilute to kerosene by volume ratio. The dilution ratio of TIOA / kerosene is most preferably 20-30% / 70-80% in terms of extraction time and efficiency. When extracting, the mixture should be mixed well to increase the efficiency.In the laboratory, the separatory funnel is attached to the shaker and mixed at 400rpm or more.In the case of medium and large pilots or above, even at 400rpm or more from the mixer of M / S (mixer & settler) motor. Mix When mixing, the volume ratio of the solvent to the leachate, that is, the O / A (Organic / Aqueous) ratio, is set to 1, which has the greatest number of collisions, so that the extraction efficiency is the best. If the mixing time is long, the M / S increases, which may cause a lot of equipment investment. Therefore, the mixing time should be adjusted to 2 minutes or less. Therefore, after adjusting the solvent TIOA as described above and administering the acid by the molar ratio of vanadium and molybdenum in the leachate, the mixing time is maintained at 2 minutes or less at O / A = 1 and mixing at 400 rpm or more. Can be adjusted to When the mixture is stabilized for 10 to 30 minutes after mixing, the solvent from which vanadium and molybdenum are extracted due to a specific gravity difference becomes a supernatant, and the remaining aqueous solution becomes a supernatant and is separated. In this case, the supernatant is called extract (extract) by extracting vanadium and molybdenum in a compound state and is lipophilic, and the lower layer is hydrophilic and is called remaining layer (raffinate) after the solute is removed. In an example, 36 ml of 35% hydrochloric acid was administered to 1 L of soda-baked leachate having 1% concentration of vanadium and molybdenum, and O / A = 1, mixing time 2 minutes, and layer separation time 30, respectively. In minutes, the separation funnel was set to a shaker at atmospheric pressure at room temperature, and extracted at 400 rpm. For reference, sulfuric acid may be used instead of hydrochloric acid in the above formulas (1) and (2).

Subsequently, the extract was subjected to back extraction with an alkaline aqueous solution. The reaction scheme is as shown in equations (3) and (4), the solvent is regenerated with R ₃ N and the vanadium and molybdenum compounds are in the form of NH ₄ VO ₃ (NaVO ₃ ) and (NH ₄ ) ₂ MoO ₄ (Na ₂ MoO ₄ ), respectively. Extracted with aqueous solution.

R ₃ NHVO ₃ + NH ₄ OH (NaOH) ↔ R ₃ N + NH ₄ VO ₃ (NaVO ₃ ) + H ₂ O. (3)

R ₃ NH ₂ MoO ₄ + 2NH ₄ OH (2NaOH) ↔ R ₃ N + (NH ₄ ) ₂ MoO ₄ (Na ₂ MoO ₄ ) + 2H ₂ O. (4)

The extracts R ₃ NHVO ₃ and R ₃ NH ₂ MoO ₄ in the formulas (3) and (4) are back extracted under normal pressure with an aqueous alkali solution, that is, a caustic soda and ammonia solution. At this time, the higher the concentration of vanadium and molybdenum in the reverse extraction solution compared to the leachate solution, the greater the reaction efficiency and recovery. Therefore, the volume of alkaline aqueous solution is reduced by 2 ~ 4 times than the soda-baked leachate solution, namely O / A = 2 ~ 4, 2 stages of back extraction stage, mixing time 2 minutes or less, mixing 400rpm or more, bed separation time 10 ~ 30 minutes. By reverse extraction, the concentration of vanadium and molybdenum is automatically concentrated 2 to 4 times compared to the leachate, and the ammonium wastewater generated after the recovery of vanadium and molybdenum from the reverse extraction solution is also reduced by the concentration ratio. For example, 1 L of an extract of 1 L of soda-baked leachate with 1% concentration of vanadium and molybdenum, respectively, was mixed with O / A = 2, that is, 0.5 L caustic 5% solution for 2 minutes, and layer separation. When the separation funnel was set to a shaker at atmospheric pressure at room temperature for 30 minutes and back extracted at 400 rpm, the concentration of vanadium and molybdenum was reversely extracted at 1.8% in the first stage and 0.2% at the second stage, respectively. It can be seen that the concentration is 1.8% or 1.8 times in the first stage. In the waste water, the first stage and the second stage are 0.5 L, respectively, but in countercurrent multi-stage extraction, 0.5 L of the second stage is introduced into the first stage, and eventually the back extraction aqueous solution having a concentration of 2% and a volume of 0.5 L is discharged. As a result, it can be seen that the reverse extraction aqueous solution of twice the concentration compared to the leachate solution can be obtained, and the ammonium wastewater generated after the recovery of vanadium and molybdenum can also be reduced by 50%.

Here, the solvent was recycled back to the extraction process, and the concentrate was adjusted to pH 8.0 of the aqueous solution with ammonium sulfate, hydrochloric acid or sulfuric acid in the vanadium precipitation step of the accompanying drawings to precipitate as shown in Equations (5) and (6). The precipitated NH ₄ VO ₃ (S) was calcined as a hydrated sludge to obtain V ₂ O ₅ (S) as an orange powder.

NH ₄ VO ₃ ( l ) ← pH adjustment [HCl (H ₂ SO ₄ )] → NH ₄ VO ₃ (S) + β. (5)

2 NaVO ₃ ( L ) + (NH ₄ ) ₂ SO ₄ ← pH adjustment [HCl (H ₂ SO ₄ )] → 2NH ₄ VO ₃ (S) + Na ₂ SO ₄ + β. (6)

Where β is salt and water.

In the above formulas (3) and (4), caustic soda and ammonia aqueous solution may be selectively used, but NH ₄ VO ₃ may be precipitated due to supersaturation of vanadium concentration from 0.5% in the neutral region in water solubility. there was. Since this hinders the smooth liquid flow in the solvent extraction process, in consideration of the vanadium concentration during back extraction, only ammonia aqueous solution was used at a concentration of about 0.5% or less, and caustic soda and ammonia aqueous solution were used at 0.5% or more. (A) and (B) flows in the accompanying drawings indicate that the filtered solution was extracted by back-extraction with aqueous ammonia solution from the concentrated solution before the vanadium precipitation process. B) Molybdenum precipitation was carried out by passing through the flow. In the above-mentioned 'solvent extraction I' process, vanadium and molybdenum are selectively extracted in a solvent under normal temperature and atmospheric pressure, so that Al ₂ O ₃ , Fe ₂ O ₃ , SiO ₂ , Na ₂ O, NiO, etc. remain in the lower liquid raffinate, and vanadium precipitation The process naturally removed impurities. In addition, the sodium adsorbed on NH ₄ VO ₃ (S) in the formula (6) was able to lower the NH ₄ VO ₃ (S) to 200ppm or less by washing twice in the filtration and washing process. And in (5) and (6), the reaction efficiency was higher and the reaction time was shorter than the water leachate at room temperature and normal pressure. The washed NH ₄ VO ₃ (S) was put in a drying furnace and calcined at 500 ° C. for 2 hours to obtain high purity V ₂ O ₅ .

In the 'solvent extraction / concentration II' process of the accompanying drawings in the present invention, solvent extraction was performed using (b) flow as a raw material. The conditions were carried out similarly to the 'solvent extraction / concentration I' process described above. In this process formula VO ₃ in a small amount of unreacted MoO ₄ ^2- and the previous process in an aqueous solution, such as ⁽⁷⁾ was extracted in a solvent with R ₃ NH ₂ MoO _4, and R _{3 3} NHVO state, ammonium chloride, sodium chloride Ammonium wastewater containing sodium sulfate, etc. was generated.

Na ₂ MoO ₄ + (NH ₄ ) ₂ MoO ₄ + Na ₂ SO ₄ + NaVO ₃ + NH ₄ VO ₃ + 4R ₃ N + 6HCl ↔ 2R ₃ NH ₂ MoO ₄ + 2R ₃ NHVO ₃ + 3NaCl + 3NH ₄ Cl + Na ₂ SO ₄ ... (7)

The solvent was then regenerated with R ₃ N and trace amounts of vanadium and molybdenum compounds were back extracted into aqueous solutions in the form of NH ₄ VO ₃ and (NH ₄ ) ₂ MoO ₄ , respectively.

R ₃ NH ₂ MoO ₄ + R ₃ NHVO ₃ +3 NH ₄ OH ₂ R ₃ N + (NH ₄ ) ₂ MoO ₄ + NH ₄ VO ₃ + 3H ₂ O. (8)

When back-extraction, the volume of the ammonia solution was reduced to 2 to 4 times. In the next molybdenum precipitation, the reaction time was short and the reaction efficiency was high. The concentrated solution was adjusted to pH 3.0 of the aqueous solution by adding hydrochloric acid or sulfuric acid to precipitate into (NH ₄ ) ₂ MoO ₄ (S) as shown in the formula (9).

(NH ₄ ) ₂ MoO ₄ ( ℓ ) ← pH adjustment [HCl (H ₃ SO ₄ )] → (NH ₄ ) ₂ MoO ₄ (S) + β. (9)

Where β is salt and water.

In the filtration / washing process, the vanadium adsorbed to (NH ₄ ) ₂ MoO ₄ (S) in formula (9) was lowered to 250 ppm by two washings, and the washed (NH ₄ ) ₂ MoO ₄ (S) was transferred to a drying furnace. The mixture was calcined at 500 ° C. for 2 hours to obtain high purity MoO ₃ . For reference, except for the 'solvent extraction / concentration II' process, when molybdenum precipitation was carried out in (B), about 10% of sodium was adsorbed to (NH ₄ ) ₂ MoO ₄ (S). After washing twice, the result was analyzed that sodium was about 5%, so that high purity MoO ₃ could not be obtained. The washed (NH ₄ ) ₂ MoO ₄ (S) was eluted, precipitated, and precipitated again by recrystallization to contain about 0.5% sodium. However, when the (solvent extraction / concentration II) process was carried out on the (b) flow, high purity MoO ₃ was obtained since the sodium adsorption amount became 0.02% or less.

In the process, the filtrate filtered with (NH ₄ ) ₂ MoO ₄ (S) was present in 0.2% or less of unreacted vanadium and molybdenum, and 'solvent extraction III' was performed to recover it. In other words, the extract was recycled in the same manner as in Schemes (1) and (2), and the extract was recycled to the 'solvent extraction / concentration I' process, and the ammonium chloride or ammonium sulfate wastewater of the extraction residue was generated as much as the filtrate. Thus, about 99% of vanadium and molybdenum water-leached were recovered. In addition, the ammonium wastewater generated in solvent extraction II and III was generated as much as the concentration of alkaline aqueous solution in solvent extraction I and II.

As such, specific embodiments of the present invention are as follows.

Molybdenum and vanadium content of 5% containing spent catalyst 5kg to 1.4kg tansa sodium and after mixing after 4 hours into the rotary kiln 950 ℃ roasting, followed by leaching for 30 minutes at 85 ℃ in 15 ℓ of distilled water to create a number of leachate first difference, Leaching again to prepare a secondary water leachate. The solvent diluted with 30% TIOA with kerosene was mixed with a separatory funnel and a shaker at mixing ratio of 1 min for 2 minutes and separation time of 30 min. Solvent extraction and back extraction were performed. Back-extraction of the concentrate is stylized each precipitation at pH 3.0 by using ammonium sulfate, hydrochloric acid or sulfuric acid in a _{(NH 4) 2 MoO 4,} pH 8.0 with NH ₄ VO _3, respectively, twice washed with 500 ℃ second time Drying in an electric furnace I was.

The figures in the table below are the values (ppm) of ICP analysis sampled at each process.

Table 1. 1st amount (in case of high concentration (b) flow)

Note n means not detected

In the table, the purity of V ₂ O ₅ and MoO ₃ was 99.0% and 99.7%, respectively, and the concentration ratio was about 1.8 times concentrated in Concentrate I and II, respectively, to 3.6 times the final concentration compared to the water leachate, and the ammonium wastewater was concentrated in Concentrate I and 45% reduction in II, resulting in a final 15% reduction in water leachate. The recovery rate was recovered by solvent extraction III in the case of the reaction after-treatment, so that only vanadium and molybdenum lost to the wastewater were lost, resulting in 99.7% recovery. The reaction efficiency increased as the remaining concentration of the reaction solution decreased, resulting in vanadium and molybdenum being 98% and 95%, respectively. That is, the higher the concentration, the greater the reaction efficiency at the same time compared to Tables 1 and 2 can be seen.

Table 2. Secondary Amount (For Low Density (A) Flows)

In the table, the purity of V ₂ O ₅ and MoO ₃ was 99.3% and 99.6%, respectively, and the concentration ratio was about 4 times higher than that of the water leachate in Concentrate I, and ammonium wastewater was reduced by 75% as the water leachate was concentrated 4 times. . The recovery was 99% because the vanadium falling into the wastewater was about 1%. The reaction efficiency was 92% and 60% for vanadium and molybdenum, respectively. In other words, the lower the concentration, compared to Table 1, 2 it can be seen that the reaction efficiency is reduced at the same time.

The invention As described above is to precipitate petrochemical waste catalyst such as a desulfurization catalyst, Nemo catalyst, Como catalyst, in the number of leach solution to a high temperature soda roasting, only vanadium and molybdenum components through solvent extraction and concentration of high purity V ₂ O ₅ and MoO ₃ can be effectively separated and recovered.

In the present invention, the vanadium and molybdenum components contained in the catalyst are not only continuously separated and recovered through solvent extraction, but also the highly concentrated hardly degradable ammonium wastewater generated after the precipitation process compared to the water leachate by the concentration method is 10 to 75. %, And the higher the concentration of vanadium and molybdenum, the higher the reaction efficiency in the synthesis of V ₂ O ₅ and MoO ₃ . In addition, since only vanadium and molybdenum components are selectively extracted during solvent extraction, the purity of V ₂ O ₅ and MoO ₃ can be increased by 99% or more, and the low concentration of vanadium and molybdenum remaining in the filtrate of the unsynthesized reaction solution can be extracted by the final solvent extraction. There are various advantages that can recover more than 99%.

Claims (4)

delete In a leachate containing soda-baked petrochemical waste catalyst containing vanadium and molybdenum, dilute the solvent TIOA in a volume ratio of 20 to 30% in kerosene as a diluent, and the volume ratio of the solvent to the leachate, ie, O / A (Organic / Aqueous). The solvent extraction method characterized in that vanadium and molybdenum can be selectively extracted under normal temperature and atmospheric pressure with 2 steps of mixing stage, 2 minutes or less mixing time and 10-30 minutes of layer separation time. delete delete

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