JPS6241716A - Treatment of used vanadium-containing catalyst - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) This invention relates to rare earth metal processing technology, particularly to a method for recovering vanadium from ores and industrial waste, and particularly to a method for processing spent vanadium-containing catalysts. .

As is well known in the art, vanadium is used in the ferrous metallurgy, non-ferrous metallurgy, and chemical industries in the production of vanadium steel alloys. Vanadium's use is widespread in the nuclear industry and other industrial fields. <It's growing.

Alloys of vanadium with titanium, chromium, cerium, aluminum and silicon are essential in tool making, power engineering and rocket technology.

Significant quantities of vanadium are used for the production of catalysts used in the production of sulfuric acid. The production of sulfuric acid is present in all establishments of the chemical industry and nonferrous metallurgy, since the exhaust gas contains anhydrous sulfurous acid, which is converted to sulfuric acid.

In the course of the action of vanadium catalysts, their catalytic activity decreases due to the accumulation of harmful substances and recrystallization of the carrier. This limits the lifetime of such catalysts, which is no more than 6 to 12 months. The spent catalyst contains approximately 5% vanadium pentoxide, which has no further use and is discarded as industrial waste.

As the production of sulfuric acid increases, so does the amount of spent vanadium catalyst produced each year. These wastes are accumulating, occupying valuable space, and contaminating the environment with toxic vanadium compounds.Due to the industry's strong demand for vanadium, its scarcity, high production costs and waste containing vanadium. Considering the prevention of environmental pollution, the urgency of the problem of reprocessing spent vanadium-containing catalysts into useful products becomes very clear.

Methods for the treatment of spent vanadium-containing catalysts are of great interest in many applications and are used, for example, in the production of vanadium catalysts, sulfuric acid and the preparation of pure vanadium pentoxide.

(Prior Art) Conventional methods for the treatment of spent vanadium-containing catalysts can be divided into hydrometallurgical methods and pyrometallurgical methods.

Hydrometallurgical methods can be classified into acidic methods and alkaline methods.

Method of acid elution under reduced conditions (USSR inventor Shiya 16
90750LB01J11/66. Published in 1965) can be considered effective for the treatment of spent vanadium catalysts.

Also known in the art is a process for treating spent vanadium catalysts consisting of elution in the presence of a reducing agent (sulfur dioxide) to reduce vanadium (V) to vanadium (5). A solution containing VO3O4k is, for example, M
Modified by n01, vanadium in the solution is p
) IO, 5 to 5.0 in a non-aqueous organic solvent. Vanadium is extracted from the extract, e.g.
Re-extracted with alkaline earth metals such as OH or NH,OH. A solution of ammonium vanadate is neutralized by sulfuric acid to form a precipitate of vanadium pentoxide [
08SR Inventor Certificate J1i178626,0LOOIG
31100. Published on May 15, 1979).

This prior art has the disadvantage that firstly only one thing is extracted, namely vanadium pentoxide and no other valuable ingredients such as potassium and aluminum sulfate are used as carriers for the acetic acid catalyst. has.

Second, the use of all sulfur pentoxide as a reducing agent in the elution stage prolongs the entire process (4-5 hours) and further pollutes the environment due to the release of sulfur dioxide.

Third, the re-extraction prescribed in this method results in incomplete recovery of vanadium from the organic phase and the final product is contaminated with low levels of vanadium oxide.

Fourth, the precipitation of vanadium pentoxide in this process leads to significant loss thereof, contamination of the final product and formation of large amounts of mother liquor required for use.

Therefore, the prior art does not guarantee a high recovery of vanadium into the desired product and regeneration of the support is not possible;
It is not possible to produce highly pure vanadium pentoxide, and it is also not possible to reduce water consumption and R environment pollution.

Consumption Known alkaline treatment methods for vanadium catalysts include treating the catalyst with alkali NaOH or KO in the presence of hydrogen peroxide.
Including treatment such as refluxing using H (Japanese Patent J￥
4321870,0LBOIJ, published 1968, Bulgarian Patent Office 14904.0L022B 34/22.
1971 Hand Issued Romania Patent No. 78284. C.L.
001G31100, published in 1982).

This method has the following drawbacks: These problems include the fact that the consumption rate of alkali to neutralize the acidity of the catalyst is low (increasingly high consumption rate), the loss of support due to alkali and its regeneration is impossible, and the obtained vanadium pentoxide is of low quality. .

Among the pyrometallurgical methods of treatment of spent vanadium catalysts, the document "5teel Tyrnes =, 1981.2
09. A Xi, P.P.

619-621's "Note or Vanacifu"
m A11oys 'f should be raised. This method fuses spent vanadium catalyst with potassium carbonate and potassium chloride, and elutes and recovers polyvanadate. However, this is characterized by a narrow treatment range of the starting catalyst, a low rate of regeneration and a poor quality of the vanadium pentoxide obtained.

Therefore, there is currently no process available for widespread application of spent vanadium-containing catalysts as useful products without wastewater and other emissions.

This invention makes it possible to fully utilize the spent vanadium catalyst as all valuable products, namely vanadium pentoxide, vanadium catalyst, aluminum-potassium aluminum sulfate and ammonium sulfate, thereby contributing to the reduction of environmental pollution. An object of the present invention is to provide a method for treating a vanadium-containing catalyst.

(Summary of the Invention) The object of the present invention is achieved by a method for treating a spent sodium-containing catalyst comprising the following steps.

(a) The spent vanadium-containing catalyst is eluted in the presence of a reducing agent that converts vanadium (■) to vanadium (IV) to form a bulb.

0) Separating the bulb obtained into a solution containing vanadium V) and a solid support.

(c) Vanadium in solution Qv)'t vanadium (
oxidizes to V).

(4) Extracting vanadium(V) from the solution obtained in step (c) with an aliphatic amine in a water-insoluble organic solvent to obtain an extract and a raffinate.

(e) Vanadium (V) ? by contacting the extract obtained in step (d) with an ammonia solution to form ammonium vanadate. Re-extract.

(f) Treating the ammonium vanadate obtained in step (e) with a sulfuric acid solution.

Here, according to the present invention, the elution of the used vanadium-containing catalyst in step Q) (,) is based on the weight of divalent vanadium (II) ions and divalent vanadium (V) ions contained in the spent vanadium catalyst. Ratio'i (0.6-0.7): 1. Keep it at Q,
It is carried out using divalent vanadium solution as reducing agent (
h) The solid support obtained in step (b) is treated with 4-5% of sulfuric acid upon boiling in live steam for 1-2 hours to form a bulb containing a hydrochemically active support. Treated with % liquid solution.

(i) The valve obtained in step (h) contains the sulfuric acid bath solution dispensed for elution in step (a) and the chemically activated fluid dispensed for the total preparation of the vanadium catalyst. Separate into f'L'fc carrier.

(k) Part of the solution obtained in step (II) after elution is used to obtain a solution of divalent vanadium (II),
100-300A at a temperature in the range of 15-50℃
Electrochemical treatment is performed by applying a current with a current density of /rrl.

The divalent vanadium(II) obtained is delivered to the elution step (,).

(II) The extraction of vanadium (V) in step (d) is carried out with an aliphatic amine in a water-insoluble organic solvent previously treated with sulfuric acid in a volume ratio of (35-40):1.

(e) In the re-extraction of vanadium <V> in step (e), the weight ratio of tetravalent vanadium (v) ions resulting from the partial reduction of ammonium persulfate and vanadium (V) in the extract is (0,5 ~3) In the presence of ammonium persulfate, while maintaining the relationship of 1 to 1, an aqueous phase containing an organic phase and solid ammonium vanadate was completely formed.

(n) The organic phase obtained in the re-extraction step (II) is distributed to the extraction step (d), and the aqueous phase containing solid ammonium vanadate is delivered to a filtration means.

(,) Filtration of ammonium vanadate was carried out until its residual water content was 50 to 60 x. As step 3, a solution of sulfuric acid is passed through to obtain a solution of vanadium pentoxide and ammonium sulfate.

(p) The raffinate after total extraction of vanadium in step (d) is evaporated to crystallize aluminum-potassium sulfate.

(r) The solution obtained in step (0) is completely evaporated to crystallize ammonium sulfate.

The solution fed to the electrochemical treatment step is the divalent vanadium CI! contained in the spent vanadium catalyst after the electrochemical treatment and after circulation to the extraction step (a). >The weight ratio of ions and divalent vanadium (V) ions is 0.6 to 0.7
: It is preferable to set it as 1. This weight ratio results in a more effective reducing action.

In order to extract vanadium with a high partition coefficient, it is desirable to carry out the extraction of vanadium using a tertiary aliphatic amine such as a trialkyl amine, which improves the recovery rate of vanadium.

The extraction of vanadium (V) is preferably carried out in a water-insoluble organic solvent by using an aliphatic amine pretreated with 60-70% strength sulfuric acid. At such a concentration of sulfuric acid, the extraction ability of aliphatic amines is retained for a long time, and the extraction condition is improved.

The method according to the invention makes it possible to use spent vanadium catalyst extensively and without waste. This method makes it possible to obtain useful products such as vanadium pentoxide, vanadium catalyst, aluminum-potassium alum, ammonium sulfate by a simple process characterized by a closed system, with a low energy consumption rate. .

Furthermore, the method of the present invention does not involve the formation of any waste water, thereby contributing to less pollution of the environment.

Another important advantage of the method of this invention is that vanadium is
．． It fully guarantees high recovery rates reaching 95-99% as the desired product at 6% purity, which far exceeds the typical yield obtained by conventional methods.

These and other advantages of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings showing the main flowcharts for the treatment of spent vanadium-containing catalysts.

DETAILED DESCRIPTION OF THE INVENTION A spent vanadium catalyst, generally comprising vanadium (IV) and (V), a silicate carrier, sulfur salts of potassium and aluminum, is subjected to an elution step in the presence of a reducing agent. . This is due to the fact that vanadium (V) has a lower solubility as a reducing agent than vanadium (IV). The introduction of a reducing agent in the elution step reduces the vanadium(V) to soluble vanadium(s) and allows for a more complete recovery of all the vanadium contained in the spent vanadium catalyst.

In the method of this invention, the elution step 1 is first carried out in the presence of a reducing agent, divalent vanadium (the weight ratio of mobile ions to divalent vanadium (V) ions is 0.
Divalent vanadium (II) ions maintained at 6-(II, 7: 1) are used.The elution step is carried out at 80~
Stirring is carried out for 30-60 minutes at a temperature within the range of 90°C.

By using divalent vanadium (II1> ion) as a reducing agent, almost all of the vanadium (V>k) can be recovered to reversible vanadium (IV), and almost all of the vanadium (IV) contained in the spent catalyst can be recovered. of vanadium can be converted into a solution.This is because vanadium 01
) is due to the fact that the redox potential ψV ''=-0.25 V is more negative compared to reducing agents such as sulfur dioxide, shialic acid and sodium sulfide. Therefore, vanadium(II) It is a more effective reducing agent for vanadium(V), ensuring more complete recovery of vanadium from the catalyst.

The reduction reaction is expressed by the following formula.

V, OB+VSO, +2HsSO4,3VO8O4+2
Additionally, the use of vanadium(II) ions shortens the duration of the elution step, which lasts 30-60 minutes due to its strong action.

Divalent vanadium (II) contained in the above-mentioned spent catalyst
) ions and divalent vanadium (v) ions depends on the following factors: Lower limit of ratio V [I): V (V) = 0
6:1 is sufficient to recover vanadium into solution at a level of 97-98% in 30 minutes. Ratio VQ[):■(
7) is less than 0.6:1, it is insufficient to completely recover vanadium. Ratio Veil: V(V)k
If the ratio exceeds 7:1, vanadium (@) which suppresses the reaction of the solution will be generated in the solution, which is not preferable.

By performing elution in the presence of divalent vanadium (II) ions, it is possible to simultaneously remove attached harmful substances from the spent catalyst carrier, thereby preparing the entire carrier for reuse in the production of vanadium catalysts. becomes.

The bulb obtained in elution step 1 is made of vanadium
a solution containing potassium and aluminum sulfate,
In step 2, the carrier is filtered and separated, and the carrier is delivered to step 3. In step 3, the carrier is heated with live steam to
Treat with 4-5% sulfuric acid solution while boiling for 2 hours. This ensures the gelation of the silica due to the increased surface area due to the formation of a localized vapor phase.

The characteristic area of the carrier amounts to 12-16, IIl.

The specified concentration lf of the sulfuric acid mentioned above is determined by the fact that high values of the specific area of the support cannot be achieved if the support is treated with solutions of sulfuric acid with a concentration below 4% or above 5%. There are n.

Regarding the treatment time of 1 to 2 hours mentioned above, if it is less than 1 hour, it is insufficient to obtain a highly developed surface of the carrier, and if it is more than 2 hours, the p-sulfuric acid is diluted by live steam, that is, the solution concentration exceeds the range. This is determined by the fact that this results in an undesirable range.

Therefore, the removal of adhering harmful substances from the support in elution step 1 and the increase in the unique surface area in step 3 make the support suitable for reuse in the production of vanadium catalysts.

Such carriers are hereinafter hydrochemically activated -C
It is said that there is.

The valve produced in step 3 is delivered to step 4,
The filtered A7j solution is then fed to elution step 1, while the hydrochemically active support is sent to step 5 for preparing the vanadium catalyst by mixing it with the active component.

The vanadium catalyst (Km OV* OS is n80m) manufactured as a total base of hydrochemically active support.
) is more active and heat resistant than conventional catalysts.

child'! 1. C. After the elution step 1, the support contains only a trace amount of vanadium, which has a promoting effect and improves the activity and heat resistance of the final catalyst.

Reuse of carriers operated for 6 to 12 months at temperatures in the range of SOO~650 °C can be achieved by reusing naturally occurring silica conglomerate [dia
tomite). This is because it eliminates the need for operations such as heat treatment, granulation, and crushing that are essential when using silica conglomerate.

A portion of the solution of vanadium obtained in step 2 is delivered to electrochemical treatment step 6 to obtain divalent vanadium (II) ions. This treatment is carried out at a temperature of 15-50° C. by applying a current with a current density of 100-300 A//. Under these conditions, vanadium(I) is reduced to vanadium(II). Step 6-C The resulting solution and vanadium(II) are delivered to elution step 1.

If the current density for the electrochemical treatment of the solution in step 6 is less than 100 V-, the duration of the reduction step will be significantly extended, while a current density of 300 A/' or more will lead to an undesirable power consumption rate. To increase.

As mentioned above, the solution obtained by the electrochemical treatment in step 6 and the divalent vanadium ions contained are delivered to the elution step, where the vanadium(II> ions are reduced to vanadium(V) ft vanadium(IV) It is used as a reducing agent for

The amount of binding solution delivered from Step 2 to Step 6 is such that the specific weight ratio of ions of divalent vanadium (II) and divalent vanadium (v) in Step 1 is 06 to 0.7:1. are selected as such.

The use of the vanadium (II) solution obtained in step 6 as the reducing agent in elution step 1 saves the consumption of reactants, prevents contamination of the final product and closes the production flow chart. enable.

Most of the solution of vanadium obtained in step 82 is delivered to step 7, where it is treated with an oxidizing agent such as potassium persulfate, potassium permanganate, and then the solution is delivered to extraction step 8. In step 7 the vanadium carrier is oxidized to vanadium(IV). This oxidation means is necessary for recovery in the extraction step 8.

Extraction of vanadium in step 8 is carried out with a tertiary aliphatic amine such as a trialkylamine in a water-insoluble organic solvent.

This mixture of amine and solvent is pretreated with sulfuric acid in a volume ratio of 35-40:1, respectively. The concentration of the sulfuric acid solution can vary over a wide range from 5 to 70%, but the most preferred concentration is 60 to 70%.

The use of an extractant pretreated with sulfuric acid ensures the formation of a stable, homogeneous and physically difficult to separate organic phase.

Total treatment of the extractant with sulfuric acid at ratios below 351 deteriorates the homogeneity of the extractant after a few hours and a solution of sulfuric acid develops from it, whereas at ratios above 40:1 the organic phase carbonizes and the extraction The result is that the agent decomposes.

The previously described means of pre-treating the extractant with sulfuric acid in a volume ratio of 35-401 ensures an almost complete extraction of vanadium(V)'r from the solution into the organic phase.

In extraction step 8, an extract and a raffinate are obtained. The extract is fed to a re-extraction step 9 and the raffinate to an evaporation step 10.

Vanadium (V) is re-extracted by contacting the extract with an ammonia solution and adjusting the weight ratio of ammonium persulfate to vanadium ions contained in the extract from 0.5 to 3:
This is done by introducing ammonium persulfate while maintaining the temperature at 1. The vanadium (M) in the extract is produced by partial reduction by the vanadium (V) ffi extractant.

The use of ammonium persulfate in the re-extraction step 9 allows the conversion of ammonium vanadate gold formation (7) to vanadium(V) according to the following reaction equation.

2VO""-8t O--+ 6NH4+H*0-+2
Nru: N(% + 2(NH4)s so4 +8H
``The conditions for the re-extraction of vanadium (V) make it possible to obtain ammonium vanadate in the form of a solid product with a well-formed large crystalline structure.

The ammonium vanadate produced is vanadium(y)
compounds, thus constituting the desired product of high quality.

Ammonium vanadate, which has a large crystal structure, is easily recovered from the organic phase and is not localized at the interface, resulting in a short layer formation period and complete extraction of vanadium in a single step.

Said specific ratio of ammonium persulfate (NH4)z St Oa to vanadium (ro) of 0.5:1 is both sufficient and necessary. If this ratio is decreased, the oxidation of vanadium (co) to vanadium (y) will be incomplete,
The recovery of vanadium to the desired product is low, resulting in incomplete structure of ammonium vanadate in the formation of emulsions and prolonged phase separation time. Increasing the ratio of ammonium persulfate to vanadium (V) to 3:1 or more is not preferable because the salting-out effect of ammonium persulfate causes deterioration of the structure of ammonium vanadate.

The organic phase obtained in the re-extraction step 9 is delivered to the extraction step 8, while the aqueous phase containing solid ammonium vanadate is delivered to the filtration step 11.

The filtration of the aqueous phase containing solid ammonium vanadate is carried out such that the residual water content of the ammonium vanadate is 50-60%, and the weight ratio of the acid to the vanadium contained in the ammonium vanadate is 1.2-60%. A sulfuric acid solution is passed through the residual layer of ammonium vanadate in a ratio such that: By this method, vanadium (V)
Possibility of conversion to '! r, providing conditions for minimum solubility of the vanadium pentoxide formed, which guarantees to obtain a high quality final product and to convert ammonium vanadate to vanadium pentoxide with sufficient loss. .

The residual moisture limit of ammonium vanadate mentioned above is
It is based on the fact that the quality of the vanadium pentoxide obtained is impaired when the residual moisture is less than 50% or more than 60%.

If the ratio of sulfuric acid to vanadium is less than the lower limit mentioned above, it will lead to incomplete conversion of ammonium vanadate to vanadium pentoxide and its loss; if it exceeds the upper limit mentioned above, it will lead to an increase in the consumption rate of sulfuric acid and a loss of the final product. This is not preferable because it causes contamination by SO4 ions.

The vanadium pentoxide obtained in step 11 is delivered to melting step 12. Molten vanadium pentoxide is 99.9%
The main ingredient is Kanakura Mi, making it a high quality product.

The mother liquor obtained in step 11, free of impurities and containing only ammonium sulfate (the impurities are removed in extraction step 8), is delivered to step 13, where it is evaporated and crystallized as commercial ammonium sulfate.

The raffinate produced in extraction step 8 and delivered to step 1o is evaporated and crystallized to obtain aluminum-potassium alum. The production of alum in step 1o is as follows:
This is made possible by extracting potassium and aluminum from the effluent under the conditions of elution step 1.

The condensate obtained in steps 10 and 13, which mostly contains only water, is recovered and delivered to step 3 (not shown).
.

Therefore, the process for treating spent vanadium catalyst of the present invention is a closed system and allows for the complete production of products such as vanadium pentoxide, vanadium catalyst, aluminum-potassium alum and ammonium sulfate. The method of the invention contributes to the protection of the environment since the generation of waste water can be avoided.

In order to more fully understand this invention, some specific examples are provided below which illustrate methods for treating spent vanadium-containing catalysts used in sulfuric acid manufacturing processes. All symbols shown in the attached drawings shall be used.

Example 1 In positive sign %, vanadium (ff) 2.39, vanadium (V) 1.02, aluminum 30. Potassium 12.
71 + S l0x59.8. 1.71 of the spent vanadium catalyst containing SoP-2108 and small additives,
Bathing is performed in step 1 with the recovered liquid recovered from step 4, with a ratio of solid phase to liquid phase (S:L) of 1:3. 8.26 from step 6 as reducing agent in step 1
t/L of vanadium (1.26-6 liquids containing cup ions) are used.

The ratio of vanadium (II) to vanadium (V) contained in the initial spent catalyst is equal to 0.6:1. The elution step is carried out at a temperature of 80-90°C for 30 minutes.

The resulting bulb is filtered in step 2 and has a concentration of 9.96
Vanadium (F/) in f/l, 5.35? A liquid containing 6.80 f/l of aluminum and 25 f/l of potassium
Tfl and weight percent vanadium 0.15, aluminum 1.29, force') ram 4.03. S
A carrier containing iOm 90.05 and 804-''4.4 f yields t,ia.

The recovery rate of vanadium in step 1 is 97%.

1.13 t of carrier was separated in step 2 and delivered to step 3 where it was boiled with live steam for 1-2 hours.
Treated with 5.54% sulfuric acid solution. The obtained pulp was filtered in step 4, and a solution containing 14% sulfuric acid, 0.2 Vt vanadium was 6.8 m', weight percent vanadium 0.03, fluminilum 1.29,
Potassium 4.03.5iO190.05 and Boa-”
4.6 The hydrochemically active carrier containing 1.13
1 is obtained.

The surface area of the hydrochemically active carrier is 12 cm.

The solution of 6B- is delivered to elution step 1.

1.13 t of hydrochemically active carrier is thoroughly mixed with the carrier and active ingredient, chaped and dried,
and step 5 to produce vanadium catalyst by calcination.
will be delivered to. As a result, the chemical formula Ks 0-Vx Os
A vanadium catalyst of 1,651 is obtained with an activity of 89.6% at 485° C. and 366% at 420° C., expressed as 50 g to Si. Catalyst safety testing (So,
The activity is 89.4% at 485°C and 36.4% at 420°C.

A portion of the solution obtained in step 2, 1.26+1/, is delivered to step 6 of the electrochemical treatment, at a temperature of 40° C. in the cathode space of the membrane-type device, at a current density of io.

The treatment is carried out by applying a full current of 1000 ml to vanadium (IV) until vanadium (IV) is completely reduced to vanadium (II). Power consumption rate is 1.25 per II of vanadium pentoxide recovered
KW/hr. After electrochemical treatment, 9.96f/
A solution containing 1 of vanadium(II) imene is delivered to elution step 1.

The bulk of the solution obtained in step 2 5.54- is delivered to step 7 where potassium persulfate Kg St Os 't
” Using 40Kf to convert vanadium (IV) to vanadium (
V).

9.96 f/l vanadium (V), s, 3sy
The 554 t.l solution obtained in step 7 containing 32229/l aluminum and 32229/l potassium is delivered to extraction step 8 for vanadium(V)'k extraction. As an extractant, the volume ratio of extractant to sulfuric acid is 4.
C4 pretreated with a 60% solution of sulfuric acid at 0:1
A 0.4M solution of a trialkylamine with a mixture of higher primary in-alcohols having chains of . , .about.CI4 is used. Such extractant mixtures containing sulfuric acid are homogeneous and difficult to physically separate. The extraction is carried out in three stages by a countercurrent method with a volume ratio of aqueous phase to organic phase A:O'i of 3:1. After extracting vanadium in step 8, 0.083 t/L of vanadium(V), 5.3
5t/l (D aluminum, 5.54#/ raffinate containing 32.22t/l potassium, and 2923?/l
l vanadium (V) and 0.5 ? 1.84 m' of extract containing vanadium/l is obtained.

The recovery rate of vanadium in step 8 is 99.18%.

The extract of 1,84- obtained in step 8 is delivered to re-extraction step 9 where the extract is treated with 5% ammonia solution 061
- and ammonium persulfate and vanadium (F
7) 0.46Kg corresponding to a ratio of 0.5:1 with ions
ammonium persulfate.

Re-extraction 1i at 60°C for 10 minutes. Re-extraction step 9
Vanadium is oxidized to vanadium (+/) in the gas, and the organic compound of vanadium is decomposed to produce solid ammonium vanadate containing 54.17 ~ vanadium. It is formed with an organic phase consisting of a mixture of iso-alcohols.

The system formed in the re-extraction step 9 is capable of forming organic, aqueous and solid phase components.

The recovery rate of vanadium is 99%.

The 1,84- organic phase obtained in step 9 is delivered to extraction step 8.

Bar 3 - Ammonium vanadate containing 4 in 54.17 is filtered in step 11 to a residual moisture content of 50%. The weight of wet ammonium vanadate is 248.55k, while the volume of mother liquor containing ammonium sulfate is 0.415+♂.

187 tons of 60% sulfuric acid are passed through the residue obtained in step 11 - ammonium vanadate. The ratio of sulfuric acid to vanadium in ammonium vanadate is 1:3. The obtained vanadium pentoxide hydrate is 5
Contains 9 vanadium in 4.09.

The recovery of vanadium as vanadium pentoxide in step 1iKz- is 99.8%, ie almost no loss of vanadium due to the mother liquor is observed.

The mother liquor obtained in step 11 and containing ammonium sulfate is delivered to step 13 where it is evaporated and crystallized to obtain ammonium gold sulfate consisting of: 98% of (N1(4
)t 804, water-insoluble residue - 0,05%, residue after calcination - 0,05%, Fe - 0,01%, Pb - not detected, As - not detected. In this way, it corresponds to the purity of the product.

The condensate obtained after the evaporation step 13 to obtain ammonium sulfate is delivered to step 13 (not shown).

The vanadium pentoxide obtained in step 1j is delivered to melting step 12. The fc fused vanadium pentoxide formed is VtOs 99.5%, V, 0. -0.4
%, NHa=-0,os%, 80. -0.
01%, Na+KO, 04%, which corresponds to a high quality product. The direct recovery rate of vanadium by this method is 95.5%.

The raffinate formed in extraction step 8 is delivered to step 10 where it is evaporated to give AtK (
804) t ・l 2L 096%, NH4”-o,
ot%, Fe-0,02%, water-insoluble residue-0,0
An aluminum-potassium alumium of commercial quality consisting of 1% is crystallized.

The condensate after evaporation is delivered to a finger treatment facility 83 (not shown).

Example 2 The spent vanadium catalyst in Step 1 was bathed out at a weight ratio of divalent vanadium ions to five vanadium ions of 0.
7: The process is carried out in the same manner as the 9 method described in Example 1 above, except that it is maintained at 1.0. The recovery rate to vanadium 't-G liquid is 980%.

The support in step 3 is treated with a 5% solution of H,So. The surface area of the hydrochemically activated friend carrier is 1
6n? /f.

The electrochemical treatment of the vanadium solution in step 6 consists of 4
The test is carried out by applying a current with a current density of 200 υ at a temperature of 5°C. The power consumption rate per 1 vanadium pentoxide is 1.28 KW/br.

The extraction of vanadium (V) in step 8 is carried out at a volume ratio of 35
:High grade No. 1 pretreated with 70% HtSO* of 1
It is carried out using a 0.4M solution of trialkylamine in a mixture of iso-alcohols. The recovery rate of vanadium is 99.1%.

The re-extraction of vanadium in step 9 is carried out in the presence of ammonium persulfate in which the weight ratio of ammonium persulfate to vanadium (F/) ions contained in the extract is maintained at 2.0:1. Processing time for this step was reduced to 5 minutes. Under the conditions of Example 2, the direct recovery rate of vanadium pentoxide was improved to 95.8%.

The components of the product produced are similar to those of Example 1O described above.

Example 3 The method was carried out as described in Example 1 with the difference that the electrochemical treatment of the vanadium solution in step 6 was carried out at a temperature of 50° C. and by applying a current with a current density of 30 OA. It will be done. The processing time is shortened, and the power consumption rate per 1 vanadium pentoxide is 1.32 KW/hr.

The re-extraction of vanadium in Step 9 is carried out in the presence of ammonium persulfate in which the weight ratio of ammonium persulfate to vanadium (fugitive ions) contained in the extract is maintained at 3:1.

The solid ammonium vanadate is filtered to a residual moisture content of 60% and the sulfuric acid solution is passed through the bed of the resulting residue such that the weight ratio of sulfuric acid to vanadium in the ammonium vanadate is 1:2.

The results are similar to those in Example 1 above. Pentoxide/(Nadium component is Vs Os 99.6%, v*Oi
0.3%.

NH4” 0.005%, 80.-2-0.0 i
%, Na+ is -0.04%.

The components of aluminum-potassium aluminum and ammonium sulfate are the same as in Example 1.

According to these embodiments, the method for the treatment of spent vanadium catalysts of the present invention can produce commercial products such as vanadium pentoxide, vanadium catalyst, aluminum potassium chloride, and ammonium sulfate without producing wastewater. can be obtained within a closed system. The method of this invention can be easily implemented on a commercial scale.

[Brief explanation of the drawing]

The accompanying drawing is a main flowchart showing the method for the treatment of spent vanadium-containing catalyst. 1- Step of eluting the spent catalyst 2- Step of separating the pulp into solution and carrier 3- Step of treating the carrier with sulfuric acid 4- Step of separating the carrier from the bath liquid 5- Step of separating the vanadium catalyst 6- Step of separating the solution Electrochemical treatment step 7 - Vanadium (b) oxidation step 8 - Vanadium ('/) extraction step 9 - Vanadium (V) re-extraction step 10 - Raffinate evaporation step 11 - Separation of ammonium vanadate Step 12 - Melting process of vanadium pentoxide 13 - Evaporation process of mother liquor containing ammonium sulfate Patent applicant representative Patent attorney Fumi Sato [and one other person] [Inventor] Tamerlan Soslan Soviet Union Tsvekovych Shish I 62・Kwarchinov■≧1 Inventor Gennady Konsta Soviet Union・Lantinowichta 22・Kolpstrabrin ■Inventor Vladimir Leo Soviet Union・Anidovich Bess 54・Kwarchiraman 0 Inventor Alexander Yako Soviet Union・Knowl °Itschi Bakae Cha 7 Kwarf (fi'J Inventor Tamara Vasilyevna
Soviet Union, Nomlina Nik 8 Kuwal Inventor: Tamara Vasilyev” Soviet Union, Nokholkovskik Kaya 25 Kuwal (m) Inventor V, Iktor Geol Soviet Union, Ogievitzchi Kuzmi Ilatova 4
9/2-La Urituza Revu Orjutuira 17
2 - La Uritsa Yu, Fuyucica Kwarčila 61 Rumaata Uritsa Satpaeva Vuosibirsk Uritsa Inotschyla 39 Vosibirsk Uritsa Učecila 69 Wosibirsk Uritsa Rusčila 54 Detsa Uritsa Academica Fu Kwarčila 35

Claims (1)

[Claims] 1. Consists of the following steps (a) to (f), and the following (g)
A method for treating a used vanadium-containing catalyst characterized by (r) (a) eluting the used vanadium-containing catalyst in the presence of a reducing agent for converting vanadium (V) to vanadium (IV), and pulping the used vanadium-containing catalyst; (mineral mud). (b) Separating the obtained pulp into a solution containing vanadium (IV) and a solid support. (c) Oxidize vanadium (IV) in the solution to vanadium (V). (d) Extracting vanadium(V) from the solution obtained in step (c) with an aliphatic amine in a water-insoluble organic solvent to obtain an extract and a raffinate. (e) Re-extracting vanadium (V) by contacting the extract obtained in step (d) with an ammonia solution to form ammonium vanadate. (f) Treating the ammonium vanadate obtained in step (e) with a sulfuric acid solution. (g) In step (a), the spent vanadium-containing catalyst is eluted by reducing the weight ratio of divalent vanadium (II) ions and pentavalent vanadium (V) ions contained in the spent vanadium catalyst to (0.6 ~0.7): carried out using a divalent vanadium solution as reducing agent to maintain the value of 1.0. (h) The solid support obtained in step (b) is dissolved in a 4-5% solution of sulfuric acid during boiling in live steam for 1-2 hours to form a pulp containing the hydrochemically active support. The pulp obtained in step (h) of (i) to be treated is
) is separated into a sulfuric acid solution delivered for elution and a hydrochemically activated support delivered to prepare the vanadium catalyst. (k) A part of the solution obtained in step (b) after elution is used to obtain a solution of divalent vanadium (II).
Electrochemical treatment was performed by applying a current with a current density of 100 to 300 A/m^2 at a temperature in the range of °C, and the resulting solution of divalent vanadium (II) was subjected to the elution step (a). Delivered. (l) The extraction of vanadium (V) in step (d) is
It is carried out with an aliphatic amine in a water-insoluble organic solvent previously treated with sulfuric acid in a volume ratio of (35-40):1. (m) The re-extraction of vanadium (V) in step (e) is carried out in such a way that the weight ratio of ammonium persulfate to tetravalent vanadium (IV) ions formed as a result of the partial reduction of vanadium (V) is (0.5 to 3). ): 1 in the presence of ammonium persulfate, forming an aqueous phase containing an organic phase and solid ammonium vanadate. (n) The organic phase obtained in the re-extraction step (e) is delivered to the extraction step (d) and the aqueous phase containing solid ammonium vanadate is delivered to a filtration means. (o) Filtration of ammonium vanadate is carried out until its residual water content is 50-60%, and the resulting layer of ammonium vanadate is coated with a weight ratio of sulfuric acid and vanadium in ammonium vanadate of 1:2. As ~3 pass a solution of sulfuric acid to obtain a solution of vanadium pentoxide and ammonium sulfate. (p) In step (d), the raffinate after extracting vanadium is evaporated to crystallize aluminum-potassium alum. (r) The solution obtained in step (o) is evaporated to crystallize ammonium sulfate. 2. A portion of the solution delivered to the electrochemical process is
In a), the weight ratio of divalent vanadium (II) ions to pentavalent vanadium (V) ions is the specific value, 0.6 to
3. Process 3 according to claim 1, characterized in that for extracting vanadium, a tertiary aliphatic amine is incorporated in an amount ensuring a ratio of 0.7:1. Method 4 according to claim 1, characterized in that the method is used as