JPS5814367B2 - Selective extraction method of molybdenum from desulfurization waste catalyst - Google Patents
Selective extraction method of molybdenum from desulfurization waste catalystInfo
- Publication number
- JPS5814367B2 JPS5814367B2 JP54078798A JP7879879A JPS5814367B2 JP S5814367 B2 JPS5814367 B2 JP S5814367B2 JP 54078798 A JP54078798 A JP 54078798A JP 7879879 A JP7879879 A JP 7879879A JP S5814367 B2 JPS5814367 B2 JP S5814367B2
- Authority
- JP
- Japan
- Prior art keywords
- molybdenum
- waste catalyst
- aqueous solution
- vanadium
- desulfurization waste
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Inorganic Compounds Of Heavy Metals (AREA)
- Manufacture And Refinement Of Metals (AREA)
Description
【発明の詳細な説明】
本発明は、重油の水添直接脱硫廃触媒中に含有されるア
ルミニウム、バナジウム、コバルト、ニッケル、モリブ
デン等の金属成分からモリブデン成分だけを高収率で選
択的に抽出する方法に関する。Detailed Description of the Invention The present invention selectively extracts only molybdenum components in high yield from metal components such as aluminum, vanadium, cobalt, nickel, and molybdenum contained in waste catalysts for hydrogenation and direct desulfurization of heavy oil. Regarding how to.
近年、重油の低硫黄化が公害防止対策上重要となり、水
添直接脱硫法が石油精製のさいに採用されている。In recent years, reducing the sulfur content of heavy oil has become important as a pollution prevention measure, and the direct hydrogenation desulfurization method has been adopted in petroleum refining.
この水添脱硫に使用する触媒は、脱硫される重油中のバ
ナジウム等の附着により触媒活性を失うので周期的に新
しい触媒と取替られる。The catalyst used for this hydrodesulfurization loses its catalytic activity due to adhesion of vanadium, etc. in the heavy oil being desulfurized, so it is periodically replaced with a new catalyst.
この際、発生する廃触媒中にはバナジウム、モリブデン
、コバルト、ニッケル等の有価金属が含有されているの
で、従来からこれら金属を回収する方法が種々提案され
ている。At this time, the waste catalyst generated contains valuable metals such as vanadium, molybdenum, cobalt, and nickel, and various methods have been proposed to recover these metals.
例えば、該廃触媒を酸化焙焼し才付着油分および硫黄分
を除去した後、苛性ソーダや炭酸ソーダ水溶液、あるい
はアンモニア水．弱酸のアンモニウム塩例えば炭酸アン
モン水溶液を抽出液として使用し、１００℃以上または
それ以下の温度で浸出する方法、または硫酸の如き強酸
による浸出法など、が提案されている。For example, the spent catalyst is oxidized and roasted to remove adhering oil and sulfur, and then treated with caustic soda, aqueous soda carbonate solution, or aqueous ammonia. A method of leaching using an ammonium salt of a weak acid, such as an aqueous ammonium carbonate solution, at a temperature of 100° C. or higher or lower, or a leaching method using a strong acid such as sulfuric acid has been proposed.
だが、これらの方法のうち、苛性ソーダあるいは炭酸ソ
ーダ水溶液で抽出する方法は、モリブデンがバナジウム
と共に抽出され、その抽出率も夫夫９０％程度であるが
、担体のアルミナが幾分溶出するため、その戸過性が非
常に悪く、工業的には等殊な庫価な戸過材を使用せざる
を得す、且つモリブデンとバナジウムの分離が煩雑であ
り、回収モリブデン酸の純度が悪く、その精製に手間が
かかると言う欠点がある。However, among these methods, the method of extraction with caustic soda or sodium carbonate aqueous solution extracts molybdenum together with vanadium, and the extraction rate is about 90%, but the alumina of the carrier is eluted to some extent. The passability is very poor, and industrially, it is necessary to use a special and expensive passthrough material, and the separation of molybdenum and vanadium is complicated, and the purity of recovered molybdic acid is poor, and its purification is difficult. The disadvantage is that it is time consuming.
また、アンモニア水、弱酸のアンモニウム塩例えば炭酸
アンモン水溶液で抽出する方法（例えば特開昭４９−８
４９１号公報に記載の方法）は、苛性ソーダ或いは炭酸
ソーダ水溶液で抽出する方法に比べ、そのＰ過性は良好
であり、モリブデン抽出率も９０％以上が得られるが、
バナジウムもある程度溶出することがさけられない。In addition, a method of extraction with aqueous ammonia, an ammonium salt of a weak acid, for example, an aqueous solution of ammonium carbonate (for example, JP-A No. 49-8
The method described in Publication No. 491) has better P permeability than the method of extraction with caustic soda or aqueous sodium carbonate solution, and can obtain a molybdenum extraction rate of 90% or more.
It is inevitable that vanadium will also be eluted to some extent.
さらに、硫酸の様な強酸による抽出法では、該廃触媒の
担体アルミナをも溶出するので、抽出液からモリブデン
、バナジウム等の有価金属を回収する際、先づ溶出して
いるアルミニウム分を例えばアルミニウム明ばんの様な
形で析出分離しなければならず、この際発生する大量の
アルミニウム明ばんの処理が問題となり、工業的には採
用不可能である。Furthermore, in the extraction method using a strong acid such as sulfuric acid, the carrier alumina of the waste catalyst is also eluted, so when recovering valuable metals such as molybdenum and vanadium from the extract, first the eluted aluminum is It must be precipitated and separated in a form similar to alum, and the treatment of the large amount of aluminum alum generated at this time poses a problem, making it impossible to adopt it industrially.
本発明はこれら従来法における諸欠点を排除して脱硫廃
触媒からモリブデン成分とバナジウム成分を高収率で工
業的に回収すること、特にモリブデンの高純度製品を得
るための該触媒からの上記両成分の有利な抽出法を開発
することを目的としてなされたものである。The present invention eliminates the drawbacks of these conventional methods and aims to industrially recover molybdenum and vanadium components from desulfurization waste catalysts in high yields, and in particular to recover the above-mentioned components from the catalysts in order to obtain high-purity molybdenum products. This was done with the aim of developing an advantageous extraction method for the components.
本発明者等は、この様な焙焼廃触媒の処理について種々
実験検討した結果、アンモニア水あるいは炭酸アンモン
水溶液に適量の硫酸アンモニウムを添加、溶解した水溶
液を用いて適当な条件下で抽出すると、該廃触媒中に含
まれる有価金属のうちモリブデンのみを９７係以上の高
率で抽出できその際バナジウムは殆んど抽出されず、す
なわちモリブデンのみの選択抽出が可能であることを見
い出した。As a result of various experimental studies regarding the treatment of such roasted waste catalysts, the present inventors have found that when an appropriate amount of ammonium sulfate is added and dissolved in ammonia water or ammonium carbonate aqueous solution and extracted under appropriate conditions, the It has been found that among the valuable metals contained in the waste catalyst, only molybdenum can be extracted at a high rate of 97 or higher, with almost no vanadium being extracted, that is, it is possible to selectively extract only molybdenum.
本発明は、かかる知見に基いてなされたものであり、脱
硫廃触媒を例えば５００ｄ以上の温度で空気と接触させ
て酸化焙焼して附着油分および硫黄分を除去し、ついで
得られた焙焼生成物を、アンモニア水とアンモニウム塩
、または２種以上のアンモニウム塩の水溶液中で、１１
０℃以上の温度、酸素あるいは空気吹込みによる１ｋｇ
／ｃｒＡ以上の酸素分圧のもとで、加圧浸出処理するこ
とによって該焙焼生成物中の金属成分のうちモリブデン
成分を選択的に抽出することを特徴とする。The present invention has been made based on this knowledge, and the desulfurization waste catalyst is brought into contact with air at a temperature of, for example, 500 d or more, oxidized and roasted to remove adhering oil and sulfur, and then the resulting roasted The product was dissolved in aqueous ammonia and an ammonium salt, or in an aqueous solution of two or more ammonium salts for 11 hours.
1kg at a temperature above 0℃, oxygen or air blowing
It is characterized by selectively extracting the molybdenum component among the metal components in the roasted product by pressure leaching treatment under an oxygen partial pressure of /crA or higher.
ここで、浸出液は、好ましくはアンモニア水または炭酸
アンモン水溶液に硫酸アンモニウムを溶解したものであ
る。Here, the leachate is preferably a solution in which ammonium sulfate is dissolved in aqueous ammonia or aqueous ammonium carbonate solution.
以下、本発明の内容につい詳しく説明する。The contents of the present invention will be explained in detail below.
本発明は脱硫廃触媒をあらかじめ５００℃以上の温度で
空気と接触させて焙焼することが必要であるが、その焙
焼温度については次の浸出工程におけるモリブデンの抽
出率に悪影響を及ぼさないので、廃熱回収の点からはな
るべく高い温度が好ましい。In the present invention, it is necessary to roast the desulfurization waste catalyst in advance by bringing it into contact with air at a temperature of 500°C or higher, but the roasting temperature does not adversely affect the extraction rate of molybdenum in the next leaching process. From the viewpoint of waste heat recovery, the temperature is preferably as high as possible.
７５０℃附近からモリブデン成分である三酸化モリブデ
ンの昇華が始まるが、この昇華したモリブデン成分を回
収し得る設備すなわち焙焼排ガスの熱回収設備例えばボ
イラーの後にサイクロンコットレルあるいはスクラバー
等の設備を設置すれば特に問題はない。Sublimation of molybdenum trioxide, which is a molybdenum component, begins at around 750°C, but if equipment that can recover this sublimated molybdenum component, that is, heat recovery equipment for roasting exhaust gas, is installed, for example, equipment such as a cyclone Cottrell or a scrubber after the boiler. There are no particular problems.
焙焼時間についても特に問題はなく、該廃触媒中の各種
有価金属がそれぞれ最高原子価の酸化物、例えばモリブ
デン成分はＭｏ０３、バナジウム成分は■２０５になる
様に選択すれば良く、数時間以下の焙焼で充分である。There is no particular problem with the roasting time, and the roasting time can be selected so that the various valuable metals in the waste catalyst have the highest valence oxides, such as Mo03 for the molybdenum component and ■205 for the vanadium component, and the roasting time is several hours or less. Roasting is sufficient.
上述の様にして得られる廃触媒の焙焼生成物は次いでア
ンモニア水或いは炭酸アンモン水溶液に適量の硫酸アン
モニウムを溶解させた水溶液を用いて加圧浸出する。The roasted product of the spent catalyst obtained as described above is then leached under pressure using an aqueous solution in which an appropriate amount of ammonium sulfate is dissolved in aqueous ammonia or an aqueous ammonium carbonate solution.
使用するアンモニア水或いは炭酸アンモン水溶液のアン
モニア濃度は、特に臨界的ではないが、焙焼生成物中に
含まれるモリブデン量に対し１．０化学当量以上であれ
ばよく、でき得れば２ないし３当量程度が好ましい。The ammonia concentration of the ammonia water or ammonium carbonate aqueous solution used is not particularly critical, but it may be at least 1.0 chemical equivalent, preferably 2 to 3, relative to the amount of molybdenum contained in the roasted product. Equivalent amounts are preferred.
添加する硫酸アンモニウムの濃度は焙焼生成物中に含ま
れるバナジウム量に対し７当量以上が好ましい。The concentration of ammonium sulfate added is preferably 7 equivalents or more based on the amount of vanadium contained in the roasted product.
反応温度は１００℃以上であれば良いが、反応時間の短
縮を企る為には１１０℃以上、さらに好ましくは１２０
℃以上とすればよい。The reaction temperature may be 100°C or higher, but in order to shorten the reaction time, it should be 110°C or higher, more preferably 120°C or higher.
The temperature may be set to ℃ or higher.
この条件下では浸出反応は短時間で終了するので反応時
間は１時間程度もあれば充分である。Under these conditions, the leaching reaction is completed in a short time, so a reaction time of about 1 hour is sufficient.
反応圧力は酸素分圧１ｋｌ／ｃ！２以上が好ましい。The reaction pressure is oxygen partial pressure 1kl/c! 2 or more is preferred.
本発明によると、該脱硫廃触媒から、担体であるアルミ
ニウム成分を全く溶出せずにモリブデン成分を９７係以
上の高収率で浸出し、しかもバナジウム成分を殆んど浸
出させないことが可能であり、従って後処理すなわちモ
リブデン精製工程が非常に簡単になると言う有利性を有
する。According to the present invention, the molybdenum component can be leached from the desulfurization waste catalyst at a high yield of 97 coefficients or higher without eluting the aluminum component, which is the carrier, and the vanadium component can hardly be leached out. , which therefore has the advantage that the after-treatment, ie, the molybdenum purification step, becomes very simple.
また、上述の加圧浸出工程より出るスラリーは非常に沖
過性がよく、通常工業的に広く用いられるドラムフィル
ター或はフィルタープレス等の沖過機により容易に戸過
、洗滌し得ることも本発明の利点である。It is also true that the slurry produced from the pressure leaching process described above has very good permeability and can be easily filtered and washed using a permeable filter such as a drum filter or filter press that is commonly used in industry. This is an advantage of the invention.
かくして得られたモリブデン含有アンモニア性水溶液は
必要なら一部を加圧浸出原液として繰り返すことによっ
て含有モリブデン濃度を高くすることも可能である。If necessary, a portion of the molybdenum-containing ammoniacal aqueous solution thus obtained can be repeatedly used as a pressurized leaching stock solution to increase the molybdenum concentration.
この水溶液からのモリブデン回収方法としては公知の方
法すなわち硫酸等の強酸を該水溶液に添加することによ
ってそのｐＨ値を３程度に調整することにより含有モリ
ブデン成分をモリブデン酸として析出沈でんさせて分離
し、該モリブデン酸をアンモニア水に溶解させて、三級
アミンを用いる溶媒抽出法により一挙に化学品純度のパ
ラモリブデン酸アンモンを回収することが可能である。A known method for recovering molybdenum from this aqueous solution is to add a strong acid such as sulfuric acid to the aqueous solution, adjust the pH value to about 3, and separate the molybdenum component by precipitation as molybdic acid. It is possible to recover ammonium paramolybdate of chemical purity all at once by dissolving the molybdic acid in aqueous ammonia and performing a solvent extraction method using a tertiary amine.
更にモリブデンを浸出した残渣からのバナジウム成分の
回収方法としてはこれまた公知の方法すなわち苛性ソー
ダ水溶液を用いてバナジウム成分を抽出し、得られたバ
ナジウム含有水溶液に硫酸等の強酸を添加することによ
って、そのｐＨ値を１程度に調製することにより、含有
バナジウム成分を五酸化バナジウムとして析出沈でんさ
せて分離し、沈でん物を乾燥するだけで市販純度の五酸
化バナジウムを回収することが可能である。Furthermore, as a method for recovering the vanadium component from the residue from which molybdenum has been leached, the vanadium component is extracted using a caustic soda aqueous solution, and a strong acid such as sulfuric acid is added to the obtained vanadium-containing aqueous solution. By adjusting the pH value to about 1, commercially pure vanadium pentoxide can be recovered by simply separating the contained vanadium component by precipitation as vanadium pentoxide and drying the precipitate.
さらに、本発明によると、バナジウムの浸出残渣中のニ
ッケル含有量は５％以上になるので、この残渣をニッケ
ル原料として有効利用することも可能である。Further, according to the present invention, since the nickel content in the vanadium leaching residue is 5% or more, it is also possible to effectively utilize this residue as a nickel raw material.
以上の様に、本発明は、特定条件下で加圧浸出すること
により脱硫廃触媒からモリブデン成分を極めて高収率で
選択抽出することを可能にし、従って抽出液からのモリ
ブデン成分の回収方法も簡素化されて一挙に化学品純度
のモリブデン製品の回収が可能となり、更にモリブデン
成分を選択抽出させるため、残渣からのバナジウム成分
の抽出回収方法も簡素化され、上記廃触媒からのモリブ
デン成分とバナジウム成分の回収に大きく寄与すること
ができる。As described above, the present invention makes it possible to selectively extract molybdenum components from desulfurization waste catalysts at extremely high yields by pressurized leaching under specific conditions, and therefore also provides a method for recovering molybdenum components from extract liquid. This simplifies the recovery of molybdenum products with chemical purity in one fell swoop. Furthermore, in order to selectively extract the molybdenum component, the extraction and recovery method for the vanadium component from the residue has also been simplified. It can greatly contribute to the recovery of components.
以下に実施例を示して本発明をさらに具体的に説明する
。EXAMPLES The present invention will be explained in more detail with reference to Examples below.
実施例 １
下記第１表の組成を有する廃触媒焙焼生成物２５０？を
、２５％アンモニア水５００ｍｌおよび水３５０ｍｌに
硫酸アンモニウム５００Ｉを溶解した水溶液を用いて、
酸素分圧１０ｋｇ／ｃｕｔ，反応温度１２０℃の条件下
で１時間加圧浸出させ第２表の様な浸出率が得られた。Example 1 A waste catalyst roasted product 250? having the composition shown in Table 1 below. using an aqueous solution of ammonium sulfate 500I dissolved in 500ml of 25% ammonia water and 350ml of water,
Pressure leaching was carried out for 1 hour under conditions of an oxygen partial pressure of 10 kg/cut and a reaction temperature of 120° C., and the leaching rates shown in Table 2 were obtained.
実施例 ２
前記第１表の組成を有する廃触媒焙焼生成物２５０Ｎを
、炭酸アンモン１６６Ｓ、硫酸アンモニウム５００ｆを
水８６０ｍｌに溶解した水溶液を用いて、酸素分圧２ｋ
ｇ／ｃｍｔ、反応温度１２０℃の条件下で１時間加圧浸
出させ第３表の様な浸出率が得られた。Example 2 250N of the roasted waste catalyst product having the composition shown in Table 1 above was heated to an oxygen partial pressure of 2k using an aqueous solution in which 166S of ammonium carbonate and 500f of ammonium sulfate were dissolved in 860ml of water.
g/cmt and pressure leaching for 1 hour at a reaction temperature of 120°C, the leaching rates shown in Table 3 were obtained.
比較例 １
前記第１表の組成を有する廃触媒焙焼生成物２５ｏｚを
、炭酸アンモン１６６？を水９２０ｒｌに溶解した水溶
液を用いて、酸素分圧１０ｋｇ／ｃｎ２、反応温度１２
０℃の条件下で１時間加圧浸出させ第４表の様な浸出率
が得られた。Comparative Example 1 25 oz of the roasted waste catalyst product having the composition shown in Table 1 above was mixed with 166 ml of ammonium carbonate. using an aqueous solution of 920 rl of water, oxygen partial pressure 10 kg/cn2, reaction temperature 12
Pressure leaching was performed for 1 hour at 0°C, and the leaching rates shown in Table 4 were obtained.
比較例 ２
第５表の組成を有する廃触媒焙焼生成物２５Ｏｒを、苛
性ソーダ１５ｏｇ／７水溶液１ｔを用いて８０℃で３時
間反応させ第６表の様な浸出率が得られた。Comparative Example 2 25 Or of the roasted waste catalyst product having the composition shown in Table 5 was reacted with 1 t of caustic soda 15 og/7 aqueous solution at 80° C. for 3 hours to obtain the leaching rate shown in Table 6.
Claims (1)
０℃以上で酸化焙焼し、得られた焙焼生成物を、焙焼生
成物中のＭ４量に対して１〜３当量のアンモニア濃度の
アンモニア水または炭酸アンモン水溶液に、焙焼生成物
中のＶ量に対して７当量以上の硫酸アンモニウムを溶解
させてなる水溶液中で、１１０℃以上の温度、ｌｋｇ／
ｃｍ４以上の酸素分圧のもとて３０分以上加圧浸出処理
することによって該焙焼生成物中の金属成分のうちモリ
ブデン成分を選択的に抽出することからなる脱硫廃触媒
からのモリブデンの選択抽出法。1 50% of the desulfurization waste catalyst containing at least Mo and ■
The roasted product obtained by oxidative roasting at 0°C or higher is added to ammonia water or ammonium carbonate aqueous solution with an ammonia concentration of 1 to 3 equivalents based on the amount of M4 in the roasted product. In an aqueous solution prepared by dissolving 7 equivalents or more of ammonium sulfate with respect to the V amount of
Selection of molybdenum from desulfurization waste catalyst, which consists of selectively extracting the molybdenum component among the metal components in the roasted product by performing pressure leaching treatment for 30 minutes or more under an oxygen partial pressure of cm4 or more. Extraction method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP54078798A JPS5814367B2 (en) | 1979-06-22 | 1979-06-22 | Selective extraction method of molybdenum from desulfurization waste catalyst |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP54078798A JPS5814367B2 (en) | 1979-06-22 | 1979-06-22 | Selective extraction method of molybdenum from desulfurization waste catalyst |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS565328A JPS565328A (en) | 1981-01-20 |
| JPS5814367B2 true JPS5814367B2 (en) | 1983-03-18 |
Family
ID=13671874
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP54078798A Expired JPS5814367B2 (en) | 1979-06-22 | 1979-06-22 | Selective extraction method of molybdenum from desulfurization waste catalyst |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5814367B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007032228A1 (en) * | 2005-09-16 | 2007-03-22 | Mitsubishi Rayon Co., Ltd. | Methods for recovery of molybdenum and process for preparation of catalysts |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS498491A (en) * | 1972-05-17 | 1974-01-25 |
-
1979
- 1979-06-22 JP JP54078798A patent/JPS5814367B2/en not_active Expired
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS498491A (en) * | 1972-05-17 | 1974-01-25 |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS565328A (en) | 1981-01-20 |
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