JP2018162479A - Method for recovering high-purity rhenium sulfide - Google Patents

Method for recovering high-purity rhenium sulfide Download PDF

Info

Publication number
JP2018162479A
JP2018162479A JP2017058863A JP2017058863A JP2018162479A JP 2018162479 A JP2018162479 A JP 2018162479A JP 2017058863 A JP2017058863 A JP 2017058863A JP 2017058863 A JP2017058863 A JP 2017058863A JP 2018162479 A JP2018162479 A JP 2018162479A
Authority
JP
Japan
Prior art keywords
rhenium
sulfide
slurry
rhenium sulfide
oxidation
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.)
Granted
Application number
JP2017058863A
Other languages
Japanese (ja)
Other versions
JP6842041B2 (en
Inventor
泰輔 鶴見
Taisuke Tsurumi
泰輔 鶴見
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sumitomo Metal Mining Co Ltd
Original Assignee
Sumitomo Metal Mining Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Sumitomo Metal Mining Co Ltd filed Critical Sumitomo Metal Mining Co Ltd
Priority to JP2017058863A priority Critical patent/JP6842041B2/en
Publication of JP2018162479A publication Critical patent/JP2018162479A/en
Application granted granted Critical
Publication of JP6842041B2 publication Critical patent/JP6842041B2/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02PCLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00Technologies related to metal processing
    • Y02P10/20Recycling

Landscapes

  • Inorganic Compounds Of Heavy Metals (AREA)
  • Manufacture And Refinement Of Metals (AREA)
  • Treating Waste Gases (AREA)

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing rhenium sulfide that can produce a high-purity rhenium sulfide product.SOLUTION: A method for recovering rhenium sulfide includes a leaching step 1 of subjecting an object to be treated which includes rhenium, arsenic and cadmium to oxidation leaching to produce a leachate, a neutralization solution purification step 2 of neutralizing the resultant leachate with an alkali to produce a neutralization precipitate containing arsenic and cadmium and removing the neutralization precipitate from a neutralization filtrate containing rhenium and a rhenium recovery step 3 of subjecting the neutralization filtrate to sulfuration treatment to recover rhenium contained in the neutralization filtrate as rhenium sulfide. In the rhenium recovery step 3, a washing liquid is added to the slurry before recovering rhenium sulfide and the slurry is washed under conditions of an acid concentration of 2.0 normality or less and a pH of 7.0 or less and an oxidation-reduction potential during washing in the range of -0.5 V to 0.2 V (silver/silver chloride electrode as a reference electrode).SELECTED DRAWING: Figure 1

Description

本発明は、非鉄金属製錬工程で回収されるレニウム、カドミウム、ヒ素などを含む硫化物から純度の高い硫化レニウムを回収する方法に関するものである。   The present invention relates to a method for recovering high-purity rhenium sulfide from a sulfide containing rhenium, cadmium, arsenic and the like recovered in a non-ferrous metal smelting process.

レニウムは特殊合金の添加元素や触媒などに利用される希少金属であり、天然には主としてモリブデンの原料となる輝水鉛鉱(Molybdenite、MoS)の中に含まれている。モリブデンの製錬工程では、モリブデンを可溶性化するために輝水鉛鉱の酸化焙焼が行われる。この酸化焙焼の際、輝水鉛鉱に含まれるレニウムは、揮発性酸化物Reとして輝水鉛鉱から分離され、スクラバー等の洗浄工程で回収された後、精製される。 Rhenium is a rare metal used as an additive element and catalyst for special alloys, and is naturally contained in molybdenite (MoS 2 ), which is a raw material of molybdenum. In the smelting process of molybdenum, oxidation roasting of molybdenite is performed to solubilize molybdenum. At the time of this oxidation roasting, rhenium contained in molybdenite is separated from molybdenite as a volatile oxide Re 2 O 7 , recovered in a cleaning process such as a scrubber, and then purified.

また、輝水鉛鉱は例えば黄銅鉱(Chalcopyrite、CuFeS)などの銅鉱物と共存することが知られているが、これら輝水鉛鉱と黄銅鉱とは浮遊選鉱などの一般的な方法では分離するのは困難である。そのため、浮遊選鉱の後段に位置する溶鉱炉などの炉を用いて乾式製錬により黄銅鉱から銅を得る場合は、輝水鉛鉱も同時に炉に装入されてしまう。その結果、炉から排出される主に亜硫酸ガスからなる排ガスには揮発したレニウムが混入する。 In addition, it is known that pyroxenite coexists with copper minerals such as chalcopyrite (CuFeS 2 ), but these hydropyrite and chalcopyrite are separated by a general method such as flotation. It is difficult. For this reason, when copper is obtained from chalcopyrite by dry smelting using a furnace such as a blast furnace located at the subsequent stage of flotation, pyroxenite is also charged into the furnace at the same time. As a result, volatilized rhenium is mixed in the exhaust gas mainly composed of sulfurous acid gas discharged from the furnace.

硫酸製造プラントに原料ガスとして送られるこの排ガスには、上記レニウムのほか、銅鉱石に含まれるヒ素やカドミウム、亜鉛などが固体状または液体状の微粒子(フュームとも称される)の形で浮遊している。これら不純物を除去するため、排ガスは硫酸製造工程の前処理としてスクラバー等による洗浄処理が施される。排ガスに含まれるレニウムもこの洗浄処理で分離されるため、上記した多くの種類の元素からレニウムだけを選択的に回収することが必要となる。   In addition to rhenium, arsenic, cadmium, and zinc contained in copper ore float in the form of solid or liquid fine particles (also called fumes) in the exhaust gas sent to the sulfuric acid production plant as raw material gas. ing. In order to remove these impurities, the exhaust gas is subjected to a cleaning process using a scrubber or the like as a pretreatment in the sulfuric acid production process. Since rhenium contained in the exhaust gas is also separated by this cleaning process, it is necessary to selectively recover only rhenium from the above-described many types of elements.

レニウムを選択的に回収する方法の一つとして、特許文献1には亜硫酸ガスを含んだ排ガスを硫化処理して得られるレニウムとヒ素とを少なくとも含む硫化物に対して酸化浸出を行い、得られた浸出液をアルカリで中和することで不純物であるヒ素を安定な形態で分離除去してヒ素品位の低い硫化レニウムを得る方法が開示されている。   As one method for selectively recovering rhenium, Patent Document 1 discloses a method obtained by performing oxidative leaching on a sulfide containing at least rhenium and arsenic obtained by sulfidizing exhaust gas containing sulfurous acid gas. A method of obtaining rhenium sulfide having a low arsenic quality by separating and removing arsenic, which is an impurity, in a stable form by neutralizing the leachate with an alkali is disclosed.

具体的には、非鉄金属製錬工場の熔錬工程から排出される亜硫酸ガスを含んだ排ガスを洗浄工程において水洗し、この洗浄工程から排出される、レニウム、ヒ素、カドミウムなどの様々な不純物元素を含んだ洗浄排液を硫化処理してこれら不純物元素を硫化澱物として回収する。そして、この硫化澱物に対して下記に示す浸出工程、中和浄液工程、及びレニウム回収工程で処理を行ってレニウムを硫化レニウムとして回収するものである。   Specifically, exhaust gas containing sulfurous acid gas discharged from the smelting process of a non-ferrous metal smelting plant is washed with water in the cleaning process, and various impurity elements such as rhenium, arsenic, cadmium, etc. discharged from this cleaning process. The effluent containing sulphite is sulfurized to recover these impurity elements as sulfided starch. And it processes by this leaching process, the neutralization liquid purification process, and rhenium collection | recovery process which are shown below to collect | recover rhenium as rhenium sulfide.

(浸出工程)
浸出工程では、硫化澱物に対して硫酸を主成分とする液体を加えてレパルプする。レパルプにより得たスラリーに高温の空気を吹き込んで酸化浸出を行う。これによりレニウムとその他の様々な元素の一部を含んだpHがおよそ0の浸出液が得られる。同時に、この酸化浸出では浸出されなかった元素が濃縮された浸出残渣が得られる。浸出残渣は、澱物処理工程に送られ、そこで残渣と廃液とに分けられる。分けた残渣は熔錬工程に繰り返され、廃液は排水処理工程で処理される。
(Leaching process)
In the leaching step, repulping is performed by adding a liquid containing sulfuric acid as a main component to the sulfide starch. Oxidation leaching is performed by blowing high-temperature air into the slurry obtained by repulping. Thus, a leachate having a pH of about 0 containing rhenium and some other various elements is obtained. At the same time, a leaching residue enriched with elements not leached by this oxidative leaching is obtained. The leach residue is sent to the starch treatment process where it is divided into residue and waste liquor. The divided residue is repeated in the smelting process, and the waste liquid is processed in the wastewater treatment process.

(中和浄液工程)
中和浄液工程では、上記浸出液に中和剤として例えば苛性ソーダを添加し、およそpH7で中和処理する。これを濾過することにより、レニウムが濃縮された中和濾液と、レニウム以外の元素を含む中和澱物が得られる。この中和澱物は熔錬工程に繰り返される。
(Neutralization and purification process)
In the neutralization liquid purification step, for example, caustic soda is added to the leachate as a neutralizing agent, and neutralized at about pH 7. By filtering this, a neutralized filtrate in which rhenium is concentrated and a neutralized starch containing elements other than rhenium are obtained. This neutralized starch is repeated in the smelting process.

(レニウム回収工程)
レニウム回収工程では、上記中和濾液に硫酸を添加してpHをほぼ0に調整すると共に、水硫化ナトリウムを添加する。これら中和濾液の液張り、pH調整、及び水硫化ソーダ添加からなる硫化処理と称する一連の操作により中和濾液中のレニウムが硫化レニウムとして析出する。この硫化レニウムを含むスラリーを固液分離して硫化レニウムが回収される。スラリーから硫化レニウムが除かれた後の溶液は廃液として排水処理工程で処理される。
(Rhenium recovery process)
In the rhenium recovery step, sulfuric acid is added to the neutralized filtrate to adjust the pH to almost zero, and sodium hydrosulfide is added. The rhenium in the neutralized filtrate is precipitated as rhenium sulfide by a series of operations called sulfiding treatment consisting of filling the neutralized filtrate, adjusting the pH, and adding sodium hydrosulfide. The slurry containing rhenium sulfide is separated into solid and liquid to recover rhenium sulfide. The solution after rhenium sulfide is removed from the slurry is treated as a waste liquid in a waste water treatment step.

また、特許文献2には、上記と同様の浸出工程、中和洗浄工程、及びレニウム回収工程からなる方法によりヒ素品位の低い硫化レニウムを製造する方法において、該硫化レニウム中のカドミウム品位も同時に低く抑える方法が開示されている。具体的には、この方法は上記中和浄液工程において、苛性ソーダ添加後にカルシウム系中和剤を添加し、より高いpHで中和するものである。   Patent Document 2 discloses a method for producing rhenium sulfide having a low arsenic quality by a method comprising a leaching process, a neutralization washing process, and a rhenium recovery process similar to the above, and the cadmium quality in the rhenium sulfide is also low. A method of suppressing is disclosed. Specifically, this method is to neutralize at a higher pH by adding a calcium-based neutralizing agent after the addition of caustic soda in the neutralizing and cleaning step.

国際公開第2013/129130号International Publication No. 2013/129130 特開2015−212401号公報JP-A-2015-212401

上記文献1及び2の方法によりヒ素品位の低い硫化レニウムを回収することができるものの、いずれの方法においても、中和浄液工程において硫酸を含む浸出液を苛性ソーダで中和する際、硫酸ナトリウムが多量に生成して後工程のレニウム回収工程において硫化レニウムに混入し、そのまま硫化レニウム製品中に残存するので問題になることがあった。そこで、硫化レニウム中の硫酸ナトリウムの含有率を20質量%以下に抑えることが求められていた。   Although rhenium sulfide having a low arsenic quality can be recovered by the methods of the above-mentioned documents 1 and 2, in any of the methods, when neutralizing the leachate containing sulfuric acid with caustic soda in the neutralization liquid cleaning step, a large amount of sodium sulfate is present. In the subsequent rhenium recovery process, it is mixed with rhenium sulfide and remains in the rhenium sulfide product as it is. Therefore, it has been required to suppress the content of sodium sulfate in rhenium sulfide to 20% by mass or less.

硫酸ナトリウム含有率を上記の通り低く抑える方法として、レニウム回収工程における硫酸および水硫化ソーダの添加量を規定量より低くすることが考えられる。この方法は、硫化レニウムへの硫酸ナトリウムの混入をある程度抑えることができるものの、レニウムの回収率が低下する問題を生ずることがあった。また、他の方法としてレニウム回収工程で得た硫化レニウムを水で洗浄することが考えられる。この方法により硫化レニウム中の硫酸ナトリウムの含有率を上記の規定値より低くすることができるが、レニウムが洗浄液に溶解してレニウムの回収率が低下する問題を生ずることがあった。   As a method of keeping the sodium sulfate content low as described above, it is conceivable that the addition amount of sulfuric acid and sodium hydrosulfide in the rhenium recovery step is made lower than the specified amount. Although this method can suppress the mixing of sodium sulfate into rhenium sulfide to some extent, it sometimes causes a problem that the recovery rate of rhenium decreases. Another possible method is to wash the rhenium sulfide obtained in the rhenium recovery step with water. By this method, the content of sodium sulfate in rhenium sulfide can be made lower than the above specified value, but there is a problem that rhenium is dissolved in the cleaning liquid and the recovery rate of rhenium is lowered.

本発明は、上記した従来の硫化レニウムの製造方法が抱える問題点に鑑みてなされたものであり、硫化澱物などのレニウムを含む物質に対して浸出工程、中和洗浄工程、及びレニウム回収工程からなる一連の工程で処理して硫化レニウムを作製する硫化レニウムの製造方法において、該レニウム回収工程の硫化処理によって得た硫化レニウムを含むスラリーから硫酸ナトリウムを選択的に取り除いて高純度の硫化レニウム製品を作製することが可能な硫化レニウムの製造方法を提供することを目的とする。   The present invention has been made in view of the problems of the above-described conventional method for producing rhenium sulfide, and is a leaching process, a neutralization cleaning process, and a rhenium recovery process for a rhenium-containing substance such as a sulfide starch. In the method for producing rhenium sulfide, the rhenium sulfide is selectively removed by removing sodium sulfate from the slurry containing rhenium sulfide obtained by the sulfurization treatment in the rhenium recovery step. An object of the present invention is to provide a method for producing rhenium sulfide capable of producing a product.

上記目的を達成するため、本発明の硫化レニウム回収方法は、レニウム、ヒ素及びカドミウムを含む処理対象物を酸化浸出して浸出液を得る浸出工程と、前記浸出液をアルカリで中和してヒ素及びカドミウムを含有する中和沈殿物を生成し、レニウムを含有する中和濾液から該中和沈殿物を除去する中和浄液工程と、前記中和濾液を硫化処理して該中和濾液に含まれるレニウムを硫化レニウムとして回収するレニウム回収工程とを含む硫化レニウムの回収方法であって、前記レニウム回収工程において、前記硫化レニウムを回収する前にそのスラリーに洗浄液を加えて、2.0規定以下で且つpH7.0以下の酸濃度および酸化還元電位(銀−塩化銀参照電極)が−0.5V以上0.2V以下の条件下で洗浄することを特徴とする硫化レニウムの回収方法。   In order to achieve the above object, the rhenium sulfide recovery method of the present invention includes a leaching step for obtaining a leachate by oxidizing and leaching a treatment object containing rhenium, arsenic and cadmium, and neutralizing the leachate with an alkali to arsenic and cadmium. A neutralization purification step for producing a neutralized precipitate containing phosphine and removing the neutralized precipitate from the rhenium-containing neutralized filtrate, and the neutralized filtrate is subjected to sulfidation treatment and contained in the neutralized filtrate. A rhenium sulfide recovery method including a rhenium recovery step of recovering rhenium as rhenium sulfide, wherein in the rhenium recovery step, a cleaning liquid is added to the slurry before the rhenium sulfide is recovered, and the rhenium recovery step is performed at a rate of 2.0 or less. In addition, the rhenium sulfide solution is characterized by washing under conditions where the acid concentration at pH 7.0 or lower and the oxidation-reduction potential (silver-silver chloride reference electrode) are −0.5 V or higher and 0.2 V or lower. Collection method.

本発明によれば、レニウムの回収率をほとんど低下させることなく硫化レニウム製品中の硫酸ナトリウム等の不純物の濃度を低減することができる。   According to the present invention, it is possible to reduce the concentration of impurities such as sodium sulfate in a rhenium sulfide product without substantially reducing the recovery rate of rhenium.

本発明の一具体例のレニウム回収方法の工程フロー図である。It is a process flowchart of the rhenium collection | recovery method of one specific example of this invention. 図1の工程フローのうちレニウム回収工程を詳細に示した工程フロー図である。It is the process flow figure which showed the rhenium collection | recovery process in detail among the process flows of FIG.

以下、本発明の硫化レニウムの回収方法の一具体例について説明する。この本発明の一具体例の硫化レニウムの回収方法は、非鉄金属製錬工場の熔練炉からの排ガスを水洗した時に排出される洗浄排水に対して、硫化処理を施すことによって生じる硫化澱物などのレニウム、ヒ素及びカドミウムを含む物質を処理対象物としており、この処理対象物を酸化浸出して浸出液を得る浸出工程と、得られた浸出液をアルカリで中和してヒ素及びカドミウムを含有する中和沈殿物を生成し、レニウムを含有する中和濾液からこの中和沈殿物を除去する中和浄液工程と、得られた中和濾液を硫化処理して該中和濾液に含まれるレニウムを硫化レニウムとして回収するレニウム回収工程とからなる。以下、これら工程の各々について、図1の工程フロー図を参照しながら具体的に説明する。   Hereinafter, a specific example of the method for recovering rhenium sulfide of the present invention will be described. The method for recovering rhenium sulfide according to one embodiment of the present invention is a sulfurized starch produced by subjecting cleaning wastewater discharged when washing exhaust gas from a melting furnace of a non-ferrous metal smelting plant to sulfidation. A substance containing rhenium, arsenic and cadmium such as leaching step is obtained by oxidative leaching to obtain a leachate, and the obtained leachate is neutralized with alkali to contain arsenic and cadmium. A neutralization purification step for producing a neutralized precipitate and removing the neutralized precipitate from the neutralized filtrate containing rhenium, and a rhenium contained in the neutralized filtrate by sulfiding the resulting neutralized filtrate And a rhenium recovery step of recovering as rhenium sulfide. Hereinafter, each of these processes will be described in detail with reference to the process flow chart of FIG.

(浸出工程)
浸出工程1では、回収対象元素のレニウムのほか、カドミウムやヒ素などの不純物を含む上記の硫化澱物などの処理対象物に対して硫酸を主成分とする水溶液を加えてレパルプする。このレパルプにより生成されるスラリーに高温の空気又は空気及び水蒸気を吹き込んで酸化浸出を行う。酸化浸出後は必要に応じて固液分離を行うことで、上記処理対象物に含まれるほとんどのレニウム及びその他の様々な元素の一部を含んだpHがおよそ0の浸出液と、上記酸化浸出1では浸出されなかった元素が濃縮された浸出残渣とが得られる。浸出液は後述する中和洗浄工程2に送られ、浸出残渣は澱物処理工程4に送られる。この澱物処理工程4では遠心分離などにより固液分離が行われ、残渣と廃液とに分けられる。残渣は熔錬工程5に繰り返され、廃液は排水処理工程6で処理される。
(Leaching process)
In the leaching process 1, repulping is performed by adding an aqueous solution containing sulfuric acid as a main component to the processing target such as the above-mentioned sulfided starch containing impurities such as cadmium and arsenic in addition to rhenium as an element to be recovered. High temperature air or air and water vapor are blown into the slurry produced by the repulping to perform oxidative leaching. After the oxidative leaching, solid-liquid separation is performed as necessary, so that the leaching solution having a pH of approximately 0 containing a part of most of rhenium and other various elements contained in the object to be treated, and the oxidative leaching 1 In this case, a leaching residue enriched with elements not leached is obtained. The leachate is sent to the neutralization washing step 2 described later, and the leach residue is sent to the starch treatment step 4. In the starch processing step 4, solid-liquid separation is performed by centrifugation or the like, and the residue is separated into a residue and a waste liquid. The residue is repeated in the smelting step 5 and the waste liquid is treated in the waste water treatment step 6.

(中和浄液工程)
中和浄液工程2では、上記の浸出液に中和剤として例えば苛性ソーダを添加し、およそpH7で中和処理する。この中和処理後はフィルタープレスなどの固液分離を行うことでレニウムが濃縮された中和濾液と、レニウム以外の元素からなる中和澱物とが得られる。この中和澱物は回収された後、上記の澱物処理工程4の残渣の場合と同様に熔錬工程5に繰り返される。
(Neutralization and purification process)
In the neutralization liquid purification process 2, for example, caustic soda is added to the above leachate as a neutralizing agent and neutralized at about pH 7. After this neutralization treatment, a solid-liquid separation such as a filter press is performed to obtain a neutralized filtrate in which rhenium is concentrated and a neutralized starch composed of elements other than rhenium. After this neutralized starch is recovered, it is repeated in the smelting step 5 in the same manner as the residue in the starch processing step 4 described above.

(レニウム回収工程)
レニウム回収工程3では、上記中和洗浄工程2で得た中和濾液を硫化処理して該中和濾液に含まれるレニウムが硫化レニウムとして回収される。このレニウム回収工程3について図2を参照しながらより詳細に説明する。図2に示すように、レニウム回収工程3は硫化工程31、スラリー洗浄工程32、及び固液分離工程33の一連の工程からなる。
(Rhenium recovery process)
In the rhenium recovery step 3, the neutralized filtrate obtained in the neutralization washing step 2 is subjected to sulfurization treatment, and rhenium contained in the neutralized filtrate is recovered as rhenium sulfide. The rhenium recovery step 3 will be described in more detail with reference to FIG. As shown in FIG. 2, the rhenium recovery process 3 includes a series of processes including a sulfurization process 31, a slurry washing process 32, and a solid-liquid separation process 33.

先ず硫化工程で31では、上記の中和濾液に酸および硫化剤を添加して該中和濾液に含まれるレニウムを硫化レニウムとして沈殿させる。酸の添加では、反応液のpHが約0程度になるように添加量を調整する。添加する酸には硫酸または塩酸を用いることができるが、反応槽等の設備機器に用いる材質の選択の自由度や揮発性などの観点から硫酸の使用が望ましい。   First, at 31 in the sulfiding step, an acid and a sulfiding agent are added to the neutralized filtrate to precipitate rhenium contained in the neutralized filtrate as rhenium sulfide. In the addition of acid, the addition amount is adjusted so that the pH of the reaction solution is about 0. Although sulfuric acid or hydrochloric acid can be used as the acid to be added, it is desirable to use sulfuric acid from the viewpoint of freedom of selection of materials used for equipment such as a reaction tank and volatility.

一方、硫化剤としては、水硫化ナトリウムなどの水硫化アルカリ、硫化ナトリウムなどの硫化アルカリ、硫化カルシウムなどの硫化アルカリ土類、硫化水素等を用いることができるが、これらの中では水硫化ナトリウムや硫化水素が入手しやすいので好適であり、取り扱いやすさの点で水硫化ナトリウムがより好適である。この反応により生成した硫化レニウムを含む懸濁液は、好ましくは静置(デカンテーション)により上澄み液を除くことで、沈降した硫化レニウムを含むスラリー(以、下硫化レニウムスラリー又は単にスラリーと称する)が得られる。   On the other hand, as the sulfiding agent, alkali hydrosulfide such as sodium hydrosulfide, alkali sulfide such as sodium sulfide, alkaline sulfide earth such as calcium sulfide, hydrogen sulfide, etc. can be used. Hydrogen sulfide is preferable because it is easily available, and sodium hydrosulfide is more preferable in terms of ease of handling. The suspension containing rhenium sulfide generated by this reaction is preferably a slurry containing precipitated rhenium sulfide by removing the supernatant liquid by decantation (hereinafter referred to as lower rhenium sulfide slurry or simply slurry). Is obtained.

次のスラリー洗浄工程32では、上記スラリーに対して、体積基準で5倍以上の洗浄液を添加混合して洗浄する。その際、酸濃度が2.0規定以下で且つpH7.0以下であって、酸化還元電位(銀−塩化銀電極を参照電極としたときの測定値であり、以降の酸化還元電位においても同じである)が−0.5V以上0.2V以下の条件下で硫化レニウムを洗浄する。この酸濃度が2.0規定を超えると、硫化レニウムが再溶解する。また酸性の硫化レニウムスラリーに洗浄液として水を添加して洗浄を繰り返しても、pHは7を超えることがないので、pH7を上限にしている。酸化還元電位が0.2Vを超えると、硫化レニウムは過レニウム酸イオンとなり再溶解する。強い還元剤を添加すれば、酸化還元電位を低くすることができるが、経済的でないため、酸化還元電位の下限は−0.5Vで十分である。なお、上記の酸濃度の上限については、2.0規定に代えて当該2.0規定のときのpH値で限定してもよい。このpH値は一般的にはpH=−log[酸濃度]から導きだすことができ、上記の場合ではpH−0.3程度になるが、pHが0未満になるとpH計での測定が困難になるので酸濃度の上限は規定で限定するのが好ましい。   In the next slurry washing step 32, the above slurry is washed by adding and mixing a cleaning solution of 5 times or more on a volume basis. At that time, the acid concentration is 2.0 N or less and the pH is 7.0 or less, and the oxidation-reduction potential (measured value when a silver-silver chloride electrode is used as a reference electrode, the same applies to the subsequent oxidation-reduction potentials. The rhenium sulfide is washed under the condition of −0.5V or more and 0.2V or less. When this acid concentration exceeds 2.0 N, rhenium sulfide is redissolved. Further, even when water is added to the acidic rhenium sulfide slurry as a cleaning solution and the cleaning is repeated, the pH does not exceed 7, so the pH is set to the upper limit. When the oxidation-reduction potential exceeds 0.2 V, rhenium sulfide becomes perrhenate ions and redissolves. If a strong reducing agent is added, the oxidation-reduction potential can be lowered. However, since it is not economical, −0.5 V is sufficient as the lower limit of the oxidation-reduction potential. In addition, about the upper limit of said acid concentration, it may replace with 2.0 specification and may be limited by the pH value at the time of the said 2.0 specification. This pH value can be generally derived from pH = -log [acid concentration]. In the above case, it becomes about pH-0.3, but when the pH is less than 0, it is difficult to measure with a pH meter. Therefore, it is preferable to limit the upper limit of the acid concentration by regulation.

上記の洗浄では、洗浄液の量がスラリーの量に対して体積基準で5倍未満では、洗浄中の洗浄液に含まれる硫酸ナトリウム濃度が高くなりすぎて洗浄不足のリスクが高くなるうえ、硫酸ナトリウムが硫化レニウムの付着液に伴って後工程の濾過器へキャリーオーバーする量が増加するおそれがある。洗浄液の量の上限については特に制約はないが、15倍程度を超えるとそれ以上効果が上昇しなくなるので不経済である。なお、洗浄不足を防ぐため、30分以上撹拌することが好ましい。   In the above cleaning, if the amount of the cleaning solution is less than 5 times the volume of the slurry, the concentration of sodium sulfate contained in the cleaning solution being cleaned becomes too high, and the risk of insufficient cleaning is increased. There is a possibility that the amount carried over to the filter in the subsequent process increases with the rhenium sulfide adhesion liquid. The upper limit of the amount of the cleaning liquid is not particularly limited, but if it exceeds about 15 times, the effect is not increased any more, which is uneconomical. In order to prevent insufficient washing, it is preferable to stir for 30 minutes or more.

上記の洗浄中の酸濃度は、硫酸または塩酸を用いることで上記範囲内に調整することができるが、反応槽等の設備器機に用いる材質の選択の自由度や揮発性などの観点から硫酸を用いるのが望ましい。一方、酸化還元電位は、アルカリ金属またはアルカリ土類金属の硫化物、硫化水素、水素等の還元剤などを用いて調整することができる。これらの中では、入手しやすく且つ硫化レニウムがレニウムイオンと硫黄イオンに分解することを抑制できるので、水硫化ナトリウム又は硫化水素を用いるのが望ましく、取り扱いやすさの点で水硫化ナトリウムがより望ましい。   The acid concentration during the washing can be adjusted within the above range by using sulfuric acid or hydrochloric acid, but sulfuric acid is used from the viewpoint of freedom of choice of materials used for equipment such as reaction vessels and volatility. It is desirable to use it. On the other hand, the redox potential can be adjusted using a reducing agent such as an alkali metal or alkaline earth metal sulfide, hydrogen sulfide, or hydrogen. Among these, since it is easily available and rhenium sulfide can be prevented from being decomposed into rhenium ions and sulfur ions, it is preferable to use sodium hydrosulfide or hydrogen sulfide, and sodium hydrosulfide is more preferable in terms of ease of handling. .

上記のスラリーの洗浄後は、固液分離のため上記の洗浄液を含むスラリーを2時間以上静置する。この静置時間が2時間よりも短いと固液分離が不十分となり、スラリーに含まれる硫化レニウムが上澄み液側に排出されてロスになる可能性が高まる。このロスを減らすため、後述する上澄み液の抜出量を減らすことが考えられるが、この場合は上澄み液の抜出し後に残存するスラリーの濃度が低くなり、後工程の固液分離工程33において濾過時間が長くなるので生産効率が低下する。   After washing the slurry, the slurry containing the washing solution is allowed to stand for 2 hours or more for solid-liquid separation. If this standing time is shorter than 2 hours, solid-liquid separation is insufficient, and the possibility that rhenium sulfide contained in the slurry is discharged to the supernatant liquid side and becomes lost increases. In order to reduce this loss, it is conceivable to reduce the amount of the supernatant liquid to be described later. In this case, the concentration of the slurry remaining after the supernatant liquid is extracted becomes low, and the filtration time is reduced in the solid-liquid separation step 33 in the subsequent step. The production efficiency is lowered because the length becomes longer.

このスラリー洗浄工程32の静置においても上記の洗浄中の場合と同様に、スラリーの酸濃度を2.0規定以下で且つpHを7.0以下とし、酸化還元電位を−0.5V以上0.2V以下となるようにするのが好ましい。なお、上記の洗浄中や静置している間は、スラリーの酸化還元電位が0.2Vを超えないようにするのが好ましい。酸化還元電位の具体的な調整方法としては、洗浄中や静置している間の洗浄槽や静置槽内の酸化還元電位を測定し、酸化還元電位が0.2Vを超えそうになったら還元剤を添加する。あるいは、酸化還元電位が0.2Vを超えないように、あらかじめ還元剤を多めに洗浄水に添加しておく。また、槽内は窒素パージし、空気中の酸素が洗浄液を含むスラリーにできるだけ混入しないようにする。   Also in the standing of the slurry washing step 32, as in the case of the washing described above, the acid concentration of the slurry is 2.0 N or less, the pH is 7.0 or less, and the oxidation-reduction potential is −0.5 V or more and 0. It is preferable that the voltage be 0.2 V or less. In addition, it is preferable that the oxidation-reduction potential of the slurry does not exceed 0.2 V during the above-described cleaning or standing. As a specific method for adjusting the oxidation-reduction potential, the oxidation-reduction potential in the washing tank or the stationary tank during washing or standing is measured, and the oxidation-reduction potential is about to exceed 0.2V. Add reducing agent. Alternatively, a large amount of reducing agent is previously added to the washing water so that the redox potential does not exceed 0.2V. Further, the inside of the tank is purged with nitrogen so that oxygen in the air is not mixed into the slurry containing the cleaning liquid as much as possible.

静置後は上記洗浄液を含むスラリーの体積の80%以上を上澄み液として抜き出す。上澄み液の抜き出しにより残存する硫化レニウム濃度の高い濃縮スラリーは、次に固液分離工程33においてフィルタープレス等の濾過器に通液して濾過が行われる。この濃縮スラリーの濾過後は、濾過器に通液した濃縮スラリーの量と同体積以上の洗浄液を濾過器に通液するのが好ましい。これにより濾過ケーキが洗浄されるので、硫化レニウムに含まれる硫酸ナトリウム等の不純物の濃度をより一層低減することができる。洗浄後は濾過器内から濾過ケーキを回収し、必要に応じて乾燥することで硫化レニウム製品となる。   After standing, 80% or more of the volume of the slurry containing the cleaning liquid is extracted as a supernatant liquid. The concentrated slurry having a high rhenium sulfide concentration remaining after the removal of the supernatant liquid is then passed through a filter such as a filter press in the solid-liquid separation step 33 for filtration. After filtration of the concentrated slurry, it is preferable to pass a cleaning liquid having the same volume or more as the amount of the concentrated slurry passed through the filter through the filter. Thereby, since the filter cake is washed, the concentration of impurities such as sodium sulfate contained in rhenium sulfide can be further reduced. After washing, the filter cake is recovered from the inside of the filter and dried as necessary to obtain a rhenium sulfide product.

硫化レニウム製品の純度をより一層高めるため、上記の固液分離工程33で得た濾過ケーキを再度スラリー洗浄工程32に戻して上記の洗浄とその後の固液分離とを繰り返してもよい。この場合は、洗浄中および静置している間のスラリーの酸濃度および酸化還元電位を上記した範囲内に維持することで、レニウムの再溶解による損失を抑えることができる。以上説明した硫化レニウムの回収方法により、非鉄金属製錬工場の熔錬炉から排出される排ガスに随伴するレニウムの硫化物等のレニウムを含む物質から高純度の硫化レニウムを効率よく回収ことができる。   In order to further increase the purity of the rhenium sulfide product, the filter cake obtained in the solid-liquid separation step 33 may be returned to the slurry washing step 32 to repeat the washing and the subsequent solid-liquid separation. In this case, the loss due to re-dissolution of rhenium can be suppressed by maintaining the acid concentration and oxidation-reduction potential of the slurry within the above range during washing and standing. By the rhenium sulfide recovery method described above, high-purity rhenium sulfide can be efficiently recovered from rhenium-containing substances such as rhenium sulfide accompanying exhaust gas discharged from a smelting furnace of a non-ferrous metal smelting plant. .

[実施例1]
銅製錬工場で発生した亜硫酸ガスを含む排ガスを水洗する洗浄塔からの洗浄排液に対して水硫化ソーダを用いて硫化処理し、レニウムを含む硫化澱物を回収した。この硫化澱物に対して、図1の工程フローに沿って処理し、硫化レニウムを回収した。具体的には、先ず硫化澱物に濃度150g/Lの硫酸水溶液を加えてレパルプし、得られたスラリーの温度が70℃になるように空気と共に蒸気を吹き込み、酸化浸出を行った。これによりpHがおよそ0の浸出液を得た(浸出工程1)。この浸出液を25℃でpHが6.8になるように、20質量%の苛性ソーダを添加して中和処理をして中和澱物を生成させた。この中和澱物を濾紙を敷いたヌッチェを用いて除去し、中和濾液を得た(中和浄液工程2)。
[Example 1]
The exhaust gas containing sulfurous acid gas generated at a copper smelting plant was subjected to sulfidation treatment using sodium hydrosulfide with respect to the washing effluent from the washing tower for washing with water, and the sulfurized starch containing rhenium was recovered. The sulfided starch was treated along the process flow of FIG. 1 to recover rhenium sulfide. Specifically, first, a sulfuric acid aqueous solution having a concentration of 150 g / L was added to the sulfide starch and repulped, and steam was blown in with the air so that the temperature of the resulting slurry was 70 ° C. to perform oxidative leaching. As a result, a leachate having a pH of about 0 was obtained (leaching step 1). The leachate was neutralized by adding 20% by weight of caustic soda to a pH of 6.8 at 25 ° C. to produce a neutralized starch. The neutralized starch was removed using a Nutsche with filter paper, and a neutralized filtrate was obtained (neutralization and purification step 2).

上記の中和濾液に対して、図2に示す工程フローに沿ってレニウム回収工程を行った。具体的には、先ず酸濃度が1.0規定となるように70%硫酸を添加した。この時、反応液のpHはおよそ0であった。次に中和濾液に含まれるレニウムから硫化レニウムを生成するのに必要な化学量論量の1.05倍の水硫化ナトリウムを添加して硫化処理を行い、硫化レニウムを生成し、そのまま2時間静置した(硫化工程31)。   The rhenium recovery process was performed on the neutralized filtrate according to the process flow shown in FIG. Specifically, 70% sulfuric acid was first added so that the acid concentration became 1.0N. At this time, the pH of the reaction solution was approximately zero. Next, 1.05 times the stoichiometric amount of sodium hydrosulfide required to produce rhenium sulfide from rhenium contained in the neutralized filtrate is added to carry out sulfurization treatment to produce rhenium sulfide, which is continued for 2 hours. It was allowed to stand (sulfurization step 31).

上記の2時間の経過後、全体の85体積%に相当する量を上澄み液として上部から抜き取った。残部の硫化レニウムを含むスラリーに対して、体積で10倍量の洗浄水を添加し、40分攪拌した(スラリー洗浄工程32)。この洗浄水には70%硫酸と水硫化ナトリウムを用いて酸濃度1.0規定、銀−塩化銀電極を参照電極とした酸化還元電位0.14Vに調整したものを用いた。撹拌後はそのまま3時間静置した。静置中は容器内を窒素パージし、空気による酸化が生じないようにした。   After the elapse of 2 hours, an amount corresponding to 85% by volume of the whole was extracted from the upper portion as a supernatant. To the slurry containing the remaining rhenium sulfide, 10 times the volume of washing water was added and stirred for 40 minutes (slurry washing step 32). This washing water was prepared by using 70% sulfuric acid and sodium hydrosulfide to adjust the acid concentration to 1.0 N and a redox potential of 0.14 V using a silver-silver chloride electrode as a reference electrode. After stirring, the mixture was allowed to stand for 3 hours. During the standing, the inside of the container was purged with nitrogen to prevent oxidation by air.

尚、上記の撹拌中及び静置を行っている間は、スラリーの酸化還元電位を測定し、酸化還元電位(銀−塩化銀参照電極)が0.15Vを超えたら水硫化ナトリウム溶液を添加する用意をしたが、0.15Vを超えることはなかった。すなわち、上記の撹拌中および静置している間のスラリーの酸濃度は1.0規定(pHは0)、酸化還元電位は0.14Vであった。   During the stirring and standing, the oxidation-reduction potential of the slurry is measured. When the oxidation-reduction potential (silver-silver chloride reference electrode) exceeds 0.15 V, a sodium hydrosulfide solution is added. Although prepared, it did not exceed 0.15V. That is, the acid concentration of the slurry during the stirring and standing was 1.0 N (pH is 0), and the oxidation-reduction potential was 0.14V.

上記3時間の静置後、全体の85%に相当する量を上澄み液として上部から抜き取り、残部の硫化レニウムがより濃縮した濃縮スラリーを濾過器に通液して濾過した(固液分離工程33)。この濃縮スラリーの濾過により得られた濾過ケーキを洗浄するため、上記の酸濃度及び酸化還元電位が調整された洗浄水を、濾過器に通液した上記濃縮スラリーと同体積だけ濾過器に通液した。この濾過ケーキを乾燥機で乾燥することにより実施例1の硫化レニウム製品を作製した。   After standing for 3 hours, an amount corresponding to 85% of the total was taken out from the top as a supernatant, and the concentrated slurry in which the remaining rhenium sulfide was more concentrated was passed through a filter and filtered (solid-liquid separation step 33). ). In order to wash the filter cake obtained by filtration of the concentrated slurry, the washing water adjusted for the acid concentration and oxidation-reduction potential was passed through the filter by the same volume as the concentrated slurry passed through the filter. did. The filter cake was dried with a drier to produce the rhenium sulfide product of Example 1.

[実施例2]
弱塩基性で且つ酸化還元電位の高い洗浄水を用いて硫化レニウムを含むスラリーを洗浄して実施例2の硫化レニウム製品を作製した。具体的には、中和濾液に対して硫酸添加時の酸濃度が1.0規定に代えて2.5規定になるようにすること、水硫化ナトリウムの添加量を化学量論量の1.05倍に代えて1.1倍量にすること、硫化レニウムを含むスラリー及び濃縮スラリーを得るための上澄み液の抜き出し量を各々85%に代えて80%にすること、洗浄水としてpH7.5、酸化還元電位0.4Vのイオン交換水を用い、これをスラリーに対して体積基準で5倍添加したことを除いて上記試料1の場合と同様にして試料2の硫化レニウム製品を作製した。尚、攪拌および静置している間のスラリーの酸濃度は0.5規定(pHは0.3)、酸化還元電位は0.11Vであった。
[Example 2]
A slurry containing rhenium sulfide was washed with wash water having a weak basicity and a high oxidation-reduction potential to produce a rhenium sulfide product of Example 2. Specifically, the neutralized filtrate is adjusted so that the acid concentration at the time of sulfuric acid addition is 2.5 N instead of 1.0 N, and the amount of sodium hydrosulfide added is the stoichiometric amount of 1. Instead of 05 times, the amount is 1.1 times, the amount of supernatant extracted to obtain a slurry containing rhenium sulfide and a concentrated slurry is changed to 80% instead of 85%, and pH 7.5 as washing water. A rhenium sulfide product of Sample 2 was prepared in the same manner as Sample 1 except that ion-exchanged water having an oxidation-reduction potential of 0.4 V was used and this was added 5 times to the slurry on a volume basis. The acid concentration of the slurry during stirring and standing was 0.5 N (pH is 0.3), and the oxidation-reduction potential was 0.11V.

[実施例3]
実施例1の方法により得られた硫化レニウム製品を原料として、スラリー洗浄工程32のスラリー洗浄を再度行った。スラリー洗浄条件は、実施例2の条件を適用した。攪拌中および静置している間の酸濃度はおよそpH3であった。酸化還元電位は−0.07Vを超えた段階で水硫化ナトリウムを添加して、酸化還元電位を−0.07V以下とした。静置中の酸化還元電位は、−0.07V未満であった。静置後、濾過器でスラリーを濾過し、さらに希硫酸で酸濃度pH3、水硫化ナトリウムで酸化還元電位を−0.07Vに調整した前記スラリーと同体積の洗浄液を濾過器に通液して、実施例3の硫化レニウム製品を得た。
[Example 3]
Using the rhenium sulfide product obtained by the method of Example 1 as a raw material, the slurry cleaning in the slurry cleaning step 32 was performed again. The conditions of Example 2 were applied as the slurry cleaning conditions. The acid concentration during stirring and standing was approximately pH 3. When the redox potential exceeded −0.07 V, sodium hydrosulfide was added to make the redox potential −0.07 V or less. The oxidation-reduction potential during standing was less than -0.07V. After standing, the slurry was filtered with a filter, and a washing liquid having the same volume as the slurry adjusted to an acid concentration pH 3 with dilute sulfuric acid and an oxidation-reduction potential of -0.07 V with sodium hydrosulfide was passed through the filter. A rhenium sulfide product of Example 3 was obtained.

[実施例4]
実施例3の方法により得られた硫化レニウム製品を原料として、スラリー洗浄工程32のスラリー洗浄を再度行った。スラリー洗浄条件は、実施例2の条件を適用した。攪拌中および静置している間の酸濃度はおよそpH6であった。酸化還元電位は−0.3Vを超えた段階で水硫化ナトリウムを添加して、酸化還元電位を−0.3V以下とした。静置中の酸化還元電位は、−0.3V未満であった。静置後、濾過器でスラリーを濾過し、さらに希硫酸で酸濃度pH6、水硫化ナトリウムで酸化還元電位を−0.3Vに調整した前記スラリーと同体積の洗浄液を濾過器に通液して、実施例4の硫化レニウム製品を得た。
[Example 4]
Using the rhenium sulfide product obtained by the method of Example 3 as a raw material, the slurry cleaning in the slurry cleaning step 32 was performed again. The conditions of Example 2 were applied as the slurry cleaning conditions. The acid concentration during stirring and standing was approximately pH 6. When the oxidation-reduction potential exceeded -0.3 V, sodium hydrosulfide was added to make the oxidation-reduction potential -0.3 V or less. The oxidation-reduction potential during standing was less than -0.3V. After allowing to stand, the slurry was filtered with a filter, and a washing solution having the same volume as the slurry adjusted to an acid concentration pH 6 with dilute sulfuric acid and an oxidation-reduction potential of -0.3 V with sodium hydrosulfide was passed through the filter. The rhenium sulfide product of Example 4 was obtained.

[実施例5]
実施例1の方法により得られた硫化レニウム製品を原料として、スラリー洗浄工程32のスラリー洗浄を再度行った。スラリー洗浄条件は、実施例2の条件を適用した。攪拌中および静置している間の酸濃度はおよそpH3であった。酸化還元電位は−0.3Vを超えた段階で水硫化ナトリウムを添加して、酸化還元電位を−0.3V以下とした。静置中の酸化還元電位は、−0.3V未満であった。静置後、濾過器でスラリーを濾過し、さらに希硫酸で酸濃度pH3、水硫化ナトリウムで酸化還元電位を−0.3Vに調整した前記スラリーと同体積の洗浄液を濾過器に通液して、実施例5の硫化レニウム製品を得た。
[Example 5]
Using the rhenium sulfide product obtained by the method of Example 1 as a raw material, the slurry cleaning in the slurry cleaning step 32 was performed again. The conditions of Example 2 were applied as the slurry cleaning conditions. The acid concentration during stirring and standing was approximately pH 3. When the oxidation-reduction potential exceeded -0.3 V, sodium hydrosulfide was added to make the oxidation-reduction potential -0.3 V or less. The oxidation-reduction potential during standing was less than -0.3V. After allowing to stand, the slurry was filtered with a filter, and a washing liquid having the same volume as the slurry adjusted to an acid concentration pH 3 with dilute sulfuric acid and an oxidation-reduction potential of -0.3 V with sodium hydrosulfide was passed through the filter. A rhenium sulfide product of Example 5 was obtained.

[比較例1]
硫化工程31までは実施例1と同様にして硫化レニウムを含むスラリーを生成し、これを2時間静置後、全体の85体積%に相当する量を上澄み液として上部から抜き取り、残部の硫化レニウムを含むスラリーに対して、体積で10倍量の希硫酸で酸濃度1規定とした洗浄液を添加し、40分攪拌した。攪拌中の酸濃度は1.0規定であった。撹拌時および静置の間は酸化還元電位の調整は行わなかった。そのため、酸化還元電位は当初0.16Vであったが、徐々に酸化して攪拌終了時には酸化還元電位は0.4Vとなった。攪拌後はそのまま3時間静置した。攪拌中および静置中は、容器内の窒素パージをしなかった。
[Comparative Example 1]
A slurry containing rhenium sulfide was produced in the same manner as in Example 1 until the sulfiding step 31, and after standing for 2 hours, an amount corresponding to 85% by volume of the whole was extracted from the top as a supernatant, and the remaining rhenium sulfide was obtained. A cleaning solution having an acid concentration of 1 N with 10 times the volume of dilute sulfuric acid was added to the slurry containing and stirred for 40 minutes. The acid concentration during stirring was 1.0N. The redox potential was not adjusted during stirring and standing. Therefore, the oxidation-reduction potential was initially 0.16V, but gradually oxidized and the oxidation-reduction potential became 0.4V at the end of stirring. After stirring, the mixture was allowed to stand for 3 hours. The nitrogen purge inside the container was not performed during stirring and standing.

上記3時間の静置後、全体の85%に相当する量を上澄み液として上部から抜き取り、硫化レニウムがより濃縮した残部の濃縮スラリーを濾過器に通液して濾過した。得られた濾過ケーキを洗浄するため、希硫酸で酸濃度を1.0規定に調製した洗浄液を濾過器に通液した上記濃縮スラリーと同体積だけ濾過器に通液した。洗浄液の酸化還元電位は、0.4Vであった。この濾過ケーキを乾燥機で乾燥することにより比較例1の硫化レニウム製品を作製した。   After standing for 3 hours, an amount corresponding to 85% of the whole was taken out from the upper portion as a supernatant, and the remaining concentrated slurry in which rhenium sulfide was further concentrated was passed through a filter and filtered. In order to wash the obtained filter cake, a washing liquid prepared with dilute sulfuric acid to an acid concentration of 1.0 N was passed through the filter by the same volume as the concentrated slurry passed through the filter. The oxidation-reduction potential of the cleaning liquid was 0.4V. The filter cake was dried with a drier to produce a rhenium sulfide product of Comparative Example 1.

[比較例2]
硫化工程31までは実施例2と同様にして硫化レニウムを含むスラリーを生成した後、スラリー洗浄工程32では実施例2と同様のイオン交換水を実施例2と同じ量添加し、40分に代えて1時間攪拌した。その後3時間静置した。攪拌中の酸濃度はおよそpH3であった。撹拌時および静置の間は酸化還元電位の調整を行わなかった。そのため、酸化還元電位は当初0.01Vであったが、徐々に参加して攪拌終了時には酸化還元電位は0.4Vとなった。攪拌後はそのまま3時間静置した。攪拌中および静置中は、容器内の窒素パージをしなかった。
[Comparative Example 2]
After producing the slurry containing rhenium sulfide in the same manner as in Example 2 up to the sulfiding step 31, the same amount of ion-exchanged water as in Example 2 was added in the slurry washing step 32, replacing the 40 minutes. And stirred for 1 hour. Thereafter, it was allowed to stand for 3 hours. The acid concentration during stirring was approximately pH 3. The redox potential was not adjusted during stirring and standing. Therefore, the oxidation-reduction potential was initially 0.01 V. However, the oxidation-reduction potential became 0.4 V at the end of stirring by gradually participating. After stirring, the mixture was allowed to stand for 3 hours. The nitrogen purge inside the container was not performed during stirring and standing.

静置後、濾過器でスラリーを濾過し、さらに希硫酸で酸濃度pH3に調整した前記スラリーと同体積の洗浄液を濾過器に通液して、比較例2の硫化レニウム製品を得た。洗浄液の酸化還元電位は0.4Vであった。この濾過ケーキを乾燥機で乾燥することにより比較例2の硫化レニウム製品を作製した。   After standing, the slurry was filtered with a filter, and a cleaning liquid having the same volume as the slurry adjusted to an acid concentration pH 3 with diluted sulfuric acid was passed through the filter to obtain a rhenium sulfide product of Comparative Example 2. The oxidation-reduction potential of the cleaning liquid was 0.4V. The filter cake was dried with a drier to produce a rhenium sulfide product of Comparative Example 2.

[比較例3]
硫化工程31までは上記実施例1と同様にして硫化レニウムを含むスラリーを生成した後、そのスラリーをスラリー洗浄工程32で処理することなく固液分離工程33において濾過器に直接通液して硫化レニウムの濾過ケーキを得た。この濾過ケーキを乾燥機で乾燥することにより比較例3の硫化レニウム製品を作製した。
[Comparative Example 3]
A slurry containing rhenium sulfide was produced in the same manner as in Example 1 up to the sulfidation step 31, and then the slurry was directly passed through a filter in a solid-liquid separation step 33 without being treated in the slurry washing step 32, and sulfided. A rhenium filter cake was obtained. The filter cake was dried with a drier to produce a rhenium sulfide product of Comparative Example 3.

上記実施例1〜5および比較例1〜3の硫化レニウムの作製の際、洗浄後の上澄み液(比較例3の場合を除く)、濾液および硫化レニウム製品に含まれるレニウムの含有量をICP分析装置で測定してレニウム品位及びレニウム回収率を得た。その際、硫化レニウム製品中の硫化レニウムがすべて七硫化二レニウム(VII)(Re)として換算した。また、硫化レニウム比率および硫化ナトリウム比率は硫化レニウム製品の質量および硫化レニウム製品中の七硫化二レニウムの質量および硫化ナトリウムの質量から求めた。これら実施例1〜5および比較例1〜3のレニウム品位、硫化レニウム比率および回収率を下記表1に示す。 When producing rhenium sulfide in Examples 1 to 5 and Comparative Examples 1 to 3, ICP analysis was performed on the content of rhenium contained in the supernatant liquid (except in the case of Comparative Example 3), filtrate and rhenium sulfide product after washing. Rhenium quality and rhenium recovery were obtained by measuring with an apparatus. At that time, all the rhenium sulfide in the rhenium sulfide product was converted as dirhenium heptasulfide (VII) (Re 2 S 7 ). The rhenium sulfide ratio and sodium sulfide ratio were determined from the mass of the rhenium sulfide product, the mass of dirhenium heptasulfide in the rhenium sulfide product, and the mass of sodium sulfide. The rhenium quality, rhenium sulfide ratio and recovery rate of Examples 1 to 5 and Comparative Examples 1 to 3 are shown in Table 1 below.

Figure 2018162479
Figure 2018162479

上記表1の結果から、本発明の要件を満たす条件で硫化レニウムを洗浄した実施例1〜5では、レニウム品位の高い硫化レニウム製品を高い回収率で回収することができた。これに対して、硫化レニウムの洗浄は行ったものの酸化還元電位の調整を行わなかった比較例1および2では、硫化レニウム製品のレニウム品位は高くなったが回収率が悪かった。また、比較例3では硫化レニウムを洗浄しなかったため、レニウム回収率は高かったが硫化レニウム製品中のレニウム品位が低くなった。   From the results of Table 1 above, in Examples 1 to 5 in which rhenium sulfide was washed under the conditions satisfying the requirements of the present invention, rhenium sulfide products having high rhenium quality could be recovered at a high recovery rate. On the other hand, in Comparative Examples 1 and 2 in which rhenium sulfide was cleaned but the redox potential was not adjusted, the rhenium quality of the rhenium sulfide product was high, but the recovery rate was poor. In Comparative Example 3, rhenium sulfide was not washed, so the rhenium recovery rate was high, but the rhenium quality in the rhenium sulfide product was low.

1 浸出工程
2 中和浄液工程
3 レニウム回収工程
31 硫化工程
32 スラリー洗浄工程
33 固液分離工程
DESCRIPTION OF SYMBOLS 1 Leaching process 2 Neutralization liquid purification process 3 Rhenium collection process 31 Sulfurization process 32 Slurry washing process 33 Solid-liquid separation process

Claims (4)

レニウム、ヒ素及びカドミウムを含む処理対象物を酸化浸出して浸出液を得る浸出工程と、前記浸出液をアルカリで中和してヒ素及びカドミウムを含有する中和沈殿物を生成し、レニウムを含有する中和濾液から該中和沈殿物を除去する中和浄液工程と、前記中和濾液を硫化処理して該中和濾液に含まれるレニウムを硫化レニウムとして回収するレニウム回収工程とを含む硫化レニウムの回収方法であって、
前記レニウム回収工程において、前記硫化レニウムを回収する前にそのスラリーに洗浄液を加えて、2.0規定以下で且つpH7.0以下の酸濃度、および酸化還元電位(銀−塩化銀参照電極)が−0.5V以上0.2V以下の条件下で洗浄することを特徴とする硫化レニウムの回収方法。
A leaching process for obtaining a leachate by oxidizing and leaching a treatment object containing rhenium, arsenic and cadmium, and neutralizing the leachate with an alkali to produce a neutralized precipitate containing arsenic and cadmium, and containing rhenium A rhenium sulfide process comprising: a neutralization purification process for removing the neutralized precipitate from the sum filtrate; and a rhenium recovery process for sulfiding the neutralized filtrate to recover rhenium contained in the neutralized filtrate as rhenium sulfide. A collection method,
In the rhenium recovery step, before the rhenium sulfide is recovered, a washing solution is added to the slurry, so that an acid concentration of 2.0 N or less and pH 7.0 or less, and a redox potential (silver-silver chloride reference electrode) are obtained. -A method for recovering rhenium sulfide, comprising washing under conditions of 0.5 V or more and 0.2 V or less.
前記レニウム回収工程において前記硫化処理後にデカンテーションを行い、得られた上澄み液を除去した後の硫化レニウムを含むスラリーに前記洗浄液を加え、前記酸濃度および酸化還元電位の条件下で撹拌してから静置することにより洗浄することを特徴とする、請求項1に記載の硫化レニウムの回収方法。   In the rhenium recovery step, decantation is performed after the sulfurization treatment, and after the supernatant liquid is removed, the cleaning liquid is added to the slurry containing rhenium sulfide, and the mixture is stirred under the conditions of the acid concentration and the oxidation-reduction potential. 2. The method for recovering rhenium sulfide according to claim 1, wherein the cleaning is performed by standing. 前記洗浄液で洗浄された後の硫化レニウムを含むスラリーを濾過器に通液して濾過した後、該濾過器内の濾過ケーキに前記酸濃度および酸化還元電位を有する洗浄液を通液することにより洗浄することを特徴とする、請求項2に記載の硫化レニウムの回収方法。   The slurry containing rhenium sulfide after being washed with the washing liquid is passed through a filter and filtered, and then washed by passing the washing liquid having the acid concentration and oxidation-reduction potential through the filter cake in the filter. The method for recovering rhenium sulfide according to claim 2, wherein: 前記レニウム、ヒ素及びカドミウムを含む原料が、非鉄金属製錬工場から発生する亜硫酸ガスを含む排ガスを水洗する洗浄工程から排出される洗浄排液から回収したものであることを特徴とする、請求項1〜3のいずれか1項に記載の硫化レニウムの製造方法。


The raw material containing the rhenium, arsenic, and cadmium is recovered from a cleaning effluent discharged from a cleaning process of washing exhaust gas containing sulfurous acid gas generated from a non-ferrous metal smelting plant. The manufacturing method of rhenium sulfide of any one of 1-3.


JP2017058863A 2017-03-24 2017-03-24 How to recover high-purity rhenium sulfide Active JP6842041B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2017058863A JP6842041B2 (en) 2017-03-24 2017-03-24 How to recover high-purity rhenium sulfide

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2017058863A JP6842041B2 (en) 2017-03-24 2017-03-24 How to recover high-purity rhenium sulfide

Publications (2)

Publication Number Publication Date
JP2018162479A true JP2018162479A (en) 2018-10-18
JP6842041B2 JP6842041B2 (en) 2021-03-17

Family

ID=63860858

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2017058863A Active JP6842041B2 (en) 2017-03-24 2017-03-24 How to recover high-purity rhenium sulfide

Country Status (1)

Country Link
JP (1) JP6842041B2 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111004917A (en) * 2019-10-25 2020-04-14 湖南腾驰环保科技有限公司 Process for comprehensively recovering arsenic sulfide slag

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111004917A (en) * 2019-10-25 2020-04-14 湖南腾驰环保科技有限公司 Process for comprehensively recovering arsenic sulfide slag

Also Published As

Publication number Publication date
JP6842041B2 (en) 2021-03-17

Similar Documents

Publication Publication Date Title
JP6743491B2 (en) Waste acid treatment method
JP6304530B2 (en) Tellurium separation and recovery method
US20090136400A1 (en) Process for separating and recovering base metals from used hydroprocessing catalyst
JP5138737B2 (en) Method for producing waste acid gypsum
LU85385A1 (en) PROCESS FOR LEACHING SULPHIDES CONTAINING ZINC AND IRON
JP5176053B2 (en) Wet treatment method for zinc leaching residue
JP5633129B2 (en) Method for separating rhenium from solutions containing perrhenic acid
JP7016463B2 (en) How to collect tellurium
CA3048543A1 (en) Process for the selective removal of copper compounds and other impurities with respect to molybdenum and rhenium, from molybdenite concentrates
JP6377460B2 (en) Method for treating sulfate starch
JP5843069B2 (en) Tellurium separation and recovery method
JP4079018B2 (en) Method for purifying cobalt aqueous solution
JP2020105587A (en) Treatment method of acidic solution containing noble metal, selenium and tellurium
JP6233177B2 (en) Method for producing rhenium sulfide
JP6842041B2 (en) How to recover high-purity rhenium sulfide
JP4457864B2 (en) Method for recovering nickel and / or cobalt sulfide
WO2017110572A1 (en) Method for removing sulfidizing agent
JP6962017B2 (en) Waste acid treatment method
JP6724351B2 (en) How to remove sulfiding agent
JP6981206B2 (en) Nickel sulfate aqueous solution dezincification system and its method
JP7031207B2 (en) Treatment method of waste acid generated in copper smelting
JP6780563B2 (en) How to recover rhenium sulfide
JP6060877B2 (en) Method for producing rhenium-containing solution
JP3937273B2 (en) Method for treating slurry containing colloidal silica
JP7508977B2 (en) Dezincification treatment method, nickel oxide ore hydrometallurgy method

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20200129

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20210108

TRDD Decision of grant or rejection written
A01 Written decision to grant a patent or to grant a registration (utility model)

Free format text: JAPANESE INTERMEDIATE CODE: A01

Effective date: 20210119

A61 First payment of annual fees (during grant procedure)

Free format text: JAPANESE INTERMEDIATE CODE: A61

Effective date: 20210201

R150 Certificate of patent or registration of utility model

Ref document number: 6842041

Country of ref document: JP

Free format text: JAPANESE INTERMEDIATE CODE: R150