JP2004035969A - Method for refining selenium or the like - Google Patents
Method for refining selenium or the like Download PDFInfo
- Publication number
- JP2004035969A JP2004035969A JP2002196803A JP2002196803A JP2004035969A JP 2004035969 A JP2004035969 A JP 2004035969A JP 2002196803 A JP2002196803 A JP 2002196803A JP 2002196803 A JP2002196803 A JP 2002196803A JP 2004035969 A JP2004035969 A JP 2004035969A
- Authority
- JP
- Japan
- Prior art keywords
- selenium
- platinum group
- liquid
- tellurium
- group element
- 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
Links
Images
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
Abstract
Description
【０００１】
【発明の属する技術分野】
本発明は、白金族元素と共にセレンを含む滓などから、セレンを効率良く白金族元素と分離して回収することができる処理方法に関する。
【０００２】
【従来技術とその課題】
白金族元素は、銀製錬工程からでる銀アノードスライムや、このスライムに硝酸を加えて金以外の成分を浸出した後に還元して得たスライムなどを原料として回収されている。従来、これらのスライムを溶解するには、王水による溶解、または塩酸と過酸化水素による溶解、または塩酸と塩素ガス吹込みによる溶解が利用されている。
【０００３】
ところが、白金族元素と共に大量のセレンが共存している場合、これを還元して沈殿化すると白金族のセレン化物が形成される場合が多い。この白金族セレン化物は王水や塩酸および過酸化水素では溶解し難く、特に過酸化水素を使用した場合にはセレン化物の表面で過酸化水素が分解するために酸化剤としての効果が殆ど無い。このため従来の溶解法では白金族セレン化物を溶解して、白金族元素をセレンと分離するのが難しい。また、焙焼によってセレンを酸化セレンの形で気化させて原料から除去する方法では、二酸化セレンの毒性によって環境が汚染される問題がある。
【０００４】
また、銅電解澱物の金抽出後液に含まれる白金族元素とセレン・テルルとを分離する方法として、液中の塩素イオン濃度を１．５モル／Ｌ以下とし、６０℃〜９０℃の温度下で、８〜１２％濃度の亜硫酸ガスを液中に吹き込み、白金族元素を還元して沈澱化し、液中のセレンと分離した後に、さらに亜硫酸ガスを吹き込んでセレンを還元して沈澱化する方法（特開２００１−３１６７３５号）や、銅電解スライムの塩酸浸出液から溶媒抽出によって金および白金族を回収した抽出残液に二酸化硫黄を導入し、セレンおよびテルルを還元して沈澱化する方法（特許第３０８７７５８号：特開２００１−２０７２２３）などが知られている。
【０００５】
しかし、二酸化硫黄による二段階の還元処理は工程の管理が非常に難しく、しかも何れの沈澱においてもセレンまたは白金族元素の混入が避けられず、二酸化硫黄による還元だけでは分離が不十分である。また、白金族を溶媒抽出してセレンやテルルと分離する方法はコスト高であり、抽出後の回収処理も面倒である。さらに、これらの方法は何れもすでに溶液中に共存する白金族元素とセレンを分離するものであり、白金族元素とセレン等を含む処理滓の溶解に関するものではない。
【０００６】
この他にセレンやテルルの回収に関して次の方法が従来から知られている。例えば、酸化剤を用いて金属セレンを酸化し、これをアルカリ金属の炭酸塩または水酸化物で中和してアルカリ金属セレン酸塩を製造する方法（特開昭６０−１７６９０８号）、セレン含有物をアルカリ金属炭酸塩と反応させて水溶性スラリーにし、これを酸化雰囲気下で焙焼してペレットにした後に水浸出する方法（特開昭５６−５３０６号）、含テルル銅スライムを酸化剤の存在下で鉱酸に溶解し、これにアルカリを加えて銅を沈澱分離した後に、中和してテルルを沈澱化する方法（特開昭５６−８４４２８号）などが知られている。しかし、これらは何れもセレンやテルルを酸化して溶解する方法であり、この方法では白金族元素とセレンとを溶解段階で分離することができない。
【０００７】
また、セレンを蒸留して回収する方法は、毒性の強い二酸化セレン蒸気によって周囲の環境が汚染される問題がある。しかも蒸留セレンはショットやインゴットの形態で回収されるため、粉末を得るには粉砕工程が必要になる。この他に、亜硫酸ソーダを用いてセレンを浸出し、不溶解性の不純物と分離する精製方法が知られているが、９０℃以上の高温でないとセレンの浸出が進まず、しかも亜硫酸イオンの一部がチオ硫酸イオンに転換して白金族元素や銀を浸出するので、セレンの精製効果が低下すると云う問題がある。
【０００８】
本発明は、白金族元素と共存するセレン等の精製方法について、従来の上記問題を解決したものであり、セレン等を溶解段階で効率よく白金族元素と分離し、容易に回収することができるセレン等の精製方法を提供する。
【０００９】
【課題を解決する手段】
すなわち、本発明によれば以下のセレン精製方法が提供される。
（１）セレン等と白金族元素の含有物（セレン白金族含有物と云う）を高温下でアルカリ浸出してセレン等を液中に移行させ、これを固液分離して固形分に含まれる白金族元素と液分に含まれるセレン等とを分離し、分離した濾液を中和してセレン等を沈澱させることを特徴とするセレン等の精製方法。
（２）セレン白金族含有物を高温下でアルカリ浸出することによってセレンと共にテルルを液中に移行させる上記（１）の精製方法。
（３）セレン白金族含有物を、６０℃以上の温度下および１モル／Ｌ以上のアルカリ濃度下で浸出する上記（１）または（２）の精製方法。
（４）アルカリ浸出後に固液分離した濾液に硫酸を加えて中和し、セレン等を沈澱させる上記（１）〜（３）の何れかにに記載する精製方法。
（５）セレン白金族含有物を高温下でアルカリ浸出してセレン等を液中に移行させ、これを固液分離して固形分に含まれる白金族元素と液分に含まれるセレン等とを分離し、分離した濾液を中和してセレン等を沈澱させて回収する一方、分離した固形分に塩酸酸性下で酸化剤を加えて白金族元素を溶解し、白金族元素液を得るセレン等の精製方法。
（６）脱銅製錬スライムを塩酸および過酸化水素によってスラリーにし、これを濾過して主に銀を含む浸出滓と、金、白金族元素およびセレン、テルルを含む浸出液とに分離し、次に、この浸出液の液性を調整した後に溶媒抽出によって浸出液から金を分離する一方、抽出残液に二酸化イオウを添加してセレンないしテルルを沈澱させ、これを固液分離して得た濾滓を高温下でアルカリ浸出する上記（１）〜（５）の何れかに記載する溶解分離方法。
【００１０】
【発明の実施の形態】
以下、本発明を実施例と共に具体的に説明する。
本発明の処理方法の概略を図１に示す。図示するように本発明の処理方法は、セレン等と白金族元素の含有物（セレン白金族含有物）を高温下でアルカリ浸出してセレン等を液中に移行させ、これを固液分離して固形分に含まれる白金族元素と液分に含まれるセレン等とを分離し、分離した濾液を中和してセレン等を沈澱させることを特徴とするセレン等の精製方法である。
【００１１】
本発明の上記精製方法は、セレン白金族含有物を高温下でアルカリ浸出することによってセレンおよび／またはテルルを液中に移行させる方法を含む。なお、本発明において、セレン白金族含有物とは白金族元素と共にセレン等を含有するものを云い、セレン等とはセレンおよび／またはテルルを云う。
また、本発明は、セレン白金族含有物を高温下でアルカリ浸出してセレン等を液中に移行させ、これを固液分離して固形分に含まれる白金族元素と液分に含まれるセレン等とを分離し、分離した濾液を中和してセレン等を沈澱させて回収する一方、分離した固形分に塩酸酸性下で酸化剤を加えて白金族元素を溶解し、白金族元素液を得るセレン等の精製方法を含む。
【００１２】
セレン白金族含有物として、例えば、脱銅製錬スライムの塩酸浸出液から溶媒抽出によって金を分離した抽出残液の処理滓を用いることができる。この脱銅製錬スライムには金、銀、白金族元素、セレン、テルルなどの有価金属が多量に含まれている。この処理方法の一例を図２に示す。図示するように、上記脱銅スライムを塩酸および過酸化水素によってスラリーにし、これを濾過して主に銀を含む浸出滓と、金、白金族元素およびセレン、テルルを含む浸出液とに分離する。次に、この浸出液の液性を調整した後に溶媒抽出によって浸出液から金を分離する。一方、抽出残液には白金族元素、セレン、テルルが残留している。そこで、この抽出残液に二酸化イオウを添加してこれらの白金族元素、セレンおよびテルルを沈澱化し、処理滓として回収することができる。
【００１３】
なお、上記抽出残液に二酸化イオウを添加してセレンとテルルを還元し、沈澱化させる際、テルルはセレンより還元電位が低く、セレンが沈澱した後にテルルが沈澱するので、セレン沈澱を濾別した後に、この濾液にさらに二酸化イオウを添加してテルルを沈澱化することによって両者を分離回収することができる。これらの還元の際に白金族元素はセレンないしテルルと共に沈澱する。本発明はセレン白金族含有物としてこれらのセレン沈澱滓あるいはテルル沈澱滓を用いることができる。
【００１４】
セレン白金族含有物のアルカリ浸出は、１モル／Ｌ以上のアルカリ濃度下で行うのが適当であり、例えば５モル／Ｌ〜８モル／Ｌの範囲が好ましい。アルカリ濃度を１モル／Ｌ以上にすることにより、ｐＨ＞１４の強アルカリ性下でセレンやテルルの酸化還元電位が下がり、常圧下において酸化剤を用いずに、セレンおよびテルルをアルカリ溶液中に溶出させることができる。なお、常温ではこのセレンやテルルの溶出反応の進行が遅いので、６０℃以上の温度下、好ましくは８０℃程度の温度下で浸出を行うのが適当である。
【００１５】
上記アルカリ浸出によって、セレンおよびテルルはアルカリ溶液中に溶出してコロイド状に分散し、セレンを含む溶液は濃紫色を示す。一方、ロジウムやパラジウムなどの白金族元素は溶出せずに残留する。これを濾別して、セレンないしテルルの分散液と、白金族元素を含む固形分とに分離する。
【００１６】
上記固液分離後、濾液に硫酸または塩酸を加えて中和すると金属セレンないし金属テルルの黒色沈澱を生じ、溶液の色が濃紫色から次第に薄くなり、ｐＨ７付近で液は透明になる。このセレン沈澱ないしテルル沈澱の品位は概ね９９％以上であり、高品位の金属セレンないし金属テルルを回収することができる。なお、硫酸や塩酸に代えて硝酸を用いると、硝酸の酸化力によってセレンやテルルは酸化溶解するので沈殿化することができない。
【００１７】
上記固液分離後、濾別した固形分に過酸化水素などの酸化剤を塩酸と共に添加し、白金、パラジウム、ロジウム、ルテニウムなどの白金族元素を溶出させる。白金族元素は過酸化水素によって酸化されると共に塩素イオンによって塩化物錯体となり、安定化されて液中に溶出する。過酸化水素は白金族元素を安定な酸化数のイオンにするために必要な当量、すなわち白金を４価、バラジウムを２価、ロジウムおよびルテニウムを３価に酸化するのに必要な当量を用いる。塩酸はそれぞれＰｔＣｌ６ −，ＰｄＣｌ４ −，ＲｈＣｌ６ ３−，ＲｕＣｌ６ ３−に相当する量、および遊離塩酸として２モル／Ｌ以上を用いる。反応温度は反応を促進するため６０℃以上が良く、また過酸化水素の分解を抑制するため８０℃以下が適当であり、７０℃程度の温度下で行うのが好ましい。この溶解処理によって、白金、パラジウム、ロジウム、ルテニウムなどが溶解した塩酸性溶液を得ることができる。
【００１８】
【発明の効果】
本発明の処理方法によれば、セレン白金族含有物を６０℃〜８０℃程度の処理温度においてアルカリ浸出することによって、常圧下で酸化剤を用いずに、セレンやテルルを溶解して白金族元素から分離することができる。この溶出したセレンやテルルはコロイド状に分散しており、浸出液を中和するとメタルになって沈澱するので、高品位のセレンおよびテルルを概ね９５％以上の収率で回収することができる。因みに、従来の酸化剤を用いてアルカリ浸出する方法は加圧下で浸出を行い、セレン酸ソーダないし亜セレン酸ソーダなどが生じるので、その後のセレン回収工程が面倒である。一方、本発明の処理方法は常圧下で酸化剤を用いずにセレンおよびテルルを溶解して白金族元素と分離するので工程の管理および回収処理が容易である。
【００１９】
【実施例および比較例】
〔実施例１〕
金、セレンおよびテルル、白金族を含む銅電解スライム２００ｋｇを過酸化水素の存在下で塩酸浸出した。浸出液の塩酸濃度を１．５モル／Ｌに調整して金抽出溶媒（ジブチルカルビートル：ＤＢＣ）に接触させ、金を抽出して有機相と水相に分離した。この水相に亜硫酸ガスを導入し、液中のセレン濃度が５ｇ／Ｌになるまで還元してセレンを沈澱させた。このセレン沈澱を回収して不純物を分析したところ、白金族元素以外は全て５０ｐｐｍ以下であった。このセレン滓１ｇを５モル／Ｌの苛性ソーダ溶液１０リットルと混合し、８０℃に保持してアルカリ浸出を行ったところ、濃紫色の溶液を得た。冷却後、濾過して残渣を分析したところ、パラジウムおよび白金が主成分であった。一方、濾液を再び８０℃に保ち、硫酸を加えて中和していくと、黒色沈澱が生じ始め、ｐＨ７付近で液が透明になった。この沈澱を濾別して回収し、成分を分析したところ、品位９９．９％の金属セレンであった。なお、６０℃〜１００℃でアルカリ浸出を行った場合も同様であり、７０〜９８％の収率でセレンを回収することができた。
【００２０】
〔比較例１、２〕
実施例において、セレン滓に苛性ソーダを加え、室温４０℃に保持したところセレンは溶解しなかった（比較例１）。また、実施例において、濾液を４０℃に保って硫酸を添加したところ、赤いガラス状のセレンが沈澱し、濾過が困難であった（比較例２）。
【００２１】
〔実施例２〕
金、セレンおよびテルル、白金族を含む銅電解スライム２００ｋｇを過酸化水素の存在下で塩酸浸出した。浸出液の塩酸濃度を１．５モル／Ｌに調整して金抽出溶媒（ジブチルカルビートル：ＤＢＣ）に接触させ、金を抽出して有機相と水相に分離した。この水相に亜硫酸ガスを導入し、液中のセレン濃度が０ｇ／Ｌ、ＯＲＰ４００ｍＶ（ｖｓ Ａｇ／ＡｇＣｌ）になるまで還元してセレンを沈澱させた。このセレン沈澱を濾別し、この濾液にさらに亜硫酸ガスを吹き込み、液中のテルル濃度が０ｇ／Ｌ、ＯＲＰ３００ｍＶになるまで還元してテルルを沈殿させた。このテルル沈殿を回収して不純物を分析したところ、白金族元素以外は全て５０ｐｐｍ以下であった。このテルル沈殿１ｋｇを５モル／Ｌの苛性ソーダ溶液１０Ｌと混合し、８０℃に保持したところ、大部分は液中に溶解し、液は濃い紫色になった．冷却後に濾過し、残渣を分析したところＰｄ、Ｒｈ、Ｒｕが主成分であった。濾液を再び８０℃に保ちながら硫酸を加えて中和していくと黒い沈毅が生じ始め、ｐＨが７付近で液が透明になった。この沈殿を濾別回収して分析したところ、品位９９．９％の金属テルルであった。
【００２２】
〔実施例３〕
金、セレンおよびテルル、白金族を含む銅電解スライム２００ｋｇを過酸化水素の存在下で塩酸浸出した。浸出液の塩酸濃度を１．５モル／Ｌに調整して金抽出溶媒（ジブチルカルビートル：ＤＢＣ）に接触させ、金を抽出して有機相と水相に分離した。この水相に亜硫酸ガスを導入し、液中のセレン濃度が５ｇ／Ｌになるまで還元してセレンを沈澱させた。このセレン沈澱を回収して不純物を分析したところ、白金族元素以外は全て５０ｐｐｍ以下であった。このセレン滓１ｇを５モル／Ｌの苛性ソーダ溶液１０リットルと混合し、８０℃に保持してアルカリ浸出を行ったところ、濃紫色の溶液を得た。冷却後、濾過して残渣を分析したところ、Ｐｄ：８５％、Ｐｔ：９％、Ｒｈ：１％であった。濾液を再び８０℃に保ちながら硫酸を加えて中和していくと黒い沈殿が生じ始め、ｐＨ７付近で液が透明になった。この沈殿を濾別して分析したところ、品位９９．９％の金属セレンであった。この残渣を塩酸４００ｍｌおよび水１００ｍｌでリパルプし、液温を７０℃に保ちながら過酸化水素１２０ｍｌを徐々に添加した。これを冷却して濾過し、濾液を分析したところ、Ｐｄ：８０ｇ／Ｌ、Ｐｔ：８ｇ／Ｌ、Ｒｈ：０．９ｇ／Ｌであった。
【図面の簡単な説明】
【図１】本発明の処理方法の概略を示す工程図。
【図２】脱銅スライムの処理から本発明の処理方法に至る概略を示す工程図。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a treatment method capable of efficiently separating and recovering selenium from platinum group elements from selenium containing selenium together with platinum group elements.
[0002]
[Prior art and its problems]
Platinum group elements are recovered as silver anode slime from a silver smelting process or slime obtained by leaching components other than gold by adding nitric acid to the slime and reducing the slime. Conventionally, to dissolve these slimes, dissolution with aqua regia, dissolution with hydrochloric acid and hydrogen peroxide, or dissolution by blowing hydrochloric acid and chlorine gas has been used.
[0003]
However, when a large amount of selenium coexists with a platinum group element, when this is reduced and precipitated, platinum group selenide is often formed. This platinum group selenide hardly dissolves in aqua regia, hydrochloric acid, and hydrogen peroxide.Especially, when hydrogen peroxide is used, hydrogen peroxide decomposes on the surface of the selenide, so it has almost no effect as an oxidizing agent. . Therefore, it is difficult to dissolve the platinum group selenide and separate the platinum group element from selenium by the conventional dissolving method. Further, in the method of removing selenium from raw materials by vaporizing selenium in the form of selenium oxide by roasting, there is a problem that the toxicity of selenium dioxide pollutes the environment.
[0004]
In addition, as a method of separating the platinum group element and selenium / tellurium contained in the solution after the gold extraction of the copper electrolytic deposit, the chloride ion concentration in the solution is set to 1.5 mol / L or less, At a temperature, sulfuric acid gas having a concentration of 8 to 12% is blown into the liquid to precipitate and reduce the platinum group element. After separating from the selenium in the liquid, selenium is further blown into the liquid to precipitate the selenium. (Japanese Patent Application Laid-Open No. 2001-316735) or a method in which sulfur dioxide is introduced into an extraction residue obtained by recovering gold and platinum groups from a hydrochloric acid leachate of copper electrolytic slime by solvent extraction, and selenium and tellurium are reduced to precipitate. (Japanese Patent No. 3087758: JP-A-2001-207223) and the like are known.
[0005]
However, the two-stage reduction treatment with sulfur dioxide is very difficult to control the process, and selenium or a platinum group element is inevitably mixed in any of the precipitations, so that separation by sulfur dioxide alone is insufficient. Further, the method of extracting the platinum group with a solvent to separate it from selenium or tellurium is expensive, and the recovery process after the extraction is troublesome. Furthermore, all of these methods separate the platinum group element and selenium which are already present in the solution, and do not relate to the dissolution of the processing residue containing the platinum group element and selenium.
[0006]
In addition to the above, the following methods are conventionally known for recovering selenium and tellurium. For example, a method of producing alkali metal selenate by oxidizing metal selenium using an oxidizing agent and neutralizing the metal selenium with an alkali metal carbonate or hydroxide (Japanese Patent Application Laid-Open No. 60-176908). By reacting the product with an alkali metal carbonate to form a water-soluble slurry, roasting it in an oxidizing atmosphere to form pellets, and leaching with water (JP-A-56-5306). A method of dissolving in a mineral acid in the presence of, adding an alkali thereto to precipitate and separate copper, and then neutralizing to precipitate tellurium (JP-A-56-84428) is known. However, each of these methods is a method of oxidizing and dissolving selenium or tellurium, and this method cannot separate the platinum group element and selenium in the dissolving stage.
[0007]
Further, the method of recovering selenium by distillation has a problem that the surrounding environment is polluted by highly toxic selenium dioxide vapor. Moreover, since distilled selenium is recovered in the form of shots and ingots, a pulverizing step is required to obtain powder. In addition, a purification method is known in which selenium is leached using sodium sulfite to separate it from insoluble impurities. However, selenium leaching does not proceed unless the temperature is higher than 90 ° C. Since the part is converted to thiosulfate ion and leaches the platinum group element and silver, there is a problem that the purification effect of selenium is reduced.
[0008]
The present invention solves the above-mentioned conventional problems with respect to a method for purifying selenium or the like coexisting with a platinum group element, and selenium or the like can be efficiently separated from a platinum group element in a dissolution step and easily recovered. A method for purifying selenium and the like is provided.
[0009]
[Means to solve the problem]
That is, according to the present invention, the following selenium purification method is provided.
(1) Alkaline leaching of a substance containing selenium and the like and a platinum group element (referred to as selenium platinum group containing substance) at a high temperature to transfer selenium and the like into a liquid, which is separated into a solid and a liquid and contained in a solid content A method for purifying selenium or the like, comprising separating a platinum group element from selenium and the like contained in a liquid component, and neutralizing the separated filtrate to precipitate selenium and the like.
(2) The purification method according to (1) above, wherein tellurium is transferred together with selenium into the liquid by leaching the selenium platinum group-containing substance at an elevated temperature with an alkali.
(3) The purification method according to the above (1) or (2), wherein the selenium platinum group-containing substance is leached at a temperature of 60 ° C. or more and an alkali concentration of 1 mol / L or more.
(4) The purification method according to any one of the above (1) to (3), wherein sulfuric acid is added to the filtrate, which has been subjected to solid-liquid separation after alkali leaching, and neutralized by adding sulfuric acid to precipitate selenium and the like.
(5) Alkaline leaching of the selenium platinum group-containing material at a high temperature to transfer selenium and the like into the liquid, and then separating the selenium and the like into solid and liquid to separate the platinum group element contained in the solid and the selenium contained in the liquid Separated, the separated filtrate is neutralized to precipitate selenium, etc., and recovered.On the other hand, an oxidizing agent is added to the separated solid under acidification with hydrochloric acid to dissolve the platinum group element to obtain a platinum group element solution. Purification method.
(6) The copper-free smelting slime is slurried with hydrochloric acid and hydrogen peroxide, which is filtered to separate into a leach slag containing mainly silver and a leaching solution containing gold, platinum group elements and selenium and tellurium, After adjusting the liquid properties of the leachate, gold was separated from the leachate by solvent extraction, while sulfur dioxide was added to the extraction residue to precipitate selenium or tellurium, and the filter cake obtained by solid-liquid separation of the sediment was removed. The dissolution separation method according to any one of the above (1) to (5), wherein alkali leaching is performed at a high temperature.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the present invention will be specifically described with examples.
FIG. 1 shows an outline of the processing method of the present invention. As shown in the figure, in the treatment method of the present invention, a selenium or the like and a substance containing a platinum group element (a selenium / platinum group containing substance) are leached with an alkali at a high temperature to transfer the selenium or the like into a liquid, which is separated into a solid and a liquid. And separating a platinum group element contained in a solid content from selenium and the like contained in a liquid component, and neutralizing the separated filtrate to precipitate selenium and the like.
[0011]
The purification method of the present invention includes a method of transferring selenium and / or tellurium into a liquid by subjecting a selenium platinum group-containing substance to alkaline leaching at a high temperature. In the present invention, the selenium-platinum-group-containing substance refers to a substance containing selenium or the like together with a platinum-group element, and the selenium or the like refers to selenium and / or tellurium.
In addition, the present invention provides an alkaline leaching of a selenium platinum group-containing substance at a high temperature to transfer selenium or the like into a liquid, and then separates the selenium or the like into a liquid by solid-liquid separation. And the separated filtrate is neutralized to precipitate selenium, etc., and recovered.On the other hand, an oxidizing agent is added to the separated solid under acidic hydrochloric acid to dissolve the platinum group element, and the platinum group element solution is separated. Includes methods for purifying selenium and the like obtained.
[0012]
As the selenium platinum group-containing material, for example, a treated slag of an extraction residue obtained by separating gold from a hydrochloric acid leachate of a copper-free smelting slime by solvent extraction can be used. This decopper smelting slime contains a large amount of valuable metals such as gold, silver, platinum group elements, selenium and tellurium. FIG. 2 shows an example of this processing method. As shown in the figure, the decopperized slime is slurried with hydrochloric acid and hydrogen peroxide, and filtered to separate into a leaching slag containing mainly silver and a leaching solution containing gold, a platinum group element and selenium and tellurium. Next, after adjusting the liquid properties of the leachate, gold is separated from the leachate by solvent extraction. On the other hand, a platinum group element, selenium, and tellurium remain in the extraction residue. Then, sulfur dioxide is added to the residual extract to precipitate these platinum group elements, selenium and tellurium, and can be recovered as treated slag.
[0013]
In addition, when sulfur dioxide is added to the above extraction residue to reduce selenium and tellurium and precipitate, tellurium has a lower reduction potential than selenium, and tellurium precipitates after selenium precipitates. After the addition, sulfur dioxide is further added to the filtrate to precipitate tellurium, whereby both can be separated and recovered. During these reductions, the platinum group elements precipitate with selenium or tellurium. In the present invention, these selenium precipitates or tellurium precipitates can be used as the selenium platinum group-containing material.
[0014]
The alkali leaching of the selenium platinum group-containing substance is suitably performed at an alkali concentration of 1 mol / L or more, for example, preferably in the range of 5 mol / L to 8 mol / L. By increasing the alkali concentration to 1 mol / L or more, the oxidation-reduction potential of selenium and tellurium is reduced under strong alkalinity of pH> 14, and selenium and tellurium are eluted in an alkaline solution without using an oxidizing agent under normal pressure. Can be done. Since the elution reaction of selenium and tellurium proceeds slowly at normal temperature, it is appropriate to perform leaching at a temperature of 60 ° C. or more, preferably at a temperature of about 80 ° C.
[0015]
Due to the alkali leaching, selenium and tellurium are eluted and dispersed in a colloidal form in the alkaline solution, and the solution containing selenium exhibits a deep purple color. On the other hand, platinum group elements such as rhodium and palladium remain without being eluted. This is separated by filtration to separate into a dispersion of selenium or tellurium and a solid containing a platinum group element.
[0016]
After the solid-liquid separation, when the filtrate is neutralized by adding sulfuric acid or hydrochloric acid, a black precipitate of selenium metal or tellurium metal is generated, the color of the solution gradually decreases from deep purple, and the solution becomes transparent at around pH 7. The grade of the selenium precipitate or tellurium precipitate is about 99% or more, and high-grade metal selenium or tellurium can be recovered. If nitric acid is used instead of sulfuric acid or hydrochloric acid, selenium or tellurium is oxidized and dissolved by the oxidizing power of nitric acid, so that precipitation cannot be performed.
[0017]
After the solid-liquid separation, an oxidizing agent such as hydrogen peroxide is added to the filtered solid content together with hydrochloric acid to elute platinum group elements such as platinum, palladium, rhodium and ruthenium. The platinum group element is oxidized by hydrogen peroxide and becomes a chloride complex by chlorine ions, stabilized, and eluted in the liquid. Hydrogen peroxide is used in an equivalent amount necessary to convert the platinum group element into an ion having a stable oxidation number, that is, an equivalent amount necessary to oxidize platinum to tetravalent, baradium to divalent, and rhodium and ruthenium to trivalent. Each hydrochloride PtCl 6 -, PdCl 4 -, RhCl 6 3-, amount equivalent to RuCl 6 3-, and using the above 2 mol / L as the free hydrochloric acid. The reaction temperature is preferably 60 ° C. or higher to promote the reaction, and is preferably 80 ° C. or lower to suppress the decomposition of hydrogen peroxide, and is preferably performed at a temperature of about 70 ° C. By this dissolution treatment, a hydrochloric acid solution in which platinum, palladium, rhodium, ruthenium and the like are dissolved can be obtained.
[0018]
【The invention's effect】
According to the treatment method of the present invention, the selenium or tellurium is dissolved under normal pressure without using an oxidizing agent by subjecting the selenium platinum group-containing material to alkali leaching at a treatment temperature of about 60 ° C. to 80 ° C. Can be separated from elements. The eluted selenium and tellurium are dispersed in a colloidal state, and when the leachate is neutralized, it precipitates as a metal, so that high-quality selenium and tellurium can be recovered with a yield of about 95% or more. Incidentally, in the conventional method of leaching with an alkali using an oxidizing agent, leaching is performed under pressure, and sodium selenate or sodium selenite is generated, so that the subsequent selenium recovery step is troublesome. On the other hand, the treatment method of the present invention dissolves selenium and tellurium at normal pressure without using an oxidizing agent and separates the selenium and tellurium from the platinum group element, so that the process can be easily controlled and recovered.
[0019]
[Examples and Comparative Examples]
[Example 1]
200 kg of copper electrolytic slime containing gold, selenium, tellurium, and platinum group was leached with hydrochloric acid in the presence of hydrogen peroxide. The hydrochloric acid concentration of the leachate was adjusted to 1.5 mol / L and brought into contact with a gold extraction solvent (dibutyl carbitol: DBC) to extract gold and separate it into an organic phase and an aqueous phase. Sulfurous acid gas was introduced into the aqueous phase, and the mixture was reduced until the selenium concentration in the liquid became 5 g / L to precipitate selenium. When this selenium precipitate was recovered and analyzed for impurities, it was found to be 50 ppm or less for all but the platinum group elements. 1 g of this selenium slag was mixed with 10 liters of a 5 mol / L caustic soda solution, and alkali leaching was performed at 80 ° C., to obtain a dark purple solution. After cooling, filtration and analysis of the residue revealed that palladium and platinum were the main components. On the other hand, when the filtrate was kept at 80 ° C. again and neutralized by adding sulfuric acid, a black precipitate began to form, and the solution became transparent at around pH 7. The precipitate was collected by filtration, and the components were analyzed. The result was 99.9% grade metal selenium. The same applies to the case where alkali leaching was performed at 60 ° C. to 100 ° C., and selenium was recovered with a yield of 70 to 98%.
[0020]
[Comparative Examples 1 and 2]
In the examples, selenium did not dissolve when caustic soda was added to selenium slag and kept at room temperature of 40 ° C. (Comparative Example 1). Further, in Example, when the filtrate was kept at 40 ° C. and sulfuric acid was added, red glassy selenium was precipitated and filtration was difficult (Comparative Example 2).
[0021]
[Example 2]
200 kg of copper electrolytic slime containing gold, selenium, tellurium, and platinum group was leached with hydrochloric acid in the presence of hydrogen peroxide. The hydrochloric acid concentration of the leachate was adjusted to 1.5 mol / L and brought into contact with a gold extraction solvent (dibutyl carbitol: DBC) to extract gold and separate it into an organic phase and an aqueous phase. Sulfurous acid gas was introduced into this aqueous phase, and the selenium concentration was reduced to 0 g / L and the ORP was reduced to 400 mV (vs Ag / AgCl) to precipitate selenium. The selenium precipitate was separated by filtration, and sulfuric acid gas was further blown into the filtrate to reduce the tellurium concentration in the solution to 0 g / L and ORP 300 mV to precipitate tellurium. When this tellurium precipitate was recovered and analyzed for impurities, it was found to be 50 ppm or less for all but the platinum group elements. When 1 kg of this tellurium precipitate was mixed with 10 L of a 5 mol / L caustic soda solution and kept at 80 ° C., most of the tellurium dissolved in the liquid, and the liquid turned deep purple. After cooling, filtration and analysis of the residue revealed that Pd, Rh and Ru were the main components. When the filtrate was kept at 80 ° C. again and neutralized by adding sulfuric acid, black sediment began to form, and the solution became transparent when the pH was around 7. When this precipitate was collected by filtration and analyzed, it was found to be 99.9% metallic tellurium.
[0022]
[Example 3]
200 kg of copper electrolytic slime containing gold, selenium, tellurium, and platinum group was leached with hydrochloric acid in the presence of hydrogen peroxide. The hydrochloric acid concentration of the leachate was adjusted to 1.5 mol / L and brought into contact with a gold extraction solvent (dibutyl carbitol: DBC) to extract gold and separate it into an organic phase and an aqueous phase. Sulfurous acid gas was introduced into the aqueous phase, and the mixture was reduced until the selenium concentration in the liquid became 5 g / L to precipitate selenium. When this selenium precipitate was recovered and analyzed for impurities, it was found to be 50 ppm or less for all but the platinum group elements. 1 g of this selenium slag was mixed with 10 liters of a 5 mol / L caustic soda solution, and alkali leaching was performed at 80 ° C., to obtain a dark purple solution. After cooling, the residue was analyzed by filtration and found to be 85% Pd, 9% Pt, and 1% Rh. When the filtrate was maintained at 80 ° C. again and neutralized by adding sulfuric acid, a black precipitate started to form, and the solution became transparent at around pH 7. This precipitate was separated by filtration and analyzed, and it was found to be 99.9% grade metal selenium. The residue was repulped with 400 ml of hydrochloric acid and 100 ml of water, and 120 ml of hydrogen peroxide was gradually added while maintaining the liquid temperature at 70 ° C. This was cooled and filtered, and the filtrate was analyzed to find that Pd was 80 g / L, Pt was 8 g / L, and Rh was 0.9 g / L.
[Brief description of the drawings]
FIG. 1 is a process chart showing an outline of a processing method of the present invention.
FIG. 2 is a process chart showing an outline from the treatment of copper removal slime to the treatment method of the present invention.
Claims (6)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002196803A JP4134613B2 (en) | 2002-07-05 | 2002-07-05 | Purification method for selenium, etc. |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002196803A JP4134613B2 (en) | 2002-07-05 | 2002-07-05 | Purification method for selenium, etc. |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2004035969A true JP2004035969A (en) | 2004-02-05 |
| JP4134613B2 JP4134613B2 (en) | 2008-08-20 |
Family
ID=31704740
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002196803A Expired - Fee Related JP4134613B2 (en) | 2002-07-05 | 2002-07-05 | Purification method for selenium, etc. |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP4134613B2 (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012082251A1 (en) * | 2010-12-17 | 2012-06-21 | General Electric Company | Selenium separation and recovery from bioreactor sludge |
| JP2013256419A (en) * | 2012-06-13 | 2013-12-26 | Mitsubishi Materials Corp | Method for separating and recovering tellurium |
| JP2015113267A (en) * | 2013-12-13 | 2015-06-22 | 三菱マテリアル株式会社 | Separation/recovery method of tellurium |
| JP2015193888A (en) * | 2014-03-31 | 2015-11-05 | 三菱マテリアル株式会社 | Recovery method of platinum group element |
| JP2018115380A (en) * | 2017-01-19 | 2018-07-26 | 三菱マテリアル株式会社 | Method for separating tellurium and platinum group metal |
| JP2020105587A (en) * | 2018-12-27 | 2020-07-09 | Ｊｘ金属株式会社 | Treatment method of acidic solution containing noble metal, selenium and tellurium |
-
2002
- 2002-07-05 JP JP2002196803A patent/JP4134613B2/en not_active Expired - Fee Related
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012082251A1 (en) * | 2010-12-17 | 2012-06-21 | General Electric Company | Selenium separation and recovery from bioreactor sludge |
| JP2013256419A (en) * | 2012-06-13 | 2013-12-26 | Mitsubishi Materials Corp | Method for separating and recovering tellurium |
| JP2015113267A (en) * | 2013-12-13 | 2015-06-22 | 三菱マテリアル株式会社 | Separation/recovery method of tellurium |
| JP2015193888A (en) * | 2014-03-31 | 2015-11-05 | 三菱マテリアル株式会社 | Recovery method of platinum group element |
| JP2018115380A (en) * | 2017-01-19 | 2018-07-26 | 三菱マテリアル株式会社 | Method for separating tellurium and platinum group metal |
| JP2020105587A (en) * | 2018-12-27 | 2020-07-09 | Ｊｘ金属株式会社 | Treatment method of acidic solution containing noble metal, selenium and tellurium |
| JP7198079B2 (en) | 2018-12-27 | 2022-12-28 | Ｊｘ金属株式会社 | Method for treating acidic liquids containing precious metals, selenium and tellurium |
Also Published As
| Publication number | Publication date |
|---|---|
| JP4134613B2 (en) | 2008-08-20 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100956050B1 (en) | Method for separating platinum group element | |
| NO158106B (en) | PROCEDURE FOR TREATING Aqueous SOLUTION CONTAINING Precious Metals and Undesirable Elements. | |
| JP5825484B2 (en) | Method for recovering platinum group metals | |
| US6579504B1 (en) | Hydrometallurgical treatment process for extraction of platinum group metals obviating the matte smelting process | |
| JP4866732B2 (en) | Anode sludge treatment method | |
| JP2012246198A (en) | Method for purifying selenium by wet process | |
| JP4470749B2 (en) | Rhodium recovery method and metal rhodium production method | |
| EP1577408B2 (en) | Method for separating platinum group elements from selenum/tellurium bearing materials | |
| JP4016680B2 (en) | Method for dissolving selenium platinum group element-containing material | |
| JP4134613B2 (en) | Purification method for selenium, etc. | |
| JP7198079B2 (en) | Method for treating acidic liquids containing precious metals, selenium and tellurium | |
| JP4281534B2 (en) | Treatment method for platinum group-containing materials | |
| JP4158706B2 (en) | Processing method and manufacturing method for separating gold from platinum group-containing solution | |
| JP4269586B2 (en) | Methods for separating platinum group elements | |
| JP6264566B2 (en) | Method for producing leaching product liquid containing platinum group element | |
| JP4269693B2 (en) | Process for treating selenium mixture | |
| JP2020105588A (en) | Treatment method of mixture containing noble metal, selenium and tellurium | |
| JP7247050B2 (en) | Method for treating selenosulfuric acid solution | |
| JP2018044201A (en) | Method of treating metal-containing hydrochloric acidic liquid | |
| JP2011208248A (en) | Method for separating platinum group element | |
| JPS646254B2 (en) | ||
| JP2021025069A (en) | Method of treating seleno sulfate solution | |
| JP7423467B2 (en) | Ruthenium recovery method | |
| JP2019189891A (en) | Method for separating selenium and tellurium from mixture containing selenium and tellurium | |
| JPH10158752A (en) | Method for extracting and recovering silver |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20050318 |
|
| A977 | Report on retrieval |
Free format text: JAPANESE INTERMEDIATE CODE: A971007 Effective date: 20061017 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20061024 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20061225 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20070327 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20070330 |
|
| 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: 20080507 |
|
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20080520 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110613 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110613 Year of fee payment: 3 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110613 Year of fee payment: 3 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120613 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120613 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130613 Year of fee payment: 5 |
|
| LAPS | Cancellation because of no payment of annual fees |