JPS5964721A - Separation of silver from waste film - Google Patents
Separation of silver from waste filmInfo
- Publication number
- JPS5964721A JPS5964721A JP17240482A JP17240482A JPS5964721A JP S5964721 A JPS5964721 A JP S5964721A JP 17240482 A JP17240482 A JP 17240482A JP 17240482 A JP17240482 A JP 17240482A JP S5964721 A JPS5964721 A JP S5964721A
- Authority
- JP
- Japan
- Prior art keywords
- silver
- waste film
- separating
- solution
- film
- 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.)
- Pending
Links
- 229910052709 silver Inorganic materials 0.000 title claims abstract description 80
- 239000004332 silver Substances 0.000 title claims abstract description 80
- 239000002699 waste material Substances 0.000 title claims abstract description 43
- 238000000926 separation method Methods 0.000 title description 6
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 78
- 238000000034 method Methods 0.000 claims abstract description 26
- HSJPMRKMPBAUAU-UHFFFAOYSA-N cerium(3+);trinitrate Chemical compound [Ce+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O HSJPMRKMPBAUAU-UHFFFAOYSA-N 0.000 claims description 10
- 238000006243 chemical reaction Methods 0.000 claims description 5
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000002184 metal Substances 0.000 claims description 2
- 238000006467 substitution reaction Methods 0.000 claims description 2
- 238000000354 decomposition reaction Methods 0.000 claims 1
- 238000001556 precipitation Methods 0.000 claims 1
- 229920000159 gelatin Polymers 0.000 abstract description 15
- 235000019322 gelatine Nutrition 0.000 abstract description 15
- 229920000728 polyester Polymers 0.000 abstract description 8
- 238000005868 electrolysis reaction Methods 0.000 abstract description 7
- 238000001914 filtration Methods 0.000 abstract description 2
- AKHNMLFCWUSKQB-UHFFFAOYSA-L sodium thiosulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=S AKHNMLFCWUSKQB-UHFFFAOYSA-L 0.000 abstract description 2
- 235000019345 sodium thiosulphate Nutrition 0.000 abstract description 2
- 239000001828 Gelatine Substances 0.000 abstract 2
- 239000013043 chemical agent Substances 0.000 abstract 1
- 239000000243 solution Substances 0.000 description 20
- 108010010803 Gelatin Proteins 0.000 description 13
- 239000008273 gelatin Substances 0.000 description 13
- 235000011852 gelatine desserts Nutrition 0.000 description 13
- 229910021607 Silver chloride Inorganic materials 0.000 description 5
- HKZLPVFGJNLROG-UHFFFAOYSA-M silver monochloride Chemical compound [Cl-].[Ag+] HKZLPVFGJNLROG-UHFFFAOYSA-M 0.000 description 5
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 238000003756 stirring Methods 0.000 description 3
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 2
- 230000002776 aggregation Effects 0.000 description 2
- 239000002585 base Substances 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 238000009991 scouring Methods 0.000 description 2
- 229910001220 stainless steel Inorganic materials 0.000 description 2
- 239000010935 stainless steel Substances 0.000 description 2
- 229920000742 Cotton Polymers 0.000 description 1
- HCHKCACWOHOZIP-UHFFFAOYSA-N Zinc Chemical compound [Zn] HCHKCACWOHOZIP-UHFFFAOYSA-N 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 238000004220 aggregation Methods 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
- 239000010931 gold Substances 0.000 description 1
- 229910052737 gold Inorganic materials 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 229920006267 polyester film Polymers 0.000 description 1
- -1 silver halide Chemical class 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 210000002784 stomach Anatomy 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 210000002700 urine Anatomy 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 229910052725 zinc Inorganic materials 0.000 description 1
- 239000011701 zinc Substances 0.000 description 1
Landscapes
- Silver Salt Photography Or Processing Solution Therefor (AREA)
- Manufacture And Refinement Of Metals (AREA)
Abstract
Description
【発明の詳細な説明】
本発明１ｆ−１使用後の写真フィルム、即ち廃フィルム
から銀を回収するための銀の分離方法に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention 1f-1 relates to a silver separation method for recovering silver from used photographic film, ie, waste film.
従来、廃フィルムから銀を分離する方法としては、廃フ
ィルムを炉内で焼却１．て灰分として銀を回収する焼却
方法、強アルカリ溶液中に廃フィルムを浸イ責してフィ
ルム表面のゼラチンと７・ロゲン化銀を分離するアルカ
リ処理方法があったが、これらの方法では設備上および
公害の点で種々の欠点があった。このような従来技術の
問題点を解消するものとして、近年、廃フィルムを液体
とともに破砕することによって銀を分ｉ’ｉｌ［する方
法（特開昭５７−７６１５９）が開発されたが、この方
法ではフィルムベースたるポリエステルからセラチンと
共に銀を剥離し、さらに次の段階としてゼラチンから銀
を分離するものであり、ゼラチンからの銀の分離は焼却
方法またはアルカリ処理方法などの従来公知の分離方法
でなされた。、廃フ４）レムからの銀の分離においては
、ポリニスデルからのゼラチンと銀の分離よりも、ゼラ
チンからの銀の分離が困難であり、上記のように破砕に
より先ずポリエステルとゼラチンおよび銀とを分離すれ
ば公害が少ない点で好ましいが、ゼラチンからの銀の分
離という困難な作業が残されている。Conventionally, methods for separating silver from waste film include incinerating the waste film in a furnace.1. There are two methods: an incineration method in which the silver is recovered as ash, and an alkaline treatment method in which the waste film is immersed in a strong alkaline solution to separate the gelatin and silver halide on the film surface, but these methods require equipment limitations. and had various drawbacks in terms of pollution. In order to solve these problems in the conventional technology, a method (Japanese Unexamined Patent Publication No. 57-76159) has been developed in recent years in which silver is separated by crushing the waste film together with a liquid. In this method, silver is removed together with seratin from the polyester film base, and the next step is to separate silver from gelatin. Silver is separated from gelatin by conventionally known separation methods such as incineration or alkali treatment. Ta. , waste film 4) In the separation of silver from gelatin, it is more difficult to separate silver from gelatin than from polynisdel, and as described above, the polyester, gelatin and silver are first separated by crushing. Separation would be preferable since it would cause less pollution, but the difficult task of separating silver from gelatin remains.
不発明喧公害を生じないと共に、ゼラチンからの銀の分
離という困難な作業を伴なわないで廃フィルムから銀を
６易に分離し得る銀の分離方法を提供することである。An object of the present invention is to provide a method for separating silver easily from waste film without causing pollution or causing any trouble and without involving the difficult work of separating silver from gelatin.
本発明による廃フィルムからの銀の分離方法においては
、廃フィルムに含まれる銀をＭ ｉＱ’４ Ｌ、てイオ
ン化するため溶液中に廃フィルムを浸漬することが行な
われる。その際、廃フィルムと溶液の接触を良ぐするた
め、槽内を攪拌することが好ましい。その溶液とＩ−で
は銀を溶解し得る薬剤を含むものであね、ばよく、好ま
しくはチオ硫酸ソーダを含む溶液、所謂定着液が用いら
れ、１′＃：、は硝酸セリウムを含む溶液が用いられる
。定着液の場合には、通常、６０〜５０係の濃度のもの
が用いられるが、それ以外の濃度であってもよい。１だ
、硝酸セリウムでは、多くの喝今、６〜１２係の濃度で
用いられるが、それ以上のａ蜜でハ危険が伴すう。いす
ね、の、湯汁も濃度が低すきると液量を多く要するため
好ま（２〈ないｌＴ’ｌ：た、溶液の隠度は室部でもよ
いが、反応速度を高めるため成る程度高温にするのか好
１１〜く、多くの場合、約１！１０°Ｃに保ブ乞几る。In the method for separating silver from waste film according to the present invention, the waste film is immersed in a solution in order to ionize the silver contained in the waste film using M iQ'4 L. At this time, it is preferable to stir the inside of the tank in order to improve the contact between the waste film and the solution. The solution and I- should contain a drug capable of dissolving silver, preferably a solution containing sodium thiosulfate, a so-called fixing solution, and 1'#:, a solution containing cerium nitrate is used. used. In the case of a fixer, a fixer having a concentration of 60 to 50 is usually used, but other concentrations may be used. First, cerium nitrate is often used in concentrations of 6 to 12, but higher concentrations are dangerous. Hot water is also preferable because it requires a large amount of liquid if the concentration is low (2〈T'l: The temperature of the solution can be kept indoors, but it should be kept at a high temperature to increase the reaction rate. In most cases, the temperature should be kept at about 1~10°C.
なお、廃フィルムと１．てＩｄ通常の写真フィルムのほ
か映写フィルム、複写用マイクロフィルムなど、各種フ
ィルムの使用済のものが含まれる。In addition, waste film and 1. In addition to ordinary photographic film, this includes used films such as projection film and microfilm for copying.
Ｊ廃フィルムはそのままの形で前記浴液中ｖｃ、醍／Ｉ
］ｔしてもよいことは言うまでもないが、溶液との接触
を良好にするため、ｍ液中に入れる前１ｃ ＩＮ３フィ
ルムをなるべく細かく切断または破砕することが好ま１
−い。なお、切断または破砕後の廃フィルムは不揃いで
あってもよいが、ふるいにかけて均一にすることが好１
１．い。廃フィルムの訓片化１１クラッシャーまたは切
削機など、適当な装置で行なうことができる。このよう
に廃フィルムを細片化して比較的均一にすれば、大量の
廃フィルムを連続的に処理するのに適するものとなる。The J waste film was left as it was in the bath solution with VC and DM/I.
] It goes without saying that the IN3 film may be cut or crushed as finely as possible before being placed in the solution in order to improve contact with the solution.
- Yes. Note that the waste film after cutting or crushing may be irregular, but it is preferable to sieve it to make it uniform.
1. stomach. Cutting waste film into fragments 11 This can be carried out using any suitable equipment such as a crusher or a cutting machine. By breaking the waste film into pieces and making them relatively uniform in this way, it becomes suitable for continuously processing large amounts of waste film.
次いで、銀を溶解した溶液を濾過１〜、または他の方法
で銀溶解後の廃フィルム、即ちフィルムのベースである
ポリ、エステルとゼラチンを除去し、イオン化銀を含む
溶液から銀を分離する。Next, the silver-dissolved solution is filtered (1) or by other methods to remove the waste film after silver dissolution, that is, the polyester and gelatin that are the base of the film, to separate silver from the solution containing ionized silver.
溶液中に溶解した銀はイオン化１−た形で存在し、従っ
てそのような銀の分離ｄ電気分解、または金属置換、も
１−〈は化学反応凝集法でん法、などによって容易にな
される。電気分解で銀を分離する場合、例えば電極と（
−て陽極にカーボンを、且つ陰極にステンレスを用いる
ことによって電気分解が行なわれ、陰＋＄ＩＣ高純度の
銀が付着する。また、銀を溶液中１ｃ溶解するため廃フ
ィルムに含まれる全ての銀が、＠解され、且つ回収され
る。電気分解後の溶液は再使用が可能であり、公害を生
じることもない。−ｔた、仮に銀を回収後の溶液を使い
捨てにしても子ＩＬ来の１０の１程度ですむｎ’ｌ：た
、化学反応凝集法でん法の場合、イオン化銀を含む溶液
中に例えば塩酸を加えて塩化銀を析出させ、塩化銀の沈
でん物を分離して精練することによって銀が回収される
。々お、そのｊうな塩化銀は亜鉛等によって置換するこ
とにより、それから銀が得られる。Silver dissolved in solution exists in an ionized form, and therefore separation of such silver by electrolysis, or metal substitution, is easily accomplished by chemical reaction agglomeration methods, etc. . When separating silver by electrolysis, for example, an electrode (
Electrolysis is carried out by using carbon for the anode and stainless steel for the cathode, and high-purity silver is deposited on the anode. Moreover, since silver is dissolved in the solution, all the silver contained in the waste film is decomposed and recovered. The solution after electrolysis can be reused and does not cause pollution. In addition, even if the solution after recovering silver is disposable, it will only be about 1/10 of the amount of silver used in the production of silver.In the case of chemical reaction aggregation method, for example, in a solution containing ionized silver, Silver is recovered by adding hydrochloric acid to precipitate silver chloride, and separating and scouring the silver chloride precipitate. In addition, silver can be obtained from the silver chloride by replacing it with zinc or the like.
上記のように、本発明方法では、電気分解ｉたけ化学反
応によって銀を回収するたぬ高純度の銀が得られ、且つ
従来のようにポリエステルを除去１−た後にゼラチンに
含まれた銀を分離するという困難な工程を含まないので
、銀の分離が容易になされる。そ１−で、廃フィルムに
含まれる銀全完全に、即ちその全量を分離でき、従って
、銀の回収歩留を著１．〈向上することができる。その
上、公害の問題も生じることがない。As mentioned above, in the method of the present invention, high-purity silver can be obtained by recovering silver by an electrolytic chemical reaction, and silver contained in gelatin can be recovered after removing polyester as in the conventional method. Since it does not involve the difficult step of separating, silver can be easily separated. In method 1-, all the silver contained in the waste film can be completely separated, that is, the entire amount thereof, and therefore the recovery yield of silver can be significantly reduced. <It can be improved. Moreover, there will be no problem of pollution.
なお、廃フィルムのポリエステルは多くの場合、合成綿
等と１〜て再１吏用されるが、その場舒、ゼラチンを除
去することが不可欠である。銀を含むゼラチンをポリエ
ステルから分離することは困難な作業であり、作業性が
低ドするが、本発明のように、廃フィルムから先ず銀を
溶解して除去し、ポリエステルからゼラチンのみを除去
することけ苛性ソーダなどアルカリ薬品によって容易に
なされる。そのためポリエステルの再利用の点でも利点
がある。Incidentally, the polyester waste film is often reused with synthetic cotton or the like, but it is essential to remove the gelatin at the same time. Separating gelatin containing silver from polyester is a difficult task and has low workability, but as in the present invention, silver is first dissolved and removed from waste film and only gelatin is removed from polyester. This is easily done with alkaline chemicals such as caustic soda. Therefore, there is an advantage in terms of reusing polyester.
次に本発明の若干の実施例について述べる。Next, some embodiments of the present invention will be described.
実施例１
槽内に濃度ろ０％の定着液５［］ＪＩを入れ、その中に
通常の写真フィルムの廃フィルム２０ｋｇを浸漬１−１
且つ攪拌１−１１５分間が経過した後に、廃フィルムを
構内から引出した。その定着（夜をカーボンを陽極に且
つステンレスを陰極にして４．５ｖ。Example 1 Put 0% concentration filtration fixer 5[]JI in a tank and immerse 20 kg of ordinary photographic film waste in it 1-1.
And after 1-115 minutes of stirring had elapsed, the waste film was pulled out of the premises. Fixation (4.5V at night with carbon as the anode and stainless steel as the cathode).
Ｉ Ｑ［ｌＡの電流を６０分間通電して電気分解を行っ
た。その結果、陰ｉ［：２８０ｇの銀が付着したので、
それを回収した。Electrolysis was carried out by applying a current of IQ[lA for 60 minutes. As a result, 280 g of silver was attached, so
I retrieved it.
この上う［銀を回収（−だ後、銀を溶解した後の廃フィ
ルムを焼却して銀の残留分が在るかどうか調べたところ
、銀の灰分はなく、廃フイルム中の銀は全て溶解１−た
ことを確認１７た。また、電気分解後の溶質中に銀の存
在を調べたところ、ないことが解った。In addition, after recovering the silver, we incinerated the waste film after dissolving the silver and investigated whether there was any residual silver, and found that there was no silver ash, and all the silver in the waste film was It was confirmed that the solute was dissolved17.Also, when the presence of silver was investigated in the solute after electrolysis, it was found that there was no silver.
実施例２
槽内に濃度６％の硝酸セリウム溶液５０１金入れ、通常
の写真フィルムの廃フィルム２５ ｋｇをり１２、且つ
攪拌し、５分間が経過した後に、廃フィルムを槽内から
引出１．た。セの硝酸セリウム溶液に濃度６５％の塩酸
３３０００を加えて、塩化銀を析出させ、をらに塩化銀
の沈でんＩ吻を分離後、精練１．てろ５０３の尿を回収
１−だ。Example 2 A cerium nitrate solution with a concentration of 6% (501 gold) was placed in a tank, 25 kg of waste film from ordinary photographic film was placed in the tank, and after stirring for 5 minutes, the waste film was pulled out from the tank. Ta. Add 33,000 ml of hydrochloric acid with a concentration of 65% to the cerium nitrate solution to precipitate silver chloride, separate the silver chloride precipitate, and scouring 1. Collect urine from Tero 503 1-.
そのように銀を回収した後、実姉例１と同様にして、調
べたところ廃フイルム中の銀１１全て溶解したこと、お
よび銀回収後の溶液中に銀のないことが解った。After recovering the silver in this manner, it was investigated in the same manner as in Example 1, and it was found that all of the silver 11 in the waste film had been dissolved, and that there was no silver in the solution after silver recovery.
Claims (1)
まれる銀を溶解してイオン化する段階と、そのように溶
解されたイオン化銀を含む溶液から銀を分離する段階を
含む廃フィルムからの銀の分離方法。 （２、特許請求の範囲第１項に記載の銀の分離方法にお
いて、前記溶液は定着液である廃フィルムからの銀の分
離方法。 （３）、特許請求の範囲第１項に記載の銀の分離方法に
おいて、前記溶液は硝酸セリウムを含む溶液である廃フ
ィルムからの銀の分離方法。 （４）０％許請求の範囲第１項に記載の銀の分離方法に
おいて、前記イオン化銀は電気分解に上って分離される
廃フィルムからの銀の分離方法。 （５）、特許請求の範囲第１項に記載の銀の分離方法に
おいて、前記イオン化銀は金属置換法によって分離され
る廃フィルムからの銀の分離方法。 （６）、特許請求の範囲第１項に記載の銀の分離方法に
おいて、前記イオン化銀は化学反応疑集沈でん法によっ
て分離される廃フィルムからの銀の分離方法。 （力、特許請求の範囲第１項に記載の銀の分離方法にお
いて、前記銀の溶解段階の前に廃フイルムヲ破断する段
階を含む廃フィルムからの銀の分離方法。[Claims] (1) A step of immersing the waste film in a solution to dissolve and ionize the silver contained in the waste film, and separating the silver from the solution containing the dissolved ionized silver. A method for separating silver from waste film including steps. (2. A method for separating silver from a waste film, in which the solution is a fixing solution. (3) A method for separating silver from a waste film, in which the solution is a fixing solution. In the method for separating silver from a waste film, the solution is a solution containing cerium nitrate. (4) 0% tolerance In the method for separating silver according to claim 1, the ionized silver is A method for separating silver from a waste film separated by decomposition. (5) In the method for separating silver according to claim 1, the ionized silver is separated from a waste film by a metal substitution method. (6) A method for separating silver from a waste film according to claim 1, wherein the ionized silver is separated by a chemical reaction combined precipitation method. (A method for separating silver from a waste film as claimed in claim 1, including the step of breaking the waste film before the step of dissolving the silver.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17240482A JPS5964721A (en) | 1982-09-30 | 1982-09-30 | Separation of silver from waste film |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17240482A JPS5964721A (en) | 1982-09-30 | 1982-09-30 | Separation of silver from waste film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS5964721A true JPS5964721A (en) | 1984-04-12 |
Family
ID=15941316
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17240482A Pending JPS5964721A (en) | 1982-09-30 | 1982-09-30 | Separation of silver from waste film |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5964721A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0635154A (en) * | 1992-05-08 | 1994-02-10 | Ind Technol Res Inst | Photographic film and method of recovering silver from photographic developing waste fluid |
| JP2009185389A (en) * | 2009-05-11 | 2009-08-20 | Hitachi Zosen Corp | Recycling method for valuable metal |
-
1982
- 1982-09-30 JP JP17240482A patent/JPS5964721A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0635154A (en) * | 1992-05-08 | 1994-02-10 | Ind Technol Res Inst | Photographic film and method of recovering silver from photographic developing waste fluid |
| JP2009185389A (en) * | 2009-05-11 | 2009-08-20 | Hitachi Zosen Corp | Recycling method for valuable metal |
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