CN1151033A - Method for recovering silver from solid-phase photosensitive material - Google Patents
Method for recovering silver from solid-phase photosensitive material Download PDFInfo
- Publication number
- CN1151033A CN1151033A CN95119806A CN95119806A CN1151033A CN 1151033 A CN1151033 A CN 1151033A CN 95119806 A CN95119806 A CN 95119806A CN 95119806 A CN95119806 A CN 95119806A CN 1151033 A CN1151033 A CN 1151033A
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- CN
- China
- Prior art keywords
- silver
- enzyme
- solid
- sodium carbonate
- mud
- 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
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- 229910052709 silver Inorganic materials 0.000 title claims abstract description 87
- 239000004332 silver Substances 0.000 title claims abstract description 87
- 239000000463 material Substances 0.000 title claims abstract description 24
- 238000000034 method Methods 0.000 title claims abstract description 18
- 239000007790 solid phase Substances 0.000 title claims abstract description 14
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims abstract description 86
- 239000000839 emulsion Substances 0.000 claims abstract description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 14
- 238000003723 Smelting Methods 0.000 claims abstract description 9
- 108091005804 Peptidases Proteins 0.000 claims abstract description 4
- 239000004365 Protease Substances 0.000 claims abstract description 3
- 102100037486 Reverse transcriptase/ribonuclease H Human genes 0.000 claims abstract description 3
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 30
- 102000004190 Enzymes Human genes 0.000 claims description 26
- 108090000790 Enzymes Proteins 0.000 claims description 26
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 15
- 238000002386 leaching Methods 0.000 claims description 14
- 230000007935 neutral effect Effects 0.000 claims description 11
- ADZWSOLPGZMUMY-UHFFFAOYSA-M silver bromide Chemical compound [Ag]Br ADZWSOLPGZMUMY-UHFFFAOYSA-M 0.000 claims description 11
- 230000004907 flux Effects 0.000 claims description 9
- 239000002893 slag Substances 0.000 claims description 9
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 8
- 230000000694 effects Effects 0.000 claims description 8
- 229910021538 borax Inorganic materials 0.000 claims description 7
- ZCCIPPOKBCJFDN-UHFFFAOYSA-N calcium nitrate Chemical compound [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ZCCIPPOKBCJFDN-UHFFFAOYSA-N 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 7
- 235000010333 potassium nitrate Nutrition 0.000 claims description 7
- FGIUAXJPYTZDNR-UHFFFAOYSA-N potassium nitrate Inorganic materials [K+].[O-][N+]([O-])=O FGIUAXJPYTZDNR-UHFFFAOYSA-N 0.000 claims description 7
- 239000004328 sodium tetraborate Substances 0.000 claims description 7
- 235000010339 sodium tetraborate Nutrition 0.000 claims description 7
- JHJLBTNAGRQEKS-UHFFFAOYSA-M sodium bromide Chemical compound [Na+].[Br-] JHJLBTNAGRQEKS-UHFFFAOYSA-M 0.000 claims description 6
- 239000007787 solid Substances 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 4
- 239000000758 substrate Substances 0.000 claims description 4
- 238000000227 grinding Methods 0.000 claims description 3
- 241001062472 Stokellia anisodon Species 0.000 claims description 2
- 230000001376 precipitating effect Effects 0.000 claims description 2
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims 6
- 238000002791 soaking Methods 0.000 claims 1
- 238000001354 calcination Methods 0.000 abstract 1
- 239000002699 waste material Substances 0.000 description 10
- 239000002585 base Substances 0.000 description 6
- 239000000203 mixture Substances 0.000 description 4
- 238000011084 recovery Methods 0.000 description 4
- 239000003153 chemical reaction reagent Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 108090000145 Bacillolysin Proteins 0.000 description 2
- 108091005507 Neutral proteases Proteins 0.000 description 2
- 102000035092 Neutral proteases Human genes 0.000 description 2
- 239000012141 concentrate Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000004062 sedimentation Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 239000006228 supernatant Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- 239000002351 wastewater Substances 0.000 description 2
- 108091005658 Basic proteases Proteins 0.000 description 1
- 102000035195 Peptidases Human genes 0.000 description 1
- 206010034972 Photosensitivity reaction Diseases 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000002306 biochemical method Methods 0.000 description 1
- 239000000919 ceramic Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 238000010828 elution Methods 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 238000010907 mechanical stirring Methods 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 229910000510 noble metal Inorganic materials 0.000 description 1
- 230000036211 photosensitivity Effects 0.000 description 1
- 239000010970 precious metal Substances 0.000 description 1
- 239000010734 process oil Substances 0.000 description 1
- 235000019833 protease Nutrition 0.000 description 1
- 235000019419 proteases Nutrition 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 150000003839 salts Chemical class 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000003756 stirring Methods 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
- Y02P10/20—Recycling
Landscapes
- Manufacture And Refinement Of Metals (AREA)
Abstract
A process for recovering silver from solid-phase photosensitive material includes such steps as dissolving the silver emulsion layer in protease, settling, separating silver mud, calcining silver mud, immersing the dregs in water, and smelting. The purity of the silver is 99.9-99.99%, and the direct yield is 97-99.7%.
Description
A method for recovering silver from a solid-phase photosensitive material. The present invention relates to precious metal metallurgy.
Silver is a noble metal, and is widely used for manufacturing photographic photosensitive materials due to the strong photosensitivity of its compound, silver bromide, and about 40% of the world's silver yield is used for photosensitive materials. A large amount of waste materials are generated in the production and use processes of the photosensitive materials, and the silver is recovered from the waste photosensitive materials and becomes a precious secondary silver resource. The solid-phase photosensitive material includes: waste films (motion picture films, various black and white color films, X-ray films), waste photographic papers, lithographic films, etc., contain about 0.2-5% silver. There are 3 types of methods for recovering silver from such waste photosensitive materials: (1) the burning method is that the solid-phase photosensitive material is burned at the temperature of over 400 ℃, the film base is burned off, silver-containing ash is left, and the silver is recovered by smelting or wet method. The main disadvantages are that burning off the substrate is both wasteful and environmentally polluting. (2) The chemical method is that acid, alkali, salt, etc. are used to dissolve silver layer on the film to obtain silver mud, and the silver mud is further treated to obtain silver. The most chemical method is used, which can keep the film base, but some reagents are corrosive to the equipment, the waste liquid pollutes the environment, (3) the biochemical method, such as US3748123, adopts protease to process the film, so that the silver-containing emulsion layer is reacted with enzyme to separate from the film base, the silver-containing emulsion solution is processed to obtain silver mud, and the silver mud is separated and then processed to obtain metallic silver.
The invention aims to find out proper conditions for biochemical treatment of waste solid photosensitive materials generated in factories to recycle silver and film substrates, and further research out a better scheme for separating and recycling silver into metallic silver.
The method for recovering silver from solid-phase photosensitive material includes dissolving silver emulsion layer with proteinase, settling, separating silver mud, roasting silver mud, leaching the roasted residue with water, smelting the leached residue to obtain metal silverSeveral steps. The specific method comprises (1) cutting the solid phase photosensitive material, and eluting the silver-containing emulsion layer with neutral enzyme (5 ten thousand activity units) or alkaline enzyme (8 ten thousand activity units) solution under the following conditions: enzyme type concentration (g/L) temperature (DEG C) PH value liquid (volume, L):solid (weight, Kg) neutral enzyme 0.01-1.033-48-63-12: 1 alkaline enzyme 0.02-1.050-609-: neutral enzyme 0.01-1.040-45-64-10: 1 alkaline enzyme 0.05-1.050-609-113-5: 1, mechanically stirring, and taking out the substrate after the silver emulsion layer is dissolved. (2) Adjusting pH of the emulsion solution with dilute sulfuric acid, adjusting pH of neutral enzyme silver removing solution to 1.2-4.5, preferably pH to 1.2-2.5, and adjusting pH of alkaline enzyme silver removing solution to 2-5, preferably pH to 2-3.5, precipitating silver mud (AgBr as main component), filtering and separating silver mud. (3) Drying the silver mud, grinding, adding sodium carbonate according to the molar ratio of the silver bromide to the sodium carbonate (1: 1-2.2), roasting at the temperature of 550-700 ℃ for 1-3 hours to convert the silver bromide into silver, wherein the reaction is as follows: preferably sodium carbonate, the ratio of the silver bromide content to the sodium carbonate content (molar ratio) is 1: 1-1.5, roasting for 2-3 hours at the temperature of 650-,it is preferable thatIt is leached with hot water at 80 deg.c to dissolve the sodium bromide produced in the reaction, and the solution contains silver less than 0.000Xg/l and is discarded.
(4) After the roasted water leached slag is dried, flux (sodium carbonate + borax + saltpeter) is added to smelt, and the proportion of the flux is that the weight ratio of sodium carbonate to borax to saltpeter is 30-10: 10-3: 1, and the weight ratio of the flux is 11-10: 6-5: 1, and the pure silver is obtained after smelting for more than 0.5h at the temperature of 1000-1100 ℃, and the best 1050-1100 ℃. The purity of the silver is 99.9-99.99%, the direct recovery rate is 97-99.7%, and the total recovery rate is-100%.
The invention has the advantages that: 1. can recover silver and base material at the same time, the silver purity is high, 99.99%, the recovery rate is high, more than 99%, 2, the method condition is easy to master and operate, the reagent is the ordinary reagent, the apparatus is also a general apparatus. 3. The solid-phase photosensitive material can be used for hard-to-process oil color positive sheets or waste liquor concentrate with complex composition and low silver content. 4. The waste water contains low silver, does not corrode equipment and does not pollute the environment.
Examples
Example 1, waste X-ray film was shredded and analyzed for silver content by stripping, sedimentation and analysis of the supernatant using neutral protease (5 ten thousand activity units) or alkaline protease (8 ten thousand activity units) at 2.613% silver content as follows: enzyme type concentration (g/L) temperature (deg.C) liquid (volume, L) to elution sedimentation supernatant
Solid (Kg) pH value Agg/L neutral enzyme 0.01-1.040-454: 1-61.5-2.5<0.0038 alkaline enzyme 0.05-1.050-603: 19-112-3.5<0.0008
Example 2, waste X-ray film, 9260g, contained 2.613% silver in an amount of 241.98g, cut into pieces of about 6X 8 cm.
(1) Neutral protease 0.5g/l solution, temperature 33-43 deg.C, pH 6, in liquid (volume, l) to solid (weight, Kg) 10: 1The method comprises the following steps of (1) dissolving and removing a silver-containing emulsion layer, fishing out a film base, (2) adjusting the pH value of a solution to be 1.5 by using dilute sulfuric acid, settling silver mud (mainly AgBr), separating the silver mud, analyzing the silver content, wherein the silver content of the solution accounts for 0.0058 percent of the total silver content, the silver mud accounts for 99.95 percent, and the film base accounts for 0.047 percent, and (3) drying the silver mud according to the AgBr content and Na content2CO3Mixing silver mud and sodium carbonate uniformly at a molar ratio of 1: 1, placing the mixture into a ceramic evaporation vessel, roasting the mixture for 3 hours at the temperature of 700 ℃, cooling the mixture, leaching NaBr by using hot water at the temperature of 85-90 ℃ through mechanical stirring, filtering and washing the filtered solution, wherein water leaching residues are crude sponge silver, and roasting-leaching results are as follows: leaching residue contains 99.99% silver, leaching liquid contains 0.0098%, baking roasting-water leaching residue, adding flux (sodium carbonate + borax + saltpeter) in the weight ratio of 100: 33 to 10.3: 5.2: 1, smelting at 1050 deg.C, holding constant temperature for 0.5 hr to obtain 241.303g of pure silver with purity of 99.99%, 99.78% of metal silver and 0.22% of residue silver. The direct silver yield was 99.72% from film.
Example 3
10102g of color positive plate, containing 2.98% of Ag2 and 301.44g of silver, was cut into strips of about 10X 3.5cm, and treated by the same procedures and conditions as in example 2 to obtain 295g of metallic silver, with a purity of 99.9%, a straight yield of 97.57%, a slag silver content of 2.13%, and a total recovery of-100%.
Example 4
3445g of silver mud containing silver concentrate, 22.86% of Ags and 787.53g of silver content in coating and washing wastewater of a photosensitive material factory, 773.2g of metal with the purity of 99.95% and the direct yield of 98.16% after treatment by the steps (3) and (4) of the treatment example 2, and the silver content in slag accounts for 1%.
Claims (2)
1. The method for recovering silver from the solid-phase photosensitive material comprises the steps of dissolving a silver emulsion layer by using protease, settling and separating silver mud, roasting the silver mud, soaking roasting slag in water, and smelting the water leaching slag to obtain metallic silver, and is characterized in that:
1.1 chopping the solid phase photosensitive material, and leaching the silver-containing emulsion layer with a neutral enzyme (5 ten thousand activity units) or an alkaline enzyme (8 ten thousand activity units) solution under the following conditions: pH value liquid (volume, L) and solid (weight, Kg) neutral enzyme 0.01-1.033-48-63-12: 1 alkaline enzyme 0.02-1.050-609-114-,
1.2 adjusting the pH value of the desilvering emulsion solution obtained by 1.1 by using dilute sulfuric acid, settling silver mud (mainly AgBr), filtering and separating, wherein the pH value of a neutral enzyme desilvering solution is 1.2-4.5, and the pH value of an alkaline enzyme desilvering solution is 2-5,
1.3 drying the silver mud obtained in 1.2, grinding, adding sodium carbonate or sodium hydroxide according to the molar ratio of silver bromide to sodium carbonate (or sodium hydroxide) of 1: 1-2.2, roasting for 1-3 hours at 550-700 ℃, leaching the roasted slag with hot water, preferably hot water at about 80 ℃, separating and removing the leachate,
1.4 after baking the water leaching slag obtained in 1.3, adding flux (sodium carbonate + borax + saltpeter) for smelting, wherein the weight ratio of the materials to the flux is 100: 40-20, the weight ratio of the sodium carbonate to the borax to the saltpeter is 30-10: 10-3: 1, smelting at the temperature of 1000 ℃ and 1100 ℃, and keeping the temperature for more than 0.5h to obtain the pure silver.
2. The method of recovering silver from a solid-phase photosensitive material of claim 1, wherein:
2.1 stripping the silver-containing emulsion layer with neutral enzyme (5 ten thousand activity units) or alkaline enzyme (8 ten thousand activity units) under the following conditions: the pH value liquid (volume, L) and solid (weight, Kg) neutral enzyme with the enzyme type concentration (g/L) temperature (DEG C) are 0.01-1.040-45-64-10: 1 alkaline enzyme 0.05-1.050-609-113-5: 1 solid phase photosensitive material, the solid phase photosensitive material is cut up, mechanically stirred, the substrate is fished out after the silver emulsion layer is dissolved and removed,
2.2 adjusting pH of the emulsion solution with dilute sulfuric acid to 2.1, precipitating silver mud (AgBr as main component) with neutral enzyme (pH 1.5-2.5) and alkaline enzyme (pH 2-3.5), filtering,
2.3 drying the silver mud (the main component is AgBr) obtained in 2.2, grinding, adding sodium carbonate, roasting for 2-3 hours at the temperature of 650 ℃ and 700 ℃, leaching sodium bromide from the roasted slag by hot water at the temperature of-80 ℃, separating the leaching solution,
2.4 baking the roasted water leaching slag obtained in 2.3, adding flux (sodium carbonate + borax + saltpeter) to smelt, wherein the ratio of the flux to the material is 100: 30-20, the weight ratio of the flux to the sodium carbonate to the borax to the saltpeter is 11-10: 6-5: 1, and smelting for about 0.5 hour at 1050-1100 ℃ to obtain the pure silver.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95119806A CN1054214C (en) | 1995-11-20 | 1995-11-20 | Method for recovering silver from solid-phase photosensitive material |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95119806A CN1054214C (en) | 1995-11-20 | 1995-11-20 | Method for recovering silver from solid-phase photosensitive material |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1151033A true CN1151033A (en) | 1997-06-04 |
| CN1054214C CN1054214C (en) | 2000-07-05 |
Family
ID=5082172
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95119806A Expired - Fee Related CN1054214C (en) | 1995-11-20 | 1995-11-20 | Method for recovering silver from solid-phase photosensitive material |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1054214C (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102732733A (en) * | 2012-05-31 | 2012-10-17 | 巴彦淖尔紫金有色金属有限公司 | Process for recovering silver and lead sulfate from slag |
| CN106125498A (en) * | 2016-08-27 | 2016-11-16 | 盛隆资源再生（无锡）有限公司 | A kind of waste photographic film reclaims the method for silver and chip base |
| CN106244815A (en) * | 2016-08-31 | 2016-12-21 | 无锡中天固废处置有限公司 | A kind of method separating and recovering silver from photographic film |
| CN108796221A (en) * | 2017-05-02 | 2018-11-13 | 广州合凯环保科技有限公司 | A kind of silver mud method of smelting |
| CN109266855A (en) * | 2018-06-18 | 2019-01-25 | 曹大平 | The non-cyanogen of non-ferrous metal rare precious metal extracts waste water complete alternation technique |
| CN110466090A (en) * | 2019-09-10 | 2019-11-19 | 珠海市安能环保科技有限公司 | A method of recycling silver and PET film from HW16 waste photographic film |
-
1995
- 1995-11-20 CN CN95119806A patent/CN1054214C/en not_active Expired - Fee Related
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102732733A (en) * | 2012-05-31 | 2012-10-17 | 巴彦淖尔紫金有色金属有限公司 | Process for recovering silver and lead sulfate from slag |
| CN102732733B (en) * | 2012-05-31 | 2015-05-20 | 巴彦淖尔紫金有色金属有限公司 | Process for recovering silver and lead sulfate from slag |
| CN106125498A (en) * | 2016-08-27 | 2016-11-16 | 盛隆资源再生（无锡）有限公司 | A kind of waste photographic film reclaims the method for silver and chip base |
| CN106244815A (en) * | 2016-08-31 | 2016-12-21 | 无锡中天固废处置有限公司 | A kind of method separating and recovering silver from photographic film |
| CN108796221A (en) * | 2017-05-02 | 2018-11-13 | 广州合凯环保科技有限公司 | A kind of silver mud method of smelting |
| CN109266855A (en) * | 2018-06-18 | 2019-01-25 | 曹大平 | The non-cyanogen of non-ferrous metal rare precious metal extracts waste water complete alternation technique |
| CN110466090A (en) * | 2019-09-10 | 2019-11-19 | 珠海市安能环保科技有限公司 | A method of recycling silver and PET film from HW16 waste photographic film |
| CN110466090B (en) * | 2019-09-10 | 2021-03-30 | 珠海市安能环保科技有限公司 | Method for recovering silver and PET (polyethylene terephthalate) film from HW16 waste photosensitive film |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1054214C (en) | 2000-07-05 |
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