ITPD970236A1 - PROCEDURE FOR THE ELIMINATION OF METAL SOULS IN COPPER ALUMINUM IRON OR THEIR ALLOYS IN THE PRODUCTION OF CABLE OBJECTS IN PRECIOUS METALS SUCH AS GOLD PLATINUM SILVER AND THEIR ALLOYS. - Google Patents
PROCEDURE FOR THE ELIMINATION OF METAL SOULS IN COPPER ALUMINUM IRON OR THEIR ALLOYS IN THE PRODUCTION OF CABLE OBJECTS IN PRECIOUS METALS SUCH AS GOLD PLATINUM SILVER AND THEIR ALLOYS. Download PDFInfo
- Publication number
- ITPD970236A1 ITPD970236A1 IT000236A ITPD970236A ITPD970236A1 IT PD970236 A1 ITPD970236 A1 IT PD970236A1 IT 000236 A IT000236 A IT 000236A IT PD970236 A ITPD970236 A IT PD970236A IT PD970236 A1 ITPD970236 A1 IT PD970236A1
- Authority
- IT
- Italy
- Prior art keywords
- alloys
- metal
- cores
- elimination
- solution
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 33
- 239000000956 alloy Substances 0.000 title claims description 17
- 229910045601 alloy Inorganic materials 0.000 title claims description 17
- 238000003379 elimination reaction Methods 0.000 title claims description 14
- 230000008030 elimination Effects 0.000 title claims description 13
- 239000010970 precious metal Substances 0.000 title claims description 12
- 238000004519 manufacturing process Methods 0.000 title claims description 7
- -1 COPPER ALUMINUM IRON Chemical compound 0.000 title 1
- GDYSGADCPFFZJM-UHFFFAOYSA-N [Ag].[Pt].[Au] Chemical compound [Ag].[Pt].[Au] GDYSGADCPFFZJM-UHFFFAOYSA-N 0.000 title 1
- XTHPWXDJESJLNJ-UHFFFAOYSA-M chlorosulfate Chemical compound [O-]S(Cl)(=O)=O XTHPWXDJESJLNJ-UHFFFAOYSA-M 0.000 claims description 22
- 229910052751 metal Inorganic materials 0.000 claims description 18
- 239000002184 metal Substances 0.000 claims description 18
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 17
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 claims description 12
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 10
- 229910052802 copper Inorganic materials 0.000 claims description 10
- 239000010949 copper Substances 0.000 claims description 10
- 229910052782 aluminium Inorganic materials 0.000 claims description 9
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 9
- 229910052742 iron Inorganic materials 0.000 claims description 8
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 claims description 6
- 229910052737 gold Inorganic materials 0.000 claims description 6
- 239000010931 gold Substances 0.000 claims description 6
- 229910052500 inorganic mineral Inorganic materials 0.000 claims description 6
- 239000011707 mineral Substances 0.000 claims description 6
- 229910052697 platinum Inorganic materials 0.000 claims description 6
- 229910052709 silver Inorganic materials 0.000 claims description 6
- 239000004332 silver Substances 0.000 claims description 6
- BQCADISMDOOEFD-UHFFFAOYSA-N Silver Chemical compound [Ag] BQCADISMDOOEFD-UHFFFAOYSA-N 0.000 claims description 5
- YDZQQRWRVYGNER-UHFFFAOYSA-N iron;titanium;trihydrate Chemical compound O.O.O.[Ti].[Fe] YDZQQRWRVYGNER-UHFFFAOYSA-N 0.000 claims description 2
- 239000007788 liquid Substances 0.000 claims description 2
- 239000000203 mixture Substances 0.000 claims description 2
- 238000000926 separation method Methods 0.000 claims description 2
- 238000007654 immersion Methods 0.000 claims 1
- 239000000047 product Substances 0.000 description 5
- 235000010755 mineral Nutrition 0.000 description 4
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 description 3
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 150000003839 salts Chemical class 0.000 description 3
- 239000002699 waste material Substances 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000010953 base metal Substances 0.000 description 2
- 150000001805 chlorine compounds Chemical class 0.000 description 2
- 238000001914 filtration Methods 0.000 description 2
- 239000003517 fume Substances 0.000 description 2
- 238000000746 purification Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229910021578 Iron(III) chloride Inorganic materials 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- AZDRQVAHHNSJOQ-UHFFFAOYSA-N alumane Chemical group [AlH3] AZDRQVAHHNSJOQ-UHFFFAOYSA-N 0.000 description 1
- 235000011114 ammonium hydroxide Nutrition 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000013065 commercial product Substances 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000009472 formulation Methods 0.000 description 1
- 229910001385 heavy metal Inorganic materials 0.000 description 1
- RBTARNINKXHZNM-UHFFFAOYSA-K iron trichloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- 229910000359 iron(II) sulfate Inorganic materials 0.000 description 1
- 150000002739 metals Chemical class 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 1
- 231100000331 toxic Toxicity 0.000 description 1
- 230000002588 toxic effect Effects 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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- Conductive Materials (AREA)
- Adornments (AREA)
Description
DESCRIZIONE DESCRIPTION
La presente invenzione si riferisce ad un procedimento per l'eliminazione di anime metalliche in rame, alluminio, ferro o loro leghe, nella produzione di oggetti cavi in metalli preziosi quali oro, argento, platino e loro leghe. The present invention relates to a process for the elimination of metal cores made of copper, aluminum, iron or their alloys, in the production of hollow objects in precious metals such as gold, silver, platinum and their alloys.
Nel settore orafo è noto produrre oggetti cavi in metalli preziosi, quali oro o sue leghe, come ad esempio la canne vuote ed i fili vuoti, depositando o modellando il metallo prezioso su anime realizzate con metalli più vili che sono successivamente eliminate mediante un processo cosiddetto dì "vuotatura". Le anime normalmente utilizzate per la produzione di oggetti cavi d'oreficeria sono di rame, alluminio, ferro o loro leghe. In the goldsmith sector it is known to produce hollow objects in precious metals, such as gold or its alloys, such as empty rods and empty wires, by depositing or modeling the precious metal on cores made with more base metals which are subsequently eliminated by a so-called process say "emptying". The cores normally used for the production of hollow goldsmith objects are made of copper, aluminum, iron or their alloys.
I procedimenti noti di eliminazione delle anime in rame e sue leghe prevedono l'impiego di acido nitrico ovvero di soluzioni ammoniacali o di acido solforico. Per l'eliminazione di anime in ferro è invece noto utilizzare soluzioni di acido cloridrico mentre per le anime in alluminio è normalmente impiegata la soda caustica. The known processes for eliminating cores in copper and its alloys provide for the use of nitric acid or ammonia solutions or sulfuric acid. For the elimination of iron cores it is known to use hydrochloric acid solutions while caustic soda is normally used for aluminum cores.
I suddetti procedimenti noti presentano un principale inconveniente nel fatto che le sostanze utilizzate sono altamente inquinanti in termini di impatto ambientale e nocività per l'uomo, con il conseguente problema dello smaltimento delle scorie risultanti dalla eliminazione delle anime. Inoltre, i fumi sviluppati durante tali procedimenti, a seguito dell'impiego delle soluzioni acide anzidette, richiedono la predisposizione di adeguate attrezzature di trattamento con conseguenti costi in termini di impianti dì filtraggio e depurazione dell'aria. The aforementioned known processes have a main drawback in that the substances used are highly polluting in terms of environmental impact and harmfulness to humans, with the consequent problem of disposal of the waste resulting from the elimination of the cores. Furthermore, the fumes developed during these processes, following the use of the aforementioned acid solutions, require the provision of adequate treatment equipment with consequent costs in terms of air filtration and purification systems.
Inoltre, poiché i prodotti e le soluzioni acide utilizzate per l'eliminazione delle anime sono nocivi e tossici per l'uomo, essi devono essere conservati e manipolati con cura, richiedendo l'adozione di rigorose norme di sicurezza ed anti-infortunistiche. Furthermore, since the products and acid solutions used for the elimination of cores are harmful and toxic to humans, they must be stored and handled with care, requiring the adoption of rigorous safety and accident prevention regulations.
Scopo della presente invenzione è quello di superare gli inconvenienti lamentati con riferimento alla tecnica nota mediante un procedimento per l'eliminazione delle anime in rame, alluminio, ferro o loro leghe, che riduca in maniera sensibile i problemi di inquinamento ambientale e nocività per l'uomo associati alla produzione di oggetti cavi in metalli preziosi. The purpose of the present invention is to overcome the drawbacks complained of with reference to the known art by means of a process for the elimination of the cores made of copper, aluminum, iron or their alloys, which significantly reduces the problems of environmental pollution and harmfulness for the man associated with the production of hollow objects in precious metals.
Un altro scopo della presente invenzione è quello di ridurre o eliminare i costi derivanti dalla necessità di predisporre attrezzature ed impianti ausiliari per la depurazione ed il trattamento di sostanze e scorie inquinanti e pericolose. Another object of the present invention is to reduce or eliminate the costs deriving from the need to provide auxiliary equipment and systems for the purification and treatment of polluting and dangerous substances and waste.
Al fine di raggiungere gli scopi sopra indicati, la presente invenzione ha per oggetto un procedimento per l'eliminazione di anime in rame, alluminio, ferro o loro leghe le cui caratteristiche sono indicate nelle rivendicazioni da 1 a 6 che seguono . In order to achieve the purposes indicated above, the present invention relates to a process for the elimination of cores made of copper, aluminum, iron or their alloys, the characteristics of which are indicated in the following claims 1 to 6.
Inoltre la presente invenzione ha per oggetto l'uso di una soluzione di clorosolfato ferrico nel settore della produzione di oggetti cavi in metalli preziosi, quali oro, argento, platino e loro leghe, per la eliminazione di anime in rame, alluminio, ferro o loro leghe, le cui caratteristiche sono indicate nella rivendicazione 7. Furthermore, the present invention relates to the use of a solution of ferric chlorosulfate in the sector of the production of hollow objects in precious metals, such as gold, silver, platinum and their alloys, for the elimination of cores in copper, aluminum, iron or their alloys, the characteristics of which are indicated in claim 7.
Un vantaggio del procedimento secondo la presente invenzione risiede nel fatto che durante l'eliminazione delle anime metalliche non sono generati fumi o vapori nocivi, eliminando così la necessità di prevedere sistemi aspiranti o di filtraggio. An advantage of the process according to the present invention lies in the fact that during the elimination of the metal cores no harmful fumes or vapors are generated, thus eliminating the need to provide suction or filtering systems.
Un altro vantaggio consiste nel ridotto costo commerciale del prodotto con il quale è realizzata la soluzione di clorosolfato ferrico utilizzata nel procedimento di eliminazione delle anime metalliche della presente invenzione . Another advantage consists in the reduced commercial cost of the product with which the ferric chlorosulfate solution used in the metal core elimination process of the present invention is made.
Un altro importante vantaggio è che il prodotto commerciale anzidetto contiene bassi quantitativi di metalli pesanti inquinanti, se comparato alle forniture commerciali di cloruri e solfati ferrici impiegati nei procedimenti noti di eliminazione di anime metalliche. Another important advantage is that the aforementioned commercial product contains low quantities of polluting heavy metals, if compared to the commercial supplies of ferric chlorides and sulphates used in known processes for eliminating metal cores.
Un altro vantaggio consiste nel fatto che, in una forma preferita di attuazione del procedimento dell'invenzione, la soluzione di clorosolfato ferrico ed il metallo dell'anima in essa disciolto possono essere ulteriormente separati mediante un processo che non sviluppa prodotti gassosi, con il conseguente aumento di efficienza nella riutilizzazione dei componenti ed il risparmio nella realizzazione dell'impiantistica. Another advantage consists in the fact that, in a preferred embodiment of the process of the invention, the ferric chlorosulfate solution and the metal of the core dissolved in it can be further separated by a process that does not produce gaseous products, with the consequent increase in efficiency in the reuse of components and savings in plant construction.
Ulteriori caratteristiche e vantaggi risulteranno dalla descrizione dettagliata che segue di un esempio preferito, ma non limitativo, di attuazione della presente invenzione. Further characteristics and advantages will emerge from the following detailed description of a preferred, but not limiting, example of embodiment of the present invention.
Il procedimento secondo l'invenzione prevede la preparazione in una vasca di un bagno contenente una soluzione di clorosolfato ferrico (FeClSC>4), in sigla CSF. La concentrazione del clorosolfato ferrico è scelta di valore compreso tra il 10% ed il 40% in peso. Un valore preferito di tale concentrazione è pari al 20% in peso. The process according to the invention provides for the preparation in a tank of a bath containing a solution of ferric chlorosulfate (FeClSC> 4), in the abbreviation CSF. The concentration of the ferric chlorosulfate is chosen from a value between 10% and 40% by weight. A preferred value of this concentration is equal to 20% by weight.
La soluzione di clorosolfato ferrico così ottenuta viene riscaldata e mantenuta ad una temperatura non inferiore a 100°C, e preferibilmente di 105°C, per l'intera durata del procedimento . The ferric chlorosulfate solution thus obtained is heated and maintained at a temperature not lower than 100 ° C, and preferably 105 ° C, for the entire duration of the process.
Oggetti costituiti da anime ricoperte di oro, argento, platino e altri metalli preziosi, in particolare anime metalliche in rame, alluminio, ferro o loro leghe, vengono immersi nella vasca, in modo tale che dette anime metalliche vengano attaccate dal clorosolfato ferrico e vengano disciolte nella soluzione anzidetta. Il tempo di eliminazione delle anime varia a seconda della forma, consistenza e tecnica di applicazione del metallo prezioso. Al termine del trattamento nella soluzione di clorosolfato ferrico, gli oggetti in metallo prezioso vengono controllati mediante pesatura al fine di verificare che il metallo vile delle anime sia stato eliminato totalmente. Objects consisting of cores covered with gold, silver, platinum and other precious metals, in particular metal cores made of copper, aluminum, iron or their alloys, are immersed in the tank, in such a way that said metal cores are attacked by the ferric chlorosulfate and are dissolved in the aforementioned solution. The removal time of the cores varies according to the shape, consistency and technique of application of the precious metal. At the end of the treatment in the ferric chlorosulfate solution, the precious metal objects are checked by weighing in order to verify that the base metal of the cores has been totally eliminated.
Si fa notare che il clorosolfato ferrico impiegato nel procedimento di questa invenzione è di origine minerale ed in particolare proviene da FeS04~7H20 derivato da ilmenite naturale. A differenza quindi di altri prodotti, quali i sali ferrici utilizzati nei procedimenti noti e normalmente derivati da sottoprodotti dell'industria metallurgica, il clorosolfato ferrico, per la sua origine minerale, presenta ridottissimi quantitativi di metalli pesanti, nocivi ed altamente inquinanti. It should be noted that the ferric chlorosulfate used in the process of this invention is of mineral origin and in particular comes from FeS04 ~ 7H20 derived from natural ilmenite. Therefore, unlike other products, such as ferric salts used in known processes and normally derived from by-products of the metallurgical industry, ferric chlorosulfate, due to its mineral origin, has very small quantities of heavy, harmful and highly polluting metals.
Il clorosolfato ferrico di origine minerale ha inoltre un basso costo commerciale se comparato con altri prodotti, quali i sali ferrici impiegati nei procedimenti noti. Furthermore, ferric chlorosulfate of mineral origin has a low commercial cost if compared with other products, such as ferric salts used in known processes.
Inoltre, la soluzione esaurita a seguito della eliminazione delle anime metalliche può essere successivamente sottoposta ad un processo di separazione del clorosolfato ferrico così da rigenerare quest'ultimo per essere nuovamente impiegabile nel procedimento dell'invenzione. Furthermore, the exhausted solution following the elimination of the metal cores can be subsequently subjected to a process of separation of the ferric chlorosulfate so as to regenerate the latter to be usable again in the process of the invention.
Si fa notare altresì che l'impiego di clorosolfato ferrico di origine minerale comporta un contenuto assai ridotto di cloruri nel liquido residuo del procedimento, se comparato con quello ottenuto a partire dalle formulazioni di sali ferrici dei procedimenti noti. Ciò rende il trattamento dei residui di scarico più agevole e compatibile con i limiti imposti per legge. Ad esempio, il clorosolfato ferrico comporta un residuo di cloruri inferiore all'8% contro un residuo del 40% che si ha con procedimenti che prevedono l'uso di soluzioni di cloruro ferrico (FeCl3-6H20). It should also be noted that the use of ferric chlorosulfate of mineral origin involves a very low content of chlorides in the residual liquid of the process, if compared with that obtained starting from the formulations of ferric salts of the known processes. This makes the treatment of waste residues easier and compatible with the limits imposed by law. For example, ferric chlorosulfate has a chloride residue of less than 8% compared to a residue of 40% that occurs with processes involving the use of ferric chloride solutions (FeCl3-6H20).
Il trovato risolve così il problema proposto conseguendo i vantaggi anzidetti rispetto ai procedimenti noti. The invention thus solves the problem proposed by achieving the aforementioned advantages with respect to known processes.
Claims (7)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT97PD000236A IT1296242B1 (en) | 1997-10-28 | 1997-10-28 | PROCEDURE FOR THE ELIMINATION OF METAL CORE IN COPPER, ALUMINUM, IRON OR THEIR ALLOYS IN THE PRODUCTION OF HOLLOW METAL OBJECTS |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| IT97PD000236A IT1296242B1 (en) | 1997-10-28 | 1997-10-28 | PROCEDURE FOR THE ELIMINATION OF METAL CORE IN COPPER, ALUMINUM, IRON OR THEIR ALLOYS IN THE PRODUCTION OF HOLLOW METAL OBJECTS |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| ITPD970236A0 ITPD970236A0 (en) | 1997-10-28 |
| ITPD970236A1 true ITPD970236A1 (en) | 1999-04-28 |
| IT1296242B1 IT1296242B1 (en) | 1999-06-18 |
Family
ID=11391939
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| IT97PD000236A IT1296242B1 (en) | 1997-10-28 | 1997-10-28 | PROCEDURE FOR THE ELIMINATION OF METAL CORE IN COPPER, ALUMINUM, IRON OR THEIR ALLOYS IN THE PRODUCTION OF HOLLOW METAL OBJECTS |
Country Status (1)
| Country | Link |
|---|---|
| IT (1) | IT1296242B1 (en) |
-
1997
- 1997-10-28 IT IT97PD000236A patent/IT1296242B1/en active IP Right Grant
Also Published As
| Publication number | Publication date |
|---|---|
| ITPD970236A0 (en) | 1997-10-28 |
| IT1296242B1 (en) | 1999-06-18 |
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