CN109487085B - Process for recovering palladium and platinum by rotary pyrogenic process - Google Patents
Process for recovering palladium and platinum by rotary pyrogenic process Download PDFInfo
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- CN109487085B CN109487085B CN201811575910.7A CN201811575910A CN109487085B CN 109487085 B CN109487085 B CN 109487085B CN 201811575910 A CN201811575910 A CN 201811575910A CN 109487085 B CN109487085 B CN 109487085B
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B7/00—Working up raw materials other than ores, e.g. scrap, to produce non-ferrous metals and compounds thereof; Methods of a general interest or applied to the winning of more than two metals
- C22B7/006—Wet processes
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
- C22B11/00—Obtaining noble metals
- C22B11/04—Obtaining noble metals by wet processes
- C22B11/042—Recovery of noble metals from waste materials
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- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P10/00—Technologies related to metal processing
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Abstract
The invention relates to a process for recovering palladium and platinum by a rotary pyrogenic process. The invention provides a process for recovering palladium and platinum from a material containing palladium and platinum, and particularly relates to a method for enriching palladium and platinum metal by fermenting an ash material containing palladium and platinum after incineration and grinding together with flour and zymogen, then adding a catalyst to incinerate a metal trapping agent in a high-temperature rotating manner and melting the catalyst at a high temperature. The process provided by the invention is used for recovering palladium and platinum from the ash powder of the aqua regia refractory material containing palladium and platinum, so that the treatment period is shortened, the yield of three wastes is reduced, and the enrichment rate is effectively improved.
Description
Technical Field
The invention relates to the precious metal metallurgy industry, in particular to a process for recovering palladium and platinum by a rotary pyrogenic process.
Background
The noble metal palladium platinum is widely applied to industries such as agriculture, petroleum industry, military industry, high and new technology and the like due to the excellent physical and chemical properties of the noble metal palladium platinum. Particularly, with the rapid development of technology in recent years, the demand of noble metal platinum in various industries has increased dramatically. At the present stage, the main sources of the noble metal palladium platinum are mineral resources and secondary resources. The mineral resources of the precious metals palladium and platinum are extremely limited, and in addition, the raw ores are low in grade and mostly paragenic ores, so that the precious metals palladium and platinum are extracted by the mineral resources to meet the development requirements of the society, and a situation that the precious metals palladium and platinum are difficult to follow is presented. Therefore, the secondary resources of palladium and platinum must be effectively recycled to relieve the current situation that the precious metals of palladium and platinum are in short supply and scarce mineral resources. The reutilization of the noble metal palladium and platinum is realized, the method has great significance for relieving the difficult situation of supply and demand of the noble metal palladium and platinum and has positive significance for environmental protection.
Many researchers have searched and published relevant patents on the recovery method of platinum-palladium metal, but the research on the recovery method of aqua regia difficult to treat materials in the prior art is less. The aqua regia material which is difficult to treat is characterized by low content of noble metals (generally, the content of the noble metals in each ton is less than 100g) and high content of base metals and amphoteric oxides, if the material is leached by aqua regia/chemical precipitation, the aim of enriching the noble metals cannot be achieved, the enrichment rate is generally less than 50%, the yield of three wastes in the process is high, and the treatment period is long. The material has the problems of high recovery cost, low recovery rate, long recovery period and the like, the recovery rate is not high, secondary resources containing palladium-platinum metal cannot be fully utilized, and resource waste is caused. The invention explores a recovery process specially aiming at the material, has high enrichment rate on noble metals and less three-waste yield, and is an effective method.
Disclosure of Invention
The method aims to solve the problems that in the prior art, the recovery of palladium-platinum metal in the aqua regia material difficult to treat is low in palladium-platinum enrichment rate, long in treatment period and high in three-waste yield, so that secondary resources containing the palladium-platinum metal cannot be fully utilized, and resource waste is caused. Aiming at the problems, the invention researches a recovery treatment process specially aiming at the materials, and can efficiently enrich palladium and platinum in secondary resources of aqua regia difficult-to-treat materials with low palladium and platinum contents. The technical scheme of the invention is as follows:
a process for recovering palladium and platinum by a rotary pyrogenic process is used for refining and recovering palladium and platinum from a material containing palladium and platinum, and comprises the following specific steps:
a. burning the material containing palladium and platinum for 4-6 hours, taking out and grinding into ash powder;
b. mixing the ash powder with a chemical coagulant, adding water, stirring, placing in a constant temperature box for fermentation, keeping the temperature of the constant temperature box at 30-37 ℃, and fermenting for 4-8 hours to obtain a cake-shaped substance;
c. feeding the cake-like material into a rotary kiln, the total volume of the cake-like material fed being less than the volume of the rotary kiln
Then adding a mixed material of a metal trapping agent and a catalyst;
d. closing the furnace door of the rotary furnace, raising the temperature to 1300-1700 ℃, and then starting to rotate at constant temperature for 5-7 hours;
e. taking out all the materials in the rotary furnace, cooling and taking out the copper alloy object;
f. palladium-platinum metal is extracted from the copper alloy object by a chemical purification method or an electrolytic purification method.
Further, the chemical coagulant in step b includes flour and yeast powder. Mixing the ash powder and the yeast powder, adding the flour into the mixture, fermenting, placing the mixture uniformly stirred with the flour for a period of time by using the yeast powder, fermenting, filling gaps in the dough, fully dispersing the ash powder, improving the enrichment rate of noble metals and reducing loss.
Further, the volume ratio of the ash powder to the chemical coagulant in the step b is 1: 10.
Preferably, the metal collector in step c is crushed copper, and the content of copper in the crushed copper is not lower than 80%.
Further, the weight ratio of the catalyst to the copper scraps was 3: 1.
Further, the weight ratio of the cake-like substance to the mixed material is 2: 1.
Further, the catalyst in step c comprises sodium peroxide, sodium carbonate, borax and a slag former, wherein the slag former is one or a mixture of a plurality of shell powder, carbon powder and gypsum. The base metals of iron, aluminum, tin, lead, chromium, zinc and the like in the ash powder can be removed to obtain the palladium-platinum enrichment with higher purity.
Further, the constant temperature in the step d is 1000-.
Further, the temperature of incineration in the step a is 500-800 ℃.
Has the advantages that: the invention provides a process for recovering palladium and platinum by a rotary pyrogenic process, which is used for extracting and recovering palladium and platinum from ash powder of a royal water refractory material containing palladium and platinum.
Detailed Description
The following detailed description of the invention is provided to enable further understanding of the nature and technical means of the invention, as well as the specific objects and functions attained by the invention.
A process for recovering palladium and platinum by a rotary pyrogenic process is used for refining and recovering palladium and platinum from a material containing palladium and platinum, and comprises the following specific steps:
a. burning the material containing palladium and platinum for 4-6 hours, taking out and grinding into ash powder;
b. mixing the ash powder with a chemical coagulant, adding water, stirring, placing in a constant temperature box for fermentation, keeping the temperature of the constant temperature box at 30-37 ℃, and fermenting for 4-8 hours to obtain a cake-shaped substance;
c. feeding the cake-like material into a rotary kiln, the total volume of the cake-like material fed being less than the volume of the rotary kiln
Then adding a mixed material of a metal trapping agent and a catalyst;
d. closing the furnace door of the rotary furnace, raising the temperature to 1300-1700 ℃, and then starting to rotate at constant temperature for 5-7 hours;
e. taking out all the materials in the rotary furnace, cooling and taking out the copper alloy object;
f. palladium-platinum metal is extracted from the copper alloy object by a chemical purification method or an electrolytic purification method.
Further, the chemical coagulant in step b includes flour and yeast powder. Mixing the ash powder and the yeast powder, adding the flour into the mixture, fermenting, placing the mixture uniformly stirred with the flour for a period of time by using the yeast powder, fermenting, filling gaps in the dough, fully dispersing the ash powder, improving the enrichment rate of noble metals and reducing loss.
Further, the volume ratio of the ash powder to the chemical coagulant in the step b is 1: 10.
Preferably, the metal collector in step c is crushed copper, and the content of copper in the crushed copper is not lower than 80%.
Further, the weight ratio of the catalyst to the copper scraps was 3: 1.
Further, the weight ratio of the cake-like substance to the mixed material is 2: 1.
Further, the catalyst in step c comprises sodium peroxide, sodium carbonate, borax and a slag former, wherein the slag former is one or a mixture of a plurality of shell powder, carbon powder and gypsum. The base metals of iron, aluminum, tin, lead, chromium, zinc and the like in the ash powder can be removed to obtain the palladium-platinum enrichment with higher purity.
Further, the constant temperature in the step d is 1000-.
Further, the temperature of incineration in the step a is 500-800 ℃.
The process is further described by the following examples:
example 1:
burning 10kg of materials containing palladium and platinum for 5 hours, taking out and grinding the materials into ash powder, wherein the burning temperature is 500 ℃, stirring the ash powder, 5kg of flour and 500g of yeast powder, placing the materials into a thermostat, fermenting the materials for 4 hours at 30 ℃ to form a cake-shaped object, placing the cake-shaped object into a rotary furnace with the volume of 1000L, adding a metal trapping agent and a catalyst, wherein the metal trapping agent is crushed copper, the amount of the added crushed copper is 2kg, the catalyst comprises sodium peroxide, sodium carbonate, borax, shell powder and carbon powder, the amount of the added catalyst is 6kg, closing a furnace door of the rotary furnace, starting to rotate after the temperature is increased to 1000 ℃, taking out all the materials in the rotary furnace after rotating for 5 hours at constant temperature, cooling and taking out a copper alloy object, utilizing a chemical wet method (namely, adopting aqua regia solution to dissolve copper alloy, and then respectively producing precipitates with a chemical reagent and noble metals to separate noble metals, separated precious metal is then chemically wet purified) to extract palladium platinum metal from the alloy object.
After the treatment, most of palladium and platinum in the material is enriched in the copper alloy, the enrichment rate is as high as 98.1%, and the residual rate of palladium and platinum in the slag is lower than 2%.
Example 2:
burning 10kg of materials containing palladium and platinum for 5 hours, taking out and grinding the materials into ash powder, wherein the burning temperature is 600 ℃, stirring the ash powder, 5kg of flour and 500g of yeast powder, fermenting the materials for 4 hours at 35 ℃ in a thermostat for forming a cake-shaped object, putting the cake-shaped object into a rotary furnace with the volume of 1000L, adding a metal trapping agent and a catalyst, wherein the metal trapping agent is crushed copper, the amount of the added crushed copper is 2kg, the catalyst comprises sodium peroxide, sodium carbonate, borax, shell powder and carbon powder, the amount of the added catalyst is 6kg, closing a furnace door of the rotary furnace, starting to rotate after the temperature is increased to 1200 ℃, taking out all the materials in the rotary furnace after rotating for 6 hours at constant temperature, cooling and taking out a copper alloy object, and extracting the palladium and platinum metal from the alloy object by using a chemical wet purification method.
After the treatment, most of palladium and platinum in the material is enriched in the copper alloy, the enrichment rate is as high as 98.3%, and the residual rate of palladium and platinum in the slag is lower than 2%.
Example 3:
burning 10kg of materials containing palladium and platinum for 6 hours, taking out and grinding the materials into ash powder, wherein the burning temperature is 700 ℃, stirring the ash powder, 5kg of flour and 500g of yeast powder, fermenting the materials for 5 hours at 37 ℃ in a thermostat for forming a cake-shaped object, putting the cake-shaped object into a rotary furnace with the volume of 1000L, adding a metal trapping agent and a catalyst, wherein the metal trapping agent is crushed copper, the amount of the added crushed copper is 2kg, the catalyst comprises sodium peroxide, sodium carbonate, borax, shell powder and carbon powder, the amount of the added catalyst is 6kg, closing a furnace door of the rotary furnace, starting to rotate after the temperature is increased to 1400 ℃, taking out all the materials in the rotary furnace after rotating for 6 hours at constant temperature, cooling and taking out a copper alloy object, and extracting the palladium and platinum metal from the alloy object by using a chemical wet purification method.
After the treatment, most of palladium and platinum in the material is enriched in the copper alloy, the enrichment rate is as high as 98.5%, and the residual rate of palladium and platinum in the slag is lower than 2%.
Example 4:
burning 10kg of materials containing palladium and platinum for 6 hours, taking out and grinding the materials into ash powder, wherein the burning temperature is 800 ℃, stirring the ash powder, 5kg of flour and 500kg of yeast powder, fermenting the materials for 4 hours at 37 ℃ in a thermostat for forming a cake-shaped object, putting the cake-shaped object into a rotary furnace with the volume of 1000L, adding a metal trapping agent and a catalyst, wherein the metal trapping agent is crushed copper, the amount of the added crushed copper is 2kg, the catalyst comprises sodium peroxide, sodium carbonate, borax, shell powder and carbon powder, the amount of the added catalyst is 6kg, closing a furnace door of the rotary furnace, starting to rotate after the temperature is increased to 1500 ℃, taking out all the materials in the rotary furnace after rotating for 6 hours at constant temperature, cooling and taking out a copper alloy object, and extracting the palladium and platinum metal from the alloy object by using a chemical wet purification method.
After the treatment, most of palladium and platinum in the material is enriched in the copper alloy, the enrichment rate is as high as 98.8%, and the residual rate of palladium and platinum in the slag is lower than 2%.
From the above examples 1-4, it can be seen that the process provided by the present invention can be used for recovering palladium and platinum from ash powder of aqua regia refractory material containing palladium and platinum, thereby shortening the treatment period, reducing the yield of three wastes, and effectively increasing the enrichment ratio of noble metals.
Claims (8)
1. A process for recovering palladium and platinum by a rotary pyrogenic process is used for refining and recovering palladium and platinum from a material containing palladium and platinum, and comprises the following specific steps:
a. burning the material containing palladium and platinum for 4-6 hours, taking out and grinding into ash powder;
b. mixing the ash powder with a chemical coagulant, adding water, stirring, placing in a thermostat, and fermenting at constant temperature to obtain a cake-like substance, wherein the chemical coagulant comprises flour and yeast powder;
c. feeding the cake-like material into a rotary kiln, the total volume of the cake-like material fed being less than the volume of the rotary kiln
Then adding a mixed material of a metal trapping agent and a catalyst;
d. closing the furnace door of the rotary furnace, raising the temperature to 1300-1700 ℃, and then starting to rotate at constant temperature for 5-7 hours;
e. taking out all the materials in the rotary furnace, and taking out the alloy object after cooling;
f. palladium-platinum metal is extracted from the alloy object by a chemical purification method or an electrolytic purification method.
2. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 1, wherein: and the volume ratio of the ash powder to the chemical coagulant in the step b is 1: 10.
3. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 1, wherein: in the step c, the metal trapping agent is crushed copper, and the content of copper in the crushed copper is not lower than 80%.
4. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 3, wherein: the weight ratio of the catalyst to the copper crushed aggregates is 3: 1.
5. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 1, wherein: the weight ratio of the cake-like material to the mixed material is 2: 1.
6. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 1, wherein: the catalyst in the step c comprises sodium peroxide, sodium carbonate, borax and a slagging agent, wherein the slagging agent is one or a mixture of a plurality of shell powder, carbon powder and gypsum.
7. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 1, wherein: the constant temperature in the step d is 1000-.
8. The process for recovering palladium and platinum by rotary pyrometallurgy as claimed in claim 1, wherein: the temperature for incineration in step a is 500-.
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| CN107699699A (en) * | 2017-10-10 | 2018-02-16 | 东北大学 | The method of zinc abstraction clinker melting and reducing production |
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- 2018-12-22 CN CN201811575910.7A patent/CN109487085B/en active Active
Patent Citations (6)
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| CN101850354A (en) * | 2009-03-31 | 2010-10-06 | 王进民 | Process for utilizing all components in waste circuit boards |
| CN104164526A (en) * | 2014-07-31 | 2014-11-26 | 甘肃酒钢集团宏兴钢铁股份有限公司 | Short-flow direct reduction technology for producing molten iron from iron ore |
| CN105861851A (en) * | 2015-01-21 | 2016-08-17 | 昆明冶金高等专科学校 | Method for enriching platinum group metal secondary resource with high efficiency |
| CN105886768A (en) * | 2015-01-25 | 2016-08-24 | 昆明冶金高等专科学校 | Method for efficiently enriching precious metal from electronic waste |
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| CN107699699A (en) * | 2017-10-10 | 2018-02-16 | 东北大学 | The method of zinc abstraction clinker melting and reducing production |
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