Copper Leaching via Chloride-Bromide Oxidation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current copper sulfide ore processing methods, such as dry processing and existing wet processing techniques, face challenges including high fuel consumption, inefficiencies due to impurity levels, and difficulties in treating low-grade copper materials, particularly with chloride baths which are costly and complex to manage.
Innovation Solution
A method involving leaching copper from copper sulfide ore using a chloride bath with an acid solution containing alkali metal or earth metal chlorides and bromides, utilizing the oxidizing power of iron or copper ions under atmospheric pressure and temperature below the boiling point, without specific oxidants, to achieve high copper extraction rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If dry processing is used to melt copper sulfide ore at high temperature, then copper sulfide can be purified and separated from impurities, but fuel consumption increases significantly and exhaust gas treatment is required
Solution Approach 1:
The invention changes the fundamental processing parameters from high-temperature melting (dry processing) to ambient temperature leaching (wet processing). By using chloride-bromide aqueous solutions at ambient temperature with atmospheric oxygen as oxidant, the process achieves copper extraction without the energy-intensive melting step, thereby dramatically reducing fuel consumption while maintaining effective separation of copper from impurities
Solution Approach 2:
The invention replaces the mechanical/thermal system of high-temperature melting with a chemical system based on oxidative leaching. Instead of using thermal energy to melt and separate copper, the process uses chemical reactions in aqueous chloride-bromide solutions to dissolve copper selectively, substituting thermal processing with chemical processing to achieve the same purification goal with lower energy input
2Manufacturing precision
If high temperature purifying treatment is applied after melting, then copper can be purified, but treatment efficiency decreases due to increased impurity grade in matte
Solution Approach 1:
The invention performs preliminary selective leaching of copper from the ore using chloride-bromide solutions before any impurity concentration occurs. By extracting copper in its soluble chloride form at ambient temperature, the process prevents the formation of impurity-rich matte that would require subsequent high-temperature purifying treatments, thereby maintaining high treatment efficiency throughout the process
Solution Approach 2:
The invention extracts copper from the ore matrix using selective oxidative leaching in chloride-bromide aqueous solutions. This extraction occurs at ambient temperature and selectively removes copper while leaving most impurities behind in the solid residue, achieving purification without the need for high-temperature treatment steps that would reduce efficiency
3Manufacturing precision
If conventional sulfuric acid leaching is used on copper sulfide ore, then some copper can be extracted, but the reaction rate is slow and noble metals cannot be obtained
Solution Approach 1:
The invention changes the leaching chemistry from sulfuric acid to chloride-bromide aqueous solutions. This parameter change fundamentally alters the reaction mechanism, enabling rapid oxidative dissolution of copper sulfide minerals at ambient temperature. The chloride-bromide system provides much faster reaction kinetics compared to conventional sulfuric acid leaching, while also allowing recovery of noble metals that would otherwise remain trapped in the ore matrix
Solution Approach 2:
The invention uses a composite leaching system combining chloride and bromide ions in aqueous solution. This composite chemical system provides synergistic effects where bromide enhances the oxidative power and selectivity of the leaching process, dramatically increasing the reaction rate for copper extraction while also enabling noble metal recovery, overcoming the limitations of single-acid systems
4Productivity
If high temperature and high pressure are applied to enlarge copper leaching rate, then leaching efficiency improves, but equipment complexity increases and electrodeposited copper quality degrades
Solution Approach 1:
The invention enables the leaching process to proceed rapidly at ambient temperature and atmospheric pressure by using atmospheric oxygen as the oxidant. The chloride-bromide aqueous solution system is self-sufficient, drawing oxygen from the air rather than requiring external oxygen supply systems or pressurized reactors. This self-service approach maintains high copper leaching rates without requiring complex high-temperature and high-pressure equipment
Solution Approach 2:
The invention operates in a simple atmospheric environment using air as the oxygen source. By designing the leaching system to function at ambient temperature and pressure with atmospheric oxygen, the process avoids the need for complex pressurized reactors, temperature control systems, and safety equipment required for high-temperature high-pressure operations, thereby maintaining simplicity while achieving high productivity
5Productivity
If chloride bath is used for copper leaching, then copper extraction rate increases, but reagent cost increases and process control becomes difficult
Solution Approach 1:
The invention introduces bromide ions as an intermediary component in the leaching system. Bromide acts as a mediator that enhances the oxidative power of the chloride system by forming hypobromous acid and other reactive bromine species. This intermediary bromide component enables rapid copper extraction at ambient conditions while the system remains easier to control compared to pure chloride systems, as bromide provides more predictable and stable reaction behavior
Solution Approach 2:
The invention uses a composite chloride-bromide leaching system where the combination of chloride and bromide ions creates a synergistic effect. This composite chemical system provides rapid copper extraction rates while being more controllable than pure chloride systems. The bromide component stabilizes the leaching process and provides a more manageable operational profile, reducing the difficulties associated with pure chloride bath control
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method effectively extracts over 98% copper with reduced reagent costs, simplified equipment needs, and efficient copper recovery, suitable for both high and low-grade copper ores, while minimizing environmental impact and operational complexity.
Implementation Method 1
leaching monovalent copper and divalent copper from the feedstock with use of oxidizing power of at least one of iron ion and copper ion in the acid solution, with air being blown into the acid solution under an atmospheric pressure at a temperature less than a boiling point of the acid solution
Data Source
AI summary
A method of obtaining copper from feedstock includes: providing feedstock into acid solution including chloride and bromide of one of alkali metal and alkali earth metal, and one of chloride of copper and iron and bromide of copper and iron; leaching monovalent copper and divalent copper with use of oxidizing power of at least one of iron ion and copper ion, with air being blown into the acid solution under an atmospheric pressure at a temperature less than a boiling point of the acid solution; solid-liquid separating the acid solution; blowing air into the solution; oxidizing copper in the solution; coprecipitating iron and impurity; extracting copper from the solution from which deposition including the coprecipitate is separated; obtaining the extracted copper into sulfuric acid solution as copper sulfate; obtaining copper from the copper sulfate; and recycling hydrochloric acid generated in the extracting in another copper leaching.