Recovering gold from SIM cards with ALS2 technology
SIM cards and smart card modules are small, but their electronic contacts can contain valuable recoverable metals. Gold is used where reliable conductivity and resistance to corrosion are essential, including contact surfaces, bonding points, and selected components within secure identification modules. When millions of cards reach the end of their service life, these thin layers become a secondary resource within the wider electronic waste stream.
The difficulty is concentration. A card contains polymers, adhesives, silicon, copper, nickel, and other materials around a very small quantity of precious metal. Conventional recovery routes can require several chemical stages, generate hazardous residues, and make it difficult to process low-volume or highly mixed feedstock economically. A practical recycling solution must therefore combine selective recovery with careful preparation and efficient material handling.
ALS2 is designed for acidless separation of precious metals from electronic scrap and WEEE-related streams. Applied to SIM card chips and smart card modules, the technology can support a compact recovery plant that reduces reliance on aggressive acids while helping operators retain greater control over the process, residues, and recovered fractions.
Where gold is found in card waste
A traditional SIM card typically contains a plastic body, an embedded integrated circuit, a metal contact surface, and bonding connections between the chip and its substrate. The visible gold colour on the contact area does not necessarily indicate a thick layer of metal. In most cases, the gold is a very thin coating applied over nickel and other base materials, while additional gold may occur in microscopic bonding wires or internal connection points.
Smart cards can contain a more complex module. Payment cards, access badges, identification cards, transport passes, and secure authentication cards may use contact pads, embedded chips, antenna connections, and multilayer substrates. Their construction varies by manufacturer and application, so the value of a batch depends on card type, age, design, and the proportion of modules rather than simply on total weight.
This variation makes sampling and classification important. Whole cards can occupy significant storage space while carrying only a small amount of precious metal. Separating card bodies from chip modules, or at least creating a consistent feedstock, helps an operator assess grade, select the right pre-treatment, and avoid processing unwanted plastic with the metal-bearing fraction.
Preparing SIM and smart card modules
Preparation begins with collection and sorting. SIM cards should be separated from packaging, paper carriers, memory cards, chargers, and unrelated plastic components. Smart card waste benefits from additional classification by application because a bank card, access badge, and industrial identification card may contain different module designs and metal concentrations.
Mechanical size reduction can expose the embedded module and liberate contact-bearing pieces, but excessive shredding may disperse fine metal-bearing particles into a broad plastic fraction. A controlled approach is preferable: remove or loosen the card body, concentrate the module, and use screened fractions that can be handled consistently. The right configuration depends on feed composition, throughput, and the degree of liberation required.
Operators should also account for dust, static charge, and mixed-material contamination. Enclosed conveying, extraction, and appropriate filtration help protect workers and keep fine particles within the process. Any recovered plastic fraction should be assessed separately, while copper- and nickel-bearing materials can be directed to suitable downstream routes instead of being treated as disposable residue.
How acidless separation fits the recovery process
ALS2 can be integrated after sorting and preparation to treat the concentrated electronic fraction. Its acidless approach is relevant to card recycling because the gold is present in small quantities alongside base metals and non-metallic materials. Rather than relying on an acid bath as the central separation step, the system is intended to use controlled process stages that separate valuable material while reducing the chemical burden associated with conventional refining.
The process configuration should be established through representative trials. A sample of SIM modules or smart card chips can be characterized for gold content, substrate composition, particle size, and the presence of copper, nickel, or other metals. Test work then helps determine the appropriate sequence, residence conditions, screening points, and recovery controls for that particular feedstock.
The result is a more defined precious-metal fraction that can be assayed and sent for final refining or further treatment. ALS2 does not remove the need for sound feed preparation, quality control, or downstream verification. Instead, it offers a route for placing those activities within a compact and more manageable recovery system.
| Feed characteristic | Recycling consideration | Role of an ALS2-based route |
|---|---|---|
| Thin gold-plated contacts | Gold is valuable but spread across a large base-metal surface | Concentrate and separate the metal-bearing fraction |
| Embedded chip modules | Silicon, resin, copper, nickel, and gold may occur together | Use controlled preparation and process testing |
| Mixed SIM card batches | Designs and gold content vary by supplier and generation | Sort, sample, and adjust the treatment configuration |
| Smart cards with multiple layers | Laminates and adhesives can hinder liberation | Apply suitable size reduction and screening |
| Fine recovered fraction | Dust and cross-contamination can affect yield and safety | Use enclosed handling, filtration, and assay control |
| Plastic card bodies | Most polymer mass contains little precious metal | Remove or manage separately from the metal-rich stream |
Environmental and operational advantages
For card recyclers, the environmental case is linked to the scale and composition of the material. A conventional acid-based route may require storage of corrosive reagents, specialized equipment, neutralization, and management of liquid effluents. An acidless process can reduce these requirements, particularly when the feed is first concentrated and the plant is designed around dry or controlled separation stages.
Lower chemical complexity can also support safer day-to-day operation. Fewer corrosive inputs may simplify operator training, maintenance planning, and regulatory management, although every installation still needs appropriate safeguards for dust, heat, electrical equipment, residues, and any process-specific materials. Acidless does not mean risk-free; it means the risk profile can be different and potentially easier to manage.
The sustainability benefit extends beyond the plant boundary. Recovering gold from discarded cards reduces the need to rely solely on primary mining for new material and keeps embedded resources in circulation. Energy, transport, and residue impacts still need to be measured, but a local or regional recovery unit can be useful where card waste is generated in regular, traceable quantities.
Designing a reliable feedstock strategy
A viable project starts with supply rather than equipment alone. Telecommunications operators, card manufacturers, financial institutions, secure-document producers, and electronics dismantlers may generate different grades of SIM and smart card waste. Agreements should define material type, contamination limits, data-security requirements, delivery frequency, and ownership of the recovered metals.
Data protection is especially important for payment, identity, and access cards. Before physical treatment, organizations may need documented destruction procedures that render stored information unusable. The physical recovery process should be integrated with secure collection, chain-of-custody records, and evidence of destruction where required by company policy or regulation.
Assay results should be tracked against incoming weight, prepared feed, recovered precious-metal fraction, and final refinery settlement. These measurements reveal whether losses occur during sorting, liberation, separation, or handling. They also make it possible to compare different card categories and decide whether a mixed stream or a dedicated batch produces the best operational return.
The same discipline used for other fine precious-metal residues can be valuable here. For example, experience with jewellery sweep recovery shows why dust collection, sampling, and fraction control matter when precious metals are distributed through a large amount of low-value material. Card modules present a different feed, but the principle of protecting every metal-bearing fraction remains relevant.
Practical controls for higher recovery
A compact plant can make SIM and smart card recycling more accessible, but its performance depends on repeatable operating practices. The following controls help establish a sound starting point:
- Sort by card and module type: Keep SIM cards, payment cards, access badges, and other electronic modules in identifiable batches where possible.
- Characterize before scaling: Use representative sampling and laboratory assays to establish gold grade, base-metal content, moisture, and non-metallic contamination.
- Liberate selectively: Choose cutting, granulation, or screening conditions that expose the module without unnecessarily generating difficult-to-handle fines.
- Control dust and residues: Use enclosed transfer points, extraction, filtration, and documented cleaning procedures to prevent precious-metal losses.
- Reconcile each batch: Compare input mass and assay data with recovered fractions, residue results, and refinery reports.
These measures also support process optimization. If the gold recovery rate is below expectation, the cause may be incomplete module liberation, loss during screening, excessive dilution with plastic, or inaccurate sampling rather than a problem in the principal separation stage. A clear material balance makes those causes easier to distinguish.
The equipment should be selected around the actual feed profile. A recycler handling a steady stream of telecom SIM cards may need a different preparation and throughput arrangement from a secure-document contractor processing occasional batches of mixed smart cards. Modular capacity, accessible inspection points, and the ability to adjust the process for new card designs can protect the investment as product formats change.
Turning discarded cards into a controlled resource
Gold in SIM card chips and smart card modules is small in physical volume but significant when aggregated across large waste streams. The strongest recovery strategy combines secure collection, selective dismantling, accurate sampling, controlled liberation, and a separation technology suited to mixed electronic materials. ALS2 provides a basis for pursuing that strategy without making acid use the defining feature of the plant.
Ikoi S.p.A.’s acidless separation technology is positioned for organizations seeking cleaner precious-metal recovery from electronic waste and WEEE streams. With representative testing and a properly specified preparation line, discarded cards can move from a difficult mixed waste into a measurable, traceable feedstock for precious-metal recovery.
Begin with a sample assessment of your SIM cards or smart card modules, map the material flow, and define the recovery targets before planning full-scale equipment. A disciplined pilot can establish grade, yield, residue quality, and operating requirements while creating a practical route toward safer and more resource-efficient recycling.