Recovering silver from touchscreen glass with ALS2
Touchscreen panels look almost empty: a sheet of glass, a transparent conductive coating and a fine network of printed tracks. Hidden within that thin structure can be silver-bearing paste used for busbars, edge contacts and conductive traces. Recovering it is technically demanding because the precious metal is distributed in very small quantities across a large, fragile and mixed-material surface.
ALS2, Ikoi S.p.A.’s acidless separation technology, is designed for this kind of complex electronic waste stream. Its purpose is to liberate and concentrate valuable metals while reducing dependence on conventional acid-based refining. For Australian recyclers handling phones, tablets, payment terminals and display assemblies, the approach offers a route towards more controlled precious-metals recovery and cleaner resource management.
Where silver is found in a touchscreen panel
A modern touch panel may combine cover glass, an adhesive layer, transparent electrodes, printed silver conductors, an insulating film and a flexible printed circuit. The transparent electrode is often based on indium tin oxide, commonly called ITO, rather than silver. Silver is more likely to occur in narrow busbars, contact pads or screen-printed conductive lines that connect the transparent electrode to the controller electronics.
This distinction matters when estimating recovery value. A panel can contain several valuable elements, yet the metal may be spread in a coating measured in micrometres. Silver-bearing lines can be covered by polymer films or bonded to glass, so simply removing the circuit board does not capture all of the available material. The indium and tin in ITO also require a different recovery strategy from silver.
ALS2 is therefore relevant as a separation route rather than a simple crushing operation. The objective is to prepare the feed, expose the valuable fraction and produce a concentrated output suitable for downstream refinement. The exact yield depends on panel design, generation, contamination, collection quality and the share of genuinely silver-bearing components.
Preparing glass panels for controlled processing
The first stage is careful dismantling and sorting. Touchscreen glass should be separated from batteries, speakers, cameras, printed circuit boards and aluminium frames where practical. Removing these components limits cross-contamination and helps an operator understand the composition of each batch. Damaged screens also need controlled handling because sharp glass fragments and residual battery parts create safety risks.
After dismantling, the panel is reduced to a size and form that allows the conductive layers to be liberated. Mechanical treatment can expose the printed traces, but excessive force may create fine glass dust, smear polymers across the feed or distribute metal particles into an unrecoverable fraction. A well-designed process balances liberation with particle control and uses suitable extraction, screening and housekeeping measures.
Australian facilities may receive mixed loads from mobile-phone repairers in Sydney, electronics refurbishers in Melbourne or commercial equipment replacement programmes in Brisbane. These sources rarely provide identical panels. A sorting protocol that separates smartphone glass, tablet glass, point-of-sale displays and larger industrial touchscreens can improve feed consistency before ALS2 processing begins.
How an acidless separation route handles the metal
The ALS2 concept centres on separating valuable materials without relying on conventional aggressive acid leaching as the primary recovery method. Once the touchscreen material has been prepared, the process works through controlled physical and chemical separation steps that aim to move the silver-bearing fraction away from glass, plastics, adhesives and other low-value materials.
In practical terms, liberation is followed by concentration. Glass and polymer-rich material can be directed into different streams from the fine fraction containing conductive residues. Process control is essential: particle size, moisture, residence time and feed composition influence how effectively silver-bearing material is collected. The technology is intended to create a compact recovery plant in which these stages can be managed close to the source of the waste.
Acidless does not mean that every input, output or operation is free from environmental controls. Dust capture, worker protection, wastewater management and residue classification remain important. The advantage is that the process is designed to reduce the hazards and infrastructure demands associated with traditional acid-intensive treatment, supporting a more contained and potentially easier-to-operate recovery system.
From conductive residue to recoverable silver
After concentration, the silver-bearing output requires further upgrading. The process must remove remaining glass particles, organic binders and base-metal contamination so that silver can be recovered in a form with a predictable grade. Depending on the feed and the plant configuration, this may involve additional separation, controlled reaction stages and final refining.
The key performance measure is not simply the amount of silver detected in a laboratory sample. A viable operation also considers recovery rate, concentrate quality, energy use, residue volume, labour requirements and the value of materials lost in other streams. A high-grade output with poor recovery may be less useful than a slightly lower-grade product that captures substantially more of the silver entering the plant.
This is where traceability helps. Each batch can be weighed, characterised and tracked from incoming screens through to separated fractions. Testing can identify whether a shipment contains silver-print conductors, mainly ITO-coated glass or a mixture of both. Such information supports realistic commercial decisions and avoids treating every touchscreen panel as if it had the same precious-metal content.
Why the approach suits Australian e-waste systems
Australia has a dispersed geography and a strong dependence on collection networks. Valuable electronic waste may move from metropolitan repair hubs to regional consolidation sites before reaching a specialist processor. Transporting low-density screens over long distances can reduce the economics of recovery, especially when the material has already been stripped of its circuit boards. Compact separation equipment can help place more processing capability near collection or pre-processing centres.
The local regulatory setting also rewards disciplined handling. The National Television and Computer Recycling Scheme has increased awareness of electronics recycling, while state and territory rules govern waste transport, storage and processing. Touchscreen assemblies are not identical to televisions or computers, so operators need to classify their incoming material correctly and maintain documented procedures for glass, plastics, batteries and metal-bearing residues.
Weather and operating conditions are relevant as well. A facility in Perth may manage dry, dusty conditions, while a site near Cairns faces higher humidity and corrosion risk. In Adelaide, Melbourne or Sydney, limited industrial space can make a compact plant more attractive than a large conventional refinery. These practical realities make process simplicity, enclosure, dust control and modular expansion important design considerations.
Lessons from overseas operators can also inform local deployment, particularly when companies review early adoption lessons before committing to new separation equipment. Northern European experience can offer useful guidance on feed preparation, staff training, material testing and integration with existing recycling lines, while Australian operators still need to validate performance against their own panel mix.
Building a reliable recovery workflow
A touchscreen recovery line should begin with a clear material specification. The operator can define acceptable panel types, contamination limits and minimum batch sizes, then use sampling to estimate silver, glass, polymer and other metal content. This reduces surprises and gives the ALS2 process a more stable feed.
The following comparison shows how the main material streams differ in a practical plant setting:
| Material stream | Typical contents | Main processing concern | Useful outcome |
|---|---|---|---|
| Touchscreen glass with printed conductors | Glass, silver-bearing traces, polymers | Fragile layers and fine particles | Concentrated conductive residue |
| ITO-coated transparent glass | Indium, tin, glass and coatings | Silver may be absent or minor | Separate non-silver mineral/metal fraction |
| Flexible display or sensor film | Polymer, conductive coating and adhesives | Heat sensitivity and contamination | Sorted polymer-rich or conductive fraction |
| Attached circuit board | Copper, gold, tin, solder and components | Higher base-metal and component content | Separate electronics feed for dedicated recovery |
| Mixed damaged assemblies | Glass, plastics, batteries and metals | Safety, sorting and variable chemistry | Pre-processed batches suitable for controlled treatment |
A commercial assessment should combine laboratory testing with a small pilot campaign. Samples from Australian phones, tablets, transport ticketing equipment and retail payment terminals can reveal how much the incoming feed differs from published assumptions. The results help determine whether silver recovery should be performed on site, at a regional hub or after consolidation with other conductive electronic materials.
ALS2’s development under the European Union’s Horizon 2020 research and innovation programme reflects the wider aim of improving resource efficiency in electronic waste treatment. For an Australian project, the same principle can be applied locally: recover more value from existing waste, reduce hazardous processing requirements and keep material data visible throughout the chain.
ALS2 provides a pathway for treating the fine, dispersed silver found in conductive touchscreen traces as a recoverable resource rather than an incidental residue. To evaluate the opportunity, recyclers, manufacturers and waste operators can review their panel streams, arrange representative sampling and discuss a pilot configuration with the ALS2 project team. A measured trial is the practical next step towards a safer, compact and commercially grounded precious-metals recovery operation.