Recovering gold from coaxial connector shells with ALS2
Coaxial cable connector shells are small components, yet they can contain economically significant amounts of precious metal. Gold is usually concentrated on contact surfaces, mating interfaces or plated contact components rather than distributed evenly through the shell itself. The practical question of how ALS2 handles gold from coaxial cable connector shells therefore begins with recognising them as a concentrated urban-mining resource rather than ordinary plastic-bound electronic waste.
ALS2Project, led by Ikoi S.p.A. and supported through the European Union’s Horizon 2020 research and innovation programme, is developing acidless separation technology for recovering precious metals from electronic waste and WEEE streams. Its approach is particularly relevant to businesses seeking compact recovery plants, safer operating conditions and a way to reduce dependence on conventional acid-based refining.
Why connector shells matter
A connector assembly commonly combines a brass, copper, aluminium or steel shell with nickel, silver, tin or gold plating. Some shells carry precious metal across broader surfaces, while others concentrate it on small electrical contacts. Gold coatings can be only fractions of a micrometre thick, making their value largely invisible during a casual inspection of discarded cable.
These components arrive from telecommunications networks, data centres, broadcast equipment, CCTV systems, industrial machinery and vehicles. Each sector uses different connector types, but retired infrastructure eventually produces a mixed stream of cable, plugs, sockets and machine wiring. For recyclers, that creates a valuable yet fragmented source of gold, silver, palladium and other metals.
The commercial significance is amplified by what happens if the material enters a general WEEE shredder. Valuable contact pieces become small particles mixed with plastics, ferrous metals and unrelated alloys. Recovering them later requires additional sorting and increases losses. A dedicated connector stream can give a refinery a much higher concentration of precious-metal-bearing material.
Preparing a clean connector-rich feed
The first stage is controlled cable dismantling. Suitable machinery or manual procedures remove the outer jacket, braided shielding, dielectric insulation and connector bodies while preserving gold-plated contacts. This is more useful than indiscriminate crushing because it separates connector-rich material before the valuable fraction becomes dispersed.
The resulting assemblies then undergo size reduction and classification. Metals are separated from polymers, while ferrous pieces and lower-value fractions can be removed. Processors must retain fine particles because some gold plating detaches during dismantling or crushing. A sound ALS2 feed-preparation design therefore combines component sorting with careful collection of both intact contacts and metal-bearing fines.
Feed consistency determines the quality of the separation. Connectors with different plating systems, painted shells, solder residues or contaminated surfaces may behave differently in sorting and concentration equipment. Representative sampling and assay analysis are needed before a plant is configured, particularly when deciding whether connectors should remain intact or be processed as fines.
The ALS2 treatment pathway
ALS2 focuses on acidless liberation, separation and concentration of precious-metal-bearing material. Its defining feature is the avoidance of a conventional mineral-acid gold dissolve, which distinguishes it from hydrometallurgical routes that dissolve selected metals into highly corrosive solutions before recovering them through precipitation and further purification.
| Consideration | Conventional acid-based refining | ALS2 approach for connector material |
|---|---|---|
| Separation principle | Dissolves metals into acidic liquor, followed by precipitation and purification | Concentrates a precious-metal-bearing fraction without a mineral-acid gold leach |
| Feed preparation | Often receives mixed, shredded electronic waste | Benefits from dismantled cable, recovered connectors and consistent metal-rich feed |
| Chemical profile | May involve aqua regia, sulphuric acid or cyanide-based chemistry | Avoids the corrosive acids and cyanide associated with those routes |
| Waste profile | Produces liquid effluents, neutralisation salts and contaminated residues | Avoids acid-neutralisation waste, while still requiring management of solids and filters |
| Gold-bearing output | Dissolved gold is purified into bullion or doré | Gold-rich concentrate or metal fractions are sent for specialist downstream refining |
| Main operational risk | Reagent exposure, effluent treatment and permitting | Feed consistency, precious-metal capture, dust control and final assay |
The project’s process should be viewed as a concentration stage rather than a direct bullion-producing refinery. Recovered metal fractions can be sent to an accredited refiner for sampling, smelting, electrolytic refining and casting. This division keeps the ALS2 plant focused on its strongest capabilities: sorting a complex feed, capturing small quantities of valuable metal and delivering a manageable intermediate.
The environmental case is substantial but should be described precisely. Eliminating acid dissolution can reduce worker exposure, corrosive liquid handling and the creation of spent acid-neutralisation salts. It does not remove every environmental obligation. Dust capture, fire prevention, responsible handling of non-valuable residues and transparent reporting of recovery performance remain necessary for a credible industrial installation.
Designing a compact recovery plant
A compact plant could sit beside a cable-dismantling facility, municipal e-waste centre or specialist scrap-metal processor. Locating concentration close to the source reduces the cost of transporting low-value connector shells to a distant precious-metals refinery. Only the smaller gold-bearing fraction would need onward movement.
The plant design must integrate feed metering, size classification, separation equipment, dust control and sampling points. Operators also need a clear chain of custody documenting cable origin, connector types, processing conditions and recovered fractions. Such records support both commercial settlement and claims about recycled content in downstream gold.
Economics depend on more than the quoted gold price. Throughput, feed grade, recovery rate, labour, consumables, residue disposal and refinery charges all influence the result. A dedicated connector feed may perform better than mixed WEEE because valuable contacts are already concentrated, but low-grade material or inconsistent plating can still reduce returns. Pilot data from representative Australian streams is therefore more informative than a generic performance claim.
Fit with Australia’s recycling market
Sydney and Melbourne contain substantial concentrations of commercial telecommunications equipment, data-centre infrastructure, office electronics and transport systems. These cities also have established collection networks and sophisticated recycling markets. Coaxial cable removed during building refurbishments, network upgrades and equipment disposal can therefore support a regional connector-recovery supply rather than being scattered across mixed household e-waste.
The Australian market already includes specialist cable processors, scrap-metal merchants, e-waste facilities and bullion refiners. Recovered gold-bearing material would normally be assessed for grade and impurities before being sold to a refinery under agreed assay and settlement terms. Perth’s precious-metals sector, together with established bullion businesses in Sydney and Melbourne, provides a credible domestic route for converting a concentrate into refined metal.
Imports require particular attention. A shipment of used cable may be regulated as waste under Australia’s Waste Management Requirements rather than treated simply as a second-hand product. Federal and state approvals, customs classification, valuation and biosecurity inspection can all affect an import. An Australian operator should confirm the regulatory treatment with the Department of Climate Change, Energy, the Environment and Water, the relevant state authority and a customs broker before arranging a trial shipment.
International experience is also relevant when designing that operating model. AA Europe’s automotive materials context illustrates how European supply chains connect material performance, producer responsibility and circular-economy objectives. The same combination of traceability, manufacturing demand and recycling value can support an Australian model, provided the project is designed around local collection routes and downstream refining contracts.
Turn connector waste into recovered value
A practical first step is to define one dependable feedstock, such as retired telecommunications cable from a Melbourne network upgrade or connector-rich industrial wiring collected in Sydney. The supplier should document cable sources and expected connector types, after which an initial assay can establish the gold-bearing fraction and identify contaminants.
Ikoi and ALS2Project can then assess the material against the demonstrated process configurations, while an Australian laboratory and prospective refinery verify sampling, recovery and output quality. A controlled trial should record throughput, metal recovery, residue volumes, operating labour and total logistics cost, providing evidence for a commercial decision rather than relying on laboratory results alone.
Identify a representative cable stream, request a technical and assay plan from Ikoi, and bring together an Australian processor, downstream refiner and logistics partner. Build the pilot around verified recovery and responsible residue management, then scale the compact plant only when the commercial case is proven.