Gold Stripping Machine

— Gold Stripping Machine – Gold recovery rate of up to 99%

The Gold Stripping Machine is a purpose-built chemical stripping line that removes the gold plating layer from gold-plated materials recovered from obsolete and junked electronic products. It is currently one of the most efficient gold extraction methods available for plated scrap: the system achieves a gold recovery rate of up to 99%, and the recovered crude gold powder can be further refined to high-purity gold bars (99.95%–99.99%) on a standard refining line.

This gold stripping system is an essential front-end device. When used in conjunction with an automated component dismantling machine and a precious metal refining production line, it forms a complete gold recycling chain, from waste electronic products to marketable gold products.

Product Overview

The Gold Stripping System is a purpose-built chemical stripping line that removes the gold plating layer from gold-plated materials recovered from obsolete and junked electronic products. It is currently one of the most efficient gold extraction methods available for plated scrap: the system achieves a gold recovery rate of up to 99%, and the recovered crude gold powder can be further refined to high-purity gold bars (99.95%–99.99%) on a standard refining line.

The system uses a patented, cyanide-free stripping agent that dissolves only the surface gold — lead, nickel, iron, tin and other metals in the substrate remain untouched. This selectivity is the core advantage over whole-part dissolution: you recover the gold without destroying the base material, and without handling cyanide.

The Gold Stripping System is the essential front-end equipment for e-waste recyclers, PCB processors, electroplating shops and precious metal refiners handling gold-plated scrap. Combined with an automatic component dismantling machine and a refining line, it forms a complete gold-recovery train from scrap electronics to sellable gold.

Recovery Value Analysis

1. Gold Price Reference

Gold (Au) spot: ~USD 4,450/troy oz ≈ USD 143.1/gram (Kitco, 20 Aug 2026)

2. How Much Gold Is in Plated E-waste?

Gold density: 19.3 g/cm³, giving the physical conversion:

1 µm of gold plating on 1 m² of surface = 19.3 grams of gold

Typical plating thicknesses found in e-waste (industry ranges — verify with XRF on your material):

PCB gold fingers / edge connectors: 0.3–1.5 µm hard gold
CPU and IC lead-frame plating: 0.3–1.0 µm
Connector contacts and relays: 0.5–2.5 µm
Decorative/hobby plating: 0.1–0.5 µm

Worked example (assumption-based illustration): 100 kg of gold-finger scrap averaging 0.8 µm over an estimated 25 m² total surface holds 25 × 19.3 × 0.8 = 386 g of gold ≈ USD 55,240 at USD 143.1/g. At the system’s 99% recovery rate, ~USD 54,700 is recoverable per batch before refining cost. Actual results depend on measured thickness, area, gold price and scrap sourcing price — we recommend a free XRF analysis of your material before valuing any deal.

3. Recovery & Separation Performance

Gold recovery rate: up to 99% (manufacturer-tested)
Gold separation rate: 99%, with high purity of the recovered gold powder
Stripping speed: 0.5–2 mm/min average (manufacturer data)
Selectivity: no dissolution of lead, nickel, iron or tin substrate metals (patented stripping agent)
Substrate preservation: no stain or attack on nickel or tin layers

4. Secondary Revenue

Because the stripping agent does not attack the substrate, the stripped base material remains a clean, saleable scrap stream (copper-based boards, nickel-plated parts). This by-product revenue reduces net operating cost and improves overall project economics.

Applicable Materials

The Gold Stripping System applies to a wide range of gold-plated scraps generated in daily life and industry:

Consumer electronics (obsolete & junked)

Waste cellphone circuit boards and mobile phone mainboards
Computer CPUs and motherboards
Memory modules (RAM) gold fingers
VCDs, DVDs, TV circuit boards, game consoles
Fax machines, telephone sets and other old domestic appliances
Remote controls, chargers and small appliance boards

Plating & manufacturing industry off-cuts

Electroplating factory leftovers, rejects and rack scrap
Electronic components manufacturing off-cuts (lead frames, contacts)
Printing house and photosensitive materials plant scrap
Gold-plated connectors, switches, relays and terminals

Jewellery & accessories

Gold-plated jewellery rejects and overplated work
Plated watch parts, chains and fashion accessories

Key material pre-conditions

Material must be gold-plated (surface layer), not gold alloy (alloys require refining, not stripping)
Sort by substrate type before processing; remove gross contamination and non-plated scrap to maximise bath efficiency
Solder-coated parts should be separated — solder interferes with stripping solution life

Gold Stripping System Process Flow

The system follows a proven four-stage chemical process (patented stripping agent):

Stage 1 — Stripping solution preparation

The cyanide-free stripping agent is dispensed and mixed with water in the stripping tank to the specified working concentration. Solution temperature and volume are set per the batch size and material type.

Stage 2 — Immersion stripping (gold dissolution)

Gold-plated materials are loaded into the stripping solution (baskets or racks). The surface gold dissolves into the solution as a stable gold complex, while no other metals — lead, nickel, iron, tin — dissolve (patented selectivity):

Gold layer: Au (surface) + stripping agent → gold complex (solution)
Substrate: Ni / Sn / Cu base remains intact

Stripping proceeds at an average rate of 0.5–2 mm/min (manufacturer data). The endpoint is visible: the golden surface colour disappears, revealing the intact base metal. Selective stripping allows alternative/sectional stripping where only part of a part is plated.

Stage 3 — Filtration

The loaded solution is filtered to remove insoluble impurities (dust, debris, base-metal particles) before gold recovery, protecting the quality of the final gold powder.

Stage 4 — Reduction & gold powder recovery

A reduction powder is added to the solution; the dissolved gold is reduced and precipitates as black crude gold powder:

Gold complex (solution) + reduction powder → Au↓ (black powder) + spent liquor

The black powder settles; the supernatant is decanted; the crude gold powder is collected, washed with hot deionised water and dried at 110–120°C.

Stage 5 — Further refining (recommended)

The crude gold powder (typically 90–98% Au) is fed to a gold refining machine — aqua regia, electrolytic or chlorination route — to produce 99.95%–99.99% gold bars for maximum market value. We supply the complete refining line to match.

Stage 6 — Spent solution management

The spent liquor is verified gold-free (SnCl₂ test — no purple colour) before treatment. The stripping agent can be regenerated/replenished for continued bath life; final barren liquor is treated under the hazardous waste protocol of the site.

Main Equipment Components

A complete Gold Stripping System comprises:

Stripping section

PP/HDPE stripping tank with lid and vapour extraction (sizes 100–2,000 L)
Solution dispensing and mixing unit (patented stripping agent)
Heating system with thermostat (40–60°C, ± 2°C) where required
Agitation / solution circulation pump with sparger
Perforated PP loading baskets or racks

Filtration section

Corrosion-resistant filter press or cartridge filtration unit for solution clarification

Gold recovery section

Reduction tank with slow-speed stirrer
Reduction powder dosing system
Settling cone / thickener for black gold powder collection
Peristaltic pump for solution transfer

Washing & drying section

Washing tank with DI water supply and conductivity meter
Drying oven (110–120°C, stainless steel interior)

Safety & environmental

Fume extraction hood and scrubber (water/condensation type for the cyanide-free chemistry)
Emergency shower and eyewash
Chemical storage cabinet (sealed, ventilated)

Analytical & QC

Handheld XRF (plating thickness, residual gold verification)
SnCl₂ endpoint test kit
Analytical balance

Technical Specifications (Standard Range)

Tank capacity: 100 L / 300 L / 500 L / 1,000 L / 2,000 L (custom on request)
Batch loading: 20–300 kg plated scrap per cycle
Stripping time: 20 min – 2 h per batch (thickness-dependent)
Stripping speed: 0.5–2 mm/min average (manufacturer data)
Gold recovery rate: up to 99%
Gold separation rate: 99%, high gold purity
Stripping agent: cyanide-free, non-toxic, patented formula; no attack on nickel/tin layers
Operating temperature: 20–60°C (ambient to heated)
Wetted materials: PP/HDPE; titanium heater sheaths
Power: 2–10 kW (circulation + optional heating)
Footprint: 1.5 m × 1.0 m (100 L) to 4.5 m × 2.0 m (2,000 L)
Automation: manual / semi-automatic (timer + temperature) / PLC full-automatic

Features & Advantages

Up to 99% gold recovery — the highest-efficiency stripping chemistry for gold-plated e-waste
Patented cyanide-free stripping agent — contains no cyanide and no poisonous substances; safe to operate, compliant with modern environmental regulation in Western markets
No stain to nickel or tin layers — substrate metals (Ni, Sn, Pb, Fe) are not dissolved; the base material retains its value as clean scrap
Fast stripping speed — average 0.5–2 mm/min; short batch cycles and high throughput per tank
High stripping accuracy — gold can be stripped selectively, section by section, where partial plating exists
High separation efficiency — 99% separation rate with high purity of recovered gold powder
Simple four-stage process — solution → immersion → filtration → reduction; one operator per line, no specialised chemical skills required
Full support line available — automatic component dismantling machines and gold refining machines complete the value chain from whole e-waste to 99.99% bars
Pre-delivery testing guarantee — every machine is test-run with the customer’s actual material under simulated production conditions before delivery; customers are invited to attend the final test
Proven worldwide — installations including a Hungarian customer site operating in Europe (EU environmental compliance)

Key Notes & Cautions

Material preparation

Sort and assay before pricing: verify plating thickness with XRF — gold value follows the physical conversion 19.3 g/m² per µm; never price plated scrap by visual estimate
Separate solder-coated parts and gold alloy items — they are not suitable for stripping
Remove gross contamination and batteries; check for non-plated steel housings mixed in the batch

Process operation

Prepare the stripping solution to the specified concentration; do not over-concentrate — faster is not better and shortens bath life
Monitor stripping endpoint visually and by periodic XRF spot checks; over-immersion wastes agent and risks substrate attack
Filter the loaded solution before reduction — unfiltered solids contaminate the gold powder and lower its purity
Verify reduction completion with the SnCl₂ endpoint test (no purple colour) before decanting the spent liquor
Keep a batch ledger: input XRF value vs recovered powder vs losses — target accounting accuracy within ±2%

Safety & compliance

Although the agent is cyanide-free, handle all chemicals with gloves, goggles and apron; the room needs adequate ventilation and an eyewash/shower
Spent liquor and wash water are hazardous waste — treat and dispose under your hazardous waste permit; never discharge gold-bearing solution
Confirm local environmental regulations; the cyanide-free chemistry simplifies compliance compared to traditional cyanide stripping

Equipment maintenance

PP tanks: do not exceed 60°C continuously; inspect welds and fittings for leaks
Titanium heaters: never run dry; descale regularly
Filter cloths and cartridges: inspect for breakthrough; replace on schedule
Calibrate XRF and balances quarterly

FAQ

Q1: What is the difference between gold stripping and gold refining?
Stripping strips the gold plating layer from base-metal substrates, producing gold-rich solution and crude gold powder — it concentrates value. Refining purifies that powder (or any gold material) to 99.99% bars. Stripping is the front-end; refining is the back-end. Most e-waste recyclers run both.

Q2: Is the stripping agent safe? Does it contain cyanide?
No cyanide and no poisonous substances — it is a patented cyanide-free formulation. This is a decisive advantage over traditional cyanide+oxidant stripping, simplifying safety management and environmental compliance in markets with strict chemical regulation.

Q3: Will the stripping solution damage the nickel or tin layer?
No. The patented agent dissolves only surface gold; lead, nickel, iron and tin remain undissolved, and there is no staining of nickel or tin layers. The stripped substrate can be sold as clean scrap.

Q4: How fast is the stripping process?
The average stripping speed is 0.5–2 mm/min (manufacturer data). A typical batch completes in 20 minutes to 2 hours depending on plating thickness, temperature and agitation.

Q5: How much gold can I recover from my plated scrap?
Measure plating thickness and surface area: 1 µm on 1 m² = 19.3 g of gold. At 99% recovery, 25 m² of 0.8 µm fingers yields ~382 g gold (≈ USD 54,700 at current prices, before refining). Send us a sample — we run a free XRF analysis and trial stripping, returning a yield report per kilogram of your material.

Q6: What is the minimum batch size?
Bench/trial units handle a few kilograms; production systems start at 100 L tanks (20 kg/batch) and scale to 2,000 L (300 kg/batch).

Q7: Can the stripped substrate still be sold?
Yes — substrate preservation is a core advantage. Clean copper-based boards and nickel parts are sold as scrap, generating by-product revenue that typically covers operating costs.

Q8: Do you test the equipment before delivery?
Yes — every machine is test-run under simulated real production conditions using your actual material before delivery, verifying line performance and output. Customers are sincerely invited to attend the final test at the factory.

Q9: What after-sales support do you provide?
Installation and commissioning supervision, operator training (process + safety), SOP manuals, spare parts, remote video support and process optimisation visits. A 12-month equipment warranty is standard.