Gold Recovery from Laptop Hard Drives via Aqua Regia: Process and Economics
A laptop hard drive contains roughly $1 worth of recoverable gold (~0.006g per drive at 2026 prices). The recovery process involves disassembly, chip removal via heat gun, incineration, grinding, dissolving base metals in nitric acid, then dissolving gold in aqua regia (HCl + HNO₃), neutralizing with sulfamic acid, and precipitating with SMB. Effective hourly rate: ~$22/hr processing 80 drives. The simpler alternative — selling whole drives to a board-sort company — yields ~$0.17/drive.
A laptop hard drive contains approximately 0.006 grams of recoverable gold, worth roughly $0.98 at February 2026 gold prices (~$158/gram). The gold is found in plated connector pins and thin layers on IC chips on the drive's PCB. ## The Recovery Process **Disassembly:** Remove the PCB from the drive housing (Torx screws). Remove IC chips from the PCB using a heat gun at ~350°C to melt solder. Pull gold-plated connector pins. **Chip processing:** Incinerate IC chips in a high-temperature environment (wood stove or kiln) to burn away epoxy packaging, leaving behind ceramic and metal residue. Grind to fine powder. **Base metal removal:** Dissolve the powder in nitric acid (HNO₃), which dissolves copper, tin, and other base metals but not gold. Filter and rinse. The remaining solid contains gold. **Gold dissolution:** Dissolve the gold residue in aqua regia — a mixture of hydrochloric acid (HCl) and nitric acid (HNO₃) in a 3:1 ratio. This is the only common acid mixture capable of dissolving gold. The solution turns yellow-green when gold is in solution. **Neutralization:** Add sulfamic acid to neutralize excess nitric acid in the solution. This is necessary because excess nitric acid will prevent gold precipitation. **Precipitation:** Add sodium metabisulfite (SMB) to the solution. SMB reduces dissolved gold ions back to metallic gold, which settles as a fine brown/black powder. Filter, rinse, and melt the powder to produce a gold bead. ## Economics Processing 80 laptop hard drives yielded approximately 0.48g of gold (~$76 at $158/g). Total processing time was roughly 3.5 hours of active work, giving an effective hourly rate of approximately $22/hour. The far simpler alternative: sell complete drives to a board-sort company for ~$0.17 per drive ($13.60 for 80 drives, no chemistry required). ## Safety Aqua regia and nitric acid produce toxic fumes (nitrogen dioxide, chlorine gas). All acid work must be performed outdoors or under a fume hood. Proper PPE: chemical-resistant gloves, safety goggles, acid-resistant apron. Acid waste must be neutralized (sodium bicarbonate) before disposal.