Efficient Silver Recovery

Efficient Silver Recovery：

             Efficient Silver Recovery from Waste Film via Centrifugal Electrodeposition

While traditional film usage has declined in the digital era, discarded films remain a

valuable source of recoverable silver. This article details an industrial-grade solution

for extracting silver efficiently using centrifugal electrodeposition technology.

             1. Core Principles of Centrifugal Electrodeposition.Combining rotational

dynamics with electrochemical reduction, this advanced method outperforms

conventional electrolysis through three key mechanisms:

             Kinetic Enhancement: Centrifugal forces (2,000–3,000 rpm) accelerate ion

migration by 4–6.Purity Optimization: Stratified separation prevents impurity codeposition

Energy Efficiency: Pulse power supply (5–15V/50–100A) paired with dynamic rotation cuts energy use by 35%

2. Four-Stage Operational Workflow
Stage 1: Chemical Leaching
Operators immerse waste film in nitric acid (15–30% concentration), triggering double displacement reactions:
AgBr + 2HNO₃ → AgNO₃ + HBr↑
AgCl + 2HNO₃ → AgNO₃ + HCl↑
Maintaining 50–70°C ensures >90% silver halide conversion within 2 hours.
Stage 2: Electrodeposition Initiation
The AgNO₃ solution (80–120g/L Ag⁺ concentration) enters a rotating electrolytic cell. Under DC current (0.5–1.5A/dm² cathode density), silver ions migrate toward the titanium cathode:
Ag⁺ + e⁻ → Ag↓

Stage 3: Centrifugal Enhancement
At 2,500 rpm operation:

Generates 18–25G acceleration, tripling deposition speed vs. static electrolysis

Forms laminar boundary layers, controlling silver crystal size at 20–50μm

Auto-replenishes electrolyte when density drops below 1.2g/cm³

Stage 4: Silver Harvesting
Every 4–6 operational hours:

Retrieve cathode drum post-rotation

Apply ultrasonic vibration (20–40kHz) for non-destructive silver peeling

Collect 99.5% purity silver powder.vido