Troubleshooting Cyanidezinc

Zinc Brightener 111B - Zinc Brightener 1565B: น้ำยาชุบซิงค์ไซยาไนด์ 111B - น้ำยาชุบซิงค์ไซยาไนด์ 1565B

Zinc Brightener 111B

Zinc Brightener 111B is a highly effective additive for cyanide zinc plating solutions, formulated to deliver excellent protection.

Key Advantages:

• Low Current Density Areas: Remains scratch-free even with excessive brightener addition.

• Low Organic Content: Provides high flexibility and suitability for post-plating maintenance.

Specifications:

• High Gloss: Achieves a high gloss across a wide current density range.

• Cost-Efficient: Reduces usage costs when considering the longevity of the brightener.

• Temperature Resistance: Withstands plating solution temperatures up to 50°C.

• Versatile Use: Suitable for both deep recesses in hanging tanks and high-volume rolling tanks.

• Current Density: Effective for both high and low current densities.

• Chromate Compatibility: Plated zinc surfaces respond well to all types of chromates.

Usage Instructions:

• Recommended Solution Composition for Zinc Plating:

  • Zinc: 25 - 35 g/L

  • Sodium Cyanide: 60 - 90 g/L

  • Sodium Hydroxide: 75 g/L

• Brightener Addition: 0.5 – 2 cc/L

Preparation of Plating Solution:

1. Clean the plating tank or mixing vessel thoroughly, then fill half of the tank with clean water.

2. Wash with a 2% sodium hydroxide solution for at least 12 hours, then rinse with clean water.

3. Gradually add the calculated amounts of chemicals while stirring until completely dissolved, then cool.

4. Add Zinc Purifier (PURISOL) at 4 cc/L and stir well. Allow to settle overnight.

5. Filter the solution, adjust to the desired level, and gradually add Zinc Brightener 111B, stirring thoroughly.

Maintenance:

• Initial Addition: 1 liter of Zinc Brightener 111B per 1,000 liters of cyanide zinc plating solution.

• Adjustment: Add 1 liter of Zinc Brightener 111B per 6,000 – 8,000 ampere-hours.

Notes:

• The exact amount required for preparation and maintenance depends on solution composition, temperature, current density, desired brightness, contamination levels, and plating type (hanging or rolling). Frequent small additions are recommended for maintenance.

Zinc Brightener 1565B

Zinc Brightener 1565B is an additive used in cyanide zinc plating solutions. It is suitable for medium- and low-concentration zinc plating baths, whether for barrel plating or rack plating processes. This brightener helps produce a high and consistent gloss on the plated surface, from high-current density areas to low-current density areas. The product offers cost-effectiveness in terms of usage over its lifespan. It can withstand bath temperatures of up to 50°C, and the zinc-plated surface is fully compatible with all types of chromate conversion coatings. 

Recommended Solution Composition:

• Zinc: 15 - 20 g/L

• Sodium Cyanide: 38 - 50 g/L

• Sodium Hydroxide: 75 g/L

• Brightener Addition: 0.5 – 2 cc/L

Maintenance:

• Initial Addition: 1 liter of Zinc Brightener 1565B per 1,000 liters of cyanide zinc plating solution.

• Adjustment: Add 1 liter of Zinc Brightener 1565B per 6,000 – 8,000 ampere-hours.

Iron Removal Chemical for Zinc Plating Solutions

Potassium Permanganate (KMnO4), also known as "dark purple," is used to remove iron from zinc plating solutions, as iron accumulation can cause surface defects or discoloration after chromating.

Usage Instructions:

• Dosage: 150 - 250 grams per 1,000 liters of plating solution.

Iron Removal Procedure:

1. Remove the plating solution from the tank and set it aside.

2. Weigh the appropriate amount of potassium permanganate based on the solution volume.

   • Example: For 1,000 liters of solution, use 0.15 - 0.25 kg of potassium permanganate.

3. Dissolve the chemical in a small amount of the solution, then mix it back into the main batch.

4. Agitate continuously for 2–3 hours to ensure complete reaction.

5. Let it settle overnight to allow the precipitate to settle at the bottom.

6. Carefully siphon off the clear liquid from the top and discard the sediment.

7. Filter the solution to ensure clarity.

8. Add any missing chemicals and brighteners.

9. Resume plating operations.

Note: Potassium permanganate can also absorb brightener, so add brightener after filtering.

Zinc Purifier (PURISOL): An excellent cleaning agent for removing metal contaminants. Adjust addition based on the acetone test color, indicating excess PURISOL.

Troubleshooting Cyanide Zinc Plating Issues

1. Overall Dullness After Plating:

   • Low Brightener: Add 0.5-1 cc/L.

   • High Temperature: Lower temperature to 30°C.

   • Low Temperature: Increase temperature to 30°C.

   • Organic Contaminants: Filter with potassium permanganate 120-240 g/1000L.

2. Burnt or Dull Areas at High Current:

   • Contaminants: Add cold brightener 5-10 cc/L (diluted).

   • Low Brightener: Add 1 - 2 cc/L.

   • Low Temperature: Increase to 30°C.

3. Striped or Dull Areas at Medium Current:

   • Improper Brightener Levels: Pause brightener addition.

   • Filter: Use potassium permanganate 120-240 g/1000L.

4. Dark Spots at Low Current:

   • High Temperature: Lower to 30°C.

   • Low Cyanide-Zinc Ratio: Add sodium cyanide to achieve a ratio of 2.75-3.0 times zinc.

   • Deep Recesses: Add recess catalyst to the brightener.

5. Darkening After Chromating:

   • Metal Contaminants: Filter with zinc dust 120 g/1000L for contaminants >10 ppm.

6. Poor Adhesion or Incomplete Plating:

   • Low Cyanide-Zinc Ratio: Add sodium cyanide to achieve a ratio of 2.75-3.0 times zinc.

   • High Temperature: Lower to 30°C.

   • Low Sodium Hydroxide: Add to 75 g/L.

   • High Sodium Carbonate: Lower temperature and dilute solution by 10% to 25%.

7. Blistering or Peeling Plating:

   • Chromium Contaminants: Filter with sodium bisulfate 30 g/1000L for >15 ppm chromium.

   • High Sodium Carbonate: Lower temperature and dilute solution by 10% to 25%.

   • Excess Brightener: Filter with potassium permanganate 120-240 g/1000L.

   • Inadequate Cleaning: Review and improve cleaning processes.

8. Slow or Incomplete Plating:

   • High Cyanide-Zinc Ratio: Add zinc oxide to achieve a ratio of 2.75-3.0 times zinc.

   • Low Temperature: Increase to 30°C.

   • Low Sodium Hydroxide: Add to 75 g/L.

   • High Sodium Carbonate: Lower temperature and dilute solution by 10% to 25%.

9. Poor Electrical Conductivity:

   • Low Sodium Hydroxide: Add to 75 g/L.

   • Low Temperature: Increase to 30°C.

10. Strong Ammonia Odor:

    • Use More Zinc Plates: Reduce the use of iron plates and increase zinc anodes.

    • Odor Neutralizer: Add a suitable zinc odor neutralizer.

This guide provides detailed instructions and solutions for maintaining and troubleshooting cyanide zinc plating solutions to ensure optimal performance and quality.