Plating System. Hexavalent Chromium-free Reduced energy consumption

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1 Hex-A-Gone 1020 Plating System Hex-A-Gone 1020 is a decorative trivalent chromium electroplating system which produces a finish comparable in color to a hexavalent chromium deposit. Hex-A-Gone 1020 offers exceptional throwing power, ease of operation, and good tolerance to metallic impurities. Trivalent chromium plating solutions offer reduced waste treatment costs and less health and environmental concerns than hexavalent chromium solutions. Exceptional throwing power with bright deposits at thicknesses up to 20 microinches (0.5 microns) Environmentally friendly - Contains no carcinogenic hexavalent chromium Higher bath efficiency produces plating rates of 2-3 microinches per minute ( microns/minute) Improved throw compared to hexavalent chrome plating allows for 30-50% increase in rack density Deposit color is similar to hexavalent chromium deposits Hexavalent Chromium-free Reduced energy consumption PAVCO, Inc John Crosland Jr Drive Charlotte, NC Phone: Toll-free: or PAVCO INC ( ) Fax: Order Fax (for orders only)

2 Operating Parameters: Total Chromium: (use High Efficiency for high thickness applications) Hex-A-Gone Salts: Range Optimum 6-13 g/l 9.5 g/l (High Efficiency) 7 g/l (General Purpose) oz/gal g/l 37.3 oz/gal 280 g/l Hex-A-Gone Cr Maintenance: % 12.5% Surface Tension: dynes/cm 30 dynes/cm Cathode Current Density: Anode Current Density: ph: ASF (6-10 ASD) ASF ( ASD) Temperature: F o C ASF (8 ASD) 125 F 52 C Specific Gravity Equipment: Tank: Anodes: Anode Bars: ph meter: Filtration: Rectifier: Temperature Control: Ventilation: Agitation: Metallic Removal: A polypropylene, PVC, or Koroseal lined tank. Inert anodes with special catalytic coatings are used for direct contact with plating solution. Pavco recommends a plastic mesh be put over the anodes to prevent scratching or mechanically damaging the catalytic coating. Contact Pavco representative for sourcing. USE ONLY PAVCO QUALIFIED ANODE SOURCES Use copper anode bars, preferably shielded with plastic. Careful control of ph is critical to the successful operation of Hex-A-Gone A good ph probe and frequent standardization of the meter are necessary. Use 5-15 micron polypropylene filters and activated carbon. Filtration speed should be at least 1 tank turnover per hour. Up to 12 volts, less than 5% ripple A titanium heat exchanger is recommended. Required, check local regulations Air agitation is required for dissolution of salt additions. Air agitation is optional when electroplating. If air is used, it should be light and uniform. Slow mechanical agitation with a moving cathode rod produces the most optimal results. Effective contaminant removal is critical to maintaining consistent deposit color. Continuous contaminant removal is recommended by continuous dummy cell (10% of tank volume) or ion exchange. Consult a Pavco representative for recommendations on dummy cell design or Premier IX Resin ion exchange resin system. 2

3 Bath Maintenance: Hex-A-Gone Cr Maintenance: DecoTri MS: Hex-A-Gone Salts: 1 gal/ amp - hrs. ( mls/1000 amp-hrs(kah)) Rate varies with cathode efficiency. Adjust feed rate based on chrome metal concentration. Continuous, regular additions are required, even during DUMMY ELECTROLYSIS 1 gal/ 25,000 amp - hrs. (150 mls/kah) Based on specific gravity (see Analytical methods) consumed by dragout. Hex-A-Gone Catalyst: 1 gal/10,000-25,000 ( mls/kah) Start at 1 gal per 17,000 AH (220 mls/kah) Hex-A-Gone 1020 Carrier: 1gal/5000 AH (760 mls/kah) CAUTION: Careful, routine monitoring of ph is required for successful operation of Hex-A-Gone DO NOT ALLOW THE ph TO EXCEED 3.8. Bath Makeup per 1000 gallons-3785 liters: Use General Purpose makeup unless otherwise specified by Pavco representatives. 1. Add 800 gallons (3000 liters) of de-ionized water to a clean tank. 2. Heat the water to 130 o F (54 o C). Maintain at this temperature during make up procedure. 3. Add 2335 pounds (1060 kg) of Hex-A-Gone Salts slowly with good agitation. 4. For High Efficiency makeup, (9.5 g/l chrome) add 160 gallons (606 L) of Hex-A-Gone Cr Make up. For General Purpose makeup, (7 g/l chrome) add 120 gallons (454 L) of Hex-A-Gone Cr Make up. 5. After the salts and make-up are thoroughly dissolved and mixed, raise the solution level to 90% of operating volume with de-ionized water. Then lower the ph of the solution to 1.8 with 50% sulfuric acid. Agitate the bath for 12 hours minimum to establish the proper chromium complex. After the 12 hour period, raise the ph over a two hour period to operating range with 45% potassium hydroxide. (low chloride grade). Treat solution with 2 g/l activated carbon powder. Allow to stir for 2 hours then remove with filter. 6. Add 12.4 gallons (46.9L) of Hex-A-Gone 1020 Carrier, 2.5 gallons (9.5L) of Hex-A- Gone Catalyst, 17.5 gallons (66.2L) Hex-A-Gone Whitener, and 2 gallons (7.6L) DecoTri MS. 7. Add D.I. water to the final volume. 8. Electrolyze the bath for a minimum of 2 amp-hours/gallon (0.5 amp-hours/liter) as needed before use. Confirm plating rate and coverage by hull cell before production use. 3

4 Operating Tips: Use routine additions of Hex-A-Gone 1020 Carrier + Hex-A-Gone Catalyst to maintain good coverage, color, and thickness of the chromium deposit. Use routine additions of Hex-A-Gone Cr Maintenance to maintain chromium levels. Hex-A- Gone Cr Make up is normally only needed for new bath make-up or when Hex-A-Gone Complexor levels are low. Higher chromium levels will improve the high current density range but can reduce coverage in low current density areas. Use of waste treatment grade caustic is not recommended. Use caustic with a specification of less than 50 ppm chloride (<.005%) to avoid chloride contamination issues. Chloride accumulation can decrease life of anode coating. Metallic contaminants MUST BE TREATED REGULARLY. Nickel in excess of 50 ppm, zinc in excess of 10 ppm, or iron in excess of 30ppm can reduce the bath efficiency (slow down the rate of deposition) as well as darken the deposit. Best practice is to use Premier Ion Exchange resin. Another option is to electrolyze the solution at 18amps/ft 2 (2 amp/dm 2 ) in a continuous electrowinning cell. Total combined metallic contaminants should be kept under 50 ppm in order to achieve blue color. Carbon filtration is recommended to maintain good color and efficiency. Use 2-4 pounds of granular activated carbon (1-1.5 kg) per 1000 gallons (4000 liters) of solution. Replace the carbon every two weeks. Inspect the anode coating every three months. The anodes will require periodic recoating. Thin anode coating will result in hex chrome formation and poor chromium coverage. Routinely check for hex chrome to confirm proper anode coating and addition rates. Hexavalent chrome formation can be due to poor anode coating, low HAG Carrier, or bath contaminants. Keep the specific gravity below 1.26 for optimal high current density performance. Catalyst levels will reduce gradually during downtime. Monday morning startup typically requires extra HAG Catalyst ( %) to obtain desired plating rate. Hex-A-Gone 1020 Components and Functions: Hex-A-Gone Cr Make-up (HG 106) Provides the chromium salts necessary for a solution. Make-up can be used to replenish chrome if Complexor levels are low. In this case, CR Makeup may be used in place of CR Maintenance. Do not use if Complexor levels are normal. Hex-A-Gone Salts (HG 116) Provides the salts required to operate the system. Hex-A-Gone Salts are depleted when operating the bath. Regular analysis and additions of this product are required. Do not add salts if the specific gravity exceeds 1.24 g/l. 4

5 Hex-A-Gone Cr Maintenance (HG 100) Provides the correct balance of chromium metal and complexors to maintain the bath. Hex-A-Gone Cr Maintenance must be added on an amp-hour basis. Hex-A-Gone 1020 Carrier (HG140) This maintenance additive is fed on amp hour basis to maintain all the brightening and complexing agents in the bath. It is fed in combination with Hex-A-Gone Catalyst. This additive replaced the prior existing 1020 BC Maintenance, use Carrier to improve deposit brightness. DecoTri MS (PPS30553) Reduces surface tension and prevents gas streaks. Improves HCD range. DecoTri MS can be added on an amp-hour basis. It is controlled by surface tension analysis. Hex-A-Gone Whitener (HG 110) Hex-A-Gone Whitener is contained in 1020 Carrier. It helps to maintain the characteristic color of the deposit. Hex-A-Gone Whitener should only be added at the direction of Pavco technical personnel. Hex-A-Gone Catalyst (HG 114) Hex-A-Gone Catalyst controls the deposition rate. Typical addition is %. Extra Catalyst will be needed in presence of zinc contamination. Add 0.1% Hex-A-Gone Catalyst at 20 ppm Zinc. Catalyst must be added on an amp-hour basis. Excess Catalyst can cause hazing. Hex-A-Gone Extender (HG 101) Hex-A-Gone Extender should only be added at the direction of Pavco technical personnel. This additive will improve LCD coverage of the chrome. It will tend to darken the deposit with overuse, so use minimally in 0.1% increments. Hex-A-Gone Complexor (HG 115) Hex-A-Gone Complexor should only be added at the direction of Pavco technical personnel. Low Complexor can lead to poor throwing power and rapid formation of hexavalent chrome. Low Complexor is indicated by a green solution color. High Complexor will cause reduced efficiency. 5

6 Analytical Procedures: Hex-A-Gone Salts by titration Reagents 1. Mannitol 2. 1N sodium hydroxide Procedure 1. Pipette a 5 ml bath sample into a 150 ml beaker 2. Add 20 mls de-ionized water. 3. Add a Teflon-coated magnetic stir bar & mix solution on stir plate throughout the analysis. 4. Using a ph meter, adjust ph solution to using either 1 N sodium hydroxide or 1 N sulfuric acid. Record final ph. 5. Add 10 g Mannitol (Excess Mannitol is necessary at all times). 6. Slowly titrate the solution with 1N sodium hydroxide until the recorded ph is reached. Add additional Mannitol (2g) at the end. If ph drops continue titrating. 7. If ph does not change, endpoint has been reached. Calculation: Hex-A-Gone Salts (g/l) = [ Mls titrated (NaOH) X Normality (NaOH) x 49 ] Hex-A-Gone Salts by Specific Gravity: Salt concentration can also be determined by Specific Gravity. Weigh 100 mls of plating solution on a gram scale using a 100 ml volumetric flask. Be sure that flask is dry and determine tare weight of empty flash. Subtract tare weight from total weight. Scale used must be accurate to +/- 0.1 grams. Specific gravity in g/ml = weight in grams / 100 ml Use the chart below that is closest to your operating chrome concentration. If your Hex-A-Gone Salt concentration by specific gravity does not match your Hex-A-Gone Salt by titration within 25 g/l, consult a Pavco representative. oz/gal Hex-A-Gone Salts = g/l Hex-A-Gone Salts/7.5 CAUTION: DO NOT ADD SALTS IF THE SPECIFIC GRAVITY EXCEEDS Consult your Pavco Representative if you Salts by titration are low and your specific gravity is high. 5 g/l Chrome SpG (g/ml) SALTS (g/l)

7 7 g/l Chrome SpG (g/ml) SALTS (g/l) g/l Chrome SpG (g/ml) SALTS (g/l)

8 Analytical Procedures: Chrome Metal Reagents 1. Sodium hydroxide 2. 30% hydrogen peroxide 3. 1:1 sulfuric acid 4. 10% potassium iodide 5. Starch solution N sodium thiosulfate Procedure 1. Pipette a 5 ml bath sample into a 250 ml Erlenmeyer flask 2. Add 100 mls de-ionized water. 3. Add 2 grams of sodium hydroxide to the flask and swirl to dissolve 4. Add 2 mls of 30% hydrogen peroxide. 5. Boil the solution until all the peroxide is gone, at least 30 minutes. 6. Cool the solution to room temperature. 7. Add 10 mls of 1:1 sulfuric acid 8. Add 5 mls of 10% potassium iodide. 9. Titrate with 0.1 N sodium thiosulfate to a straw color. 10. Add 2 mls of starch indicator. 11. Continue the titration to the absence of a blue color which persists for 30 seconds. Calculation: g/l Total Cr = (ml. of Na 2S 2O 3) (N of Na 2S 2O 3)(17.3) (mls of sample) % Hex-A-Gone Cr Maintenance = g/l total Cr x 1.25 Hex-A-Gone Whitener, Hex-A-Gone Complexor, surface tension, Metallic contaminants & chloride contamination Submit regular samples to your Pavco representative for routine monitoring of these bath components. Monitoring these components and adjusting as needed is critical to the long term consistency of the Hex-A-Gone 1020 process. Initial testing upon installation is recommended weekly. Thereafter, monthly samples are usually sufficient. Containment Limits: Contaminant Upper limits Effect Copper <5 ppm Poor color, poor efficiency Nickel <50 ppm Poor color, poor efficiency, streaks Zinc <10 ppm Poor efficiency, haze in deposit Iron <30 ppm Darkens deposit Chloride <500 ppm Degrades anode coating Fluoride <50 ppm Degrades anodes 8

9 Analytical Procedures: Hexavalent Chrome Test for Hex-A-Gone 1020 Trivalent Chrome Solution (Qualitative) Summary This procedure determines whether hexavalent chrome is being produced at the anodes. This helps determine anode quality as well as proper additive concentrations in solution. Equipment required 250 ml Erlenmeyer flask 1 ml pipette 50 ml graduated cylinder Reagents Diphenylcarbazide, 0.5% in acetone Sulfuric acid, 50% Distilled or Deionized water (DI) Procedure 1. Add 90 mls DI water to a 250 ml Erlenmeyer flask. 2. Add 10 mls Sulfuric acid, 50%, with a graduated cylinder. 3. Add 1 ml diphenyl carbazide indicator solution. Observe for pink color. If solution is pink, discard and wash all glassware before returning to step If solution is not pink after Step 3, pipette 1 ml of trivalent chrome solution into the flask. 5. Observe for the development of a pink color. Pink indicates presence of hexavalent chrome. A barely distinguishable pink color indicates ppm hexavalent chrome Opaque pink/red indicates in excess of 500 ppm hexavalent chrome Notes: Take care not to contaminate diphenylcarbazide indicator solution with chromium solution. Discard the indicator if contaminated. A colorless solution after step 3 demonstrates clean indicator, glassware and reagents. Test the trivalent chrome plating bath immediately after sampling the bath. Any hexavalent chrome generated at the anodes will rapidly react with bath additives and give false negative results if sample is allowed to sit idle. Check the bath after 1, 4, and 8 hrs of production. Positive hex chrome tests can indicate a defective anode coating. Consult your Pavco representative. Pink color in 1-4 hours will require corrective action. If hexavalent chrome is present, check Hex-A-Gone Complexor levels. Adjust as needed in 2 g/l increments. Check feed rate for Hex-A-Gone Carrier and Catalyst to confirm optimum feed rate. Check contact on anodes and inspect for damaged coating. Check anode current density and increase anode area. Send anodes to Pavco lab for coating thickness testing. Send anodes out for recoating. 9

10 Analytical Procedures: Hull cell analysis Equipment 10 Amp rectifier Heated hull cell Polished brass panels Stainless steel beaker Hot plate Stainless steel tongs Alkaline electroclean (Clean-R-2002) 8 opg (60 g/l) 5% Sulfuric acid in 500 ml glass beaker Thickness tester, XRF or Kocour /equivalent destructive thickness tester 1) Heat cleaner in a stainless steel beaker to 140F. (60 C) Attach anode lead (+) from rectifier to stainless steel beaker. Use stainless tongs connected to the cathode lead (-) to clean a bright brass panel cathodically at 10 amps for seconds. Rinse in clean water. 2) Immerse in 5% sulfuric acid for 5-10 seconds, agitate. 3) Rinse. Ensure panel has a water break free appearance. If not, repeat cleaning process or change cleaner 4) Place panel in preheated hull cell. Solution must be maintained at actual bath operating temperature in order to be representative of actual plating conditions 5) Run a 5 amp, 3 minute hull cell panel 6) Measure thickness at 1.7 cm, 3.9 cm, 6.1 cm, and 7.9 cm from left edge of panel. If using x-ray testing, ensure machine is calibrated for chrome over brass. If it is not calibrated for chrome over brass, then panel must be nickel plated before running the chrome hull cell. Destructive tester usually require nickel plated panels. Note: Bright brass panels are preferred over dull panels as they allow easy observation for chrome deposit variations such as dullness. Typical Deposit Thickness: Chrome (microinches) HCD 1.7 cm 3.9 cm 6.1 cm LCD 7.9 cm (microns) ASF 18 ASD 90 ASF 10 ASD 45 ASF 5 ASD 18 ASF 2 ASD 10

11 Trouble Shooting Chart: Problem Cause Solution HCD Skip plate Low wetting agent Add up to 0.3% DecoTri MS ph not in range Low salts, low chrome Low temperature Low Hex-A-Gone Catalyst Adjust ph with low chloride potassium hydroxide or sulfuric acid Check specific gravity, Hex-A-Gone Salts and chrome. Adjust as needed. Check and adjust Add 0.05% increments Hex-A-Gone Catalyst Thin or no chromium deposit Poor coverage w/ clean LCD Dark or streaky LCD or overall streaky or dark deposit Low chemistry Low Catalyst ph was too high or bath is under used. Bath needs low ph treatment. Metallic contamination Hexavalent chrome contamination Temperature out of range Low chrome Metal Low Hex-A-Gone Salts Low Hex-A-Gone Catalyst Low Hex-A-Gone Complexor (Green solution color) Organic contamination Metallic contamination Check chrome, spg, Hex-A-Gone Salts, ph and adjust as needed Add 0.05% increments Hex-A-Gone Catalyst Heat bath to 120 o F (49 o C). Lower the ph to 2 with sulfuric acid and maintain for 12 hours. Slowly raise the ph to with liquid KOH. Electrolyze for 2 amp hours/gal Check for copper, nickel, iron, zinc. Regenerate or replace resin or electrolyze the bath at 18 ASF (1.9 ASD) Run hex chrome test. Check anode coatings. Treat with Sodium Metabisulfite until hex test is negative. Add in a ratio of 3 parts Sodium Metabisulfite:1Part Hexavalent Chromium (can typically be added in 0.05 g/l increments). See section below on hex chrome contamination. Adjust temperature to F (49-60 o C) Analyze chrome and adjust to range with Hex-A-Gone CR Maintenance Analyze and adjust the Hex-A-Gone Salts concentration Add 0.05% increments or Hex-A-Gone Catalyst Send sample to Pavco Laboratory for analysis. Add in 2 g/l increments Filter continuously through activated carbon. Replenish wetter after treatment with up to 0.3% DecoTri MS Check for copper, nickel, iron, zinc. Regenerate or replace resin or electrolyze the bath at 18 ASF (2ASD) to remove these metals. 11

12 Thin white bands, dull or blue deposit Thin white bands, dull or blue deposit White haze in LCD (strips in 10% sulfuric) Constant hex chrome issues Short anode life (less than 2-3 years) Excess Hex-A-Gone Catalyst Low Hex-A-Gone 1020 Carrier Electrolyze or withhold adds of Hex-A-Gone Catalyst. If this is not sufficient, add 0.03% increments of hydrogen peroxide until haze is eliminated. Allow 20 minutes between additions of peroxide Check Carrier level and adjust to 1-1.5%. Check hull cell thickness and add 0.3% increments of Carrier if thickness is above normal. Zinc contamination Check for dropped parts, electrolyze at 5-10 ASF or regenerate IX resin. Increased Hex-A- Gone Catalyst can help improve efficiency in the presence of zinc. (0.1% for 20 ppm) High anode current density Degraded/ineffective anode coating Low Hex-A-Gone Complexor levels Improper addition rates Increase number of anodes Send anode to Pavco for thickness analysis. Recoat anodes. Submit sample to Pavco lab and adjust as needed Check addition rates for Carrier, Catalyst and Hex-A-Gone CR Maintenance. Adjust as needed. Increase addition rate of Carrier and Catalyst if needed. High zinc contamination Analyze for zinc. Pump tank and inspect bottom for parts. Dummy plate to remove zinc or regenerate ion exchange resin to improve zinc removal capacity. Add extra Hex-A-Gone Catalyst (0.05% increments) until thickness returns Thin or poorly adherent coating High fluoride (>50 ppm) High chloride (>500 ppm) Recoat anodes using qualified source Eliminate source. Do not use fluoridated acid salts in acid dips prior to Hex-A-Gone 1020 Improve rinsing after nickel. Use DI water for makeup water. Do not use softened water. Do not use hydrochloric acid to regenerate resins 12

13 Waste Treatment: Dispose of the concentrate or solutions thereof according to local waste treatment regulations. Safety: Handling Pavco mandates that the following safety equipment be used when handling chemicals in an electroplating environment: safety glasses, face shield, plastic or rubber apron, rubber gloves and safety shoes. Chemicals should only be handled by trained and experienced personnel. Storage Store Pavco products in a clean, well ventilated room which temperature remains above 45 F (7 C). Pavco products should remain in their original container with the lid or cap tightened. Drum pumps or pails must be clean prior to dispensing Pavco products to prevent contamination. If Hex-A- Gone 1020 freezes during shipment or storage, warm the product to and mix it well before use. Emergency Procedures Refer to the MSDS for detailed emergency procedures. Eye Contact Seek immediate medical attention. Flush the eyes with water for 15 m minutes. Skin Contact Remove all contaminated clothing. Wash the skin with soap and water. Seek medical attention. Inhalation Remove the person to an area with fresh air. Seek medical attention if necessary. Ingestion Seek immediate medical attention. Spill- Dike the area to contain the spill. Refer to the MSDS for clean-up. Notify the proper authorities if required. *NOTE: Refer to the MSDS for detailed emergency medical procedures. Product Description & Shipping: Hex-A-Gone Salts (HG 116) is a white powder and is available in 100# containers. Hex-A-Gone Complexor (HG115) is a white powder is available in 40# containers. Hex-A-Gone BC Make-up (HG 108) is a pale yellow liquid with a specific gravity between 1.0 and 1.3 with a ph greater than 12 Hex-A-Gone CR Make-up (HG 106) is a dark blue green liquid with a specific gravity between 1.1 and 1.3 with a ph less than 3 Hex-A-Gone CR Maintenance (HG 100) is a dark blue green liquid with a specific gravity between 1.2 and 1.3 with a ph less than 3 DecoTri -MS (PPS-30553) is a white slightly turbid liquid with a specific gravity between and with a ph greater than 3.0. Hex-A-Gone Whitener (HG110) is a colorless liquid with a specific gravity between 1.0 and 1.1 and a ph less than 9. Hex-A-Gone Catalyst (HG114) is a pale yellow to slight pinkish liquid with a specific gravity between 0.90 and 1.04 and a ph greater than 12. Hex-A-Gone Extender (HG101) is a green liquid with a specific gravity between 1.0 and 1.1 and a ph less than 3.0. Hex-A-Gone 1020 Carrier (HG140) is a clear liquid with a specific gravity between 1.05 and 1.15 with a ph greater than 12. All liquid Hex-A-Gone products are available in 5 gallon containers and 55 gallon drums. Revision Date: 7/21/17 WARRANTY AND DISCLAIMER Technical information and recommendations contained herein are believed to be reliable, however, the accuracy or completeness thereof is not guaranteed. No statement or recommendation shall constitute a representation unless set forth in an agreement in writing by the seller and manufacturer. NO WARRANTY OR MERCHANTABILITY OR WARRANTY OF FITNESS FOR A PARTICULAR PURPOSE IS MADE. The following warranty is made in lieu of any other warranties, express, implied, or statutory. Products are warranted to be free from defects on material and workmanship at the time sold. The sole obligation of the seller and manufacturer under this warranty shall be to replace any product defective at the time sold. Under no circumstances shall the manufacturer or seller be liable for any loss, damage, expense, direct or consequential, arising out of the use of or inability to use the product. Materials shall not be returned to the seller or manufacturer without express written permission. No information or suggestions given by us shall be deemed to be a recommendation to use any product in conflict with any existing patent rights. 13