Prior to making up CLZ-219 zinc plating solution, the processing tank must be cleaned and rinsed thoroughly. In addition, the tank should be leached for a minimum of 24 hours. (See Leaching).

1. Add 50 litres of warm water, 54 °C to the 100 litres tank.
2. Add 8 litres of CZ 515 A with stirring.
3. Add 4.5 kg's. of ammonium chloride.
4. Add 18 kg's. of potassium chloride and stir until almost dissolved.
5. Check the pH of the solution with a pH meter. Adjust if necessary to 5.0 to 5.5
   With technical grade hydrochloric acid to lower the pH or potassium hydroxide to raise the pH.
6. Add 3-4 litres of CLZ: 219 A and 50 ml of CLZ: 219 B with stirring.
7. Add sufficient water to bring solution to final operating volume.
8. Recheck pH and adjust if necessary. The plating solution is now ready for
   Production use.
   
   Production use.

   1 Liter
   Ammonium chloride	45	grams
   Potassium chloride	180	grams
   ZINCOBRITE CLZ LIQUID	60	ml
   ZINCOBRITE CLZ-912A	30-40	ml
   ZINCOBRITE CLZ-912B	0.60-0.80	ml
   Water to make	1	litre

Potassium Chloride/Ammonium Chloride
Potassium chloride or ammonium chloride used in making up and replenishing CLZ : 219 solutions must not contain humectants such as tricalcium phosphate, or
any organic additives. Use only chemical grade potassium chloride or ammonium chloride.

Rinsing
Rinsing after plating in CLZ :219 must be thorough and the last rinse tank should be clear at all times. After removal from the plating solution, allow the solution to drain from the parts above the plating tank or in are covery tank before water rinsing to reduce drag-out losses, thereby reducing operating cost.

Maintenance
Analyses the solution frequently so that it remains in chemical balance and will not require a large addition of chemicals at any one time to restore solution balance. Always analyze and adjust the zinc and chloride contents before adding CLZ: 219 A and CLZ: 219 B After making a corrective addition of potassium chloride and ammonium chloride in a 4:1 ratio by weight, measure the pH and adjust to the operating range use technical grade hydrochloric acid to lower the pH or with potassium hydroxide to raise the pH.
CZ 515 A may be used to increase the zinc metal content of the CLZ : 219 solution when the zinc metal content of the solutions is depleted too quickly to be replaced by the anodes, as in the case of excessive drag-out. In such cases, CLZ : 219 may be added to the operating solution to raise the zinc metal content. and total chloride content of the solution by 250 ml of CZ : 515 A added to 100 liters of operating solution will raise both the zinc metal content and total chloride content of the solution by 1 g/L).
The major factors that determine brightener consumption are drag-in of rinse water, drag-out of plating solution, temperature, and electrolysis. CLZ : 219 B consumption should range from 250 ml per 1000 Amp/ Hour. However, additions of CLZ : 129 B are best determined by plating cell test and visual observation of the work. There may be a tendency to add an excessive amount of CZ: 219 B to the plating solution based upon plating cell tests made without agitation. Part of the brilliance of the CLZ: 219 deposit obtained in production is due to agitation of the solution. Therefore, it is advisable to agitate the test cell solution during test plating.
Additions should be one part CLZ: 219 A for every 1 to 3 parts of CLZ: 219 B replenished based on operating experience and drag-out.

Agitation
Air agitation and solution circulation are highly recommended. Air agitation will help remove iron from the plating solution and reduce the need for hydrogen peroxide. Solution circulation may be achieved in large plating tanks in automatic lines by placing the intake and discharge of the filtration system at opposite ends of the tank, counter current to the workflow.
Low-pressure air (not compressed air) should be used and the blower intake should be equipped with a filter to remove particles to ensure that only clean air enters the solution. Do not place the blower air intake in an area where it may pick up acid fumes or other contaminants. The blower size formula is: 1 cubic foot per minute for each foot of perforated agitation pipe with blower pressure at 1 pound per square inch for each 18 inches of solution depth. Your local representative will be pleased to make recommendations concerning equipment.

pH Control
Maintain pH between 5.0 and 5.5 with frequent small additions of diluted technical grade hydrochloric acid. Never use acid that is green. When measuring pH use a meter.

Temperature
Optimum temperature is 27°C. Recommended operating temperature range is 21 to 41 °C.The solution can be operated above 38° but brightener consumption will increase significantly; however, deposits will be bright and level. The solution will operate at lower temperatures and produce bright level deposits; however, plating efficiency decreases at lower temperatures.

Impurities
The major contaminant in all chloride zinc plating solutions is iron. This contamination is normally controlled in the CLZ: 219 process by the use of air agitation along with solution filtration. If hydrogen peroxide is to be used, contact your local representative for the recommended procedure.

Leaching
The tank should be leached for 24 hours minimum as follows:
NOTE: If changing from a cyanide zinc process, introduction of acid may liberate cyanide gas. Cyanide gas is poisonous. Leaching should be done only with adequate exhaust ventilation. It may be necessary to have the exhaust scrubbed. 1. 2. 3.
Prepare a leaching solution consisting of 3% by volume technical grade hydrochloric
acid and 97% water. If possible, heat to 49°C to accelerate the leaching process.
Add 75 ml of CLZ- 219 A for each 100 liters of leaching solution.

Fill plating tank to the top of the tank and let solution stand for 24 hours.
Drain tank and rinse thoroughly with water.

If fiberglass tanks are used, leaching must be most thorough. In addition, the tank or lining manufacturer should warrant that no mold release was used in tank construction or specify the mold release and methods of removing any impregnation from the fiberglass.

FIRST AID: In case of contact of CLZ: 219 A, CLZ : 219 B, CZ 515 A LIQUID, pH adjusters, additives or the operating solution; immediately flush skin or eyes with plenty of water for at least 15minutes; for eyes seek immediate medical attention. Remove and wash contaminated clothing and shoes.

HANDLING INFORMATION: When making up or adding to solutions, always add CLZ: 219 A, CLZ: 219 B, CZ 515 A LIQUID, pH adjusters and additives slowly and cautiously. Do not get in eyes, on skin, or on clothing. Avoid breathing mist or vapors. When handling CLZ : 219 A, CLZ : 219 B, CZ : 515 A LIQUID, pH adjusters, additives or the operating solution wear chemical safety goggles, face shield, rubber gloves, respirator, and protective clothing. Avoid contamination with any other foreign material. Exhaust ventilation is recommended to remove dust, mist or vapors that may be generated during make-up and operation.

CONTAINER INFORMATION: Keep containers tightly closed. Store indoors in a cool, dry place. Loosen closure cautiously when opening containers. Wash
Thoroughly after handling. Do not reuse containers, wash before disposal. Improper disposal or reuse of containers may be dangerous and illegal.
REFER TO MSDS FOR FURTHER SAFETY AND HANDLING INFORMATION.

The following analytical procedures are recommended for use by personnel who have been trained to use laboratory practices which are considered safe and prudent by chemical industry standards. Such practices include suitable personal protective equipment, the use of proper equipment, the use of proper methods of handling all chemicals and proper laboratory procedures. Use only analytical reagent grade chemicals and deionized or distilled water in the following analytical procedures.

CAUTION: The following procedures involve the use of potentially hazardous chemicals. Consult manufacturer's material safety data sheets and follow the appropriate safety precautions.

Equipment Needed
2 ml pipette
25 ml graduated cylinder
50 ml burette
250 ml Erlenmeyer flask

Before analysis treat the solution with activated carbon (2-3 Gms/Litre) and filter.

Reagents Required

1. Ammonia Ammonium chloride Buffer Solution
2. Eriochrome Black T Indicator
3. 0.05 M E.D.T.A.
   

Reagents Required
4. Ammonia Ammonium chloride Buffer Solution
5. Eriochrome Black T Indicator
6. 0.05 M E.D.T.A.

1 ml 0.05 M E.D.T.A. = 0.003269 Gms Zinc

Burette reading X 1.635 = Gms/Litre Zinc

Reagent Required
1. Calcium Carbonate
2. Potassium Chromate Indicator
3. 0.1N Silver Nitrate

Pipette out 2 ml solution in a 500 ml conical flask. Add 50 ml distilled water and calcium carbonate in slightly excess to remove free acidity. Add Potassium Chromate Indicator till solution is distinctly yellow. Titrate with 0.1 N Silver Nitrate till appearance of reddish tinge on the precipitate.

Burette Reading x 1.773 = Gms/Ltr CL Total Chloride