Preliminary Requirements

Safety Requirements

WARNING

IT IS THE RESPONSIBILITY OF THE OPERATOR TO OBTAIN AND OBSERVE THE MANUFACTURERS MATERIAL SAFETY DATA SHEETS FOR CONSUMABLE MATERIALS INFORMATION SUCH AS, HAZARDOUS INGREDIENTS, PHYSICAL/CHEMICAL CHARACTERISTICS, FIRE, EXPLOSION, REACTIVITY, HEALTH HAZARD DATA, PRECAUTIONS FOR SAFE HANDLING, USE AND CONTROL MEASURES AND ALSO TO TAKE LOCAL REGULATIONS INTO CONSIDERATION.

WARNING

THIS PROCEDURE INCLUDES THE USE OF SODIUM HYDROXIDE, SODIUM CYANIDE OR POTASSIUM CYANIDE. CYANIDE SALTS AND/OR SOLUTIONS ARE VERY POISONOUS AND WORK VERY QUICKLY. THEY GIVE OFF HYDRO-CYANIC GAS, WHEN MIXED WITH ACID, WHICH CAN KILL. THE PRECAUTIONS THAT FOLLOW MUST ALWAYS BE OBEYED.

WARNING

CYANIDE SALTS AND SOLUTIONS MUST ALWAYS BE KEPT AWAY FROM ACIDS.

WARNING

A FUME EXTRACTOR MUST ALWAYS BE USED.

WARNING

OPERATORS MUST ALWAYS USE THE APPROVED PROTECTIVE CLOTHING SUPPLIED.

WARNING

FINGERNAILS MUST BE KEPT SHORT AND MUST ALWAYS BE FULLY CLEANED BEFORE YOU EAT, DRINK OR SMOKE.

WARNING

ITEMS THAT ARE USED TO EAT OR DRINK WITH MUST NOT BE KEPT AT LOCATIONS WHERE CYANIDE IS KEPT OR USED. ALSO, YOU MUST NOT EAT DRINK OR SMOKE, AT SUCH LOCATIONS.

WARNING

CYANIDE MUST ALWAYS BE KEPT AT A SAFE LOCATION, WHERE ACCESS IS ONLY AVAILABLE TO APPROVED PERSONS.

WARNING

A SUPPLY OF CYANIDE ANTIDOTE MUST ALWAYS BE EASILY AVAILABLE.

WARNING

THE INSTRUCTIONS GIVEN BY THE SAFETY OFFICER MUST ALWAYS BE OBEYED.

WARNING

EVERY POSSIBLE CARE MUST BE TAKEN TO AVOID THE SOLUTION COMING INTO CONTACT WITH THE EYES OR BARE SKIN, PROTECTIVE CLOTHING INCLUDING RUBBER GLOVES AND EYE PROTECTION MUST BE PROVIDED FOR THE OPERATORS. RUBBER GLOVES SHOULD BE CHECKED REGULARLY FOR PIN HOLES AND REPLACED IF NECESSARY.

EXTREME CARE MUST BE TAKEN WHEN HANDLING THE ACIDS, PARTICULARLY HYDROFLUORIC ACID.

SAFETY NOTICES MUST BE PLACED IN A CONSPICUOUS PLACE.

EYE-WASH BOTTLES AND HF JELLY MUST BE PROVIDED AS CLOSE AS POSSIBLE TO THE PLACE OF WORK.

IF SKIN BECOMES CONTAMINATED WITH THE SOLUTIONS IT MUST BE RINSED WITH COPIOUS AMOUNTS OF CLEAN RUNNING WATER.

ALL BURNS, HOWEVER SLIGHT, SHOULD BE TREATED AT THE NEAREST SURGERY OR FIRST-AID POST.

THE SURGERY MUST BE TOLD WHICH SOLUTION (I.E. THE ACIDS INVOLVED) HAS CAUSED THE BURN, THIS APPLIES PARTICULARLY WHEN HYDROFLUORIC ACID IS A CONSTITUENT.

Procedure

1. SUBTASK 70-33-16-200-001 Silver Strike Solution

   1. Analyze the silver strike solution for silver content:

      1. Use a safety pipet, to transfer a 25 ml sample of the silver strike solution to a beaker.

      2. 

         WARNING

         BECAUSE HYDROCYANIC GAS WILL BE GIVEN OFF, DURING THE FOLLOWING OPERATION, A FUME EXTRACTOR MUST BE USED AND EXTREME CARE MUST BE TAKEN.

         Put the beaker and solution sample into a fume cupboard, then carefully add approximately 10 ml of CoMat 01-058 NITRIC ACID HNO3. Evaporate down to dryness.

      3. Cool, then add a further 10 ml of the nitric acid.

      4. Dilute to approximately 100 ml, with CoMat 01-201 DISTILLED, DEIONIZED, DEMINERALIZED, OR REVERSE OSMOSIS (RO) WATER. Boil and then cool.

      5. Add a few ml of CoMat 01-074 FERRIC ALUM then titrate, with an N/10 solution of CoMat 01-075 AMMONIUM THIOCYANATE NH4SCN, to a permanent red color:

         1. 1 ml of N/10 ammonium thiocyanate equals 0.01079 g of silver.

         2. ml of ammonium thiocyanate x 0.43 equals g/l of silver.

   2. Analyze the silver strike solution for free potassium cyanide content:

      1. Use a safety pipet, to transfer a 10 ml sample of the silver strike solution to a beaker.

      2. Add a few drops of CoMat 01-086 AMMONIUM HYDROXIDE SOLN NH4OH and a few crystals of CoMat 01-097 POTASSIUM IODIDE KI.

      3. Titrate, with an N/10 solution of CoMat 01-059 SILVER NITRATE AgNO3, to a faint yellow turbidity:

         1. ml of N/10 silver nitrate x 1.29 equals g/l of free potassium cyanide.

2. SUBTASK 70-33-16-200-002 Silver Plating Solution

   1. Analyze the silver plating solution for silver content:

      1. Use a safety pipet, to transfer a 10 ml sample of the silver plating solution to a beaker.

      2. 

         WARNING

         BECAUSE HYDROCYANIC GAS WILL BE GIVEN OFF, DURING THE FOLLOWING OPERATION, A FUME EXTRACTOR MUST BE USED AND EXTREME CARE MUST BE TAKEN.

         Put the beaker and solution sample into a fume cupboard, then carefully add approximately 50 ml of CoMat 01-058 NITRIC ACID HNO3. Evaporate down to dryness.

      3. Cool, the add a further 10 ml of the nitric acid.

      4. Dilute to approximately 100 ml, with CoMat 01-201 DISTILLED, DEIONIZED, DEMINERALIZED, OR REVERSE OSMOSIS (RO) WATER. Boil and then cool.

      5. Add a few ml of CoMat 01-074 FERRIC ALUM then titrate, with an N/10 solution of CoMat 01-075 AMMONIUM THIOCYANATE NH4SCN, to a permanent red color:

         1. ml of N/10 ammonium thiocyanate x 1.079 equals g/l of silver.

   2. Analyze the silver plating solution for free potassium cyanide content:

      1. Use a safety pipet, to transfer a 5 ml sample of the silver plating solution to a beaker.

      2. Add a few drops of CoMat 01-086 AMMONIUM HYDROXIDE SOLN NH4OH and a few crystals of CoMat 01-097 POTASSIUM IODIDE KI.

      3. Titrate, with an N/10 solution of CoMat 01-059 SILVER NITRATE AgNO3, to a faint yellow turbidity:

         1. ml of N/10 silver nitrate x 2.58 equals g/l of free potassium cyanide.

3. SUBTASK 70-33-16-200-003 Nickle Chloride Strike Solution

   1. Analyse for nickel chloride content.

      1. Gravimetric method.

         1. Transfer, by using a pipette, 10 ml. of sample solution to a 100 ml. standard flask.

         2. Dilute to the mark and shake well.

         3. Pipette 10 ml of this solution into a suitable beaker.

         4. Add a few CoMat 01-087 TARTARIC ACID CRYSTALS and dilute to approximately 150 ml with distilled water.

         5. Heat to 158 to 178 deg F (70 to 80 deg C) and make just alkaline with CoMat 01-086 AMMONIUM HYDROXIDE SOLN NH4OH.

         6. Add 40 ml of 1 percent CoMat 01-088 DI-METHYL GLYOXIME, stir and allow to precipitate for 30 minutes.

         7. Filter on a 15.0 cm CoMat 02-012 FILTER PAPER and wash well with hot distilled water.

         8. Wrap the filter paper in another paper, dry, ignite at 1472 deg F (800 deg C) and weigh as nickel oxide.

            1 g of nickel oxide is equivalent to 3.18 g of nickel chloride therefore g of precipitate x 3.18 x 1.000 = g/litre nickel chloride.

      2. Volumetric method.

         1. Pipette 2 ml of sample to a suitable conical beaker.

         2. Dilute to approximately 100 ml with distilled water.

         3. Add 20 ml of CoMat 01-086 AMMONIUM HYDROXIDE SOLN NH4OH and 0.5 g of CoMat 01-089 MUREXIDE INDICATOR.

         4. Titrate against standard N/5 solution of CoMat 01-090 ETHYL. DIAMINE TETRA ACETICACID, the end point being indicated by a change in colour from light brown through red brown to violet.

            1. As 1 ml of N/5 ethyl diamine tetra-acetic acid solution is equivalent to 0,.0237 g of nickel chloride, the following will then apply to a 2 ml sample:

            2. g/litre nickel chloride = Titration value x factor of ethyl diamine tetra-acetic acid x 11.9.

   2. Analyse for hydrochloric acid content.

      1. Pipette 5 ml of sample solution into a suitable beaker and dilute to approximately 30 ml with distilled water.

      2. Add a few drops of CoMat 01-064 INDICATOR and titrate very slowly with a solution prepared from CoMat 01-008 SODIUM HYDROXIDE NaOH (CAUSTIC SODA), SOLID until the red colour is destroyed; the following will then apply:

         1. g/litre hydrochloric acid = ml of N sodium hydroxide x 0.0365 x 200.