FORD FLTM AZ 102-1-2000 PREPARATION OF STANDARD LABORATORY REAGENTS AND INDICATORS (Replaces FLTM AZ 002-01 FLTM EU-AZ 002-01).pdf

1、 FORD LABORATORY TEST METHOD AZ 102-01 Date Action Revisions 2000 08 22 Revised Editorial no technical change A. Cockman 2000 05 22 Editorial no technical change A. Cockman 199 4 01 03 Printed copies are uncontrolled Page 1 of 8 Copyright 2000, Ford Global Technologies, Inc. PREPARATION OF STANDARD

2、LABORATORY REAGENTS AND INDICATORS Application This procedure describes the preparation of standard solutions and indicators for use with Ford Laboratory Test Methods. Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23

3、 +/ - 2 C and 50 +/ - 5 % relative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Reagent No. 1 - Standard Sodium Hydroxide 1. Dissolve 100 g of C.P. NaOH in 100 mL of distilled water in a 400 mL Pyrex beaker. 2. Cool, transfer to a

4、300 mL Pyrex flask. Stopper and allow to stand approximately 48 hours to precipitate carbonates. (The solution may be filtered throug h a glass fritted crucible if needed sooner but CO 2 must be excluded during filtration). 3. Pipette the required number of milliliters of NaOH solution into a 1000 m

5、L volumetric flask and dilute to the mark with recently boiled and cooled distilled water and mix thoroughly. The following table shows the approximate amount of NaOH necessary to make 1 liter of stock solution of the required normality. Approximate Normality mL of NaOH 0.01 0.65 0.05 3.25 0.10 6.5

6、0.5 0 32.5 1.0 65.0 FORD LABORATORY TEST METHOD AZ 102-01 Page 2 of 8 Copyright 2000, Ford Global Technologies, Inc. 4. Standardize as follows: (a) Dry acid potassium phthalate (HKC 8 H 4 O 4), acidimetric standard for 2 hours at 120 C and cool in a desiccator. (b) Weigh a sufficient amount to give

7、a titration of approximately 40 mL which will vary according to the normality being prepared (1.0211 g is equivalent to 50 mL of 0.1 N NaOH solution). (c) Transfer the acid potassium phthalate to a 300 mL flask, dissolve in 50 mL of cool distilled water (23 +/ - 2 C) free of CO 2 . (d) Add 3 drop s

8、of phenolphthalein, Reagent No. 101 and titrate with the alkali to a faint pink color. g of HKC 8 H 4 O 4 = normality of the NaOH solution mL of alkali x 0.204 The solution should be slightly over - strength. Adjust to the exact normality by diluting with distilled water, using the following formula

9、: normality x volume of stock solution = volume after dilution desired normality Check the final strength of the alkali solution by titrating as before with acid potassium phthalate. Reagent No. 2 - Standard Alcoholic HCl - approximately 0.03 N Add 1 mL of concentrated HCl (Sp. Gr. 1.19) to 400 mL o

10、f methanol. Use a pipette with rubber bulb to measure and transfer the acid. Mix thoroughly and transfer 25 mL of the solution to a 100 mL Erlenmeyer fla sk and add 25 mL of distilled water. Add 2 - 3 drops of phenolphthalein (Reagent No. 101) and titrate with standard NaOH - 0.1 N to a pink end poi

11、nt. Adjust if necessary to approximately 0.03 N. mL of NaOH x normality = normality of alcoholic HCl solution 25 Reagent No. 3 - 0.01 N NaOH See Reagent No. 1 for preparation of this solution. FORD LABORATORY TEST METHOD AZ 102-01 Page 3 of 8 Copyright 2000, Ford Global Technologies, Inc. Reagent No

12、. 4 - Standard Hydrochloric Acid Solutions The following table shows the approximate amounts of C.P. concentrated HCl (Sp. Gr. 1.19) needed to make 1 li ter of solution of a required normality. Approximate Normality HCl Milliliters 0.01 0.9 0.05 4.5 0.10 9.0 0.50 45.0 1.0 90.0 Dilute the specified m

13、illiliters of acid needed for a desired normality to 10 00 mL with distilled water in a volumetric flask and mix thoroughly. Standardize against a sodium hydroxide solution of the same normality (prepared as directed under Reagent No. 1) as follows: (a) Measure 40 mL of the acid solution from a bure

14、tte into a 300 mL flask. Dilute to 100 mL with distilled water. (b) Add 2 - 3 drops of phenolphthalein (Reagent No. 101) and titrate to a faint pink color with standard NaOH. mL of standard NaOH x normality = normality mL of HCl The HCl solution should be over strength. Adjust to the exact normality

15、, using the following formula: normality x volume of stock solution = volume after dilution desired normality Check the final strength of the acid as before. Reagent No. 5 - Ammonia Carbon Dioxide-Free Water Ti me and difficulty in preparing ammonia - carbon dioxide - free water necessary to the det

16、ermination of nitrogen in most steels can be avoided by passing distilled water over a suitable ion exchange resin column. Reagent No. 6 - Ammonia-Free Sodium Hydroxide Solution Dissolve 1200 g of C.P. NaOH in two liters of ammonia - free water in a 3 liter Pyrex beaker. Cool and filter through glas

17、s wool into a polyethylene bottle. When cold, dilute with ammonia - free water to a specific gravity of 1.39 (hydrometer). Keep stock bottles tightly closed by polyethylene stoppers. FORD LABORATORY TEST METHOD AZ 102-01 Page 4 of 8 Copyright 2000, Ford Global Technologies, Inc. Reagent No. 7 - Stan

18、dard Sodium Arsenite Solution Dissolve 1.70 g of sodium arsenite (NaAsO 2) in 500 mL of distilled water containing 10 g of sodium carbonate (Na 2 CO 3 ) and dilute to 2 liters. Stan dardize against a similar iron, steel or iron ore containing approximately the same amount of manganese as the test sp

19、ecimen. Use the applicable test method and appropriate sample size. Reagent No. 8 - Ammonium Molybdate Solution A. Mix 177 g of 85 % mo lybdic acid in 600 mL of water, add 120 mL NH 4 OH slowly while stirring. Filter when solution is complete. B. In a stock bottle, add 600 mL of HNO 3 to 900 mL wate

20、r, mix and cool. Pour solution A into solution B slowly, using a thistle tube which is inser ted below the surface of solution B. Do this while agitating solution B with a current of air. Continue agitation for 2 hours. Let settle 24 hours and filter as needed. Reagent No. 9 - Standard Potassium Per

21、manganate Solutions 0.1 N - 9.6 g KMnO 4 /3 L 0.2 N - 19.2 g KMnO 4 /3 L For special purposes, 0.03 N, 0.02 N, and other strengths are prepared by dilution with CO 2 - free water. Weigh C.P. KMnO 4 and dissolve in 300 mL of distilled water. Let age for one week. Filter through a fritted glass crucib

22、le and store in a dark glass stoppered bottle. Standardize as follows: Weigh 0.3 g (0.6 g for 0.2 N KMnO 4 ) sodium oxalate and transfer to a 400 mL beaker. Dissolve in 200 mL of hot distilled water (80 C) and add 15 mL of dilute H 2 SO 4 (1:1). Titrate with the KMnO 4 solution, allowing the first f

23、ew drops to decolorize before adding more, then add at the rate of 10 15 mL/minute as soon as the permanganate color is destroyed. As the end point is approached, add the KMnO 4 drop by drop until a permanent pink color persists. weight of Na 2 C 2 O 4 = normality of KMnO 4 0.067 x mL of KMnO 4 FORD

24、 LABORATORY TEST METHOD AZ 102-01 Page 5 of 8 Copyright 2000, Ford Global Technologies, Inc. Reagent No. 10 - Ferrous Sulfate Solution - 0.1 N Transfer 40 g of FeSO 4 (NH 4 ) 2 SO 4 .6H 2 O or 28 g of FeSO 4 .7H 2 0 to a glass stoppered bottle and dissolve in a cooled mixture o f 100 mL of concentra

25、ted H 2 SO 4 and 900 mL of distilled water. Standardize as follows: Transfer 30 mL of the ferrous sulfate solution to an Erlenmeyer flask, dilute to 200 mL with cold dilute H 2 SO 4 (5:95), add 1 mL of H 3 PO 4 (85 %) and titrate immediately with standard 0.1 N KMnO 4 (Reagent No. 9) to a faint perm

26、anent pink color. mL KMnO 4 used x normality = normality of FeSO 4 mL of FeSO 4 solution Reagent No. 11 - E.D.T.A. Solution Dissolve 25.0 g of reagent grade disodium dihydrogen ethylene - diaminet etraacetate dihydrate in 500 mL of distilled water and dilute to 1000 mL in a volumetric flask. Standar

27、dize as follows: (a) Dissolve 11.16 g of pure granulated zinc metal in 200 mL of HCl (1:1) and dilute to 1000 mL with distilled water. This solution i s equivalent to 20 g/Liter Zn(CN) 2 . (b) Pipette 2 mL samples of the zinc solution into separate flasks and follow all the steps in the procedure bu

28、t omit the addition of HCl. 20 g/liter = factor (g/liter Zn(CN) 2 for 2 mL sample) mL E.D.T.A. Solutio n Reagent No. 12 - Standard Potassium Ferrocyanide Weigh 65.2 g of K 4 Fe(CN) 6 and dissolve in distilled water. Dissolve 0.4 g of potassium ferrocyanide K 3 Fe(CN) 6 in the solution (for better in

29、dication) and add 0.50 g of sodium carbonate Na 2 CO 3 and dissol ve. Dilute to 1000 mL in a volumetric flask and mix thoroughly. 1 mL of the above solution is equivalent to 0.015 g Zn/mL. FORD LABORATORY TEST METHOD AZ 102-01 Page 6 of 8 Copyright 2000, Ford Global Technologies, Inc. The potassium

30、ferrocyanide may be standardized as follows: (a) Dissolve 0.35 g of pure granulated zinc and 20 mL of HCl (1:1). (b) Dilute to 100 mL. (c) Make alkaline to litmus with dilute NH 4OH (1:1) and then just acid with HCl.(d) Add 15 mL of HCl (concentrated) in excess. (e) Add 5 drops of diphenylbenzidine

31、indicator (1 g of the reagent dissolved in 100 mL of concentrated H 2 SO 4 ). (f) Heat to 80 C and titrate with K 4 Fe (CN) 6 solution. 0.35 = grams of Zn/mL mL of K 4 Fe(CN) 6 grams of Zn/mL = titration factor 0.015 Reagent No. 13 - Standard Silver Nitrate - 0.1 N Weigh 16.989 g of C.P. AgNO 3 , di

32、ssolv e in distilled water and dilute to 1000 mL. Mix thoroughly and store in a dark glass stoppered bottle. Reagent No. 14 - Sodium Thiosulfate - 0.1 N Weigh 25 g of C.P. sodium thiosulfate (Na 2 S 2 O 3 . 5H 2 O) and 0.5 - 1.0 g of C.P. NaOH, dissolve in distilled water and dilute to 1000 mL. Reag

33、ent No. 15 - Potassium Dichromate - 0.1 N Weigh 4.9034 g of powdered C.P. potassium dichromate (K 2 Cr 2 O 7 ) (previously dried at 100 C for 1 hour and cooled to room temperature), transfer to a liter volumetric flask and di lute to the mark with distilled water. Reagent No. 16 - Sulfuric Acid - 0.

34、1 N Add 3 mL of C.P. H 2 SO 4 (Sp.Gr.1.84) to about 500 mL of distilled water and dilute to 1000 mL. Standardize as follows: (a) Weigh 0.2 g of C.P. anhydrous sodium carbonate (Na 2 C O 3 ) (previously dried at 110 C for at least 1 hour), to the nearest 0.0001 g. (b) Transfer to a 250 mL Erlenmeyer

35、flask, add 125 mL of distilled water and swirl until the carbonate is dissolved. FORD LABORATORY TEST METHOD AZ 102-01 Page 7 of 8 Copyright 2000, Ford Global Technologies, Inc. (c) Add 3 drops of 0.1 % methyl red indictor. (d) Titrat e with the sulfuric acid solution until the color changes from ye

36、llow to a light pink. (e) Calculate normality (N) according to the following equation: (g Na 2 CO 3 ) 18.87 = N of H 2 SO 4 mL H 2 SO 4 Preparation of Standard Laboratory Indicators Indicator No. 101 - Phenolphthalein Weigh 0.2 g of phenolphthalein, dissolve in 50 mL of ethyl alcohol and add 50 mL o

37、f distilled water. Indicator No. 102 - Bromo Cresol Purple Indicator Dissolve 0.5 g of bromo cresol purple crystals in 25 mL of distilled water and filter. Indicator No. 103 - Sodium Alizarin Sulfonate Dissolve 100 mg of sodium alizarin sulfonate in 100 mL of distilled water. Indicator No. 104 - Mix

38、ed Indicator Dissolve 0.1 g of bromo cresol green in 100 mL of 95 % ethyl alcohol. Dissolve 0.1 g of methyl red in 100 mL of 95 % ethyl alcohol. Mix five parts of bromo cresol green solution with one part of methyl red solution for use. Indicator No. 105 - Methyl Orange Dissolve 0.1 g of the reagent

39、 in 100 mL distilled water. Indicator No. 106 - Bromo-Thymol Blue Dissolve 0.1 g of the reagent in 50 mL of methyl alcohol and 50 mL of water. Indicator No. 107 - Methyl Red Dissolve 0.1 g in 100 mL of methyl alcohol. Indicator No. 108 - Bromo Cresol Green Dissolve 0.1 g in 50 mL of isopropyl alcoho

40、l and dil ute to 100 mL with distilled water. Indicator No. 109 - Bromo Phenol Blue Dissolve 0.4 g of the water soluble indicator in 100 mL of distilled water. FORD LABORATORY TEST METHOD AZ 102-01 Page 8 of 8 Copyright 2000, Ford Global Technologies, Inc. Preparation of Standard Laboratory Reagents

41、 Indicator No. 110 - Diphenylamine in Sulfuric Acid Dissolv e 1.0 g of diphenylamine into a beaker and cover the crystals with concentrated sulfuric acid. Add 1 - 2 mL of distilled water. After solution is complete, dilute to 30 mL with concentrated sulfuric acid. Indicator No. 111 - Iron Test Paper

42、 1 g of alpha, alpha prime dipyridyl (Fisher No. D 95) dissolved in 95 mL of alcohol and 5 mL of water. Immerse strips of paper in above solution and allow to dry. Indicator No. 112 - Potassium Chromate Dissolve 10 g of K 2 CrO 4 in distilled water and dilute to 100 mL. Indicator No. 113 - Starch So

43、lution Prepare a cold suspension of soluble starch by mixing 5.0 g of starch with 25 mL of distilled water. Add the suspension to 1000 mL of boiling distilled water and boil until clear. Cool and add 0.01 g of mercuric iodide to preserve the solution. Indicator No. 114 - Orthophenanthroline 1 1 10 - Orthophenanthroline ferrous complex 0.025 Molar solution (Ferroin). Chemicals, materials, parts, and equipment referenced in this document must be used and handled properly. Each party is responsible for determining proper use and handling in its facilities.