FORD FLTM AK 111-01-2000 QUANTITATIVE ANALYSIS OF BORATES IN CLEANERS《清洁剂中的硼酸盐含量的定量分析》.pdf

1、 FORD LABORATORY TEST METHOD AK 111-01 Date Action Re visions 2000 08 31 Revised Editorial no technical change A. Cockman 2000 03 23 Editorial no technical change A. Cockman 1992 06 03 Printed copies are uncontrolled Page 1 of 4 Copyright 2000, Ford Global Technologies, Inc. QUANTITATIVE ANALYSIS OF

2、 BORATES IN CLEANERS Application This test method is used to determine the percent borate in a cleaner. The procedure is intended to be a simplified version of the applicable ASTM standard (e.g., D 501 or D 800) as well as being more appropriate for dealing with the many formulations of cleaners tha

3、t are commonly encountered in plant operations. Apparatus Required Analytical Balance Precision +/ - 0.1 mg Hot Plate Titration Apparatus Graduated Cylinder or Flask Erlenmeyer Flask 250 mL Pipet Funnel Suitable for use with filter paper Container Should be of sufficient size to hold the 250 mL Erle

4、nmeyer flask (in a bath of cold water). The above apparatus is available from any reputable laboratory equipment supply house. Materials Required Hydrochloric Acid 6N, Reagent grade; CAUTION: Corrosive Barium Chloride Reagent grade; CAUTION: Poisonous FORD LABORATORY TEST METHOD AK 111-01 Page 2 of

5、4 Copyright 2000, Ford Global Technologies, Inc. Barium Hydroxide Reagent grade; CAUTION: Poisonous Phenolphthalein Ethyl Alcohol Reagent grade; CAUTION: Low flash point Mannitol or Glycerol Reagent grade Distilled or Deionized Water 10 ppm max total dissolved solids (ASTM D 1888) Filter Paper Whatm

6、an No. 541 Solutions Required Barium Chloride Solution 10 % concentration (dissolve 100 g of barium chloride in distilled water and dilute to 1 L). Hydrochloric Acid Solution 0.5 N Sodium Hydroxide Solution 0.5 N Methyl Red Indicator Dissolve 0.1 g of methyl red in 100 mL of methyl alcohol Phenolpht

7、halein Indicator Dissolve 0.2 g of phenolphthalein in 50 mL of ethyl alco hol and add 50 mL of distilled water Conditioning and Test Conditions All test values indicated herein are based on material conditioned in a controlled atmosphere of 23 +/ - 2 C and 50 +/ - 5 % relative humidity for not less

8、than 24 h prior to testing a nd tested under the same conditions unless otherwise specified. FORD LABORATORY TEST METHOD AK 111-01 Page 3 of 4 Copyright 2000, Ford Global Technologies, Inc. Procedure 1. Place a 0.5 to 1.0 g aliquot of the prepared 1 % solution of cleaner into a 250 mL Erlenmeyer fla

9、sk. 2. Add a few drops of methyl red indicator. 3. Add sufficient 6N hydrochl oric acid to give a red color and about 0.3 - 0.5 mL excess. 4. After covering the flask, place on hot plate. 5. Gently heat to simmering temperature (avoid vigorous boiling). Ten minutes at temperature is sufficient to ex

10、pel carbon dioxide. 6. The solu tion is then cooled by placing the flask into a container of cold water. 7. 10 mL of a 10 % barium chloride solution is added to the flask. 8. Cover flask and heat to simmering on the hot plate. Vigorous boiling is to be avoided since boric acid is vola tile with stea

11、m. Let simmer for 15 minutes. 9. Remove flask from hot plate. 10. Gradually add powdered barium hydroxide with a spatula to the solution until the red color changes to yellow. Note: More methyl red indicator may have to be used in order to be sure the solution is acid prior to the addition of barium

12、 hydroxide. 11. Return covered flask to hot plate and simmer for 15 minutes. 12. Cool solution. 13. Filter the precipitate (normally yellow in color) through a Whatman No. 541 filter paper. 14. Rinse with distilled water until chloride free. Usually 10 washings are required prior to testing for chlo

13、rides; refer to FLTM AK 118 - 01. The filtrate shall be yellow in color. 15. Add 0.5 N hydrochloric acid until the solution becomes acidic. Colo r change from yellow to red. FORD LABORATORY TEST METHOD AK 111-01 Page 4 of 4 Copyright 2000, Ford Global Technologies, Inc. 16. Add 1 - 2 mL excess hydro

14、chloric acid. 17. Simmer solution for 15 min to expel any carbon dioxide that might be present. 18. Cool the flask and contents under cold running water. 19. Titrate the excess acidity with 0. 5 N sodium hydroxide until the solution changes from red to yellow. A drop of the sodium hydroxide will giv

15、e the yellow color at the end point. The free boric acid can now be titrated. 20. Add 4 - 8 g of mannitol (or 25 - 50 mL of glycerol). 21. Add 1 mL of phenolphthalein indicator. 22. Titrate 0.5 N sodium hydroxide until a faint pink color is obtained, and then add a drop or two more until the color i

16、s a definite reddish - pink, the true end point. 23. Add an additional one g of mannitol (or 5 mL of glycerol). If incomplete titration has been done, the solution will become yellow. 24. If this happens, continue titration until the reddish - pink end point is again obtained. 25. Steps 23 and 24 ma

17、y have to be repeated more than once. 26. Calculate th e percent of borates as B 2 O 3 . % B 2 O 3 = mL 0.5 N NaOH x 0.01741 x 100 weight sample used 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.