FORD FLTM AK 113-01-2001 QUANTITATIVE ANALYSIS OF NITRATE (NO3) IN CLEANERS《清洁剂中的硝酸盐（NO3）含量的定量分析》.pdf

1、 FORD LABORATORY TEST METHOD AK 113-01 Date Action Revisions 2001 01 22 Revised Editorial no technical change A. Cockman 2000 03 23 Revised Editorial no technical change A. Cockman 1991 09 24 Printed copies are uncontrolled Page 1 of 3 Copyright 2001, Ford Global Technologies, Inc. QUANTITATIVE ANAL

2、YSIS OF NITRATE (NO3) IN CLEANERS Application This test method is used to determine the percent nitrate in a cleaner. Apparatus Required Analytical Balance Precision +/- 0.1 mg Distillation Apparatus Distillation Flask Kjeldahl (or boiling type) with ground glass joints. Hot Plate Pipet Titration Ap

3、paratus Graduated Cylinder or Flask Glass Boiling Beads The above apparatus is available from any reputable laboratory equipment supply house. Materials Required Sodium Hydroxide Reagent grade; CAUTION: Corrosive Hydrochloric Acid Concentrated, Reagent grade; CAUTION: Corrosive Devardas Alloy Powder

4、ed. FORD LABORATORY TEST METHOD AK 113-01 Page 2 of 3 Copyright 2001, Ford Global Technologies, Inc. Methyl Red Reagent grade. Methyl Alcohol CAUTION: Low flash point Red Litmus Paper Distilled or Deionized Water 10 ppm max total dissolved solids (ASTM D 1888). Solutions Required Sodium Hydroxide So

5、lution 0.5 N; Refer to FLTM AZ 102-01 Hydrochloric Acid Solution 0.5 N; Refer to FLTM AZ 102-01 Methyl Red Indicator Refer to FLTM AZ 102-01 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 % rel

6、ative humidity for not less than 24 h prior to testing and tested under the same conditions unless otherwise specified. Procedure 1. Take a 1 to 2 g aliquot of the prepared 1 % solution of cleaner into a 1 000 mL distilling flask (Kjeldahl of boiling type) with ground glass joints. 2. Dilute to 300

7、mL with distilled water. 3. Add glass boiling beads. 4. Buret 40 mL of 0.5 N hydrochloric acid into a 500 mL receiving flask. 5. Add a few drops of methyl red indicator. 6. Connect this flask to the condenser making sure that the outlet glass tube from the condenser is immersed in the acid. FORD LAB

8、ORATORY TEST METHOD AK 113-01 Page 3 of 3 Copyright 2001, Ford Global Technologies, Inc. 7. To the sample in the distilling flask, add 50 mL of a 50 % sodium hydroxide solution, free from ammonia, and then 5 g of powdered Devardas Alloy. Note: Make sure the sodium hydroxide does not touch the ground

9、 glass joints. 8. Immediately connect the flask to the water condenser by means of the glass connecting arm with the ground glass joints. Note: All joint connections must be tight. 9. When the initial reaction subsides, swirl the flask for complete solution of the sample and the sodium hydroxide. 10

10、. Heat the distilling flask. 11. Collect approximately 200 mL of the distillate in the receiving flask. 12. Check for completeness of distillation by opening the tube in the distilling flask and determining the neutrality of the vapors with moist red litmus paper. 13. When the distillation is comple

11、te, disconnect the apparatus at the receiving end of the condenser. 14. Shut off the heat. 15. Wash down the condenser and the glass tubing with distilled water into the receiving flask. 16. Titrate the excess acid with standard 0.5 N sodium hydroxide. 17. Calculate the % of NO . 3 % NO 3 = (mL 0.5

12、N HCl - mL 0.5 N NaOH) x 0.031 x 100 Weight of Sample Note: 1. Ammonium-bearing compounds and nitrates will contribute to the total titration found if they are present. 2. Organic-bearing nitrogen compounds will interfere with this determination. 3. If nitrites and/or ammonium are present, the nitra

13、te must be determined by another means. When determined, they must be deducted from the total nitrogen found in order to calculate the % of nitrate nitrogen. 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.