1、ANSI PH4.181- 1980 Revision of ANSI PH4.181-1961 (R1973) I I American National Standard specification for photographic grade benzyl alcohol CGHsCHzOH Approved August 9, 1979 Secretariat: National Association of Photographic Manufacturers, Inc c National Standard , with permission of the American Nat
2、ional Standards Institute, Inc. Not for resale. No part of this publication may be copied or reproduced in any form, electronic retrieval system or otherwise, without the prior written permission of the American National Standards Institute, Inc., 11 West 42nd Street, New York, New York 10036. Forew
3、ord 1. Scope Page 1 of 3 pages 88 rC: I - v) z a (This Foreword is not a part of American National Standard Specification for Photographic Grade Benzyl Alcohol, ANSI PH4.181-1980.) This is one of a series of standards that establishes cri- teria of purity for chemicals used in processing phot graphi
4、c materials. These criteria are the minimum re- quirements necessary to assure sufficient purity for use in photographic processing solutions, except that if the purity of a commonly available grade of chemi- cal exceeds photographic processing requirements and if there is no economic penalty in its
5、 use, the purity requirements have been set to take advantage of the availability of the higher quality material. Although the ultimate criterion of the suitability of a photographic grade chemical is its successful perfor- mance in a photographic use test, the shorter and more economical tests desc
6、ribed are generally adequate. All tests are performed on samples “as received” to reflect the condition of materials furnished for use. Some of these procedures utilize caustic, toxic, or otherwise hazardous chemicals. Warnings are given when special hazards exist, but normal precautions required in
7、 the performance of any chemical procedure must be exer- cised at all times. This standard is a revision of American National Standard Specification for Photographic Grade Benzyl In this latest revision, the format has been updated, pre- cautions have been added, and the section on physical appearan
8、ce and stability has been replaced with a sec- tion on general information. Alcohol, CgHSCH2OH, ANSI PH4.181-1961 (R1973). This standard states the purity requirements and test methods for photographic grade benzyl alcohol. 2. General Information 2.1 Physical Properties. Benzyl alcohol is a clear, c
9、olor- less liquid; it has a molecular weight of 108.14 (based on Carbon-1 2). 2.2 Hazardous Properties. When benzyl alcohol is ex- posed to light and air for an extended time, especially at higher than normal storage temperature, small amounts of benzaldehyde are produced. 2.3 Shipping and Storage C
10、onditions. Benzyl alcohol should be stored in a cool location; high temperatures should be avoided. There are no DOT shipping re- strictions. 3. Summary of Requirements Residue after Ignition: 0.002% rnax Specific Gravity: 1 .O48 min- 1 .O54 max 1 .O42 min-1 .O48 max at i 511 5C at 2512 5” C Benzald
11、ehyde (C6H5CHO): 0.1% max Halides (as Ci): 0.005% max Identity: To pass either chemi- cal identity test or infrared identity test Solubility : To pass test CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Insti
12、- tute require that action be taken to reaffirm, revise, or withdraw this standard no later than five years from the date of publication. Purchasers of American Printed in USA National Standards may receive current information on all standards by calling or writing the American National Standards In
13、stitute. Copyright 01980 by American National Standards Institute, 1430 Broadway, New York, N.Y. 10018 ANSI5C180/225 STD-ANSI IT4-LBL-ENGL 1980 = 0724350 0542477 777 Page 2 of 3 pagea 4. Reagents for Test Methods 4.1 Purity of Reagents 4.1.1 Reagents used in the test procedures shall meet the specif
14、ications given in Reagent Chemicals, published by the American Chemical Society in 1974, wherever such specifications have been established. If no American Chemical Society specifications exist, the purity shail be that generally used for careful analytical work. 4.1.2 Wherever water is specified, i
15、t shall be distilled or deionized water. 4.2 Strength of Solutions 4.2.1 Acids and ammonium hydroxide shall be full strength unless otherwise specified. 4.22 When a standardized solution is required, its concentration is expressed as normality, N. The number of significant figures to which the norma
16、lity is known shall be sufficient to ensure that the reagent does not limit the reliability of the test method. its concentration is expressed in grams per liter (glL) to the appropriate number of significant figures. 4.2.4 When a solution is to be diluted, its dilution is indicated by (1 + X), mean
17、ing that one volume of a reagent, or concentrated solution, is to be diluted with X volumes of water. 4.2.3 When a standardized solution is not required, 5. Residue after Ignition (0.002% maximum) Cautiously evaporate 1 O0 grams f 1 gram of the sample to dryness in a tared platinum dish on a sand ba
18、th at approximately 300C and then ignite the residue at 600C I2S“C for 4 hours. Cool in a desiccator and weigh. The weight of the residue shall not exceed 0.002 gram. 6. Specific Gravity (1.048 minimum-1 .O54 maximum at 1511 s“C; or 1.042 minimum-1.048 maximum at 25/25C) Determine the specific gravi
19、ty by any reliable method. Available from the American Chemical Society, 1155 Six- teenth Street, N.W., Washington, D.C. 20036. ANSI PH4.181-1980 7. Benzaldehyde ( C6 HS CHO) (0.1% maximum) 7.1 Reagent: pNitrophenylhydrazine Solution Dissolve 0.6 gram of pnitrophenylhydrazine hydrochloride2j3 in 20
20、mL of hydrochloric acid.“ Dilute .to 100 mL with hot water. Filter before using. 7.2 Procedure. Pipet 5 mL of the sample into a beaker containing 150 mL of boiling water. Stir until dissolved. Add 50 mL of p-nitrophenylhydrazine hydrochloride and let stand for 3 hours. Filter with the aid of vacuum
21、through a tared fritted crucible of fine poros- ity. Wash the precipitate several times with dilute hydro- chloric acidzy3 (1 + 4) and, finally, with water. Dry the crucible and its contents for 4 hours at 105“C, cool in a desiccator, and weigh. The weight of the contents shall not exceed 0.01 2 gra
22、m. 8. Halides (0.005% maximum as Ci) 8.1 Reagent: Silver Nitrate Solution. Dissolve 10 grams of silver nitrate2 in water and dilute to 100 mLwith water. 8.2 Procedure. Place 25.0 mL of the sample and 25 mL of approximately 0.5 M alcoholic potassium hydroxide4 into a 250-mL conical flask and reflux f
23、or 2 hours. Trans- fer the solution to a platinum dish and evaporate on a steam bath until the volume is reduced to about half of the original volume. Complete the evaporation on a sand bath, taking care to avoid spattering, and then ignite at 600C f 25C until the residue is white. Cool, take up the
24、 residue with 3 mL of nitric acid,4 rinse the dish thoroughly with water, and transfer to a 250-mL volu- metric flask. Dilute to the mark with water, and mix well. Transfer a 5-mL aliquot of this solution to a 50- mL Nessler color comparison tube, dilute to the mark with water, add 2 drops of silver
25、 nitrate reagent,2 and mix well. Any turbidity produced shall not exceed that produced by 0.002 gram of sodium chloride treated in the same manner as the sample. WARNING Avoid contact with eyes, skin, and clothing. Wash thoroughly after handling. in case of contact, flush eyes and skin with water. O
26、btain medical attention immediately. sWARNING Harmful if inhaled. Avoid breathing dust, vapor, mist, and gas. Use only with adequate ventilation. If inhaled, move to fresh air. Obtain medical attention immediately. 4DANGER Corrosive, causes burns. Avoid contact with eyes, skin, and clothing. Use wit
27、h adequate ventilation. in case of contact, flush with water. Obtain medical attention immedi- ately. I Page 3 of 3 pages WAVE NUMBERS IN CM-l 5000 4000 3000 2500 2000 1500 1400 1300 1200 1100 1000 900 800 700 025 u1 100 a 80 O z E 8 60 z E 40 I- z w a: w a o 20 no 2 3 4 5 7 6 9 IO II 12 13 14 15 I0
28、 WAVE LENGTH IN MICROMETERS Fig. 1 infrared Spectrum Reference Curve (Benzyl Alcohol) 9. Identity (To pass either chemical identity test or infrared iden- tity test) 9.1 Chemical Identity Test 2 grams of anhydrous sodium carbonate in water and dilute to 1 O0 mL. to be tested and a derivative of a sa
29、mple known to be benzyl alcohol, as follows. Boil 2 mL of sample cau- tiously with 0.5 gram of 3,5-dinitrobenzoyl chloride2. in a test tube for 5 minutes. Cool to room temperature, add 10 mL of water, and cool in an ice bath until solid- ification results. Remove the precipitate, place it in a small
30、 filter, and wash with 1 O mL of the sodium car- bonate solution. Dissolve the precipitate in 12 mL of hot 95-percent ethyl alcoh01, add 3 mL of water, reheat to dissolve any precipitate resulting from the addition of the water, and crystallize the product by cooling. Wash the precipitate twice with
31、 a cold (ice bath) mixture of 1 part water and 1 part ethyl alcoh01. Dry on a porous plate. Assemble capillary tube melting-point apparatus using a thermometer which covers the range of 100C- 20OoC. Repare three capillary tubes, placing in them (I) the derivative of the sample to be tested, (2) the
32、derivative of the known sample, and (3) a finely ground mixture of (1) and (2) mixed in the ratio of 1 :1. Iden- tify the tubes and attach them to the thermometer. Heat the bath to approximately 1 OOC and then in- crease the heat at a constant rate of 1 degree per min- ute, stirring constantly. Note
33、 the melting point of the contents of each tube as indicated by the first appear- CAUTION: Flammable. Keep away from heat, sparks, and 9.1.1 Reagent: Sodium Carbonate Solution. Dissolve 9.1.2 Rocedure. Prepare a derivative of the sample open flame. Use with adequate ventilation. ance of liquefaction
34、. The melting point of the mixture shall be no lower than the lower of the two derivatives. The sample derivative should melt at approximately 11 l“C-114“C. 9.2 Infrared Identity Test. The sample shall have the absorption characteristics of benzyl alcohol. 9.2.1 Apparatus. Infrared spectrophotometer
35、 equipped for the 2- to 16-micrometer region; a liquid- absorption cell with sodium chloride windows and a path length of about 0.01 mm (millimeter), or a sand- wich-type cell having sodium chloride plates ground on the inner surfaces with 280-grit paper. 9.2.2 Rocedure. Fill the absorption cell wit
36、h the sample and obtain the infrared spectrum over the 2- to 16-micrometer range. Make a qualitative identification by comparison of the sample curve with the reference curve shown in Fig. 1. 10. Solubility (To pass test) 10.1 Reagent: Acidified Methyl Red Indiator. Dissolve 0.10 gram of methyl red
37、in 100 mL of ethyl alcohol5 and add 1 drop of dilute sulfuric acid4 (1 + 4). 10.2 Procedure. Pipet 2 mL of the sample into a 100 mL glass-stoppered, graduated cylinder containing 50 mL of water. Add 4 drops of the acidified methyl red indiator, stopper the cylinder, and shake it vigorously for 2 min
38、utes. Allow the mixture to stand for 5 minutes to ensure complete removal of air bubbles. Compare this solution with 50 mL of water containing 4 drops of the acidified methyl red indicator4 in a similar cylinder. Note the presence or absence of turbidity or insoluble oily globules accentuated by the indicator. Their pres- ence indicates failure “to pass test.“ ANSI PH4.181-1980
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