1、c ANSI PH4*l8h 87 0724350 OOLl270 7 Revision of ANSI PH4.1861980 O American National Standard s a An American National Standard implies a consensus of those substantially concerned with its scope and provisions. An American National Standard is intended as a guide to aid the manufacturer, the consum
2、er, and the general public. The existence of an American National Stan- dard does not in any respect preclude anyone, whether he has approved the standard or not, from manufacturing, marketing, purchasing, or using products, processes, or procedures not conforming to the standard. American National
3、Standards are subject to periodic review and users are cautioned to obtain the latest editions. The American National Standards Institute does not develop standards and will in no circumstances give an interpretation of any American National Standard. Moreover, no person shall have the right or auth
4、ority to issue an interpretation of an American National Standard in the name of the American National Standards Institute. CAUTION NOTICE: This American National Standard may be revised or withdrawn at any time. The procedures of the American National Standards Instituterequire that action be taken
5、 to reaffirm, revise, or withdraw this standard no later than five years from the date of ap- proval. Purchasers of American Nationai Standards may receive current information on aU standards by calling or writing the American Na- tional Standards Institute. : for photography (chemicals) - hydroxyla
6、mine sulfate Approved October 16, 1986 Secretariat: National Association of Photographic Manufacturers, Inc I I Warning and Safety Precautions Some of the chemicals specified in the test proce- dures in this standard are corrosive, toxic, or otherwise hazardous. Specific caution, warning, and danger
7、 notices are given in the footnotes but, in addition, the normal precautions required dur- ing the performance of any chemical procedure must be exercised at ail times. It is recommended that anyone using these chemicals obtain from the manufacturers pertinent information about the hazards, handling
8、, and use of these chemicals. Such information is usually furnished by the chemical manufacturer in the form of a material safety data sheet. I Page 1 of 4 pages Introduction (This Introduction is not part of American National Standard PH4.186-1987.) This standard is one of a series that establishes
9、 criteria of purity for chemicals used in processing photographic materials. Although the ultimate criterion for suitability of a photographic-grade chemical is its successful perfor- mance in an appropriate use test, the shorter, more economical tests described herein are generally adequate. This s
10、tandard is a revision of American National Standard Specification for Photographic Grade Hy- droxylamine Sulfate, (NH20H), H2 SO4 (hydroxyl- ammonium sulfate) (oxammonium sulfate), ANSI PH4.186-1980. In this latest revision, the section on “Physical Appearance” has been replaced with a sec- yllniuul
11、nmm-q American National Standards Institute, 1430 Broadway, New York. J,Y. 10018 ANSI 5C281/4 7 / Page 2 of 4 pages tion on “General Information, The section on “Re- agents for Test Methods” has been renamed “Reagents, Materials, and Glassware.” Strength of standard solu- tions is now expressed as m
12、olarity. Also, minor changes in precaution notations have been made, and the gen- eral format has been changed to be in agreement with the style outlined in the Directives for the Technical Work of the International Organization for Standardi- zation (ISO). 1. Scope This standard establishes criteri
13、a for the purity of pho- tographic-grade hydroxylamine sulfate and describes the tests to be used to determine the purity. 2. General Information 2.1 Physical Properties. Hydroxylamine sulfate exists in the form of colorless or white crystals or powder, The chemical formula is (NH, OH), H, SO4 and t
14、he relative molar mass is 164.14. 2.2 Hazardous Properties. Hydroxylamine sulfate is irritating to eyes and skin and is harmful if swallowed. Aqueous solutions are very acidic. 2.3 Storage and Handling. Hydroxylamine sulfate should be stored in a cool dry place where contact with alkalines is unlike
15、ly. Under alkaline conditions (pH 7 or higher), free hydroxylamine is liberated. The decom- position of hydroxylamine under alkaline conditions can be rapid and explosive. 3. Summary of Requirements Assay (“,OH), aHzSO4 97.0 (m/m) minimum Residue after ignition 0.05% (m/m) maximum Heavy metals (as P
16、b) 0.001% (m/m) maximum Iron (Fe) 0.001% (m/m) maximum Ammonium (NH4) To pass test NOTE: m/m = Mass per mass (weight per weight) 4. Reagents, Materials, and Glassware 4.1 Reagents health and safety precautions, as shown on containers 4.1.1 Reagents shall be handled in conformity with or as given in
17、other sources of such information. Proper labeling of prepared reagents includes name, date of preparation, expiration date, restandardization date, and adequate health and safety precautions, The dis- posal of reagents and all materials shall conform to applicable environmental regulations. . certi
18、fied reagent grade chemicals and shall meet the specifications given in Reagent Chemicals published by the American Chemical Society (ACS) in 198 1, or chemicals of a purity acceptable for the analysis. The acids and ammonia solutions referred to in ail the in- structions shall be of full strength u
19、nless dilution is specified, Dilution is specified in terms of molarity,M, when standardization is required, The number of signif- icant figures to which molarity is known shall be suffi- cient to ensure that the reagent does not limit the reli- ability of the test method. When dilution is indicated
20、 as (1 + X), it means that one volume of the specified reagent is added to X volumes of distilled water. 4.1.2 Reagents used in the test procedures shall be 4.2 Water. Whenever water is specified in the fest pro- cedures, only distilled water or water of at least equal purity shall be used. 4.3 Glas
21、sware. All glassware subject to heating shall be of heat-resistant glass, for example, Pyrex or equivalent. 5. Test Procedures The test procedures described in Sections 6 through 10 shall be followed to determine whether the test sample meets the purity requirements listed in Section 3. Tests shall
22、be made on samples in their “as received” condition. In the last several years, there have been great im- provements in instrumentation for various analyses. Where such techniques have the equivalent accuracy and precision, they may be used in place of the tests described in this standard. 6. Assay
23、97.0% (m/m) minimum (NH, OH)z Hz SO4 6.1 Reagent - Standard Potassium Permanganate Solu- tion, 0.02M (3.16 g/L). Analyzed reagent solution is recommended. This is commercially available from several vendors. i Sold under names such ns oxammonium sulfate, Iiydroxyl- ammonium dihydroxylamine sulfate.
24、Available from American Chemical Society, 1155 Sixteenth Street, NiV, Washington, DC 20036. ANSI PH4.186-1987 /- y -. ANSI P“i-1Bb 87 1111 0724150 OOLI272 O Page 3 of 4 pages 6.2 Apparatus. In addition to ordinary laboratory ap- paratus, a buret, straight-type Pyrex or equivalent, with Teflon stopco
25、ck, 50-mL capacity shall be used. r 6.3 Procedure. Take about 0.14 gram of the sample, weigh it to the nearest 0,0001 gram and dissolve it in 20 mL of water in a 500-mL conical flask. Boil gently for a few minutes to expel oxygen, cover the top of the flask with an inverted beaker, and set aside. Di
26、ssolve 5 grams of ferric ammonium sulfate dodecahydrate FeNH4(S04)2 12Hz0 in 30 mL of dilute sulfuric acid3 (1 t 50), boil gently for a few minutes, and trans- fer while hot to the flask containing the dissolved sam- ple. Boil the solution gently for 5 minutes while exclud- ing air using a gentle st
27、ream of nitrogen over the solu- tion, Cool, dilute with 150 mL of freshly boiled and cooled water, and titrate with 0.02M potassium per- manganate4 to the first persistent pink color. Percent hydroxylamine sulfate 1 d - (Vj (0.4104) Weight of sample where V = volume of 0.02 M KMn04 in milliliters us
28、ed in the titration. 7. Residue after Ignition a O.OS% (m/m) maximum Weigh 2.0 grams of sample in a weighed crucible and carefully heat until nearly all of the sample is volatil- ized. Cool and add 2 to 3 drops of sulfuric acid.3 Slowly raise the temperature until the sample and acid have been volat
29、ilized, and finally ignite at 800C f 25C for 15 minutes. The weight of the residue shall not exceed 0,0010 gram. Save the residue for the iron procedure described in 9.2. 8. Heavy Metals 0.001% (m/m) maximum as Pb 8.1 Reagents Dissolve 1.80 grams of lead acetate trihydrate 8.1.1 Heavy Metals Standar
30、d (1 mL = 0.01 mg Pb). 3DANGER: Corrosive, causes burns. Avoid contact with eyes, skin, and clothing. Wash thoroughly after handling. In case of contact, flush eyes and skin with water. Obtain medical atten- tion immediately. 4WARNING: Oxidizer, Contact with other material may cause fire. Do not sto
31、re near combustible materials. WARNING: Harmful if inhaled. Avoid breathing dust, vapor, mist, and gas. Use only with adequate ventilation. If inhaled, move to fresh au and obtain medical attention immediately. Pb(C2H302)2 3Hz0 weighed to the nearest 0.01 gram, in water, transfer to a 1-liter volume
32、tric flask, dilute to the mark, and mix weil. Pipet a 10-mL ali- quot of this solution into a 1-liter volumetric flask, dilute to the mark with water, and mix well, sodium sulfide, nonahydrates (Naz S 9Hz O) in 100 mL of water. 8.2 Procedure. Dissolve 5.0 grams f 0.1 gram of the sample in water and
33、dilute to 40 mL with water in a Nessler color comparison tube. Dilute 5 .O mL of the Heavy Metals Standard (8.1 .i) to 40 mL in another Nessler color comparison tube. Add one drop of sodium sulfide5 solution to each of the tubes, and mix well. Any color produced in the sample solution shall not be g
34、reater than that produced in the treated heavy metals standard solution. 8.1.2 Sodium Sulfide Solution. Dissolve 5 grams of 9. Iron 0.002% (m/m) maximum Fe 9.1 Reagents 9.1.1 iron Standard(1 mL = 0.004 mg Fe). Dissolve 1.40 grams of ferrous ammonium sulfate, hexahydrate, Fe(NH4)2(S04)2 6Hz0 in 50 mL
35、 of water, and add 20 mL of dilute sulfuric acid3 (1 t 15). Transfer to a 1-liter volumetric flask, dilute to the mark with water, and mix well, Dilute a 10-mL aliquot of this solution to 500 mL with water in a 500-mL volumetric flask, and mix well. 9.1.2 pH 5 Acetate Buffer. Add 23 grams of anhy- d
36、rous sodium acetate to 60 mL of dilute acetic aid, (1 t 8) and dilute with water to 1 liter. Adjust the final pH of the solution to 5.0 k 0.1 with dilute acetic aid, or sodium hydroxide solution3 (100 g/L). 9.1.3 1 ,lo-Phenanthroline Mixture. Thoroughly mix equal parts by volume of an aqueous soluti
37、on of 1,lO-phenanthroiine (1 g/L), a solution of hydroxyl- amine hydrochloride (100 g/L), and pH 5 acetate buffer (9.1.2). of p-nitrophenol in 100 grams of water. 9.2 Procedure. Add 3 mL of dilute hydrochloric aid, (1 t 5) to the crucible containing the residue 9.1.4 p-Nitrophenol Indicator. Dissolv
38、e 0.25 gram DANGER: Combustible. Keep away from heat, sparks, and open flame. Use with adequate ventilation. WARNING: Avoid contact with eyes, skin and clothing. Wash thoroughly after handling. In case of contact, flush eyes and skin with water. Obtain medical attention immediately. ANSI PH4.186-198
39、7 - ANSI PH4aLBb 87 lkg 0724350 0033273 2 Is Page 4 of 4 pages from the Residue after Ignition procedure described in Section 7, cover dish, and warm it over a hot plate for 15 to 20 minutes. Remove the cover, and rinse the underside with a small amount of water, catching the rinsewater in the cruci
40、ble. Transfer the solution with washing to a 100-mL beaker. Pipet 10.0 mL of the Iron Standard (9.1 .i) into a second 100-mL beaker, and adjust the volume of both beakers to about 30 mL by adding water. Add 2 drops of p-nitrophenol indicator (9.1.4) to each solution, and add dilute am- monium hydrox
41、ides7 (1 t 9) dropwise to each beaker until the solutions turn yeliow. Add dilute hydro- chloric acid3$ (1 t 99) dropwise until the solutions become colorless, and then add 0.5 mL in excess. Add 5 mL of the 1 ,IO-phenanthroiine mixture (9.1,3), mix well, and let stand for 10 minutes. Dilute to 50 mL
42、 with water, mix well, and transfer to Nessler color com- parison tubes for comparison. Any color produced in the sample solution shall not exceed that produced in the Iron Standard solution. ANSI PH4.186-1987 +- - J 10. Ammonium (NH4) (To passtest) 10.1 Equipment 10.1.1 Use an infrared spectrophoto
43、meter that will measure absorptions in the infrared region from 2.5 to 15 micrometers, 10.1.2 A pellet press is recommended. 10.2 Procedure 10.2.1 Weigh out 10 mg of the dry sample and 390 mg of spectrographic grade potassium bromide (KBr). Grind the mixture to produce a homogeneous mixture, and pre
44、ss it into a pellet in a die. Determine the adsorp- tion of the pellet at 7.14 micrometers. The absorbance should not be more than 0.06 about 0.1% ammonium 10.2.2 If a pellet press is not available, the sample may be ground with a spectrographic grade mineral oil to produce a uniform mull that is placed between two plates of potassium bromide using a spacer. A calibra- tion sample will be required with known amounts of an ammonium salt to bracket the amount of ammonium expected in the sample. (“411 * n
