1、t ANSI/I3AIdd) Rewsion of sNSI PH4.303-1977 ! American National Standard for photography (chemicals) - potassium persulfate Approved June 12, 1984 Secretariat: Natlonal Association of Photographic Manufacturers, Inc Warning and Safety Precautions Some of the chemicals specified in the test proze- du
2、res m this standard are caustic. to-.uz. or other- wise hazardous. Speclfrc caution, warning, and danger notrces are given m the footnotes but. in addltlon. the normal precautions requned durmg the performance of any chemical procedure shall be excrclsed at all tmies It 1s recommended that anyone us
3、mg these chemicals obtains from the manufacturers pertinent mformdtlon about the halards. handlmg. and use of these chemrcals. Such Information IS usually furmshed by the chemical manufacturer in the form of a manufac- turers material safety data sheet (OSHA Form 20 or equivalent). I 1 Page 1 of 4 p
4、ages Introduction (Thz Introductmn is not part of American NatIonal Standard ANSI/AK PH4.303-1984.) Ttus standard 1s one of a selles that establishes the mm- mum criteria of purity for chemicals used in processing photograptnc materials. Although the ultimate criterion for stntablhty of a photograpt
5、uc-grade chemical 1s Its successful perfor- mance m an appropriate use test. the shorter. more economIcal tests described m tlus standard are gener- ally adequate. This standard IS a revlslon of American NatIonal Standard Speclficatlon for Photographlc Grade Potas- slum Persulfate (Potassmm Peroxydl
6、sulfate). Kz Sz 0,. ANSI PH4.303.1977 In this latest revlslon. the section on physlcdl appearance has been replaced with a sec- tlon on general InformatIon. mmor changes m precau- tlun notations have been made. and the general format has been changed to be m agreement with the style outhncd in the D
7、IrectIves for the Techmcal Work of the International Orgamzatlon for Standardrzatlon (ISO). An Amerwan National Stmdard lmphes a conenrus of those wbstantlally concerned wth 115 scope md provwons An American National Standard 1s Intended a) a gmde to ald the manufacturer, the consumer, and the gener
8、al pubhc. The existence of an American National Stan- dard does not m any respect preclude anyone, whether he has approved the standard or not, from manufacturmg, marketmg, purchasmg, or using products, processes, or procedures not conformmg to the standard American NaUonaJ Standards are subJect to
9、penodlc review and users are cauttoned to obtain the latest edltwns The American NatIonal Standards Institute does not develop standards and wll m no cxcumstances gwe an mterpretation of any American National Standard. Moreover, no person shall hdve the right or authority to lseue an mterpretatlon o
10、f an Amenc.m Naflonal St.mdard m the name of the Amencan Natwnal Standards InWtute. CAUTION NOTICE: T?w American National Standard may bc rewed or wthdrawn at any time. The procedures of the American Natxmal Standards Institute requtre that actmn be taken to reaffirm. rewe. or wthdraw this standard
11、no later than five years from the date of ap- proval. Purchasers of American Natlonal Standards may receive current mformatlon on all standards by callmg or wrltmg the American Na- tmnal Standards Institute. CopyrIght 0 1994 by American National Standards Institute, 1430 Broadway, New York, N.Y. 100
12、19 4NSISC884/4 Page 2 of 4 pages 1. Scope This standard estabhshes crlterla for the purity of photographlc-grade potassmm persulfate and describes the tests to be used to determme the purny. 2. General Information 2.1 Physical Properties. Potassium persulfate exists m the form of white odorless crys
13、tals. granules. or pow- der and 1s water soluble. The chemical formula IS K2 Sz O8 The relative molar mass IS 270.3. 2.2 Hazardous Properties. Potassium persulfate IS a potent oxidlzmg agent. particularly m the presence of strong alkalies. It reacts with many materials: therefore. care shall be exer
14、cised in its use It decomposes under heat to give off oxygen and toxic sulfur trloxlde. 2.3 Handling and Storage Conditions. For storage pur- poses. potassmm persulfate shall be labeled as an oxtdiz- mg material. Store m a cool. dry locatlon separate from combustible. organic. or other readily oxldi
15、Lable mate- rials. 3. Specification Assay (Kz Sz OS ) 98.03 (m/m) mimmum Halides (as Cl). 0 006:; (m/m) maximum Heavy Metals (as Pb), 0 OOSF (m/m) maxnnum Iron (Fe) 0 005% (mini) maxmium Appearance of 12 Solution To pass test NOTE m/m = mass per mass 4. Reagents, Materials. and Glassware 4.1 Reagent
16、s 4.1.1 Reagents shall be handled 111 conformity to health and safety precautions as shown on containers or as given m other sources of such Information Proper labelmg of prepared reagents Includes adequate health and safety precautions. The discharge of reagents shall conform to applicable environm
17、ental regulations. 4.1.2 Reagents used m the test procedures shall be certified reagent-grade chemicals and shall meet the speclflcatlons given m Reagent Chemicals, pubhshed by the Amertcan Chemtcal Societ) (ACS) tn 1981. or chemicals of a purity acceptable to the analysis. The _- Avadable from Amer
18、an Chcmlc.d Socxt) 1155 Sixteenth Street. NM. WashIngon. DC 20036 ANSIIASC PH4.303-1984 acids and ammonia solutions referred to in all the in- structions shall be of full strength unless dilution 1s specified. Dllutlon is specified m terms of norm for example. Pyrex or equivalent. 5. Tests Tests sha
19、ll be made on the samples m the “as received” condition The test procedures described m Sections 6 through 10 shall be followed to determine whether the test sam- ple meets the purity requirements hsted in Section 3. In the last several years. there have been great Im- provemcnts in instrumentation
20、for various analyses. Where such techniques have the equivalent accuracy and preclslon. they may be used m place of the tests described In this standard. 6. Assay 98.0% (m/m) minimum K2 S2 O8 6.1 Standard Sodium Thiosulfate Solution, 0.1 N (NalSzO,). Dissolve 25 grams of sodium thiosulfate. pentahyd
21、rate (Na2 SZ O3 * 5H2 0). and 2 to 3 grams of sodium tetraborate. pentahydrate (Naz Bz O4 * 5H2 0). m 1 liter of boding water. Allow to cool. 6.2 Salicylic Acid Solution, 1% by Weight. Add 10 grams of sahcyhc acid* to 500 mllihters (mL) of dis- tilled water. Stir until dissolved. Dilute to 1 liter w
22、ith water, 6.3 Starch Indicator Solution. Stir 5 grams of soluble starch with 100 mL of 19 sahcyllc acid solution (6.2) Add 300 to 300 mL of boiling water and boll until the stalch dissolves Dilute to 1 hter with water. WARNING: Corrosive, CDUSCS burns. Avwd contact wth eyes, tkm. and clothmp. Wash
23、thoroughly after hondlmp. In case of contact. flush eyes and skm wth nater. Obt.un medical atten- tlon unmcdlatelg . .; Page 3 of 4 pages 6.4 Standardization of Sodium Thiosulfate Solution. Wergh 0.135 gram of potassium lodate (KIOs) Trans- fer the sample to a 500.mL Erlcnmeycr flask and add 200 mL
24、of water. Add 4 grams of potassrum rodtde (KI). swrrl to drssolve. and then add 30 mL of glactal acettc acrd.3 Tttrate with the sodium thtosulfate solu- tion (6.1). addmg 2 mL of starch mdrcator solutron (6.3) when the solutton becomes pale yellow. Tttrate to a colorless end pomt. Calculate the norm
25、ahty of the sodrum thiosulfate solutron usmg the followmg equation. Normahty of Naa Sa 0s (grams of KIOa) (I 000 mL/L) = (35.7 grams per equation) (mL of Naz Sa 0s) 6.5 Procedure. Take about 0.5 gram of the sample and wergh accurately to the nearest 0 001 gram Trans- fer the sample to a glass-stoppc
26、red iodme flask and add 25 mL of freshly prepared potassmm rodtde solutron (100 g/L). Dissolve the sample and add 10 mL of dilute sulfurrc actd3 (1 + 5). Allow to stand m the dark for 1 hour. Trtrate the liberated rodrne with 0.1 IV sodrurn throsulfate usmg starch mdrcator. Percent K2S20s (mLNa,S,03
27、)(Na2S203)(13 52) =- werght of sample m grams 7. Halides 0.006% (m/m) maximum as Cl 7.1 Standard Chloride Solution (1 mL = 0.01 mg Cl). Drssolve 0.165 gram f 0.001 gram of sodrum chlorrde. NaCl, rn 500 mL of water m a 1 hter volumetric flask. Dilute to 1 hter wrth water and mrx well. Prpet a IO-mL a
28、liquor into a lOO-mL volumetrtc flask. dilute to the mark with water. and mix well. Label 111s solutron “Standard Chloride Solutron.” 7.2 Apparatus. Two matched Nessler color comparr- son cylinders. 50 mL capaaty. 7.3 Procedure. Take about 3 3 grams of the sample and vvetgh to the nearest 0.0001 gra
29、m Transfer the sample to a 100mL volumetrrc flask contamrng about 50 mL of water. Shake w:ell to drssolve the sample. then drlute with water to the 100.mL mark. Stopper the flask and invert it 2 to 3 tmies to ensure proper mtxmg. Prpet 10 mL of this solutron to one of the 3DANGER: Corroswe, causes b
30、urns Avoid contxt rith eyes, skin, and clothing. Wash thoroughly after handlmg. In cast of contact. fluqh eyes and skm alth nater Obtun medIcal atten- tmn mnnedintely. Nessler color comparison cyhnders (7.2). Transfer 2 nlL of the standard chloride solutron (7.1) to the other Nessler color compartso
31、n cyhnder (7.2). To each cylinder add 1 mL of dtlute nttrrc acrd3 (1 t 9) and drlute to 50 mL wrth water Next add I mL of silver nitrate soIutron3*4 (100 g/L) to each cyhnder and mrx well. The turbidrty produced by the treated sample shall not exceed that produced by the treated standard chlortde so
32、lution. 8. Heavy Metals O.OOS% (m/m) maximum as Pb 8.1 Heavy Metals Standard (1 mL = 0.1 mg Pb). Drssolve 1.8 grams _+ 0.1 gram of lead acetates Pb(C2Hs0,)2 * 3Ha 0 in 500 mL of water m a I -liter volumetric flask. Drlute to the mark with water. stopper the flask. and invert rt 3 to 4 times to ensur
33、e proper mixmg. Pipet a IO-mL ahquot of this solutron into another 1 -liter volumetric flask. Dtlute to the mark with water and mrx well. Label thus solutron “Heavy Metals Standard.” 8.2 Apparatus. Two matched Nessler color comparison cylinders. 50.mL capacrty 8.3 Procedure. Wergh 1 .O gram of sampl
34、e to the nearest 0 0001 gram and transfer to a 100mL beaker contam- mg 25 mL of water. Prpet 5 mL of the heavy metals standard solutton (8.1) into a second IOO-mL beaker and drlute with 25 mL of water. Into a third 100.mL beaker. ptpet 2 mL of the non standard (9.1) and drlute with 25 mL of water. T
35、reat both standards and the sample solutron rn the followmg manner Add 15 mL of hydrochloric acrd36 and evaporate to dryness on a steam bath. Take up the residue with 25 mL of water. Add 2 drops of p-mtro- phenol indicator (2.5 g/L aqueous solution). Add, dropwrse. dilute hydrochlortc actd3.6 (1 t 9
36、9) until the solutron becomes colorless and then add 2.5.mL excess Warm for 10 minutes on a steam bath. Cool. dilute to 50 mL with water. and mrx well. To 20.111L aliquots of the heavy metals standard and the sample solutron save the non standard and the remammg sample solu- tron for the rron test I
37、n (9 S) . add 5 mL of hydrogen sulfide water.4.6 drlute to 50 mL. and mrx well. Trans- DANGER: Powan. May be fatal or cause blmdness If swal- loued. Harmful if Inhaled. If swallowed, Induce vomlttng. Ob- tan medtcal attention tmmedlatelq. WARNING: Harmful if mhaled. AvoId breathmg dust. Use only wth
38、 adequate vcntdatmn. If Inhaled, move to fresh au. Obtam medical attentton mnnediatcly. 6 DANGER: Harmful If inhaled. Avad breathmg dust, vapor, nut. or gas. Use only wh adequate vcntilatmn. If Inhaled, move to fresh air. Obtain medxal attentmn mmediately. ANSIIASC PH4.303-1984 -I- Page 4 of 4 pages
39、 fer to Nessler color comparison cylmders (8 2) for vrsual comparrson. Any color produced m the sample solutron shall not exceed that produced in the treated heavy metals standard solutron 9. Iron 0.0057c (m/m) maximum 9.1 Iron Standard (1 mL = 0.01 mg Fe). Drssolve 0.70 gram + 0.01 gram of ferrous
40、ammomum sulfate Fe(NH,)a(SO1)a -6H,O m 500 mL of water m a 1 -hter volumetrrc flask. Add 20 mL of ddute sulfurrc asId (1 + 15) and then dilute to the mark with water. Stopper the flask and invert rt 3 to 4 tnnes to ensure proper mrxmg. Pipet a IO-mL ahquot of thus solution Into a 100.mL volumetrrc f
41、lask. drlute to the mark wrth water, and mtx well. Label thus solutron “Iron Standard Solution.” 9.2 pH 5 Acetate Buffer Solution. Drssolve 23 grams of anhydrous sodrum acetate m 50 mL of drlute glacral acetic acrd3 (1 t 8) and drlute to 1000 mL wrth water Adjust the final pH of the solutron IO 5 0
42、i 0.1 wrth drlute glacral acetrc acrd3 (1 + 8) or wrth sodrum hy- droxrde3 (100 g/L). 9.3 l,lO-Phenanthroline Reagent Solution. Thor- oughly mrx equal volumes of 1 g/L aqueous solutron of 1 .IO-phenanthroline. a 100 g/L aqueous solution of hydroxylamine hydrochlorrde.7 and pH 5 acetate buffer solutr
43、on (9.2). 9.4 Apparatus. Two matched Nessler color comparrson cylmders. 50.mL capactty 9.5 Procedure. To 20-mL ahquots of the tron standard (9 1) and the sample solutron prepared in 8.3. add 5 mL of 1 ,lO-phenanthroline mrxture (9.3). mix well, and let stand for 10 nmutes. Drlute to SO mL wrth water
44、. Max well, and transfer to hessler color comparr- son cyhnders (9.4) for visual comparison. Any color produced m the sample solutron shall not exceed that produced m the treated Iron standard solutron. 10. Appearance of 1R Solution To pass test 10.1 Procedure. Drssolve IO grams of the sample in 1 later of water. 10.2 Appearance. The solution shall be clear. colorless. and free from any sedrment WARNING: Avmd contact wtth eyes, skm, and clothmg. uash thoroughly after handhng. In case of contact, flush ekes and skm wth water. Obtam medical attention mme- dlately ANSI/AX PH4.303-1984
