CQRROSION AND STABILITY STUDIES'

T h e lack of knowledge of how t o handle, store, and ship hydrogen peroxide of more than 5070 concentration neces- sitated the studies of stability a...
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CQRROSION AND STABILITY STUDIES’ F R E D E R I C K B E L L I N G E R 2 ,H . 6 . FRIEDMAN*, W . H. B A U E R 3 ,J. W . E A S T E S 4 ,A N D W. C.B U L L C H E M I C A L W A R F A R E S E R V I C E , E D G E W O O D A R S E N A L . MD.

T h e l a c k o f knowledge of h o w t o handle, store, a n d s h i p hydrogen peroxide of m o r e t h a n 5070 c o n c e n t r a t i o n necessitated t h e studies of s t a b i l i t y a n d corrosion of concent r a t e d hydrogen peroxide a n d c a l c i u m permanganate as reported here. C o m m e r c i a l steel d r u m s were f o u n d satisfactory f o r s h i p m e n t a n d storage o f permanganates. F o r use w i t h concentrated (80 t o 90%) peroxide, a l l s u r faces required preconditioning b y a n acid wash followed usually by a peroxide soak. A f t e r such c o n d i t i o n i n g , , a Iuminu m magnesi um a Iloys, Pyrex, a Iumin um 99.6% tin, t a n t a l u m , c a d m i u m , stainless steel types 304 a n d 316

are s u i t a b l e m a t e r i a l s o f c o n s t r u c t i o n f o r process equipare satisfactory f o r m e n t ; Pyrex a n d a l u m i n u m 99.6%+ storage containers. Koroseal a n d polyethylene are s u i t able f o r gasket materials. Silicone grease i s satisfactory as a l u b r i c a n t a n d does n o t affect peroxide. T h e s t a b i l i t y o f peroxide is a n inverse f u n c t i o n o f t h e i m p u r i t i e s present. Of t h e s t a b i l i z i n g agents investigated, phosphates give t h e best results; b u t above a c e r t a i n concentration, addit i o n a l a m o u n t s increase t h e r a t e of decomposition. C o n centrated peroxide c a n n o t be “detonated” by shock unless organic m a t e r i a l also i s present.

NTELLIGENCE reports frequently carried statements of French civilians that explosions occurred a t launching sites as a result of the instability of concentiated hydrogen peroxide. The literature (6) mentions violent explosions of this material. On the other hand, the work of Maas and associates ( 2 ) shows i t is quite stable when sufficiently purified. California Institute of Technology has a sample of 9Syc peroxide which has been stored for about two years in an ordinary Pyrex Erl’enmeyer flask covered by an inverted beaker and has been satisfactorily stable. Concentrated permanganate solutions were assumed not to differ materially from more dilute solutions with respect to handling and stability, and this assumption was confirmed by the data obtained. I n this country dilute aqueous solutions of hydrogen peroxide are generally concentrated by vacuum distillation to a maximum of about 35%, with the addition of stabilizers if desired ( 3 ) . Such

a solution may contain appreciable quantities of foreign material, depending upon its source and intended use. Table I gives typical analyses. One of the simplest ways to produce a concentrated hydrogen peroxide solution is to distill t,he water from commercial products (30-35%) and leave behind in the still pot a residue of concentrated hydrogen peroxide. The differences in boiling points of water and pure peroxide make this relatively easy to accomplish by vacuum distillation in a short fractionating column. A 90yG hydrogen peroxide solution so prepared contains all of the nonvolatile. impurities and stabilizers present in the starting material so that their concentrations are roughly three times those in the original dilute peroxide. The concentrated peroxide can then be distilled over to give a product free of nonvolatile materials. This further distilhtion must be carried out with more care and caution than the water-removal stage bccause the concentration of nonvolatile matter in the still pot continues to increase as the peroxide distills over. There is danger that a point may be reached where the rcmaining peroxide will decompose

+

-

I

The first paper i n this series appeared i n February, 1946, page 160. Present address, Georgia School of Technology, Atlanta, Ga. a Present address, Rennselaer Polytechnic Institute, Troy, N. Y. 4 Present address, Calco Chemical Company, Bound Brook, K. Y 1

2

310

March, 1946

INDUSTRIAL AND ENGINEERING CHEMISTRY

rapidly or even explosively in the pres-ence of this high salt concentration. Once the peroxide has been distilled over, it can be redistilled with less danger from this source. The stability of the distilled peroxide depends upon how successfully the entrainment of impurities has been avoided. Because of the interest in 80-900/, hydrogen peroxide and the possible demand for large-scale production, the Buffalo ElectroChemical Company developed a method for a stable extremely pure product. A pilot plant was erected and operated, and 90% peroxide was available in 30-gallon drums in time to supply the needs of this work. This process involved multiple distillation of the commercial product, and this process was so regulated that undue concentration and heating of nonvolatiles with concentrated peroxide were avoided. Table I1 shows that the final product contained very little other than peroxide and water. Buffalo Electro-Chemical Company believes that the stability of their concentrated peroxide depends upon its high purity-that is, the absence of components other than water and peroxide. Concentrated hydrogen peroxide was made in this laboratory by removing water from 30-35y0 commercial products and by complete distillation. The distillations were carried out in vacuo in all-Pyrex apparatus; a manostat controlled the pressure maintained by a Cenco Hyvac pump. The pump was protected by two traps cooled by solid carbon dioxide and acetone. A Vigreux column, about 2 feet long and 1 inch in diameter, was used between the still pot and the total-reflux, partial take-off, still head. The Vigreux column was jacketed so that water could be run through it if desired. Table I11 is a compilation of all distillation data obtained in this laboratory. The concentration and amount of peroxide in the initial fractions and the resulting yield and concentration of peroxide in the product (still pot residue) for runs 25, 27, 28, 30, and 31 compared with runs 18-21 and 24 show that better separation of water from peroxide was obtained in a cooled column. The peroxide recovery data indicate that concentrated peroxide can be prepared by vacuum distillation a t pressures up to a t least 30 mm. without undue thermal decomposition of peroxide. Satisfactory recovery of peroxide was obtained both by stopping with the concentrate in the still pot and by distilling the peroxide over, but the former procedure was better (runs 16 to 31). STABILITY TESTS

PRESSURE DEVELOPMENT. An all-glass closed-end manometer was used to determine decomposition as indicated by the .development of pressure (Figure l), The apparatus consisted of a bulb connected through a trap to a piece of capillary tubing containing a short length of mercury. The mercury was introduced through the open end of the capillary and positioned, and the errd of the capillary sealed. The peroxide (5 ml.) was placed in the bulb through the side filling tube which was then sealed. If a metal test strip was to be used, i t was sealed into the tube before the liquid was added. At any stated time the pressure in atmospheres was calculated from the formula: where

P = Pl(Ll/L2) initial pressure (1 atm.) distance from top of capillary to mercury thread a t time of filling L = same at time of reading

El 1 1

More accurately this formula should be:

+

R = pi(L/LZ) (L/760) where p1 = initial pressure in capillary before sealing, atm. L = length of mercury thread, mm. Owing to the nature of the measurements, the first equation was regarded as sufficientlyaccurate, assuming a n initial pressure of one atmosphere. STABILITY AT 100' C . The peroxide was found t o be relatively stable a t 100" C.; 86.7% peroxide samples were heated 24, 48,

311

TABLE I. ANALYSIS OF COMMERCIAL HYDROGEN PEROXIDE Superoxol (Merok)* 29 600 1000 10 250 50 Ammonia, 6.p.m. Sodium. D.D.m. Tin, p.p.m.Silica, p.p.m. Nitrate, p.p.m.

..

BeccoC D u Pant0 34.9 35.2 1240 340 310 .4bsent abs. 2 360 460 380 50

...

370 330 40 31

... ... ...

..

Specifications on label.

Pa. Salt Mfg. C0.a 28.1 960 140

..

80 60

abs. 50 30

,

56

b Data supplied b y company.

...

190 20 ' 50 11

190 Our analysis.

PEROXIDE TABLE 11. COMPOSITION O F 90% HYDROGEN BUFFALOELECTRO-CHEMICAL COMPANY

Drum No.

HzOz,

%

90.3 90.1 90.4 89.2 89.2 90.0 @

Nonvolatile Matter, P.P.M. 11

AcidityP.P.M. H&Oc

31

..

6 12 7

26 27 31 40

8 10

FROM

pHb 4.24 4.47 4.71 4.56 4.36 4.31

B titration of a dilute solution 1:lO with distilled water.

b A&er dilution

96, and 168 hours. At the end of each period they analyzed 85.7, 83.9, 83.1, and 80.4% peroxide, respectively. HOT WIRE. To determine the effect of sudden application of a high temperature to a small part of the peroxide, lengths (2.5 inches) of 24-gage copper wire, 8-gage silver wire, and 32-gage platinum wire, were separately immersed in concentrated peroxide, and 110 volts were applied across the ends. The wire in each case instantly fused, but the peroxide was apparently unaffected. CORROSION TESTS

The standard 30-gallon d r u was chosen as the container for calculating ratios of volume to surface from the formula:

aV/A where V

=

+

rw~h/2(~ h)

A

= total volume of container = total inside area of container

ff

=

fractional filling

aVIA = volume/surface ratio = rsRlius of container r h

=

height of container

It was not convenient to vary the sizes of test pieces to correspond to each of the differentvolumes of peroxide used in the tests; consequently, two different sizes were chosen. One was calculated to providq ten times, the surface for a 5-ml. sample as used in the pressure tests and in studies with small test tubes; i t had the following dimensions in inches: length 1.14, width 0.276, thickness 0.079. The other was calculated for a 150-ml. sample to be used in larger scale tests; its dimensions were length 2.08, width 0.851,thickness 0.079 inch. Visual observation of such changes as discoloration and pitting was made. The pieces were weighed before and after test, and the corrosion was calculated by the usual formula: W(O.001) C = (2.54)s AST .

.

where C = corrosion, inches penetration/month W = weight loss, mg. A = area of sample, sq. in. S = density of sample, grams/cc. T = time of test, months Corrosion tests were made in connection with stability tests by placing pieces of the material in the manometer. For corrosionstability tests a t ambient temperature, the test pieces were wholly or partially immersed in peroxide in small test tubes or flasks which were loosely covered to prevent the entry of dust. For tests a t 50' C. the peroxide was contained either in test tubes

INDUSTRIAL A N D ENGINEERING CHEMISTRY

312

TABLE 111. DISTILLATIONOF 10 11 12 14 15 16 17 350 350 354 350 350 350 350 34.0h 31.9h 31.4h 31.8b 40.6 29.Ob 28.38 231 291 269 194 162 168 158 0 6.5 17.3 6.0 11.3 1.0 0.7 46 23 129 131 51 57 79.6 82.3 67.2 63.5 12.2 5.8 . . . . . . . . . . . . 93 . . . . . . . . . . . . . . . . . . 58.4 116 8 57 3 3 115 30 78.0 98.8 96.3 88.9 98.8 79.7 97.6

Run No. Grams charged % H202 1st cut, grams % Hz02 2nd cut, grams

... ...

% Hi02

3rd cut, grams % HzOz Residue, grams % H202 Recovery

desired Conditions 1st cut Temperature, C. Room Flask, start Flask, end Column, s t a r t Column, end Pressure mm. H g Av.ratekistn.,ml./min. Conditions 2nd cut Temperature, C. Flask end C o l u r h , end Pressure, mm. H Av,ratedistn.,m&/min. Conditions 3rd cut Temperature, * C. Flask, end Column, end Pressure mm. H g ~ vrate . kistn., ml./min. 5 Water-jacketed column.

282 119 63 56.3

256 113 91 75

...

229 97.2 120 101

224 192 233 249 93.3 92.4 94 99.3 ' 102 104 100 88 73.4 92.8 98.5 89

18

19

20

... ...

261 107 92 81

259 106 87 81

26 31 45 25 29 10 1.4

28 30 42 28 29 10 1.2

28 30 47 25 33 10

56 40 7 2.6

54 33 10 2.0

55 38 20 1.0

56 40 10 1.6

53 43 10 0.9

49 38

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

59 39 51 , 5

60 46 10 2,3

58 48 1;

...

*2791 . 9

62 37 6 3.0

60 37 5

38 7

40

50 26

GO

........

. . . . . . . . . . . . . . . . . b

Superoxol.

0

3i7" 68.4

245 488 596 100 98.4 100 88 206 253 83.4 100 98.9 71.0 85.4 88.3

25 43 50 32 34 30 1.0

... ... ... ... ..* ...

24

250

2ia

30"

852 850 8.50 2218 30.16 30.1b 34.9c 34.20 367 370 350 1042 3.7 3.0 3.0 2.8 156 122 94 168 10.5 3.8 3.7 5.2

. . . . . . . . . . . . . . . . . . .

25 49 58 31 35 30 1.1

31 58 22 35 6 2.6

21

350 700 357 352 31.66 30.8b 30.9b 24.1b 207 ?05 201 448 Trace rrace 0 7.5 72 67 45 34.0 3 1 . 6 29.8 30 38 74.8 77.3 46.5 38 Si11 2 4 i ' 96.8 9 8 . 9 81.1 7 0 . 1

43 51 25 31 7 2.0

... ... ...

. . . .

HYDROGEN PEROXIDE '

.....................

. . . . . . . . . . . . . . .

26 67 22 30 7 1.4

Vol. 38, No. 3

1.3

10 1.2

29 30 41 23 33 10 1.6

... ...

... ...

352' 4ii' 67.3 70.5 589 99.2 252 98 92.7

546 92.0 298

25 32 39 27 26 20-10 1.7

24 40 40 22 23

24 34 41 22 24

10

10

43 30 10 1.7

45 25 10 1.3

2.1

100

94.9

31" 2200 34.2c 1077 2.3 177 6.1

.... ....

6%'

72.4

930 76.5

1446 99.2 754 99.5 95.0

1436 99.0 748 99.4 95.3 30 32 43 25 28

1.6

27 33 41 24 27 10 2.2

45 25 10 1.2

44 29 10 0.8

47 28 10 1.4

.. .. .. .. ... .. .. .. .. .. .. .. .. . .. .. . . .. ... .. .. . . . ....................... .......................

BUFFALO ELECTRO-CHEMICBL COJIPANY. The first step is to immerse in 0.5% sodium hydroxide for 1 hour, then wash with water. The second step is to pickle in 35% sulfuric acid for 1 hour and wash with water. PENSSYLVANIA SALT ~IANUFACTURING C o m A m . In the first step 102 pounds of 6% sodium hydroxide are made up with tap water and placed in the drum, which is rolled for 5 minutes. The solution is then transferred to a second drum. Twenty-five t o thirty drums can be treated with this solution and are then

TABLE Iv. SPECIFICATIONS OF ALUMINUM, STEEL, ,4ND GASKET M.4TERIALS Baker & Adamson 99.0-99.5% AI 98.8% Al, 1.2% hIn 91.2% Al, 2.5% M E , 0.25% 90% Al, 10% Iblg

2 70 2 68 2 69 2 67 2.53

ci.

0.08% C 2.00% M n 0.50% Si, 18-20% Cr, &io% Ni, 0&5% P, 0.025% S 0 1 5 7 C 11 5-13 a % Cr 0:35+ C' 25-30oJd Cr 0.10% C: 2.75% Mo, 17% Cr, 13% Xi 0.50-0.15% C G A 0 K E T 5 f A T E R I A L S A N D COATIKG8 Garlook Bitan cup leather carbon black) Garlock sheet gasket No. 7790 (Buna S Koroseal type 116 (clear) Xoroseal type 117 (black) Lumarith. Celanese Celluloid Corp. Saran tubing (clear) Saran tubing (black) Ohiokote No. 37, Ohio Corrugating Go. Phenol-formaldehyde coating, CWS specification 196-13 1-207 8s 410 SS 446 Croloy 16-13-3 Cold-rolled WD1010

*I

7.91

?

7:90 7: i s

+

TABLE

v.

STABILITY

OF

HYDROGEN PEROXIDE DRUMS

Drum 35 , -Drum Date Days % HzOz Temp., ' C. Date 7 May 0 88.9 24 May 21 May 14 89.6 50 31 May 22 May 1 89.6 66 14 June 28 May 7 89.2 65 28 June 65 11 June 21 89.1 65 25 June 35 88.7 Analyzed Maroh, 7 90 1% HzOs Analyzed March Z?, 90.2% H z 6 . /

..

2.6

Beoco.

dosed with Koroseal Bunsen valves or in Erlenmeyer flasks covered with inverted beakers. Before testing, steel pieces were pickled for 10-20 seconds in 10% sulfuric acid a t 80' C. to remove scale. The following standard methods of pickling aluminum containers to be used for storing peroxide were adapted t o aluminum test pieces. DU PONTC o m A m . The three methods used by Du Pont (4) are: 50% nitric acid for 16 hours a t room temperature, 35% nitric acid overnight a t room temperature, and 50 t o 100% nitric acid for 9-16 hours.

A1 A1 2 s -41 38 AI 525 AI 220 T-4 STEELSAMPLES SS 304

10

IN

,--MERCURY

ALUMINUJI 8UL8 BLOWN %"oD. 7 GLASS TUBING

9 a t 65' C.6Days % Hz02 0 90.3 7 90.1 21 89.4 36 89.0

m

%o.0.

Figure 1 .

Pressure Development Apparatus

INDUSTRIAL AND ENGINEERING CHEMISTRY

March, 1946

313

differently when stored in various sizes of Pyrex containers

REACTIVITYTESTSON CONCENTRATED PEROXIDF.proved that differences in stability of peroxide due to the size WITH METALSAND METALLIC COMPOUNDS of the glass container are not great, but there is a n inclination MATERIAL ADDED RESULT towards greater stability in the large containers. This means Nickel metal, shot No immediate reaction, slow gas evolution on that marked instability, noted with small volumes and metal standing Silver, sheet Gas evolution, slow at first and rapidly becoming test pieces, is largely due to the presence of the metal rather than violent, then slowing to a rapid, apparently constant rate tb the glass. The stability of concentrated peroxide in Pyrex Lead, silvepfree granules Violent reaction is good even up t o 100" C. At this temperature stabilized conZinc. shot Similar to nickel Lead peroxide Explosive reaction centrated 86.7% peroxide decreased only 6% in one week and Cobalt Medium-slow reaction No reaction Magnesium, ribbon only 1%while held at 50" C. for 11 days. All08 Very slow gas evolution The superior stability of the material prepared by concentraFez08 Very slow gas evolution, slightly more than Alz'Oa Antimony, powder Very slow gas evolution ting dilute peroxide as compared to that of the purer product Cadmium, stick Similar to nickel KzCrOi Immediate rapid reaction, with formation of a obtained by distillation of dilute peroxide is attributed to the blue compound, probably perchromate presence of stabilizers in the former. (The very pure Becco No reaction Tin, foil NaOH, pellet Medium-slow gas evolution, apparently at a conproduct contained 2 p.p.m. of added stabilizer.) stant rate Mercury Medium gas evolution with formation of red oxide Data show that the Becco product is more stable in 30-gallon Solder None at first but violent reaction on second exDoaluminum drums than is indicated by laboratory tests in glass. sure Tinned copper wire Very slow reaction The superior stability in aluminum may be due to several factors, Chrome1 wire Very slow reaction Ver slow reaction Platinum wire such as differences in ratio of surface t o volume, differences in 81ig t reaction Copper wire

TABLEVI.

x

rinsed with t a p water. I n the second step the drum is rolled for 3 minutes in a solution made up as follows: 14 lb of 70 HNOa (11.3% by wt.) 10 lb: of 48% H F (8.1% by wt.) 100 lb. of tap water (80.6% by wt.)

-

124 lb.

The drum is emptied and washed with tap water, and is then ready for filling with hydrogen peroxide (100 volume). Table IV lists the aluminum and steel samples used in corrosion tests, as well as the gasket materials and coatings. STORAGE OF CONCENTRATED PEROXIDE

Practice has been to ship and store peroxide in 30-gallon drums of aluminum, whose minimum purity was 99.6% to prevent undue reaction with peroxide (3). Table V shows that concentrated peroxide may be stored in such containers up to temperatures of a t least 65 ' C. Peroxide drum 3 was placed in an oven and kept a t 50" C. for 2 weeks; then the temperature was raised to 65 " C. Shortly thereafter drum 9 was put into the oven a t 65 " C. The results of these tests are given in Table V. Four cans made of 25 aluminum were procured for use in intermediate storage and transportation of concentrated peroxide. They were cylindrical, held 3 gallons each, and had siphon arrangements of 2s aluminum tubing that could be put on in place of their aluminum caps. The cans were pickled according to the Pennsylvania Salt Manufacturing Company procedure. Then 35% technical peroxide (Becco) was stored in them for approximately one month at normal temperature. During this time the peroxide content did not change significantly although there was some pitting of the aluminum. This effect was not severe except in the case of two of the siphon tubes. Two of the four cans were emptied, washed out well with distilled water but not dried, and filled with concentrated peroxide. The cans were stored in the warehouse and volumetric analyses made at intervals t o detect any large changes. At the end of 30 days, gravimetric analysis showed that can 1had decreased 0.8% (89.5 to 88.5%) in peroxide content and can 2 had decreased 1% (89.5 t o 88.5%). Therefore the 2s can5 are considered suitable for intermediate storage and transportation. The stability of concentrated peroxide in Pyrex laboratory ware was also determined as a control for other tests with various mateyjals. It was found that, if stabilizers are present, peroxide may be stored at 50" C. in Pyrex without undue deterioration, Although 90% peroxide alone i n a test tube was quite stable, in the presence of metal test pieces a small volume (5 ml.) of the material decomposed completely in less than a week at room temperature. A test to determine whether peroxide behaves

the nature of the surfaces involved, the magnified effect of contamination of a small volume of peroxide, and the opportunity for contamination in the laboratory samples which are more frequently handled. PEROXIDE REACTIVITY W I T H VARIOUS MATERIALS

Each of the materials listed in Table VI was separately added to a test tube containing 10 ml. of concentrated peroxide. Tho effects of these materials was visually noted, and samples of those that appeared to cause no reaction were placed in 150 ml. of concentrated peroxide in covered 250-ml. Erlenmeyer flasks. The results (Table VI) indicate that several of the materials might be used t o decompose peroxide rapidly in situations where this effect is desired. Lead dioxide and potassium chromate were outstanding in this respect and deserve further study. Table VI shows further that, of the metals tested, nickel, cadmium, antimony, cobalt, zinc, andpagnesium showed ~~

~~

TABLEVII. STABILITY OF CONCENTRATED PEROXIDE WITH VARIOUSMETALS

cF

Peroxide Ni Zn Room Temperaturea

% peroxide

0 day 1 day 2 days 3 days 4 days 6 days 8 days 10 days 12 days 14 days 16 days 23 days 30 days 37 days . 43 days Weight, grama Initial Final Change

89.5 87 87 86 85 85 85 85 85 85 54 83 81.0 73.4 67.5

.

5.2854 5.2821 -0,0033

89.5 89 88

88 87 87 87 87 87 87 87 87 86.9 87.4 87.1 4.7135 4.7012 -0.0123

89.5 88 88 88 88 88 88 88 88 88 88 88 87.5 87.3 86.6 5.1887 4.9266 -0.2721

Mg

89.5 87 87 87 86 85 84 83 83 82 82 80 78.2 71.9 67.0 0.5314 0.5117 -0.0197

Temperature, 50' C.

% peroxide

89.0 89.0 89.0 89.0 0 day 89.0 89.0 88.4 88.0 1 day 88.4 89.0 52:6 88.4 , 3 days 86.9 89.0 88.4 82.0 4 days 86.0 88.4 88.4 78.4 5 days 79.4 88.4 88.0 78.4 $,days 79.1 89.1 43.5 88.3 12 days 71.8 87.4 88.0 6.9 17 days 40.6 86.9 84.6 31 days 48.4 2.1 Change 8910 4.4 Weight, grams 5.0471 0.4395 6.0373 5.0006 Initial 4.9732 0.4477 6.0474 4,9968 . Final Change -0.0038 +0.0101 -0.0739 +0.0082 a With cobalt the Concentratedperhnide decomposed in about an hour and with antimony i t decomposed on standing overmght.

I N D U S T R I A L A N D E N G I N E E R I N G CHEMISTRY

314

TABLBVIII. EFFECTOF PEROXIDE (5 ML.) MATERIALS AT 50" e.

ON

VARIOUS

Final Material

Time, Days

None 52S'/rH A1

12 3

8 Baker a n d Adamson A1 SS 446

SS 304 Lumarith resin Croloy 16-13-3 Hastelloy A

None 52S'/rH AI Baker and Adamon

AI SS 446

SS 304 Lumarith Croloy 16-13-3 Hastelloy A

70

Peroxide Remarks 30% Peroxide (c.P.) 11.2 ......... 0 Smoky appearing surface 0 Dull white surface

3 8 8 12 8 12

1.1 0 0 0 0 0

3 8 8

1 .08 27 0

12 8

12 10 8

33.8 34.2 33.0 35.2 33.0

8

18.5 15.4 3.5

8

.........

......... ......... .........

White, opaque

......... ......... ......... .........

90% Peroxide None 52S'/rH d l Baker and Adamson A1 SS 446 SS 304

Lumarith Croloy 16-13-3 Hastelloy A

0

8 8 12

0 56.8

3 8 8 12 8 12 3 12

48.8 1.0 0 0 0 0 84.9

8 12

....

..........

1.0387 1.0391

$0.0004

1.0372 1.0397

+0.0026

0.8287 0,8267 1.4323 1.4638 1.5186

0.8284 0.8277 1.4324 1.4644 '1.5179

-0.0003 +0.0010 +0.0001

1.4863 1.4870 0,4952 0.5570 0.4674 0.5107

$0.0007 $0.0618 +0.0433

+0.0006

-0.0007

Appearance unchanged 2.9025 2.9028 0.0000 0 Appearance unchanged 2.8305 0 Somerust 3,1713 3 : i 7 i 7 +0:0604 0 Some rust 3.1425 3.1423 -0,0002 35% Technical Peroxide 35.5 ......... .... .......... 33 . O ......... 0.7831 0.7829 -0.0002

3 3 8 3 8 3

Metal spotted Metal spotted Yellow surface Yellow surface Yellow surface Appearance unchanged hlilky color

Wt. of Test Piece, Grams Initial Final Loss

e o 0

...

3

0.05

8

0

......... ......... ......... ......... ......... ......... ......... ......... .........

Disintegrated Sample dissolved

.........

Not enough sample Some rust in soln. Some rust in soln.

0.7912 1.4345 1.4988 0.4765 0.4682

0.7911 .-0.0001 1.4349 $0,0004 1.4996 +0.0008 0.5342 + O . 0677 0,5250 $0,0568

2.8648 2.8650 3,0334 3.0335 3.0736 3.0736

....

$0,0002 $0.0001 0,0000

..........

0.7701 0.7701 0,8903 0.8088

0.0000 -0.0015

0.8200

0.8421 1.4791 1.4516 1.5066

1.3202 0.4798

..........

Vol. 38, No. 3

TABLE IX. DATAON ALUMINUM 2 s IN OPEN TESTTUBES AT ROOMTEMPERATURE" Peroxide Used, %a 30 30 35 (tech.) 35 (tech.)

Ivt. Of 2s

Initial 1.0048 0.9795 0.9884 0.9442

Final 1.0030 0.9796 0.9885 0 9445

Grams Change -0.0018 0 +0.0001 +0.0003

Time, Days

Penetration, In./Month

Final,% Peroxide

28 32 28 32

0.000057 None None None

18.9 15

2s: 5

a Test pieces were 0.20 X 0.70 X 2.90 cm. (5.5 s q . cm.) and were given

the Becco pickling treatment. Density of 29 A1 = 2.69 g./cc. Original 30% peroxide = 27.3%; original 35% peroxide (tech.) = 34.9%. Volume of peroxide used = 5 ml.

TABLEX. ST.4BILITY

O F CONCEN'PRATBD PEROXIDE (5 ?rlL.) A T R O O M TEMPERATURE I N PRESEKCE O F ALUMINUM 529'/4H IN COVERED TESTTUBES

Test h-0. Duration, days Initial wt. of test piece, gram Final wt. of test piece, gram Wt. change of test piece, gram Final eoncn. of peroxide % Original concn. of peroxihe, %

2 26 0.8083 0 8092 f0.0009 0.0 90.3

1

14 0.8058 0 8065 -0 0003 84.3 90.3 ~~

TABLE XI. STABILITY OF 89.27, PEROXIDE (5 ML.) IN PRESENCE OF STEELIN SMALL TESTTUBESAT ROOMTEMPERATURE Test No. A1 A2 B1 B2

c1

c2 D1 D2 El E2 F1 F2 F3 F4 F5 F6

Type of Steel ss 12 ss 12 SS 304 SS 304 SS 446 SS 446 SS 18-8 SS 18-8 W D 1010 W D 1010 None None None None None None

Initial 1,0583 1.0640 2.7784 2.5782 1.4424 1.4572 2.8707 2,8583 2.8791 2.8203

.... .... .... ....

.... ....

Weight, G r a m Final Change 1.0589 + O . 0006 1.0641 +O.OOOl 2.7780 -0.0004 2.5781 -0.0001 -0.0002 1.4422 1.4572 0.0000 2,8706 0.0002 2.8581 -0.0002 2.8791 0.0000 2.8189 -0.0014

-

.... .... .... .... ....

....

...... ...... ...... ......

...... ......

Time, Days

Final 70 Peroxide

7

0.00 0.09 1.6 0.00 1.4 0.0 0.0 0.0 0.0s O.OQ 89.2 82.2 89.0 90.3 85.2 83.8

10 7 10

7

10

7

8

7 7 5

10 17 19 30 37

Test pieces were rusted.

0,4476 . . . . . . . . . . 2.8109 2.8108 -0.0001 2,8931 2.8927

-0.0004

3,0438 3.0429

-0.0009

2.8824

-0 0001

2.8823

the least decomposition of peroxide; hence they could probably be tested quantitatively. Data for these metals are given for room temperature and 50" C. in Table VII; cadmium and zinc caused only little decomposition of the peroxide but were thernselves attacked. On the basis of these tests none of the metals should be considered for use as storage containers. Tables VI11 to XVI summarize other preliminary and screening tests. These tables show that peroxide has little corrosive action on the metals tested (except cadmium and zinc), even though the peroxide may be almost completely decomposed by the contact. An increased stability of the stabilized peroxides is apparent even in contact TTith metals. A later section will show this same stabilizing effect in the absence of metals. Tables VI11 through XIV list data on the behavior of aluminum and stainless steel samples in contact with 5 ml. of peroxide. I n all cases the extreme instability of the peroxide is due to contact with the metals, particularly stainless steel. The exception is peroxide made by concentration (Table XII), and this is attributed to the presence of more than the usual amount of stabilizer. The addition of still more stabilizer (Table XIII) may raise the concentration too high. It must be remembered in this connection that the surface-volume ratio of test pieces to peroxide was ten times that of the standard 30-gallon peroxide drum. Table XV shows that Koroseal, Garlock 7790, and Saran tubing were little affected a t room temperature by 35% technicalgrade peroxide. The peroxide was only slightly affected by con-

tact with these materials. Table XVI gives the results of tests on the stability of these plastics in concentrated peroxide. Polyethylene (Plax) was not, visibly affected after 9-day contact with concentrated peroxide a t 50" C. Cenco Hyvac oil was not visibly affected after 1.5-hour contact with concentrated peroxide a t 50" C. Table XVII is representative of the type of data obtained from pressure measurement carried out in the apparatus earlier described (Figure 1). Although this method gives a sensitive means of following small chanyes~in the decomposition of peroxide, t,he extent of the changes in such small containcrs is greater t,han can be conveniently measured in this apparatus and are greater than actually occur in larger containers. Therefore this type of test was discontinued. However, the corrosion data obtained in these tests are consistent with other data. A test piece of aluminum 25 (pickled in 0.5% sodium hydroxide followed by 3570 sulfuric acid) was dipped into 50 ml. of concentrated peroxide and then suspended above the liquid on a glass hook. The concentrated peroxide was in a 125-m1. Erlenmeyer flask covered with a beakcr. The system was stored in the oven a t 50" C. and inspected a t intervals as follom: 1 day 3 days 2 1 days

P a r t of one side darkened Slightly darkened, no pitting Black surface and deep pitting

The original test piece weighed 0.9231 gram, and a t the conclusion of the test (21 days) it weighed 0.9238 gram. The concentrated peroxide had almost completely deeomposed during the test; only 0.46 gram of peroxide per liter remained a t the end. Table XVIII shows that concentrated peroxide does not affect the mirror finish on stainless steel but may form a deposit on aluminum, even though the peroxide itself may decompose.

INDUSTRIAL AND ENGINEERING CHEMISTRY

March, 1946

TABLE XII. STABILITY AT 50' C. OF 68.3% PEROXIDE (5 M L . ) ~ IN CLOSED TESTTUBES Test Weight, Grams % Peroxide Piece Initial Final Losn 7 days 14 days SS 304b 2.1177 2.1177 0.0000 57.1 41.3 SS 3041, 1.3380 1.3379 0.0001 58.1 42.3 AI 97.7YO0 0.724: 0.7239 0.0005 51.0 9.5 None ,*.. .... 64.6 59.6 *.., 64.7 60.5 None a Pre ared b concentration of 30% peroxide (superoxol). b Pick)ed in & & 0 4 . Becco treatment.

.... ....

AT 50' TABLE XIII. EFFECT

c. ADDING 100 P.P.M.

No.

STABILIZER

(Na8P04)TO 68.3% PEROXIDE (5 ML.), PREPARXD BY CONCBNTRATING 30% PEROXIDE

Wt. of Teat Piecea, Grams Test % Peroxide Metal 7 days 14 days Initial Final Change 55304 51.6 30.6 2.0380 2.0380 0.0000 B SS304 58.1 43.1 1.2755 1.2754 -0.0001 57.6 30.2 0.7214 0.7210 -0.0004 C 99.7% A1 D None 63.8 57.8 E None 63.9 57.8 .............. Teat pieces were 0.20 X 0.70 X 2.90 cm.

Teat No. A

..............

a

TABLEXIV. TESTOF

STAINLESSSTEEL 446 I N OPEN TEST TUBES AT ROOM TEMPERATURE

PeneFinal Weight*, Grams Time tration Yo Per(5 Mi:)" Initial Final Change Day; In./Md. oxide 14 None 20.6 1.4483 1.4484 t 0 . 0 0 0 1 30 30 1.4098 1.4100 +0.0002 28 None 9.9 A2 1.4328 1.4330 +0.0002 14 None 29.8 B1 35 (tech.) 1.4368 1.4366 -0.0002 28 None 30 €32 35 (tech.) 5 Original 30% peroxide = 27.3%; original 35% peroxide (tech.)

Test

No. A1

Peroxide Concn., % (5 Ml.)"

% Per-

Koroseal 117b 0.8946 0.8820 -0.0129 0.9039 0,8903 -0,0136 0.9497 0.9361 -0.0136 0.9162 0.9019 -0.0143

28 33 28 33

19.7 22 27.4 29.2

28 33 28 33

24.7 26.5 34.3 35.0

28 33 28 39

24.0 23.5 34.7 35

Weight, Grams Final Change

A1 A2 B1 B2

30 30 35 (tech.) 35 (tech.)

A1 A2 B1 B2

30

35 (tech.) 35 (tech.)

Garlock 7790E 0.2462 0.2578 +0.0116 0.2429 0.2580 +0.0151 0.2398 0.2617 $0.0219 0.2392 0.2629 $0.0237

A1 A2 B1 B2

30 30 36 tech) 35 {tech:)

Clear Saran Tubingso 0.5117 0.6818 +0.0001 0.15162 0.5139 -0.0023 0.4986 0.4986 0.0000 0.4909 0.4909 0.0000

30

Final

Time, Daya

Initial

Black Saran Tubingc 30 0.7738 0.7743 D1 -I-0.0005 D2 0.7896 30 0.7878 -0.0018 El 36 tech.) 0.7288 0.7273 -0.0015 E2 35 {teeh.) 0.7272 0.7261 -0.0011 Original 30% peroxide 27.3%, original 35% peroxide b Test pieces were 0.26 X 0.70 X 2.9 cm. Test pieces were approximately 0.1 X 0.7 X 2.9 cm.

-

oxide

28 7.1 33 14 28 29.3 33 28 (tech.) = 34.9%.

Peroxide

conon%

-

34f2U test pieces (0.10 X 0.70 X 2.90 om., 4.78 nq. om.) were piokled in 10% HzSO4 a t SOo C. Leather, even when covered with Silicone stopcock lubricant, is badly attacked in a short time: Hours of

Contact 0 1 2

'

TABLEXV. TESTSON PLASTICS AT ROOMTEMPBRATURE IN OPENTESTTUBES Test

....

315

% Peroxide by Wt. 90.1 89.6 89.5

Hours of Contact 3 4

% Peroxide by Wt. 89.2 89.3

Ploxite disks were physically unaffected by immersion in conoentrated peroxide a t room temperature for 21 days (Table XIX). The disks accelerated the decomposition of the peroxide. The disks of greater porosity caused greater decomposition. Table X X shows that coating cold-rolled steel with Silicone stopcack grease retards but does not stop the decomposition of peroxide by steel. STANPARD TESTRESULTS. One hundred fifty milliliters of peroxide in a 250-ml. Erlenmeyer flask was considered a large enaugh sample t o give significant results in terms of general storage, yet small enough for convenient laboratory handling. Tables X X I t o XXVI give data obtained in this manner. A purity of at least 99.6% aluminum is necessary for satisfactory stability, but higher purities have no further beneficial effect, (Table XXI) , No significant differences in corrosion were found due t o variation in purity of the samples. Tables X X I I and X X I I I show 25 aluminum to be inferior t o 99.770 and 52s aluminum. This is in agreement with Table X X I since both 99.7% and 52s aluminum are free of such impurities as iron and eopper which 2s aluminum contains. The 'presence of small amounts of magnesium in aluminum is not harmful, and the differences among aluminum samples are due to certain specific impurities. Table XXIV gives the data for the stability of peroxide stored in contact with pure tin, tantalum, and Silicon% stopcock lubricant. These materials compare favorably with high-purity aluminum (Tables X X I and XXIII). Table XXV shows that the first contact of peroxide with stainless steel produced rapid decomposition. It was thought that the surface had become active; therefore, the flask and test pieces were washed with distilled water, and the test was re-

TABLE XVI. STABILITYOF PLASTICS WITH 90.2% PEROXIDP (5 ML.) IN CLOSEDTESTTUBES Teat

No. A1 A2 A3 A4 B1 B2 B3 B4

Temp., O

C.

Time, Days

Final % Peroxide

Initial

Weighta, G r a m Final Change

25 25 50 50

14 22 14 22

Koroseal 117b 63.7 0.6749 57.6 0.7289 51.7 0.7240 40.3 0.8289

0.6894 0.7715 0.7160 0.7996

+0.0145 +0.0426 -0.0180 -0.0293

25 50 50

14 22 14 22

Korosoal 116b 71.2 0.6047 56.2 0.6000 4.7 0.5103 14.6 0.5836

0.6031 0.5987 0.5074 0.5771

-0.0016 -0,0013 -0.0029 -0,0065

Garlock 7790C 86.7 0.2233 0.2329 $0.0096 c2 83.4 0,2194 0,2190 -0.0004 c3 84.8 Disintegrated c4 84.8 Disintegrated Saran, C'leard D1 25 14 77.3 0,5006 0.5005 -0,0001 D2 25 ' 22 77.8 0,4792 0.4792 0.0000 D3 50 14 21.8 0,4968 0.4945 -0.0023 D4 50 22 23.8 0.4869 0.4837 -0.0032 a A proximately 0.2 X 0.7 X 2.9 om. or 5.5 sq. om. b B h t e r a formed on the surface of Koroseal 117 both a t room temperature and.50' C.: type 116 tended.to separateinto iayers. A slight blue color appeared in the peroxide when Garlock was added. After 4 days a t 50' C. the samples completely disintegrated. After 14 and 22 days the samples a t room temperature had a cracked surface which was easily abraded, and the materia1,was lens flexible. The peroxide was more stable in contact with this material than with the Koroseal. d Saran appeared to be the least changed.

c1

25 25 50 60

14 22 4 4

started with fresh perodde to determine whether the rapid decomposition would continue or even accelerate. Table XXV indicates that the reverse was actually the case, and the peroxide showed stability of the order found with aluminum. When the metal was alternately exposed to liquid and to air, good stability resulted (Table XXVI), similar to that of the steel samples during the second treatment. This shows that while, in general, peroxide may be safely kept in contact with steel, it is important that the steel surface be in proper condition. Low-carbon steel is a n impractical material because it is difficult to maintain it with any given surface condition. Even a slight amount of rust greatly accelerates decomposition of the peroxide. Since stainless steels are resistant to ordinary surface attack, they tend to maintain a proper surface condition, once it is obtained. Test pieces (5.0 X 1.4 X 0.1 cm.) of aluminum were three fourths immersed in 150 ml. of concentrated peroxide in a 250ml. covered Erlenmeyer flask and stored a t 50 O C. The samples

INDUSTRIAL AND ENGINEERING CHEMISTRY

316

Vol. 38, No. 3

centrated peroxide. Three test pieces, pickled by the Becco method, were used in each flask. The data (Table XXII) show that none of the aluminum pieces TEMPERATURE were appreciably attacked, but that the concentrated Test No. A1 A2 I31 B2 c1 c2 D RIetal'J xone sone jasl/2ri ~ Z S I / ~ H 5 2 ~ 1 , ~ 1 1; J ~ I / , I I ? ~ I / J I peroxide was niorc btable in the presence of 99.7% and Treatment Becco Becro JIN03b I l S 0 , b ITNOIC 52S1/dH aluminum than in the presence of the 2S1/4H Pressure, atm. aluminum. Another test (Tadle XXIII) a t BO" C. 1 . 0 1 . 0 1 . 0 1.0 1.0 1.0 0 hr. 1.0 with the same metal t y p c s and conditions showcd the 1.1 1.0 1.2 1.2 1.2 3 hrs. 1.0 1.2 1.3 1.1 I .0 1.1 1.3 4 hrs. 1.3 1.3 same results. 5 hrs. 1.0 1.0 1.2 1.4 1. B 1.4 1.4 1.1 5.2 4.6 2.2 2.4 29 hrs. 1.2 4.7 Pieces of tin and tantdurri arid 1.0-gram samples of 8.1 6.3 2.2 4.3 6.7 1.3 1.2 45 hrs. Dow Silicone stopcock grease were placed separately in 9.2 1.2 49 hrs. 1.4 0.8 2.3 4.6 7.0 5.1 10.0 1.2 8.1 2.6 53 hrs. 1.4 7.8 150-ml. portions of concentrated peroxide in covered 12.6 9.7 &.4 9.2 79 hrs. 1.5 6.3 1.3 11.9 13,J 2.7 9.6 87 hrs. 1.6 7.8 1.4 250-ml. Erlenmeyer flasks. The flasks were stored a t 2.5 103 hrs. 1.8 8.5 15.6 10.6 14.5 1.4 the temperatures indicated in Table XXIV and the 2.7 1.5 111 hrs. 1.8 9:s 16,'8 ii:9 16:Y 2.6 128 hrs. 2.0 1.6 peroxide was analyzed a t intervals. Keither the tin 11.2 18.4 18.5 2.7 1.8 1 3 . 0 151 hrs. 2.1 nor the tantalum \vas attacked; the concentrated per175 hrs. 2.4 1.9 .. 3.5 .. .. .... ?: . 3 .. 3.9 .. .. 223 hrs. 3.2 oxide was unaffcctcd by thcse mctals and did not de.. .. 2.6 4.1 .. .. 247 hrs. 3.3 compose more n i t h the Silicone than with glass alone. 2.6 4.1 .. .. .. 271 hrs. 3.4 2.9 4.4 .. ~. .. .. 294 hrs. 3.9 The data in Table XXV were obtained unkier the .. 3.1 4.7 318 hrs. 4.1 .. .. 5.1 .. .. 3.3 .. " . 342 hrs. 4.6 following conditions: Two vveighrtl steel test pieces 3.G 4.4 .. .. .. .. 366 hrs. 5.4 (0.20 X 0.70 X 2.90 em. each, with 11 sq. em. total 5.0 .. .. .. .. 396 hrs. 6.0 3.9 3.8 .. .. .. 4.1 6.5 .. 410 hrs. arcs) werc suspended on a glass rod in an Erlenmeyer 5.1 440 hrs. 6.7 .. .. .. 4.3 .. .. .. 7.1 4.4 .. 482 hrs. 7.6 flask contn ininr- 150 ml. of roncentrated oeroxide .. 0.7wci 0.8206 0.7764 0.8158 0.9558 The actual initial concentration was 90.2%. The teat, Initial wt., g. .. , , 0.79S7 0.8205 0.7757 0.8157 0.9552 Final wt., K. .. . , +o.nooi -o,oooi -0.0007 -0.oooi -o.oooi pieces were totally irninerseti i n theliquid, and the flask Wt. change, 6. .. 84 87 87 89 87 88 Final % peroxided 89 was covered with a 150-ml. beaker so that the oppor13.1 12.7 12.7 1 1 . Y 12.6 13,8 Vol. of tube, ml. 13.2 tunity for cvaporation was negligible. The flasks were Test pieces were 0.20 X 0.70 X 2.90 cm. or 5 . 5 s q . em. b Concentrated C.P. HNOj for 3 hours a t room temperature. stored a t room temperature, and a 1-ml. sample of per0 Fuming HNOs (sp. gr. 1.50) for one week a t room temperature. oxide was withdrawn for analysis a t the times indicated. d Calcqlated from pressures developed, assummg oxygen to be solely reJponsible for pressure Increase. On the seventeenth dav all of thc flasks exceut the controls 0'1 and F2) were eniutied of oeroxide. and a new charge of 160 ml. of 89.5% peroxide was added after were given the Becco treatment prior to use. Table XXI 1,he A i d s and test pieces ITere washed with distilled water. The steel pieces were originally nashcd with toluene, acetone, and shows the variation of peroxide composition with time. water, and pickled for about 15 seconds with 10% sulfuric acid at Aluminum test pieces, 0.20 X 0.70 X 2.90 em., werc sus80" C. They byere then washed with water and acetone, dried pended in 150 ml. of concentrated peroxide in a 250-ml. Erlena t 110" C., and weighed. At the conclusion of the test, the steel meyer flask, covered with a 150-ml. beaker. To the bottom of pieces were washed with water, dried a t 110O C., and weighed. the beaker was sealed a glass rod having a hook on the free end To determine the effect of alternate exposure to concentrated by which the test pieces were three fourths immersed in the conTABLEXVII. EFFECTOF METHODOF TREATING A L u x I N m i 52S1/4H ON DEVELOPMENT OF PRESSURE BY 90.39% PEROXIDE (5 ~ I L .AT ) ROOM

. I

I .

(1

TABLEXVIII. EFFECT OF CONCEXTILATED PEROXIDE ON MIRROR-FINISHED 25 ALUMINUX.4ND STAINLESS STEEL 304 [One sample of each metal covered with concentrated peroxide (7 in1.1, stored a t BOo C., and observed daily] Days .Metal Results 2 SS Surface unaffected peroxide bubbling strongly, liquid nearly gone, trdsferred t o new tubes with fresh concd. peroxide Surface unaffected, slow evolution of gas A1 3 SS Surface unaffected, strong evolution of gas Surface misted, slow evolution of gas A1 SS Surface unaffected peroxide analyzed O%, replaced with 4 fresh concd. periside but only partly immersed dl Surface misted, peroxide analyzed 11,8%, replaced iriih fresh concd. peroxlde but only partly immersed 5 SS No change in appearance, slox gas evolution No change in appearance, slow gas evolution A1 G SS No change in appearance Slight deposit on surface in vapor A1 8s No change, peroxide analyzed 0% 7 Depovit heavier, peroxide analyzed 3.5% A1 OF ALOXITEDISKSON 89.Gyh PEROXIDE TABLEXIX. EFFECT AT Rooni TEMPERATUREa

Test No. Aloxite No. Size, in. Permeability, No.

% peroxide 7 days 14 days 21 days

A1 100-28 l1/z X

l/z

5

85.7 82.2 77.9

A2 100-28 li/z X ' / z

B1 100-28 la/( X

5

5

86.0 80.7 74.4

85.6 80.1 72.4

B2 100-28 3/s

13/4

x

5

86.6 62.7 78.4

3/1

85.1

78.4 66.9

T h e disks had been ex osed t o concentrated peroxide for one week, then washed with water, a n z d i i e d a t 110' C. before use. The disks and 150 ml. o f peroxide were placed in covered 260-mi. beakers. 0

TREATXENT None

A.

E.

Coated with Silicone stopcock grease Soaked in niixt. of 50% by wt. each of abs. methanol and 8 5 % HjPOn until a gray Burface formed D. Treated as C, then coated with Silicone E. Coated with liquid petrolatum

C.

F. Dipped in dibutylphthalate

OBSERVATION Moderate evolution of medium-sire bubbles Slow evolution of large bubbles Very rapid evolution of fine bubbles; 2 days later concd. peroxide was almost gone, and metal rusted Same as R Initial slow evolution of small bubbles gradually increasing t o moderade evolution of medium-size bubbles Same as E

TABLE XXI. EFFECT O F PURITY OF ALUMINUM Oh' DECOXPOSITION OF 87.2% PEROXIDE SOI~UTIONS Test piece

7"A l a

3/ a e.:

c1

220-28 2 x 3/4 1

85,s 79.9 70.9

OB' SURF.4CE TREATMENT OF COLD-ROLLED TABLE X x . EFFECT STEELON DECOMPOSITIOS OF CONCENTRATED PEROXIDE

L1

'% ueroxide ." . 7 days 15 days 22 days 29 days 36 days Weight, grams Initial Final Change a

By difference.

D

E

A 99.39 0.51 0.10

B 99.49 0.43 0.08

C 99.61 0.26 0.13

99.70 0.23 0.07

99.80 0.14 0.06

82:l 78.0 74.3 68.2

84:2 81.2 79.2 75.9

85:5 83.6 82.2 80.0

64:8 82.3 80.5 77.7

8610 84.3 83.4 81.9

3.2699 3.2697 -0.0082

2.6483 2.6484 0001

+O

1.5567 1.5564 -0.0003

2.4244 2.4244 0.0000

2.6267 2.8267 0 0000

INDUSTRIAL AND ENGINEERING CHEMISTRY

March, 1946

TABLE XXII. STABILITYOF PEROXIDE IN THE PRESENCE OF DIFFERENT TYPESOF ALUMINUM AT ROOM TEMPERATURE Aluminum % peroxide 1 day 2 days 4 days 5 days 6 day8 7 days 14 days 21 days 28 days 35 days 42 days

90 90 89 89 88 87 87 84

Q

90 90 90 90 89 88 88

87 86.8" 86.3"

87 87.3' 86. g5

88

81

80.0' 77. 8a 3.1106 3.1097 -0.0009 -12.4

Initial wt., $. Final wh g. Wt. cha&e, g. Change in % peroxide

90 90 89 89 89 88 88

88

2.1936 2.1930 -0.0006 -3.9

2.3591 2.3583 -0.0008 -3.3

317

covered by a 150-ml. beaker. Each test piece was 0.70 X 8.20 x 2.9 cm. One hundred parts per million (21 mg. of anhydrous material) of the stabilizers in Table X X I X were added; each flask was covered, stored at room temperature, and analyzed a t intervals. One hundred parts per million was the concentration chosen to test a lacge number of prospective stabilizers with stainless steel and aluminum. Tables X X I X and X X X show that, in general, acidic materials other than phosphate are to be avoided. The phosphates as a class were the best stabilizers. The best stabilizers shown in Tables X X I X and X X X were selected and tested a;t two concentrations as shown in Table XXXI. The data are in agreement with those in Tables XXVII and XXVIII in that the higher concentration of stabilizer seems to be less effective; the optimum concentration was not determined. The results show t h a t hexamine and magnesium oxide are less effective than the phosphate.

By gravimetric analysis. SHOCK SENSITIVITY

peroxide and air, the stainless steel pieces were immersed in 150 ml. of concentrated peroxide in a 250-ml. flask overnight (16 hours) and then kept in a n empty flask during the day (8 hours). Comparison of the results in Tables XXV and XXVI shows that alternate exposure did not noticeably affect the decomposition rate of the peroxide. U S E OF STABILIZERS

The shock sensitivity of 90% hydrogen peroxide was investigated to determine the danger of detonation during use in the field. Three methods were used t o initiate detonation. HAMMER-DRIVEN PISTON.One drop of liquid was placed on the bottom of a test cup (Figure 2) with a medicine dropper; and the piston was suspended above i t by a weak coil spring. The piston was normally suspended halfway into the cup t o prevent the capillary action which would occur if the piston came into contact with the liquid. A 200-gram hammer was then dropped on the piston from a predetermined height. Between trials the cup was thoroughly washed with distilled water and acetone, and dried. At full scale (350 cm.) pure 90% hydrogen peroxide could not be detonated in this system in either' stainless steel or aluminum cups. T o check the system, R nitroglycerin was tested under the same conditions and detonated consistently with a

Since stainless steel may, under some conditions, cause rapid decomposition of concentrated peroxide, it was thought advisable to determine whether a stabilizer could be found which would diminish decomposition in stainless steel and still not affect stability in aluminum. Tables XXVII and XXVIII show that high concentrations of stabilizer may be worse than no stabilizer at all. After finding- t h a t concentrated peroxide may decompose fairly rapidly in the presence of steel, a w TABLE XXIII. STABILITY OF 89.4% PEROXIDE IN PRESENCE OF DIFFERENT TYPES screening test was run for stabilizers OF ALUMINUM AT 50" C. that might be added to concehtrated None 2s1/4H 99.7% 52S'/rH Aluminum peroxide. Two test pieces of 18-8 Test No. A1 A2 B1 B2 c1 c2 D1 D2 stainless steel, type 304, were suspended % peroxide 1 day 89 89 89 89 89 89 88 on glass rods. The metal was com3 days 89 89 88 89 88 88 88 89 88 4 days. 89 89 88 88 88 88 89 pletely immersed in 150 ml. of concen5 days 88 89 88 87 88 86 88 88 88 trabed peroxide in the 250-ml. flask, 6 days 88 88 85 86 87 87 88 86 11 day@ 8 8 . 5 88.4 18 daysa 87.7 87.6 25 daysa 87.4 87.2 86.7 86.3 32 deyea Changein%peroxide 2 . 7 3.1 Weight, grams Initial Final . Change .. By gravimetric analysis.

.,.. ..

...

82.0 71.1 65.6 39.5 49.9

81.2 73.1 62.4 34.6 54.8

87.7 86.4 86.0 84.8 4.6

2.2072 2.2069 -0.003

2.1871 2.1866' -0.005

87.8 86.1 85.4 83.9 5.5

2.1761 2.1761 0.0000

2.1272 2.1272

+O.OOOZ

87.7 86.2 85.3 83.8 5.6

1.6972 1.6971 -0.0001

87.5 79.7 75.0 68.5 20.9

1.6886 1.6886 0,0000

Q

\-__I

-.

TABLE XXIV. STABILITY OF 89.5y05 PFROXIDE IN PRESENCE OF TIN,TANTALUM, AND

.2935''+QQ0021' OD.

bj9

-

:,I

--n .sooo"faoooz"1.0.

\

I

45A 45 B Run No. Material Silicone Silicone Temp., C. Room 50 % peroxide 2 days 90 90 90 8 days 90 90 4 days 90 5 days 89 88 88 6 days 88 88 7 days 88 14 days 87 87 85 21 days 87 28 days 87 86 35 days= 86.0 83.9 Weight, grams Initial Final Change ... %changeinperoxidea - 8 . 5 -5.6 a By gravimetrio analysia,

...

... ...

... ...

SILICONE

46 A

Ta Room 90 90 90 89 88 88 88

88

88 87.9 0.8312 0.8311

-0.0001

-1.6

40B Ta 50 90 90 90 89 88 87 R? _. 86 86 84.8 0.8701 0.8703 +0.0002 -4.7

47Al None Room

47A2 None

47 B1 Sn

50

Room

90 90 90 88 88 88 88 88 88 87.6

00

90 87 -. 87 87 87 86 86 86.1

90 90 89 88 87 87 87 87 87 87.9

... .. ....

. .. . .. . ..

-1.8

DO

-3.4

9.0503 9.0507 4-0.0004 -1.6

47 B2 Sn 50

80 90 88 88 87 87 s6 b6 86.8 8.6060 8.6062 +0.0002 -3.4

318 TABLE XXT'. Sample NO.

STABILITY OF

90.270 PEROXIDE IN PRESESCE

% Peroxide after Following Days: Steel

2

3

4

5

6

7

12

14

B2

c1 C2

D1 D2 El E2

16

SS 446 SS 446 SS 18:s SS 1 8 : s WD 1010 IT'D 1010

1

2

3

4

6

7

9

88 87 88 88 87 87 88 88 89 87

87 87 87 88 87 87 88 88 88 87

87 87 87 88 87 87 88 88 87 87

87 87 87 87 87 87 87 87 87 87

86 87 87 87 87 87 87 87 87 87

86 87 87 87 87 87 87 87 87 87

86 86 87 87 87 87 87 87 87 86

Peroxide of Control Samples after Following 12 14 16 18 19 20 21 23 24 26 88 88 88 88 88 88 88 88 88 88 86 86 87 89 89 88 88 88 88 88

70

2 F1 F2

90 90

3 89 90

4 89 88

5 6 89 88 88 88

7 88 88

O F STEEL AT R O O M TEMPERATURE

% Peroxide after Following Days (2nd Contact):

A1 A2 B1

a

Vol. 38, No. 3

INDUSTRIAL AND ENGINEERING CHEMISTRY

11 13 15

22

2ga

36a

86 86 86 85 87 87 87 87 87 87 87 87 87 87 87 87 87 87 86 86

Wt.ofFinal, Test Piece Initial, Change, -~ grams grams mg. 2.1564 2.1583

2 9512

3 0826 2 9307 2,8961 5.7482 5.6377 5 6055 5 6050

Days:------------, 28 30 32 88 88 87 88 88 88

2.1555 2.1576 2 9515

3.0322 2.9305 2.8'361 5.7485 .5.6372 5,6057 5.6047

-1.1 -0.7 +0.3 -0.4 -0.2

-0.3 +0.3 -0.5 +0.2 -0 .

x

39 46a 63" 87 8 6 . 9 8 7 . 5 88 8 7 . 5 87.3

By gravimetric analysis. TABLE XxLrI.

EFFECT O F ALTERSATE EXPOKRE OF ALGMIKUMTO k R AXD PEROXIDE

STEEL AtiD

% Peroxide

The system was so coiiatructed that the additional volume of the gas system after rupture of the diaphragm gave a negligible pressure drop. I n this system the liquid could be driven a t high velocity through or against any desired type of fitting. I n general, tests .. .. .. .. were conducted as follows: The bursting diaphragm of 87 88' 87 87 88' 88 87 88 87 87 88 88 desired rating was installed and tested for leaks. The 87 8888 87 88 88 test fitting vias installed, the liquid under test filled into .. .. .. .. .. .. .. , . .. .. .. .. ., .. the blow case, and the system pressurized. Before use .. , . .. .. , . .. .. .. .. .. with 90% hydrogen peroxide the stainless steel blow case and U-tube were pickled overnight with concentrated SG:7 8G:9 87.'2 s ~ . ' s s S : ~ 8i:0 nitric acid. In this system 90% hydrogen peroxide 85.'2 &'l 85:7 82:9 87:s 85:9 did not detonate when driven by 2000 pounds per dates. b 7 days. 13.7 days. d 20.7 days. square inch air pressure against the closed end of a ll/l-inch pipe or when driven through a '/r-inch hole TABLEXXVII. EFFECTOF CONCEhTRATION OF STABILIZER in the end of the pipe. (NaaP04.12H20) ON 89.S% PEROXIDE SOLUTIONS h k m m GUN FIRE. 90% hydrogen peroxide was confined 70Peroxide a t 70Peroxide a t 100' C. in 1-quart rectangular aluminum containers with '/c-inch walls. NaaPOa, 50' C . Test P.P.M. 7 days 14 days 3 days 7 days 14 days The containers were filled to 10% void. Armor piercing, tracer, A 100 89.3 89.1 .. 77.0 60.8 n 500 88.8 87.2 0 .. .. and incendiapy bullets were fired into the containers a t 100 yards C 1,000 S8.0 86.5 0 .. from a 0.50-caliber machine gun. S o n e of the three ammunition D 5,000 08.5 0 .. .. .. E 10,000 Oa .. .. .. .. types had any effect other than to pierce the containers. a At t h e end of 3 days this sample had completely decomposed. The tests all show that 90% hydrogen peroxide is safe frorrl shock detonation if not contaminat'ed wit,h organic impurities. OF 89.8% PEROXIDE WITH TABLE XXVIII. STABILITY Du PONT STABILIZER AT 100" C. Hours in Contact with: Air Peroxide Total 8a 0 0 0 16 16 9 0 32 40 10 8 11 32 32 64 12 40 48 88 13 48 64 112 14 48 88 136 15 56 104 160 16 64 120 184 17 72 136 208 18 80 152 232 19 88 168 256 20 112 168 280 21 136 168 304 328 zza 144 184 23 168 184 352 29a 168b 328C 496d a Gravimetric analyses on these

May

SS304 SS304 88.4 88.4 88 88 88 88 88 88 88 88

SS446 88.4 88 88 88 88

WDlOlO 90.7 A1 2s A1 88.4 88.4 88.4 88 88 88 88 88 88 88 88 88 87 88 88

Stabilizer", % Peroxide 14 da5-s P.P.M. 7 days 85.4 82.3 110 28.6 77.7 B 505 C !,040 86.1 82.7 D 5,100 87.4 63.7 E 10,000 64.5 45.5 a Prepared according t o method of Gilbert and Reichert ( 1 ) . Test A

PRESSURE GAGE

hammer fall of about 20 cm. The addition of small amounts of organic solvents, such as acetone, to 90% 'hydrogen peroxide made it sensitive to shock. When impacted by the piston, one drop of the material detonated n i t h a loud report, usually accompanied by a flash of flame. All tests on 90% hydrogen peroxide in this system indicated that the peroxide was insensitive to shock detonation if no organic impurities were present'. HIGH-PRESSURE GAS IMPACT.An apparatus was designed (Figure 3) to duplicate the shock received by a liquid in a diptube blow case a t the time of the sudden pressure application needed for rapid injection into a reaction chamber. This was accomplished by a pressure reservoir, separated from the liquid under test by a flange containing a rupture diaphragm with known bursting pressure. Pressure could be built up in the reservoir with any desired gas until the bursting pressure of the disk was reached. Rupture of the diaphragm provided instantaneous pressure release on the liquid in the U-tube below t'he diaphragm.

MODIFIED N, CYLINDER

CAPPED FILLING PIPE

STAINLESS STEEL RESEAVOR I16 CU.IN.QS GAL.

I'bRAlN VALVE EXTEND HANDLE THRU BARRICADE

Figure 3.

Gas-Hammer Detonation Tester

All parts to withstand 2000 pounds pressure safely

INDUSTRIAL AND ENGINEERING CHEMISTRY

March, 1946 ~~~

319

~

TABLE XXIX. EFFECTOF 100 P.P.M. STABILIZER IN 9201, PEROXIDE WITH STAINLESS STEEL ---Wt. ---Initial, 36 grams

yo Peroxide after Following Number of Days: Stabilizer NarPz07.10HzO NasPO1.12H90 NaHzPOa.Hz0 &PO4 (85%) NHINOS NaNOs KF-HzO NHiF NHIHF~ Al(0H)a AlzOa MgO Sn0z SnO Hexamine None

.

1 89 90 89 90 90 88 90 90 89 87 ..

88 90 90 90 90 90

1 90 Days: 1 HNOa (70%) 90 Days: Has04 (10%)

r

2 89 90 89 89 85 86 90 89 89 86 88 89 90 89 90 89

4 89 90 89 89 81 79 90 89 89 71

5

6 89 90 89 89 78 73 90 89 87 54 66 89 74 74 88 79

2 88

3 87

4 87

..

86

..

86

3 89

4 89

5 89

6 84

7 82

8 80

10 81

83

5

7

9 87 88 87 87 71 63 87 82 84 42 53

11

87 _.

65 65 86 73

6

7

13 85 88 87 87 55 43 85 77 83 24 34 86 51 48 85 63

15 85 87 87 86 47 38 84 76 79 16 25 86 37 42 85 69

10 86 12 80

12

8

,

18 84 87 87 86 43 29 82 75 78

87 86 86 31 19 78 73 76

29 83 87 86 86 18 2 75 73 72

86 31 31 84 51

86 24 28 84 39

86 21 22 84 38

86 17 10 83 22

13 84 17 72

15 82 19 72

18 79

25 68

32 37

4.8784

4.8733

-1.5

21 69

28 58

35 35

4.9760

4.9750

-1.0

..

..

..

14 77

22

of Test PieceFinal, Change, grams mg. 4.9338 -0.1 -0.4 5.0215 -0.2 4.7595 4.9420 -0.4 -0.1 4.9499 +o. 1 4.9553 -2.7 4.7750 -4.0 4.8789 4.8955 -6.3 ... Last Last ... -0.4 4.9611 -0.4 5.0275 4.9638 -0.3 4.9912 -0.3 * 5.0607 -0.6

20 84 87 86 86 35 24 79 73 77

84

.. ..

....

83. 3a 88.0G 84.9'" 85.0a

...

7i 61 63

.. ..

...

...

86.3"

... ...

80.3a 8

By gravimetric analysis.

TABLE XXX. EFFECTOF 100 P.P.M. STABILIZER IN CONCENTRATED PEROXIDE WITH 99.7% ALUMINUM yo Peroxide5 after: Test

A B

C D E F G H

I

J K L M N 0

9

Stabilizer NuPnO7 NaaPOa NaHaPOI Hap04 (85 %)

&so4 "01

NHaNOa NaNOa

KF

NItF NH4HFi Al(0H)s AlaOa

E%:

SnO Hexamine DuPont None

7 days 88.5 89.2 88.8 88.8 87.2 87.8 88.4 88.4 88.1 83.2 85.6 88.0 87.0 89.0 88.8 88.9 88.1 85.8 89.1

15 days 87.2 88.7 87.5 .87.4

80.8

85.5 86.8 86.5 86.3 70.9 83.6 86.0 85.6 88.0 87.0 87.8 85.9 74.6 88.0

29 days 85.7 87.9 85.8 86.2 45.3 81.2 84.6 84.2 82.2 52.6 81.6 83.1 82.7 86.6 84.3 86.6 81.9 56.8 86.8

41 days 85.0 87.4 84.5 84.8 1.4 76.4 82.6 81.6 78.2 41.4 78.0 79.7 76.2 85.8 82.4 83.3 78.4 47.4 83.9

Wt. of Test Piece Initial, Final. Change, grams grams mg.

TABLE XXXI. EFFECTOF STABILIZER IN 89.3% PEROXIDE STEELAND ALUMINUM AT 50" C. (150 ML.) WITH STAINLESS Test

Stabilizer

P.P.M.

+0.2

$0.1 +0.2 0.0 -5.0 -0.4 +o. 1 -0.2 -2.6 -6.2 -4.3 $0.1 $0. 1 +0.3 1.3668 1.4118 1.3621 1.4416

1.3660 1.4118 1.1964 1.4411

$0.2 -0.8 0.0

-166.7

-0.6

014'nal concentration of peroxide was 89.4% for testa A to 0, and 89.8% P to 5.

gr

Wt. of Tast Piecea, Gram Initial Final Change

NarPzOr NasPO4 NaHnPO4 Hap04

MgO

F1

Hexamine

G1 G2 H1 H2

None None None None

F2

,. . ,.. ... ...

5.4627 5.4178

.... .. ..

5.4625 5.4174

....

K 6-

51.9 59.5 1.2