chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
Strange Occurance with H2O2
This is my first post so I will give a very brief introduction. I recently, within the last year, have discovered I have a huge interest in chemistry.
I attended school for computer science and microelectronics but have no background in chemistry, I am teaching myself.
Now for the strange occurrence with Hydrogen Peroxide:
I usually buy lab grade 35% H2O2 from a local supplier, but, this time they were waiting on a shipment. I only needed a very small amount so I decided
to concentrate store bought 3%. Everything was going smoothly I poured in 200ml of 3% into a 600ml beaker. I kept the temperature near 92C until I was
down to what appeared to be under 50ml. I wanted about 40ml so I grabbed an empty 100ml beaker to transfer the H2O2 over to for a closer graduation
mark. When I poured into the smaller beaker it immediately turned bright transparent yellow. Me being stunned I poured it back in to the 600ml beaker
and to my surprise the H2O2 was perfectly clear. I looked at the smaller beaker and the glass had been what changed color. Nothing at all would remove
the yellow tint until I warmed up a 30% NaOH solution inside. It returned fully transparent after about 20min.
My question is, what caused the glass to go yellow? I know glassware tends to fade yellow over years, this beaker was only about a month old. It was
cleaned before usage the same way the larger beaker was cleaned. When I poured it over, the temperature of H2O2 was 85C. I checked my notes to see
what was in the beaker last and it was used for mixing a small amount of 70% HNO3 and 98% H2SO4 for the nitration of cellulose. I take very thorough
notes so if more info is needed I probably have it.
I searched this forum along with a few others and of course Google but I did not see any similar occurrences. If this is a common thing I would like
more information about it. Like I said before I have zero formal training in chemistry, I am doing the best I can by only reading and performing
experiments on my own. If I had the time I would re-enroll into college, focusing on chemistry.
|
|
|
woelen
Super Administrator
Posts: 7987
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
Your observation indeed is very peculiar. The only thing I can imagine is that there was some impurity in the H2O2 which caused the yellow color. A
well-known impurity is phosphoric acid or some phosphate salts, used as stabilizer for the H2O2. Maybe this reacted with some impurity, sticking on
the glass of the beaker? it could also have been some organic compound.
Did you ever have titanium compounds in the glass beaker? These can adhere to glass strongly (as invisible hydrous TiO2) and form intensely
orange-colored peroxo complexes which are quite stable, even at elevated temperature.
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Or chromium compounds? They also form peroxo complexes, intensely coloured...
|
|
|
chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
I have not had any titanium or chromium compounds in that beaker.
I am thinking it had to be some contaminant along the walls of the smaller beaker since it didn't color the larger beaker I started in, nor did the
color of the peroxide itself change. Numerous lab grade organic solvents have been through the small beaker, that could be where some unknowns came
from.
|
|
|
IrC
International Hazard
Posts: 2710
Registered: 7-3-2005
Location: Eureka
Member Is Offline
Mood: Discovering
|
|
Has anyone considered it could be low quality glassware made in China and the impurity is in the glass composition itself?
I would not heat any dangerous liquid in it. Recently I read a story by a member who lost their hands. He said after looking at the broken beaker it
said 'pyrox' not 'Pyrex'. The member was Yamato71 in thread "Life after detonation" link is below.
http://www.sciencemadness.org/talk/viewthread.php?tid=22554#...
[Edited on 4-3-2013 by IrC]
"Science is the belief in the ignorance of the experts" Richard Feynman
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Quote: Originally posted by IrC  | Has anyone considered it could be low quality glassware made in China and the impurity is in the glass composition itself?
[Edited on 4-3-2013 by IrC] |
There's an enormous amount of silly (not to mention borderline racist) kvetch being bandied around with regards to Indian and Chinese
labglass quality. Not surprisingly this emanates from you-know-where. I've sold tons of both Indian and Chinese and would easily vouch for it quality.
Bad apples can never be excluded but that's the same for 'Western' glass.
|
|
|
IrC
International Hazard
Posts: 2710
Registered: 7-3-2005
Location: Eureka
Member Is Offline
Mood: Discovering
|
|
| Quote: Originally posted by blogfast25 | | Quote: Originally posted by IrC | Has anyone considered it could be low quality glassware made in China and the impurity is in the glass composition itself?
[Edited on 4-3-2013 by IrC] |
There's an enormous amount of silly (not to mention borderline racist) kvetch being bandied around with regards to Indian and Chinese
labglass quality. Not surprisingly this emanates from you-know-where. I've sold tons of both Indian and Chinese and would easily vouch for it quality.
Bad apples can never be excluded but that's the same for 'Western' glass. |
Tell that to the injured member. Had He known it was not genuine Pyrex He would not have been nearly killed and as it is badly maimed. I cannot over
stress how tired I am of liberal pukes calling the racist card when the truth does not fit their agenda. The story is true. The facts about defects in
manufacture are equally true. Telling His story was to warn people of dangers which could cause disaster for them in the hopes it may be avoided in
the future by someone else. So is this why you spent the big bucks for college? To come out calling anyone a racist who says anything about what is a
well known fact just because it involves the area and the race whatever it may be, where the defective products are made?
Fuck you and your racist race-card crap I for one am sick of it.
This is His story. At the bottom highlighted in red was the cause of this accident.
Life after detonation - Yamato71
"First, the introductions.
I am a 59 year old Engineer and organic chemist. I hold a federal explosives permit and am licensed to possess, handle, synthesize and use high
explosives. I only mention that so as to stress the point that if what happened to me could happen to me,then it could happen to anybody.
In the early morning hours of November 3rd, 2010, I attempted to synthesize erythritol tetranitrate (ETN), using a procedure I had come across here
and other explosives websites. I had performed this synthesis dozens of times before without incident, until that Wednesday morning. I was preparing
for a WWII reenactment that was scheduled for the next weekend at the local Army post, a gig that I had done 3 or 4 times a year for the past 3 years.
The ETN was needed for the electric squibs that I used to detonate half-pound buried Tannerite charges that were used to simulate artillery impacts. I
began using electric blasting caps, which proved expensive and impractical since I had no legal way to store the caps where I needed to use them.
Instead, I invented a tiny electric match that was dipped in several layers of chemicals, including ETN. When hit with a current, the squib made a
small pop, no louder than a firecracker, but was energetic enough to fire the Tannerite.
Anyway, back to Wednesday morning, I chose to nitrate the erythritol using sulfuric acid and ammonium nitrate since I was out of white fuming nitric
acid. This necessitated a recrystallization from hot methanol, which I proceeded to do in a large beaker on a radiant cooktop. I grabbed a 1L beaker
and brought about 500 ml of MEOH to a low boil while dissolving 50 grams of crude brown ETN into the hot alcohol.
As I turned around to put up the container of dirty ETN, I heard a sound that made the hair on the back of my neck stand up. It was a loud TICK!, the
sound of cracking glass, followed less than a second later by an even louder one. The beaker was cracking from the heat of the hotplate, and the
second crack had opened a crack on the bottom of the beaker. As I watched, the MEOH/ETN solution flowed onto the hot surface. Before I could react,
the leading edge of the pool of solution flashed to dryness and the precipitated ETN deflagrated, igniting the MEOH/ETN in the beaker. I now had a
roaring fire in the stovetop and no good options open to me. For about 3 seconds, I did the singularly most stupid thing I have ever done in my 6
decades on this planet. I leaned in close and tried to BLOW OUT THE FIRE! The sharp crack of another glass fracture brought me out of suicide mode. It
also made me pull my head back, which saved my life. What I should have done right then was drop to the floor and cover my ears. I'd give my left nut
to be able to time travel back 2 years and do that. What I actually did was try to shove the burning beaker into the sink and drown the fire with
water. As I reached for the beaker with both hands, my life was changed forever.
I barely remember the moment of detonation, aside from the curious sensation of electricity coursing through my hands. The actual explosion didn't
seem as loud as it should have been, but having both eardrums blown out will do that. I remember standing there for a few seconds taking mental stock
of my situation, not really sure of what had just happened. As what was left of my hearing began to come back, I began to hear a strange sound that
reminded me of the sound that water from a hose makes when the stream hits dry concrete, sort of a splopping sound. I raised my left arm and
discovered the source of the strange sound. Arching up from the stump of my left wrist was a half-inch wide torrent of bright red arterial blood that
was splashing on the floor and had already pooled for a yard around my feet.
Instinctively, I tried to clamp off the blood flow with my right hand, but the mass of loose bones and tattered pink and yellow tissue that was
attached to my right wrist was no longer a functioning hand. It had just begun to sink in that I had just blown off both of my hands when I heard my
wife screaming from the bedroom. Above all else, I couldn't let her see my hands. I made a run for a downstairs bathroom and blocked the door closed
with my body. By this time I was beginning to feel the effects of blood loss. It was also at this time that my nervous system began to regain
function. That's when the pain started. Now we were both screaming. I managed to tell her to call 911 and that my blood type was A+. I had to staunch
the bleeding, or I wouldn't live long enough for the EMT's to arrive. With no hands, that would be tough. I managed to pull several towels down from a
shelf, cross my arms in front of my chest and lay face-down on the pile of towels. It must have worked because I made it to the hospital. I never lost
consciousness and remember most of the ambulance ride. The last thing I remember was the EMT briefing the surgeon "traumatic bilateral amputation of
the hands". I awoke sometime a day or two later to the sight of the bandaged stump where my left hand had been. I then looked to my right, expecting
to see the same thing. What I saw instead was a miracle. Instead if a slim tapered bandage, my right arm terminated into a huge bulbous blood-soaked
bandage. Somehow, the surgeon managed to find most of the pieces of my right hand and put them back together into something resembling a hand.
Fifteen surgeries later, I'm still getting my life back together. I wear a prosthetic left hand, actually a steel hook. I lost the tips of two fingers
on my right hand. I sustained a degloving injury to my right thumb, nothing but bone and tendon was left. I was given two options, amputation or
lengthy painful reconstruction. I chose the latter. In order to regrow tissue on my thumb, it was implanted into my abdomen for 2 months. After that
delightful time in my life, I endured a dozen more surgeries to carve that mass into a useful thumb.
My life will never be the same. Please think of my accident while you make the energetic materials listed here. I'm not going to tell you not to
experiment with them, I'm just asking you to be careful when doing so. I don't want anybody's wife to be handed their husband's wedding ring after a
fireman found it embedded in the ceiling. How does one wrap their head around something like that?
BTW, the cause of the accident turned out to be the Chinese knockoff beaker that I bought at a kitchen store earlier that
year. The "Pyrex" logo on another one bought at the same time, on closer inspection, read "Pyrox", with a tiny "made in China" text at the bottom.
Instead of being made with Pyrex borosilicate glass, it was cheap soda-lime glass that couldn't stand up to heating. I never noticed the
difference.Please be careful. Yamato71"
[Edited on 4-3-2013 by IrC]
"Science is the belief in the ignorance of the experts" Richard Feynman
|
|
|
chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
| Quote: Originally posted by IrC | | Has anyone considered it could be low quality glassware made in China and the impurity is in the glass composition itself? |
I have heard all the horror stories with "Pyrex like" glassware and I can assure you the beakers used here were not of that type. I have become
friends with a retired chemist who now works at a chemical supply warehouse. When he found out I was an amateur experimenter he allowed me access to
the full catalog at this warehouse. Very good prices on top brand equipment, glass, and ACS/Lab grade chemicals. I even get free samples of glass and
chems.
|
|
|
IrC
International Hazard
Posts: 2710
Registered: 7-3-2005
Location: Eureka
Member Is Offline
Mood: Discovering
|
|
If so then the only other reason I can think of for the color change would be a cleaning chemical that was not completely washed out, left to dry on
the inside walls. At first I wondered if it was not some kind of optical effect due to a glass composition and index of refraction unlike the first
container because you stated it was clear after you poured it back. Definitely an odd occurrence you are talking about whatever the cause.
Sorry about the strong words in my last post being interjected in your thread but no one calls this Cherokee Indian a racist and gets away without
repercussions.
"Science is the belief in the ignorance of the experts" Richard Feynman
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
| Quote: Originally posted by IrC | Sorry about the strong words in my last post being interjected in your thread but no one calls this Cherokee Indian a racist and gets away without
repercussions.
|
I didn't call you a racist. Being a Cherokee though doesn't mean one couldn't be racist though.
Reasoning along the lines of 'maybe it's Chinese?' is nonethless lazy and parallel to racism. What would be proven if we knew that the glass was made
in China? Nothing. Even if we (actually) knew the physicochemical basis of the discolouration AND that it was made in China it wouldn't prove that
glass 'made in China' suffers from this effect, only that this particular piece does.
|
|
|
mayko
International Hazard
Posts: 1218
Registered: 17-1-2013
Location: Carrboro, NC
Member Is Offline
Mood: anomalous (Euclid class)
|
|
| Quote: Originally posted by IrC |
Tell that to the injured member. Had He known it was not genuine Pyrex He would not have been nearly killed and as it is badly maimed.
(much anger snipped)
[Edited on 4-3-2013 by IrC] |
To begin with, n=1 is not a great sample size for this sort of comparison.
I have read that thread with great interest, and think about it whenever I am about to 'play with fire', just to remind myself of the consequences my
actions could have. The same way I think about how terrible a broken femur would be, each time I start a bike ride.
I have noticed that a lot of catastrophes are characterized by a complex chain of events, both human and technical, and the detonation was no
exception. A long chain of poor decision making (working when exhausted, improper heating, poor quality glass, fighting rather than fleeing...) The
injured member indeed seems to agree:
| Quote: |
Just as is the case for any disaster, it was a series of mistakes, poor decision making and just blind dumb luck that bit me in the ass. Removal of
any one of these factors would probably have averted this accident.
|
I don't think it's fair to judge an entire region's production by the end result of a complex causal chain which involved a single instance.
(Full disclosure: I know very little about glassware quality by region.)
As to the original question, I have no idea, but that is very interesting. Have you tried recreating the phenomenon?
|
|
|
chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
| Quote: Originally posted by IrC |
As to the original question, I have no idea, but that is very interesting. Have you tried recreating the phenomenon?
|
I tried several times to recreate the event. After I poured the H2O2 back into the starting beaker I grabbed a couple other beakers straight from the
drying rack, cleaned the same way with dilute HCl then rinsed with warm distilled water, with no luck. Given the possibility that the contaminant was
exhausted, I have yet to concentrate another H2O2 sample from the same bottle and try again. I have plans to do so though.
|
|
|
IrC
International Hazard
Posts: 2710
Registered: 7-3-2005
Location: Eureka
Member Is Offline
Mood: Discovering
|
|
"To begin with, n=1 is not a great sample size for this sort of comparison."
n equals however many there are in existence which are: "Instead of being made with Pyrex borosilicate glass, it was cheap soda-lime glass that
couldn't stand up to heating". Made in China was not a guess coming from some preconceived 'racist' notion as stated by blogfast25. IT WAS WRITTEN ON
THE GLASS! Right there in print 'Made in China'. With the label 'Pyrox' this was quite clearly an attempt to fool non careful observers that this
glass was 'Pyrex', safe to heat in the way Yamato71 did. The glass was made where it was with the clear intent to inform the end user the glass was
Pyrex, not the cheap soda-lime glass it was. This cannot be denied by anyone using reason and common sense to guide their thinking. They would not
have cleverly altered one letter from e to o if subterfuge to lessen costs was not the goal. The main point is if the theory of an impurity was
correct there would be an entire production run made this way, not just n=1.
"borderline racist kvetch"? Do not state you were not implying the word you wrote in your post, this is being
dishonest.
"Not surprisingly this emanates from you-know-where"
No I don't know where kindly inform us. This could be perceived easily as being racism coming from you.
"Reasoning along the lines of 'maybe it's Chinese?' is nonethless lazy and parallel to racism."
Again you call the race card while denying it in your latest post. Again dishonest. I had very good reason to bring it up. I deal with many materials
made in China and impurities are prevalent across an enormous range of materials. For instance copper wire so contaminated with oxygen and other
metals the wire strands rapidly turn jet black and become impossible to solder. Tubes of epoxy and superglue which harden in their unopened tubes
which were manufactured not that long ago. Elements in microphones manufactured in China with rare earth magnets turning to white powder locking up
the diaphram which are less than 2 years old.
I can name dozens of materials with similar problems I have dealt with in the last few years, so that and the memory of recently reading the thread by
Yamato71 gave me the thought that possibly something in the glass composition itself could be the cause of the color change. You came in with the
'race card' hijack of the thread. I have no intention of wasting further time with this stupidity of an argument that can only serve to wreck the
thread started by chemcam. Why would you as a long term member with thousands of posts do this to a brand new member giving him a bad impression of
this site? Worse still then denying it. Race was not the thought on my mind when I made that post it was an honest thought about honest experiences
with products made in China which possibly could have played a part in the color change. In other words an honest legitimate theory, a possibility
which had every reason to be considered since as was stated the glassware was perfectly clean.
"Science is the belief in the ignorance of the experts" Richard Feynman
|
|
|
chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
I too agree that Chinese made products have less developed quality control (low cost = low quality) and it is a valid point to bring up glass
composition, I doubt that is the cause but still worth looking in to.
Had I not done my research thoroughly when building my lab and before synthesizing dangerous and/or energetic materials I may very well have had a
disastrous event like the above mentioned member. I strive to have the best available reagents and glassware even if it means postponing an experiment
to save money for higher grade materials. It can be assumed by that last sentence that I will be waiting for lab grade H2O2.
I am not saying Chinese glass is all bad I just mean it is manufactured to a lower standard than Pyrex.
[Edited on 4-4-2013 by chemcam]
|
|
|
woelen
Super Administrator
Posts: 7987
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
First I want to warn against overheated emotions in this thread. Both IrC and blogfast25 have a point. I agree that chinese material sometimes is of
low quality, but it can also be very good stuff.
Some examples:
- I purchased MoO3 which was stated to originate from China. When I received the material to my surprise it was brown instead of white or very pale
grey. When it was dissolved in a solution of NaOH, a lot of brown flocculent solid was formed and I needed double vacuum filtering through the same
filter to obtain a colorless solution. At least 10% of this material must have been some insoluble impurity.
- I purchased high voltage capacitors (1 nF, 6000 V) from a Chinese eBay seller with the intent to use them in a high voltage cascade circuit. When
the voltage across these capacitors reached 4000 V or so, some of them made a peculiar tickling noise and became conductive between their terminals.
Exit capacitors 
- From the same seller I ordered 20 kV diodes. When the reverse voltage reached somewhere between 12 kV and 15 kV I had a loud BANG and the diodes
simply cracked (breakdown and subsequent destruction due to strong heating).
- I obtained an FM transmitter HLLY TX-01s or something like that, rated at 1 Watt maximum for use in and around the house. This device works great, I
have never had such crystal clear sound and clean signal (low harmonics) from a consumer market FM-transmitter for such a price. So, things can be
good also.
With chinese things you can have good luck, but also bad luck and that is one of the things which I do not like. With electronics and chemicals I
sometimes take the risk, but with glassware I would be more careful. An accident with breaking glassware can have really nasty consequences.
If I buy new glassware for distillation, then I ALWAYS test it with distilling water from a saturated salt solution, which brings the temperature up
to 120 C or so. If the glass withstands distillation of that to the point where many salt crystals remain in the boiling flask, then I trust it. Only
then it is used for distilling other stuff, like Br2, HNO3 or organic solvents.
[Edited on 4-4-13 by woelen]
|
|
|
blogfast25
International Hazard
Posts: 10562
Registered: 3-2-2008
Location: Neverland
Member Is Offline
Mood: No Mood
|
|
Irc, as always you act like a certified nut. There is no talking to people like you, as you can't even see the contradictions in your own flawed
'reasoning'.
There is no case against 'Chinese glassware'. There may be a case against some pieces of glassware or some Chinese makers of glass,
as there are cases to be made against things from other manufacturers, some of which may even be Cherokee! The crass generalisations you come up with
are indeed borne out of simple prejudice, like all racism does. You then proceed to deny it but put you big foot in your mouth.
"Made in China was not a guess coming from some preconceived 'racist' notion as stated by blogfast25. IT WAS WRITTEN ON THE GLASS!"
Replace 'in China' by 'a Cherokee': would your conclusions still hold up? Reminder: you're the one who brought up 'Chinese', indiscriminately.
And 'Mayko' is of course 100 % correct. Well done!
[Edited on 4-4-2013 by blogfast25]
|
|
|
chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
attempting to get everyone back on topic...
What compound(s) could be oxidized to a bright transparent yellow color by hydrogen peroxide? Oxidized compound was stuck on walls of beaker, nothing
could remove it other than a warm NaOH solution.
*Transition metals chromium and titanium have already been discussed.
**The bright yellow color is similar to urine after vitamins have been ingested.
|
|
|
Eddygp
National Hazard
Posts: 858
Registered: 31-3-2012
Location: University of York, UK
Member Is Offline
Mood: Organometallic
|
|
If you have been doing organic chemistry experiments, then there are way too many possibilities to think about. H2O2 can make thioethers turn to a
sulfoxide, but I can't recall any simple, yellowish compound with a sulfoxide. If you have also done there a Fischer-Speier estherification (or used
any sort of acid with the beaker), the traces of the acid catalysts or reagents might help the H2O2 to create hydroxyl radicals, but again, I don't
know how it might create a yellow colour...
I know that this post is just thinking out loud, but maybe some of you know about different yellow compounds with sulfoxides or oxychlorides which may
be the solution.
there may be bugs in gfind
[ˌɛdidʒiˈpiː] IPA pronunciation for my Username |
|
|
chemcam
Hazard to Others
Posts: 423
Registered: 18-2-2013
Location: Atlantis
Member Is Offline
Mood: I will be gone until mid-september, on a work contract.
|
|
Yes, quite a few acids have been through this beaker. For example I have used it in the past to prepare mixed acids for nitrating cellulose so Nitric
and Sulfuric acids have been present. My cleaning solution is dilute Hydrochloric acid but I always rinse with warm distilled water before every use.
I do agree though that small amounts of acid could have been present to catalyze something.
The reason I am asking for specific compounds is so I can recreate the event without going through an unnecessary amount of reagents. I know there
will be many trial-and-error type scenarios to find the most probable contaminant I just don't want to waste more than needed.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
