| Pages:
1
..
18
19
20
21
22
..
28 |
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
You could try some hardware store zeolites as molecular sieves to pull the last bit of water out. Have you checked the boiling pt? It should be
elevated a bit by the water if there.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
Sedit
International Hazard
Posts: 1939
Registered: 23-11-2008
Member Is Offline
Mood: Manic Expressive
|
|
What would the zeolites be marketed as in the hardware store? Just zeolite or is there a brand to look for?
|
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
Zeolite.. they will be with the water purification materials. Also do a google for zeolite..
http://www.bearriverzeolite.com/brz-specifications.htm
[Edited on 3-2-2009 by chemrox]
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
Panache
International Hazard
Posts: 1290
Registered: 18-10-2007
Member Is Offline
Mood: Instead of being my deliverance, she had a resemblance to a Kat named Frankenstein
|
|
dryer cartridges for refrigeration fluids are an easily sourced source of zeolites. Danfoss is a large supplier manufacturing out of mexico i believe.
Almost every suburb in the western world will have a refrigeration mechanics supplier as it is such an essential industry for food safety.
|
|
|
Picric-A
National Hazard
Posts: 796
Registered: 1-5-2008
Location: England
Member Is Offline
Mood: Fuming
|
|
Has anybody got any information of the synthesis of Hydrazine from chlorourea and sodium hydroxide?
I understand chlorourea can be made by passing chlorine through a soloution of urea with a suspention of ZnO (can CaCO3 be used instead of ZnO?)
I guess i could just acidify with H2SO4 to precipitate the sulphate from the reaction mix..
thanks in advance.
|
|
|
Panache
International Hazard
Posts: 1290
Registered: 18-10-2007
Member Is Offline
Mood: Instead of being my deliverance, she had a resemblance to a Kat named Frankenstein
|
|
Does silver(II) form any volatile salt or complex at stp?
Are the ammoniated silver(II) complexes, that are reputed to be explosive, so sensitive and/or easily formed, that one should avoid any contact
between ammonium solutions and silver(II) solutions or are the salts/complexes only explosive when dry?
|
|
|
Jor
National Hazard
Posts: 950
Registered: 21-11-2007
Member Is Offline
Mood: No Mood
|
|
Yes, it forms a pyridine-complex, and it can be isolated as the peroxidisulfate salt:
http://www.versuchschemie.de/topic,11731,-Tetrapyridinsilber(II)-peroxodisulfat.html
If you can't read it:
-dissolve 15g K2S2O8 or 13,2g Na2S2O8 in 400ml water.
-Dissolve 4,5g AgNO3 and 5ml pyridine in 100mL water.
Add the solutions to eachother, a orange color is produced and precitipate is formed. Leave the solution to stand for 30min.
|
|
|
woelen
Super Administrator
Posts: 8012
Registered: 20-8-2005
Location: Netherlands
Member Is Offline
Mood: interested
|
|
Interesting thing about silver(II)-pyridine complex. Nice to try on a reagent tube scale.
@Panache: You are talking about ammoniated silver(II) complexes, but these are plain silver(I) complexes. If you mix ammonia and a solution of a
silver(I) salt and allow to stand for a few hours, then a solid silver(I) compound (some amminie/nitride/amide complicated badly specified complex) is
formed, which is extremely sensitive to mechanical agitation. Simply decanting the wet solid from a container may lead to an explosion already.
|
|
|
stoichiometric_steve
National Hazard
Posts: 827
Registered: 14-12-2005
Member Is Offline
Mood: satyric
|
|
Are Swagelok threads a proprietary thing or is there a standard naming for it? I have a manometer with a 1/8" (or so i think, the small one) outer
threading and i need to adapt it to a tube nipple. I haven't found anything so for that could do this.
|
|
|
Panache
International Hazard
Posts: 1290
Registered: 18-10-2007
Member Is Offline
Mood: Instead of being my deliverance, she had a resemblance to a Kat named Frankenstein
|
|
| Quote: | Originally posted by stoichiometric_steve
Are Swagelok threads a proprietary thing or is there a standard naming for it? I have a manometer with a 1/8" (or so i think, the small one) outer
threading and i need to adapt it to a tube nipple. I haven't found anything so for that could do this. |
I haven't found anything that fits other than Swegelok stuff, however i have not asked the Swagelok rep directly, not that he would know neccessarily
being a sales rep, lol. I try to avoid the system given the joins are not guaranteed once loosened and retightened (as compared to the Prochem system
which is). Swagelok however do offer a full range of thread to nipple adaptors which could be ordered online easily enough.
Alternatively buy 20 old GC's for $20 and salvage the nipples.
|
|
|
hector2000
Hazard to Others
Posts: 127
Registered: 22-8-2006
Member Is Offline
Mood: Cool
|
|
what componet will produce if water add to phenylacetyl chloride?
Chemistry=Chem+ is+ Try
|
|
|
sonogashira
National Hazard
Posts: 555
Registered: 10-9-2006
Member Is Offline
Mood: No Mood
|
|
^ Carboxylic acid will be formed. Phenylacetic acid.
|
|
|
Intergalactic_Captain
Hazard to Others
Posts: 228
Registered: 4-9-2004
Location: somewhere where i don\'t know where i am
Member Is Offline
Mood: frabjous
|
|
http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV1...
Is there any reason why the above reaction is not used more often in the preparation of nitrostyrenes? Granted, it is for unsubstituted benzaldehyde,
but I can't see any reason why it isn't used in any, for example, 2c-h syntheses.
What about the 3,4,5 substitution pattern? It seems like it would be easier to use NaOH as the "catalyst" (though not finding a mechanism, I'd
imagine that it proceeds through sodium methyl-nitronate) than trying to find/prepare some odd amine.
If you see me running, try to keep up.
|
|
|
Nicodem
Super Moderator
Posts: 4230
Registered: 28-12-2004
Member Is Offline
Mood: No Mood
|
|
Maybe you just did not look hard enough. I have seen a few examples at the Hyperlab forum.
…there is a human touch of the cultist “believer” in every theorist that he must struggle against as being
unworthy of the scientist. Some of the greatest men of science have publicly repudiated a theory which earlier they hotly defended. In this lies their
scientific temper, not in the scientific defense of the theory. - Weston La Barre (Ghost Dance, 1972)
Read the The ScienceMadness Guidelines!
|
|
|
Intergalactic_Captain
Hazard to Others
Posts: 228
Registered: 4-9-2004
Location: somewhere where i don\'t know where i am
Member Is Offline
Mood: frabjous
|
|
The Hyperlab? Not speaking russian, I've never checked it out. Would you be able to give any examples of reactions tried and what the yeilds were?
...When I said it was not used often, what I meant was that in my beilstein searches I've not seen it more than a couple of times, and in googling and
searching the old rhodium archives it's never come up (everyone seems to use EDDA).
If you see me running, try to keep up.
|
|
|
Ebao-lu
Unregistered
Posts: N/A
Registered: N/A
Member Is Offline
|
|
| Quote: | | ...When I said it was not used often, what I meant was that in my beilstein searches I've not seen it more than a couple of times, and in googling and
searching the old rhodium archives it's never come up (everyone seems to use EDDA). |
So you are concerning the catalyst? Oh dear, there are many catalysts except EDDA. For example, ammonium acetate, cyclohexylammonium acetate.
Alkalines will also do. Just google smth like " Henry reaction catalysts"
I thought first you did not find at rholdium any examples of henry reaction at all..
|
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
I'm sorry am I reading this correctly? You didn't find examples of the Henry reax at Rhodium archives? No that can't be right. My question is in
the Henry reaction between benzaldhyde and nitroethane have better catalysts been found since the Org Syn article posted by Nicodem? I seem to recall
this being done with ammonium acetate but the mixture was kept in the dark for two weeks until yellow crystals of nitropropene formed.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
Formula409
Hazard to Others
Posts: 129
Registered: 13-12-2008
Member Is Offline
Mood: No Mood
|
|
Is it possible to isolate the Schiff Base of a ketone such as P2P/MVK/MDP2P in order to get 100% imine formation, aiming to increase the yields of an
Al/Hg reduction?
Formula409.
|
|
|
solo
International Hazard
Posts: 3975
Registered: 9-12-2002
Location: Estados Unidos de La Republica Mexicana
Member Is Offline
Mood: ....getting old and drowning in a sea of knowledge
|
|
HOw can ifigure out the size of a reflux column when refluxing in various size flasks and volume in flask,,,,,solo
It's better to die on your feet, than live on your knees....Emiliano Zapata.
|
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
| Quote: | Originally posted by Formula409
Is it possible to isolate the Schiff Base of a ketone such as P2P/MVK/MDP2P in order to get 100% imine formation, aiming to increase the yields of an
Al/Hg reduction?
Formula409. |
I see two questions here. Yes Schiff bases are isolated all the time before the reduction is done. With ketones you need a catalyst like
p-toluenesulfonic acid. A few crystals.
Does that get you 100% yield? Usually not. The reduction doesn't always get you 100% and various methods require different workups that all have
yield implications. You're planning on an aluminum amalgam redux? You will have some washing up to do after that.
[Edited on 15-2-2009 by chemrox]
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|
|
Sedit
International Hazard
Posts: 1939
Registered: 23-11-2008
Member Is Offline
Mood: Manic Expressive
|
|
Is stainless steel resistant to oxalic acid?
Im evaporating a solution of oxalic acid in a stainless steel vessle and the solution is taking on a green color.
Is this from contamination or it the stainless under attack?
Ok I just changed to a glass evaporation plate and on a good note the solution wasnt what was green it just appeared that way because the stainless
steel had turned green.
Have I lost some oxalic due to this or am I still good to go?
I am extracting out of a dilute rust remover solution and I was suprized to find oxalic crystalized nicely on the bottom as soon as I opened it but Im
still awaiting the final yeild from this solution
[Edited on 15-2-2009 by Sedit]
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
|
|
|
DJF90
International Hazard
Posts: 2266
Registered: 15-12-2007
Location: At the bench
Member Is Offline
Mood: No Mood
|
|
I would expect the green colour is from the nickel in the stainless reacting with the oxalic acid. Some yield is therefore likely to be compromised.
http://physchem.ox.ac.uk/msds/NI/nickel_II_oxalate_dihydrate...
|
|
|
Sedit
International Hazard
Posts: 1939
Registered: 23-11-2008
Member Is Offline
Mood: Manic Expressive
|
|
Chances are your right, the color seems to fit and it dont appear that the steel is being heavyly corroded just discolored with a very fine sediment,
after removel of the slight heat there is crystal formation so tommorow Ill be able to tell whats going on.
Always fun to know when you accidently create a cancer causing toxic substance
Knowledge is useless to useless people...
"I see a lot of patterns in our behavior as a nation that parallel a lot of other historical processes. The fall of Rome, the fall of Germany — the
fall of the ruling country, the people who think they can do whatever they want without anybody else's consent. I've seen this story
before."~Maynard James Keenan
|
|
|
Formula409
Hazard to Others
Posts: 129
Registered: 13-12-2008
Member Is Offline
Mood: No Mood
|
|
| Quote: | Originally posted by chemrox
I see two questions here. Yes Schiff bases are isolated all the time before the reduction is done. With ketones you need a catalyst like
p-toluenesulfonic acid. A few crystals.
|
Are they isolated just like amines (ie. extract, acidify, risnse/repeat)?
| Quote: |
You're planning on an aluminum amalgam redux? You will have some washing up to do after that.
|
Actually, I was planning on exploring whether thiourea dioxide (http://www.sciencemadness.org/talk/viewthread.php?tid=11785) is suitable for performing the reduction, naturally I will need some sort of way of
quantitatively measuring yield, so the reduction procedures detailed on Rhodium are unsuitable for research.
Formula409.
[Edited on 16-2-2009 by Formula409]
|
|
|
Ebao-lu
Unregistered
Posts: N/A
Registered: N/A
Member Is Offline
|
|
As i know, the shiff base can be easily extracted by organic solvent. I've seen a procedure, where to P2P(probably, in some org solvent) was added
some 25% ammonia solution, and this mixture was stirred to get a solution of P2P-imine in organic layer, which was further separated and reduced with
NaBH4. Now i don't remember where i've seen it, but it seems to be a basic procedure for imines
|
|
|
| Pages:
1
..
18
19
20
21
22
..
28 |
![[*]](images/xpblue/default_icon.gif){kind=icon}
