frobet
Harmless
Posts: 3
Registered: 14-12-2012
Member Is Offline
Mood: No Mood
|
|
Potassium to Sodium Borohydride
Attempting to find a procedure for converting Potassium Borohydride into Sodium Borohydride. There seems to be a lot of literature on converting
Sodium Borohydride into a number of different Borohydrides, but nothing about turning Potassium back into Sodium Borohydride.
I'm thinking something with NAOH as Potassium Borohydride is made with Aqueous KOH and NABH4.
Sodium Borohydride Digest
thanks,
Attachment: BoronBrown.pdf (419kB) This file has been downloaded 805 times
|
|
DJF90
International Hazard
Posts: 2266
Registered: 15-12-2007
Location: At the bench
Member Is Offline
Mood: No Mood
|
|
Using NaOH will never work, clearly. If you consider the known preparation of KBH4 from NaBH4, you'll see why:
NaBH4 + KOH => NaOH + KBH4
The only way you'll ever get your idea to work is if you find a solvent other than water that does not react with the reaction species and allows the
reverse reaction.
|
|
garage chemist
chemical wizard
Posts: 1803
Registered: 16-8-2004
Location: Germany
Member Is Offline
Mood: No Mood
|
|
Why can't you use the KBH4 as it is? Are you sure you really need NaBH4?
|
|
frobet
Harmless
Posts: 3
Registered: 14-12-2012
Member Is Offline
Mood: No Mood
|
|
Sodium Borohydride has a significantly higher hydrogen Content than KBH4.
That and I have a large amount of KBH4, I'm frustrated I haven't found anything on converting it to NABH4.
DJF90 I know I couldn't complete that reaction using water as a solvent and I don't really think NAOH is the answer but its a place to start.
The Boron Brown Paper attached gives methods of converting KBH into LIBH using Lithium chloride in THF, would THF serve as a possible useful solvent
for the reaction of NABH4 from KBH?
Attachment: BoronBrown.pdf (419kB) This file has been downloaded 1902 times
|
|
mr.crow
National Hazard
Posts: 884
Registered: 9-9-2009
Location: Canada
Member Is Offline
Mood: 0xFF
|
|
Hydrogen content? You mean per gram? It has the same number of moles of hydrogen, just a higher molecular weight. Unless there is something else going
on.
Double, double toil and trouble; Fire burn, and caldron bubble
|
|
DJF90
International Hazard
Posts: 2266
Registered: 15-12-2007
Location: At the bench
Member Is Offline
Mood: No Mood
|
|
I think you're barking up the wrong tree. Use the KBH4 as is, its a suitable replacement for NaBH4 in almost all cases. Hydrogen density would only
really matter if you're intending on using it for fuel cell purposes.
|
|
frobet
Harmless
Posts: 3
Registered: 14-12-2012
Member Is Offline
Mood: No Mood
|
|
So are we saying it can't be done?
I thought we would at least get some plausible ideas going...
|
|
DJF90
International Hazard
Posts: 2266
Registered: 15-12-2007
Location: At the bench
Member Is Offline
Mood: No Mood
|
|
you havent illustrated why KNH4 doesnt suffice, and what it is you're trying to achieve by this metathesis reaction. Do you specifically need NaBH4?
If you think you do, for what purpose? Other members of the forum might be able confirm or clarify whether it is necessary.
|
|
Nicodem
Super Moderator
Posts: 4230
Registered: 28-12-2004
Member Is Offline
Mood: No Mood
|
|
I seriously doubt that a person who believes the chemical symbol for sodium is "NA" could be competent enough to answer your question regarding a
chemical procedure. If he would have been able to, he would have described the intended use of NaBH4 already in the first post.
|
|
chemrox
International Hazard
Posts: 2961
Registered: 18-1-2007
Location: UTM
Member Is Offline
Mood: LaGrangian
|
|
Added to that, why would you want to convert a more expensive borohydride to the cheaper one. KBH4 is soluble in THF. I have a solution for you. I
will trade you 200 grams of NaBH4 for 200 grams of KBH4. Everyone gets what he wants and no losses due to conversions.
"When you let the dumbasses vote you end up with populism followed by autocracy and getting back is a bitch." Plato (sort of)
|
|