greenyppols - 9-9-2005 at 12:24
hi. Im trying to follow a thread on oxidation of toluene to benzaldehyde and I have a couple questions. I notice that in the thread it is later said
that he did not separate out the MAA after precipitation, does this really matter? I also looked up this Uncle Fester fellow that was mentioned in the
thread also. I read info elsewhere in which 'the uncle' suggests filtering the maa through cotton pillow cases??? Wouldnt the acid dissolve
this, or in my chemical ignorance perhaps the acid isnt concentrated enough to cause it to disintegrate, at least not rapidly? I couldnt find how/if
the precipatate was washed with anything or left as is, either. But since its going back into an acid solution after separation it probably doesnt
matter so long as I stay out of contact with it.
Also in the thread it is mentioned the use of a solvent other than toluene for extraction would be better, as toluene left in the cell converts to
benzoic acid. Would DCM be a suitable solvent for this? Or is it only for extraction from the cinnamon oil that was processed later in the same
thread?
I followed the patent mentioned following cycloknights experiment and have not separated out the MAA yet. The precipitate is up to about the 500ml
mark in a 5000ml beaker and I was contemplating the easiest way to get the MAA separated when I thought I'd wait and ask if it was even
necessary. I like my pillow case as it is...but will sacrifice it.
I have yet to acquire lead anodes anyway....and I posted here in miscellaneous as it didnt strike me as appropriate to post it at the end of that long
thread..sorry if it should have gone there. Im sure I'll be corrected if so...
Answered question about other solvent by reading dejavu file from organikum. Ok to use, but no specific mention of DCM so I guess I'll try it
when I get to it.
Answered question about cotton too reading elsewhere.
[Edited on 9-9-2005 by greenyppols]
Foamy!
greenyppols - 14-9-2005 at 11:16
Help? Is there supposed to be foaming in the electric cell I constructed?
I DID see red coming off the anode! However, it was shortly covered by foam that also seemed to generate from both the anode and cathode. Is this
normal or can I somehow stop it foaming?
I'd say there was about 1 cm of foam floating on top.....
Thanks
[Edited on 14-9-2005 by greenyppols]
Polverone - 14-9-2005 at 21:46
Is your sulfuric acid from drain opener? I made maa using that sort of sulfuric acid, and I had foaming at first too. I presume there was some sort of
surfactant in the acid. But the foaming ceased after an hour or so of operation, probably as whatever caused it was oxidized into oblivion.
I suppose you could use cotton cloth for filtration, but I wouldn't expect to be able to use it more than once. And since CycloKnight never
separated the maa in his successful experiments, you probably don't need to either.
greenyppols - 15-9-2005 at 01:02
Polverone, yes it was drain opener recommended in other threads.
Thanks for the info on the foam going away after awhile, I was concerned I messed it up somehow and wasted the material.
I found a ptfe 'brewers funnel' I couldnt find earlier that has a fairly large screen, decanted the mix and put xtra oxidant in some jars
for later use, maybe. It's still pretty 'thick.'
Thanks again..
edit: oh, and I figure alot of the foam was generated because my anodes are the same size...I missed the part where it was mentioned that the -
cathode was much smaller than the + anode..and most of the bubbles were coming from the -.
[Edited on 16-9-2005 by greenyppols]
grinding up the cell mix
greenyppols - 16-9-2005 at 06:18
This made a nice grinder/blender/mixer and seems resistant to H2SO4 so far...its a handheld milkshake maker made by Rival...I tested it by dripping
some drain cleaner acid on the plastic casing before committing it to use...
http://products.consumerguide.com/reviews/product.epub?produ...
It sure made real fast work of all the bits n pieces of oxidant grinding 'em up. The 'bottom suction' it made was strong enough to
attach it to the bottom of the beaker and sucked everything in. I could hear bits in the cell hit the blade and when I didnt hear anything I was
done....20 seconds tops??
Dont know how long it will hold up to the acid..but if anyone has one lying around, it worked fantastic and sure as hell beat the 3 hrs of crushing I
tried with a glass rod before trying it...
just my 2¢ worth..
Fried rectifier...
greenyppols - 25-9-2005 at 14:40
I had a rectifier electrifying a maa cell...i set it at 20amp for while and left...went outside to check a little while ago, and the cell had turned
the deepest darkest purple I'd ever seen..but my rectifier bit the dust apparently...its face is all black and an electrical stink was in the
woods...
This would be my 2nd attempt at oxidizing toluene..first attempt seems to have just smelled toluene..no strong "cherry" smell..but I did
faintly smell something like cherries, I guess, but I havent separated anything. Try n try again..
Polverone - 25-9-2005 at 17:26
I used a small battery charger in my one maa experiment, and I had to run it intermittently. Even with a fan directed on the charger, it got pretty
hot after 15 minutes of operation. So did the cell contents. Have you been following CycloKnight's instructions for your attempted toluene
oxidation? I failed with my small amount of maa, perhaps (I believe) because the acid concentration was too low and the temperature was too low as
well.
Edit: merged with your existing maa topic.
[Edited on 9-26-2005 by Polverone]
greenyppols - 25-9-2005 at 22:19
Yes I am trying to follow cycloknights instructions..I also read the patent and a few other sources about this...
I dont believe the acid mix was too low, but honestly I dont know what concentration it is now.
I didnt extract my apparently failed attempt very well, I think (hey, newbie.), so I know some was left in when I re-generated, and I had to add some
water to get the mix to react, as I didnt see any 'red' coming off and I read that when this happened the acid mix was too high.
Plus I added back in some of the maa precipatate I strained out, figuring that maybe I removed too much as this is what is transformed into the
oxidant, right?
I do have a small 12v 3amp voltage charger, or whatever they are, that is going to be my power source now, as I've written the company I
purchased the rectifier from as it was only 6 months old and used only the last week or so (!) Im too impatient, lol, to wait for 120 amp hours to go
by..I had it set at 10 amps overnight (12 hours) and it was a nice pinkish/tan? color, and I set it at 20 amps for 10 more hours(200 more amp hrs!?),
is when I noticed my rectifier died on me. But when I checked on it at the 5 hr mark it was a nice reddish color and the mix temp was 65º
But boy, what a deep purple there is now. Unless I ruined it, I figure it must have had around 320 amp hrs run through it total. If I did
'ruin' it, it's a good thing I have extra precipitate in jars and this is a learning exercise. 
I didnt realize rectifiers 'blew' so fast, as I thought they were designed for this..electroplating is what it was meant for, so...I
dunno..maybe just defective, I hope. at 20 amps the 4000ml mix was 65ºc..prior to this 10 amps kept the mix 50º, which is what is best temp for the
oxidation of toluene, or so I've read.
bio2 - 26-9-2005 at 01:26
.........didnt realize rectifiers 'blew' so fast, as I thought they were designed for this ..electroplating is what it was meant for,
so...I dunno..maybe just defective....
Maybe so but unlikely as rectifier diodes are very rugged devices. If you will be operating this thing at or near it's maximum current rating
especially along with a low voltage (in it's range) and expect it to last then beef up the fan or add one if needed. Make damn sure the intakes
or vents are not obstructed and if it has bottom vent holes taller feet help.
Needless to say if placed on a pillow against the wall, lol, it will burn up in short order on high.
Check the case temp of the diodes (<100deg C) ,the heat sink compound and mounting screws etc.
greenyppols - 26-9-2005 at 10:48
Its rated at 12v 25amps. I wish I wrote it down, but the last setting was 7v 20amps, at which it fried. (Im pretty sure) and when it was at the lower
setting it was 5v 10amps.
Prior to this, it didnt get warm much, and I had run it at 25amps for a few hours at a time trying to strip chrome plate..and copper plating and
whatever else crossed my path..lol. It didnt come out well, as I was trying to chrome a piece about 29 sq inches and I need at least 1 amp per sq inch
of what Im trying to plate
I probably converted the maa oxidant to god knows what, since adding toluene hasnt oxidized it. Seems like a total wash to me. bah.
I'll try again, with 3 1000ml beakers..I'll try a few and try them 800ml at a time in a cycle..react a little at a time, as my stirring
leaves much to be desired..