Sciencemadness Discussion Board

citric acid and sodium benzoate to benzene?

jimwig - 11-6-2009 at 13:43

recently read about a scare involving (soft drinks) ingrediates (sodium benzoate and citiric acid) reacting to make benzene.......?

has anyone tried this route to benzene yet? cause i sure love drinking pop and if my stomach could stand the abuse then........
(thats a joke, guys and girls)

i have searched and cannot find a ref that talks about this citric acid route.

i have the benzene via alkaline reaction of sodium benzoate (ala the library) method in mind to try. but the yield is small. it seems.

one of the problems is heating. that is to heat the whole banana (listen before you get your lighters out - i know this NOT a real banana - just allegory or some such) sooo i was wondering about using the hydroxides and benzoate in a microwave oven.... heating would not be a problem if something in there is polar.

would have to have a strong non metallic reaction vessel... and then condense via copper tube once the vapor is outside the MO.

what cha think?

entropy51 - 11-6-2009 at 15:34

Jimwig, you may be thinking of asborbic instead of citric acid. I ran across quite a few references to that recently. One is https://www.aibonline.org/researchandtechnical/white%20paper...

It doesn't seem like a good synthetic route to me.

[Edited on 11-6-2009 by entropy51]

jimwig - 11-6-2009 at 16:12

i am quite sure all the posts said "citric acid" but like i say i am getting no hits google on that so maybe the posters were wrong.

soft drinks ingredients have citric acid and sodium benzoate on every one i have read lately.

so i guess my state of confusion goes on.

anyone else.

entropy51 - 11-6-2009 at 17:02

JimWig, you said "i have the benzene via alkaline reaction of sodium benzoate (ala the library) method in mind to try. but the yield is small. it seems."

I usually get over 70% yield of benzene from decarboxylation of sodium benzoate, which I don't consider small for a reaction conducted with lots of heat and no solvent!

not_important - 11-6-2009 at 17:59

Ascorbic acid; it appears urban legend is at work.

https://www.aibonline.org/researchandtechnical/white%20paper...

and

http://www.foodsafety.gov/~dms/benzltr.html

The amounts are in the low to sub-parts per billion range, a bit lower than those from heating dry sodium benzoate to toasty temperatures.



[Edited on 12-6-2009 by not_important]

1- OTC and

jimwig - 12-6-2009 at 11:35

i have read the posts by ordenblitz et al and the return was less than 70Percent.

could you detail a little of your process other than what is written in the member's publications/board?

this excites me because
1- OTC and
2-OT fucking C!!!!!!

thanks

also thanks to notimpotent (sp?) for a direct hit on my question and a thanks you sir!!!!

[Edited on 12-6-2009 by jimwig]

[Edited on 12-6-2009 by jimwig]

anythought concerning the use of a microwave oven in conjuction with the process?



[Edited on 12-6-2009 by jimwig]

entropy51 - 12-6-2009 at 13:13

My benzene prep is more like Magpie's than Ordenblitz', due to the small scale I use.
18 gm benzoic acid and 15 gm NaOH are dissolved in water and evaporated to dryness in a steel basin, then pyrolyzed in a thin layer in a small RB or pear flask attached to a condenser and receiver. I use a Bunsen flame, and turn the flask on its side with the benzoate spread over the wall. The flask doesn't last forever, but I have a large supply of flasks that were extremely cheap, and I don't do this prep every day. Typical yield after drying product over CaCl2 and distilling is about 8.4 gms, or about 73%. About 1 mL of dark orange residue is left in the distilling flask, but the benzene is colorless.

Ordenblitz has me beat for sheer amount of product, but this one may be of use to some. I have a feeling you are thinking of larger scale.

jimwig - 17-6-2009 at 08:03

yes larger scale and starting with sodium benzoate and the hydroxide.

but tell me what you think of using a microwave oven.

are either one of my starters polar? i think not.....?

just test them --- crazy i am !!!

[Edited on 17-6-2009 by jimwig]

sodium hydroxide is polar

jimwig - 19-6-2009 at 09:10

sodium hydroxide is polar and therrefore will heat up in a microwave oven. yeah!!!

that means the reaction of NaOH with sodium benzoate in a ceramic retort heated in a microwave oven should produce benzene. and i am chomping at the bit to do just that.

benzene along with phosphorus and sodium trioxide seem to the top three hard to prepare chemicals. at least for now.. so this might be significant

anyone else interested?

i know i am probably talking to myself here but WTF........

peach - 28-4-2011 at 02:54

I was having a search around on google and found this thread.

I would give a word of caution against heating NaOH / KOH in the microwave. If any of it spills or spatters on the glass turn table, it can get super hot in that spot. This is precisely the method by which the platter in mine exploded upon opening the door, as the cold air entered and the stress in the glass became too much. As the glass is toughened, it holds a lot of energy before bursting. I found finger sized shards of mine on the other side of the room. It went with an extremely loud bang; like a firework right in front of me.

That aside, I have run the benzoate / naoh method just yesterday. It's given 140-150ml of crude, fluorescent orange produce from 400g of benzoate.



Mmmmm.... yuck!



[Edited on 28-4-2011 by peach]

Arthur Dent - 28-4-2011 at 04:33

Hey Peach... good to have you back, I missed your colorful posts my friend! It's been a while... :D

Very cool ghetto boiler setup!

Robert