deadrush
Harmless
Posts: 21
Registered: 3-3-2014
Location: Worcester MA
Member Is Offline
Mood: Fungible
|
|
Glyoxylic acid synthesis - starting w/ oxalic :: w/o PbO2
So i'd like to reduce oxalic acid to glyoxylic acid electrochemically but i have yet to aquire or successfully make PbO2 electrodes. Is there an
alternative that would work?
|
|
|
Texium
|
Thread Moved
30-12-2023 at 06:54 |
Maurice VD 37
Hazard to Self
Posts: 66
Registered: 31-12-2018
Member Is Offline
|
|
Why do you want an alternative ? The usual way for making PbO2 is to take a lead electrode, and use it as anode in an electrolysis with another
electrode as cathode, in a bath of sulfuric acid solution.
[Edited on 30-12-2023 by Maurice VD 37]
|
|
|
mysteriusbhoice
Hazard to Others
Posts: 477
Registered: 27-1-2016
Member Is Offline
Mood: Became chemistry catboy Vtuber Nyaa
|
|
graphite works because this is a reduction reaction so using PbO2 which will oxidize the fk out of the molecule is generally not a necessity. Ir-Ta
MMO also works and Pt also works. The cathode I assume cannot be PbO2 because it would reduce to Pb which btw is a very good reducing cathode.
|
|
|
clearly_not_atara
International Hazard
Posts: 2781
Registered: 3-11-2013
Member Is Offline
Mood: Big
|
|
Maybe you could provide a source for this supposed reduction that you're planning to do so we could have the foggiest clue what you're talking about?
You wouldn't normally care very much about the anode for a reduction, but lead is a preferred cathode for the reduction of oxalic acid to glyoxylic
acid.
https://www.academia.edu/download/81769708/978-1-4419-6996-5...
|
|
|
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
|
|
Reference Information
Glyoxylic acid: synthesis, isolation, and crystallization
M. A. Pozdniakov, I. V. Zhuk
Russian Chemical Bulletin, International Edition
Vol. 68, No. 3, pp. 472—479, March, 2019
Note
The review summarizes approaches, known from the literature, to the synthesis, isolation, and crystallization of glyoxylic acid (GA), which is an
important component in fine organic synthesis and is widely used in pharmaceutical, food, and perfume industry. The review describes the research
dealing with GA synthesis from aqueous solutions of glyoxal by catalytic, electro- chemical, and enzymatic methods and by ozonolysis of maleic acid in
solution. Alternative methods for GA synthesis are considered, for example, from glycolic acid in the presence of glycolate oxidase, oxalic acid,
ethyl alcohol, and from various halogenated acetic acid deriva- tives. Approaches to GA isolation from the products of synthesis depending on the
starting compound are considered, including extraction with amines or alcohols, the use of cation or anion exchange resins at elevated temperatures,
and precipitation as insoluble alkaline earth metal salts. Methods for GA crystallization using various experimental techniques are presented.
Key words: glyoxylic acid, glyoxal, maleic acid, glycolic acid, oxalic acid, heterogeneous catalysis, homogeneous catalysis, ozonolysis.
Attachment: phpPJM0TG (529kB)
This file has been downloaded 154 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
|
|
|
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
|
|
Reference Information on glyoxylic acid electrochemically
Tafel, Julius; Friedrichs, Gustav (1904). "Elektrolytische Reduction von Carbonsäuren und Carbonsäureestern in schwefelsaurer Lösung". Berichte der
Deutschen Chemischen Gesellschaft. 37 (3): 3187–3191. doi:10.1002/cber.190403703116.
Cohen, Julius (1920). Practical Organic Chemistry 2nd Ed (PDF). London: Macmillan and Co. Limited. pp. 102–104.
Attachment: phpKn4yjY (263kB)
This file has been downloaded 143 times
Attachment: practical_organic_chemistry-1.pdf (4.4MB)
This file has been downloaded 122 times
It's better to die on your feet, than live on your knees....Emiliano Zapata.
|
|
|
![[*]](images/xpblue/default_icon.gif){kind=icon}
