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quino
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http://138.23.152.128/protocols/Preparing%20glyoxal.pdf
http://www.springerlink.com/index/L351W055X3WL48M0.pdf
Preparation of glyoxal by the action of acetylene on gold chloride or gold bromide
Kindler, Karl
Berichte der Deutschen Chemischen Gesellschaft [Abteilung] B: Abhandlungen (1921), 54B, 647-9
The Au is quant. pptd. by C2H2 from aq. solns. of its halides containing not much more than 1.5% Au; the org. products are only glyoxal and
small amts. of CO2; the finely divided Au can again readily be converted into its halides by means of Cl or Br. The C2H2, purified according to
Gottig's directions (Ber. 32, 1877(1899)) and, to free it from any AcH which might have been formed, further washed with 30% NaHSO3 and then with 30%
NaOH, was passed into 2.6 g. of the Au halide in 100 cc. H2O at 70-80° in a flask connected with a condenser, cooled receiver and NaOH wash bottle
protected from atm. CO2 with sodalime. With a moderate stream of C2H2, the reaction is complete in about 2 hrs. The yield of CO2 was about 12%; no AcH
could be detected in the receiver. The filtrate from the pptd. Au with PhNHNH2 in dil. AcOH gave 86% of glyoxal osazone, m. 169-70°.
[Edited on 16-2-2007 by quino]
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quino
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Preparation of stable glyoxal
PATENT NO. FR 1342537
Acetaldehyde (I) (50%) and 40% HNO3, each dild. with deionized H2O in a molar ratio of 2.5:1 were charged continuously with stirring into the
top of one reactor at 38-9° and withdrawn from the bottom of a second reactor at the same temp. A little NO2 was introduced into the first reactor as
an initiator. Reaction time in each reactor was about 3 hrs. A feed of 11 parts I and 6.74 parts HNO3 gave 39.2 parts aq. mixt. contg. 9.1% glyoxal
(II), 6.3% org. acids, 1.4% HNO3, and 16.5% I. This aq. mixt. was concd. at 50° and 50 mm. until HNO3 reached 5% and heated further at 50° for 2 hrs.
after addn. of 0.6 part I to consume remaining HNO3. The mixt. was then passed through an anion exchanger to yield 8.9 parts soln. contg. about 40% II
and less than 0.8% org. acids. This soln. was passed through a cation exchange column (0.6 part acid type resin) and shelf stored at 35-40° for two
months with no discoloration. A similar soln. prepd. with crude HNO3 and non-purified H2O and not treated by cation exchange was yellowish brown in
only two weeks.
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quino
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Preparation of pure glyoxal
Brudz, V. G.; Drapkina, D. A.; Markovich, I. S.
Sb. Statei, Vses. Nauchn.-Issled. Inst. Khim. Reaktivov i Osobo Chistykh Khim. Veshchestv (1961), (No. 24), 98-101
Glyoxal (I) was prepd. by the action of oleum on Cl2CHCHCl2 (II). Optimal 71.5% yields were achieved when II was added dropwise during 1.5 h. to
15% excess H2SO4 contg. 60 .+-. 2% SO3 in the presence of 0.15% HgCl2 and heated 3.5 h. at 58-60°. Glyoxal sulfate (III) was filtered from the cooled
mixt. which contained chlorosulfonic acid. An aq. soln. of III was treated with CaCO3 to free I and ppt. CaSO4.
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quino
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Glyoxal preparation
Toyoda, Yoshiaki;
Patent Information
US 4555583 A
(CHO)2 (I) was prepd. in high yield and with very little formation of HOCH2CHO as the reaction intermediate, by gas phase oxidn. of HOCH2CH2OH
(II) at 450-650° in presence of a Ag (particle size 1 .times. 10-3 mm) catalyst and a P compd. Thus, a reactor contg. Ag and tri-Et phosphite, and
charged with II, steam, air, and N at 502° resulted in 100% conversion of II, a I selectivity of 80.1%, HCHO selectivity of 2.1% and HOCH2CHO of trace
amt.
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quino
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Continuous preparation of glyoxal
Sauer, Wolfgang; Hoffmann, Wolfgang
Patent Information
PATENT NO. DE 2922599 A1 The product gases (450-800°) from glyoxal prepn. (by oxidn. of glycol over Ag)
were quenched (after at most 1 s after leaving the catalyst) with droplets (0-130°) of H2O or aq. glyoxal entering at an angle of 2-85° with the
stream axis. Several examples were given in terms of numbered app. diagrams.
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quino
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Preparation of glyoxal, alkylglyoxals, and their acetals
PATENT NO.
AT 379799 B
The title compds. RCOCHO and RCOCH(OR1)2 (R = H, C1-6 alkyl; R1 = C1-6 alkyl) are prepd. by the ozonolysis of RC(:CH2)CH(OR1)2 at -80° to 0°,
followed by hydrogenation of the ozonolysis product at pH 2-7 while keeping the peroxide content .ltoreq.0.1 mol/L. Thus, H2C:CHCH(OMe)2 in MeOH was
ozonolyzed at -15 to -10° and the product hydrogenated over Pt (prepd. in situ by the redn. of PtO2) at pH 2-4. The stream of H was regulated in such
a way as to keep the peroxide content .ltoreq.0.02 mol/L. The product was purified by ion exchange and rectification, to give 81% OCHCH(OMe)2.
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quino
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Glyoxal preparation
Toyoda, Yoshiaki;
PATENT NO.
US 4555583 A
(CHO)2 (I) was prepd. in high yield and with very little formation of HOCH2CHO as the reaction intermediate, by gas phase oxidn. of HOCH2CH2OH
(II) at 450-650° in presence of a Ag (particle size 1 .times. 10-3 mm) catalyst and a P compd. Thus, a reactor contg. Ag and tri-Et phosphite, and
charged with II, steam, air, and N at 502° resulted in 100% conversion of II, a I selectivity of 80.1%, HCHO selectivity of 2.1% and HOCH2CHO of trace
amt.
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quino
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Title
Continuous preparation of glyoxal
Sauer, Wolfgang;
PATENT NO.
DE 2922599 The product gases (450-800°) from glyoxal prepn. (by oxidn. of glycol over Ag) were quenched (after at most 1 s after
leaving the catalyst) with droplets (0-130°) of H2O or aq. glyoxal entering at an angle of 2-85° with the stream axis. Several examples were given in
terms of numbered app. diagrams.
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quino
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Preparation of glyoxal by nitric acid oxidation of acetaldehyde
Chen, Zhangming;
Fujian Res. Inst. Struct. Matter, Acad. Sin., Fuzhou, Peop. Rep. China
Shiyou Huagong (1987), 16(8), 547-50
Glyoxal (I) was prepd. in 50% yield by HNO3 oxidn. of AcH at 40° and at HNO3/AcH mol ratio of 0.5-1.16. The effects of catalysts, NaNO3, and
AcOH on the yield of I were detd. The reaction mechanism was briefly discussed.
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quino
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Preparation of glyoxal from ethylene glycol at gas phase
Wakimura, Kazuo;
PATENT NO.
JP 03232835 A
Glyoxal is prepd. by gas-phase oxidn. of ethylene glycol with mol. O in the presence of Ag supported on silicon carbide powders as a catalyst
and P (derivs.). A gaseous mixt. contg. ethylene glycol, H2O, air, N, and tri-Et phosphite was passed through a reactor packed with silicon
carbide-supported Ag at 585° to give glyoxal in 99.9% conversion and 84.3% selectivity, vs. 99.9% and 64.8%, without silicon carbide, resp.
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quino
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Preparation of glyoxals
Wakimura, Kazuo;
PATENT NO.
DE 19519426 A1 The title process comprises oxidative dehydrogenation of glycols in the presence of P or a P compd. and a
catalyst comprising Ag and .gtoreq.1 of Au, Pt, Rh, and Pd. Thus, MeCH(OH)CH2OH, (MeO)3P, air, water, and N were passed through a reactor contg. a
catalyst comprising Ag and Au at 491° to give 99.8% conversion with 69.7% selectivity for MeCOCHO.
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franklyn
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| Quote: | Originally posted by The_Davster
For Acquisition, contact your favorite photography supplier and ask them to get it for you, it is slowly replacing formaldehyde as it is less toxic,
some suppliers already have it in stock. |
Not much use to me but for those who care I discovered this source _
http://www.photoformulary.com/DesktopModules/StoreProductDetails.as...
But even for me, two hundred twenty thousand dollars a pint seems a bit steep . 
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Sauron
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Mood: metastable
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There was another item on that page Chemicals - G that ought to interest the members who read PIHKAL all the time.
Gallic Acid 100 g $80
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franklyn
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Glyoxal from Ozonolysis of Benzene
What I don't get is that this is exactly how the Ozonide is made
http://www.sciencemadness.org/talk/viewthread.php?tid=1172#pid13381...
DMSO solvation then determines the product. Cool if it works.
- If anyone can obtain this article please post it in References -
http://pubs.acs.org/doi/abs/10.1021/i360029a017
Glyoxal from Ozonolysis of Benzene
William P. Keaveney, Raymond V. Rush, James J. Pappas
Industrial & Engineering Chemistry Product Research & Development
1969, 8 (1), pp 89–92
It would seem too that Ethandial is becoming an industrial staple.
http://www.entrepreneur.com/tradejournals/article/198473070.html
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