-
Aerobic Oxidation
with Bi-Pd/C Cat.
- Slow reaction @50 C pH 9
- www.academicjournals.org_sre_pdf_Pdf2006_Dec_Bian and Shen.pdf
- Experiment with Pd/Al2O3:
chemelab-ucsd-edu.pdf
-
Analytics
- GlucoseToluidineLab.pdf
-
Direct titration with K3Fe(CN)6:
Anal Biochem. 1962 Nov;4:358-77.
Determination of reducing sugars by oxidation
in alkaline ferricyanide solution.
- 10 ml 2% K3Fe(CN)6 in 1M NaOH
= ca. 4.5 - 4.8 ml of 0.5% Glucose
= ca. 6.6 ml of 0.4% Glucose
= ca. 8.8 ml of 0.25% Glucose
= ca. 21 ml of 0,.1% Glucose
-
Catalytic activation of oxygen and hydrogen peroxide
by gold in glucose oxidation
- Chim Ind Milan Italy (2005)
Volume: 87, Issue: 9,
Publisher: Promedia Publishing, Pages: 44-48
- The selective oxidn. of D-glucose to D-gluconic acid with environmentally friendly and cheap oxidants,
such as mol. oxygen and aq. H2O2 in the presence of gold catalysts, is discussed.
By using mol. oxygen, the reaction leads to the formation of gluconate and hydrogen peroxide as a co-product.
The comparison between dioxygen and hydrogen peroxide as oxidants, at different pH and temp., using either supported or
unsupported gold particles, shows that H2O2 allows higher oxidn. rates.
Owing to economic reasons, the use of hydrogen peroxide seems to be limited to the synthesis of free gluconic acid,
whereas oxygen is almost inactive. Moreover, supported gold shows a better performance in relation to durability,
recycling and sepn. properties.
-
Aerobic Oxidation of Glucose with Gold Catalyst:
Hydrogen Peroxide as Intermediate and Reagent
- Advanced Synthesis Catalysis (2006)
Volume: 348, Issue: 3,
Publisher: Wiley-VCH Pages: 313-316
- Careful analytical determinations show that the gold-catalysed
aerobic oxidation of glucose occurs through a two-electrons mechanism
leading to gluconate and hydrogen peroxide. This latter decomposes
before reaching the critical concentration for competing with O2 in glucose oxidation.
A mechanism of glucose oxidation on gold nanoparticles is presented.
-
Oxidation over
supported gold catalysts
-
Applied Catalysis A: General
Volume 388, Issues 1–2, 20
November 2010, Pages 31–36
- Fig. 4. Glucose oxidation conversion curve, catalyst:
0.8 wt% Au/C, cbuffer = 0.1 M, pH 9.5, T = 35 °C,
stirring rate = 1000 rpm, cglucose = 0.1 M, O2 flow = 100 mL/min (1 atm).
- Glucose oxidation over
supported gold catalysts.pdf
-
Journal of Catalysis
Volume 223, Issue 1, 1 April 2004,
Pages 122–133
- a semiempirical model based on a
Langmuir–Hinshelwood-type reaction pathway
is assumed. At 50 °C and pH 9.5 kinetic
parameters were calculated by an optimization routine.
-
Catalysis with colloidal gold
- Applied Catalysis A: General
Volume 297, Issue 1, 4 January 2006,
Pages 1–7
- Platinum on C not suitable !
-
Lab Trials
-
20% Glucose + 0.1 ml MB 0.5%
@ 50 C with air bubbles
with 1.5g Na2CO3 slow down of reaction
with 3 ml NaOH 1M hard to reproduce, similar Na2CO3
- 5.9.12:
add 1ml NaOH every 30 mins
+14% in 1 hr / +20% in 1,5 hrs
- 4.9.212: Blind Test
add 3ml NaOH at start
=> no change after 1,5 hrs
- 31.7.12:
5% Glucose in 3% Na2CO3
=> +60% in 1 hr (? not reproducible)
- 13.9.12:
Try at 60 C
=> brown colour after 1 hr !
- 14.9.12:
20% Glucose + 3ml + 2ml NaOH
+ Au/TiO2 (1%)
+18% in 1 hr / +21% in 1,5 hr
+37% in 2 hrs -> similar MB !
- 18.9.12:
add 6ml 1M NaOH @ start for pH11
every 30 mins add 1ml NaOH
-> +37% in 1 hr / +53% in 1,5 hr
BUT: brown colour after 1,5 hrs !
- 21.9.12:
add 6ml 1M NaOH
and add 1ml NaOH all 30 mins
use Au/C 1% (lmax=524nm) as Cat
- Commercial production with aspergillus niger
http://www.slideshare.net/dengbej/gluconic-acid-2564002
-
Degradation:
- glucose degradation.pdf