Table 1.
Screening of reaction conditions for the oxidation of HMF (0.067 m) in chicory root‐derived solution HMF Chic with Au/ZrO2 (entry 1–4) and Pt/C ip (entries 5–8; 5 h, ratio of intended Au/Pt to HMF=1 : 100; entries 1 and 5: 0.1 m pure HMF solution; entry 8: after 5 h addition of another 2 equiv. Na2CO3 and continuation for 17 h).
|
Entry |
Base equiv. |
T [ °C] |
p [bar] |
X(HMF) [%] |
Y(HFCA) [%] |
Y(FDCA) [%] |
C‐balance [%] |
|---|---|---|---|---|---|---|---|
|
1[a] |
8 |
125 |
30 |
>99 |
0 |
>99 |
>99 |
|
2[a] |
8 |
125 |
30 |
>99 |
7.1 |
0 |
7.1 |
|
3[b] |
4 |
125 |
30 |
>99 |
38.8 |
2.3 |
41.1 |
|
4[b] |
2 |
100 |
10 |
76.3 |
27.6 |
0 |
36.2 |
|
5[b] |
4 |
125 |
30 |
>99 |
0.3 |
81.7 |
82.0 |
|
6[b] |
4 |
125 |
30 |
>99 |
11.8 |
13.8 |
25.6 |
|
7[b] |
2 |
100 |
10 |
96.2 |
86.6 |
2.4 |
92.6 |
|
8[b] |
2 |
100 |
30 |
>99 |
17.2 |
58.1 |
75.3 |
[a] NaOH. [b] Na2CO3.