Table 2 Dehydrogenation of HCOOK: Variation of catalysts and solvent

From: Development of a practical formate/bicarbonate energy system

View full size image

Entry

Cat.

Solvent/H2O[x/y mL]

Gas volume [mL]

H2/CO2 [%]

H2 yield [%]

TON H2

Rate H2release [mL h−1]max

1

Ru-1

DMF/H2O (20/5)

285

99/1

6

1150

30

2

Ru-2

DMF/H2O (20/5)

390

99/1

14

1580

80

3

Ru-3

DMF/H2O (20/5)

18

99/1

<1

70

4

4

Ru-4

DMF/H2O (20/5)

540

99/1

19

2180

90

5

Ru-5

DMF/H2O (20/5)

1765

99.6/0.4

63

7110

330

6

Ru-6

DMF/H2O (20/5)

1420

99.5/0.5

51

5770

500

7

Ru-7

DMF/H2O (20/5)

1415

99.6/0.4

51

5760

420

8

Ru-8

DMF/H2O (20/5)

87

99.5/0.5

3

350

18

9

Ir-1

DMF/H2O (20/5)

1915

99.5/0.5

69

7790

3600

10

Ir-2

DMF/H2O (20/5)

0

–

–

–

–

11

Ir-3

DMF/H2O (20/5)

0

–

–

–

–

12[a]

Ru-5

DMF/H2O (20/5)

1100

85/15

34

3820

165

13[b]

Ru-5

DMF/H2O (20/5)

2765

99.7/0.3

99

11,260

400

14[b,c]

Ru-5

DMF/H2O (20/5)

4275

99.6/0.4

62

17,390

600

15[d]

Ru-5

DMF/H2O (20/5)

2920

98/2

99

11,630

4650

16[c,d]

Ru-5

DMF/H2O (20/5)

7005

96/4

99

27,470

4800

17[c,d,e]

Ru-5

DMF/H2O (20/5)

6575

98/2

94

263,200

2700

18

Ru-5

DMF/H2O (15/10)

6700

98/2

98

26,820

5100

19

Ru-5

Triglyme/H2O (15/10)

764

94/6

32

3181

360

20[c, d]

Ru-5

Triglyme/H2O (15/10)

2210

92/8

30

8342

500

21[f]

Ru-5

Triglyme/H2O (15/10)

2799

90/10

91

10,283

360

  1. General conditions: 113 mmol HCOOK, 0.009 mol% metal-catalyst (10 µmol, 88 ppm), Solvent/H2O (25 mL total), 60 °C, 6 h. [a] HCOONa. [b] 13 h. [c] 275 mmol HCOOK. [d] 90 °C. [e] 0.0004 mol% Ru-5 (1 µmol, 3.6 ppm). [f] 46 h. Volume and content of the gas phase were analyzed by manual burettes and gas chromatography (GC), respectively, after correction by the blank volume. CO is not detectable in all cases (CO quantitation limit of applied GC is <10 ppm). Yield of H2 is calculated by (mmol H2)/(mmol HCOOK)·100%. TON of H2 is calculated by (mmol H2)/(mmol catalyst). All experiments were performed at least twice; average values are shown (St. Dev.<10%). dppe: 1,2 bis(diphenylphosphino)ethane; dppm: bis(diphenylphosphino)methane; TPPTS: Triphenylphosphine-3,3′,3′′-trisulfonic acid trisodium salt.
Back to article page