Catalysed process of production of hydrogen from silylated derivatives as hydrogen carrier compounds

Abstract

The present invention relates to a catalysed process of production of hydrogen from silylated derivatives as hydrogen carrier compounds. The present invention also relates to a new catalyst used in the catalysed process of production of hydrogen from silylated derivatives as hydrogen carrier compounds.

Claims

1. Method for producing hydrogen comprising contacting a hydrogen carrier compound (C) comprising one or more SiH bonds with a first hydrogen release catalyst and optionally with a second an optional hydrogen release catalyst wherein the first hydrogen release catalyst is selected from formula ##STR00035## wherein Y is O or S, and X1 and X2 are each independently selected from halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, and SiR.sup.6R.sup.7R.sup.8, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 and X2=CR.sup.aR.sup.b which form together with the carbon atom to which they are attached a 3 to 10-membered cycloalkyl, optionally substituted by one to three R.sup.9 groups and R.sup.a and R.sup.b are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 and X2=NR.sup.aR.sup.b with R.sup.a and R.sup.b each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 is selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, and SiR.sup.6R.sup.7R.sup.8 and X2=NR.sup.aR.sup.b with R.sup.a and R.sup.b each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 and X2=NR.sup.c which form together with the carbon atom to which they are attached a 3 to 10-membered heterocycloalkyl, optionally substituted by one to three R.sup.9 groups and R.sup.c is selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1=CR.sup.aR.sup.b with R.sup.a and R.sup.b each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10 and X2=NR.sup.c which form together with the carbon atom to which they are attached a 3 to 10-membered heterocycloalkyl, optionally substituted by one to three R.sup.9 groups with R.sup.c selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups wherein R.sup.3 is selected from H, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; R.sup.6, R.sup.7, and R.sup.8 are each independently selected from H, OR.sup.3, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; R.sup.9 is selected from halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.10, NO.sub.2, NR.sup.11R.sup.12, CN, C(O)R.sup.10, C(O)OR.sup.10, and S(O)CH.sub.3, wherein said alkyl and aryl groups are optionally substituted by one or more halogen or C1-C10 alkyl or OR.sup.3; R.sup.10 is selected from H, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; and R.sup.11 and R.sup.12 are each independently selected from H and C1-C10 alkyl, and wherein the ratio between the sum of the moles of the first hydrogen release catalyst and the moles of the second hydrogen release catalyst, when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst, relative to the moles of the hydrogen carrier compound (C) multiplied by the number of [SiH] bonds of compound (C) is inferior or equal to 0.3, and/or wherein the ratio between the sum of the mass of the first hydrogen release catalyst and the mass of the second hydrogen release catalyst, when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst, relative to the mass of the hydrogen carrier compound (C) is inferior or equal to 0.2.

2. Method for producing hydrogen according to claim 1, wherein the compound (C) comprises one or more monomer units of the following formulae: ##STR00036## wherein R is selected from a bond, C.sub.1-C.sub.6 alkylene and (C.sub.1-C.sub.4 alkylene)q-Z-(C.sub.1-C.sub.4 alkylene)r; Z is selected from O, NR.sup.10, S(O).sub.y, CR.sup.10CR.sup.10, CC, C6-C10 arylene, 5-10 membered heteroarylene, and C3-C6 cycloalkylene; R.sup.1 and R.sup.2 are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, NR.sup.4R.sup.5, and SiR.sup.6R.sup.7R.sup.8, wherein said aryl groups are optionally substituted by one to three R.sup.9 groups; R.sup.1 and R.sup.2 are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, NR.sup.4R.sup.5, and SiR.sup.6R.sup.7R.sup.8, wherein said aryl groups are optionally substituted by one to three R.sup.9 groups; R.sup.3 is selected from H, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; R.sup.4 and R.sup.5 are each independently selected from H, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; R.sup.6, R.sup.7, and R.sup.8 are each independently selected from H, OR.sup.3, C1-C6 alkyl, C6-C10 aryl, C6-C12 aralkyl, and SiH.sub.3; R.sup.9 is selected from halogen, C1-C10 alkyl, OR.sup.10, NO.sub.2, NR.sup.11R.sup.12, CN, C(O)R.sup.10, C(O)OR.sup.10, and S(O)CH.sub.3, wherein said alkyl group is optionally substituted by one or more halogen; R.sup.10 is H or C1-C3 alkyl; R.sup.11 and R.sup.12 are each independently selected from H and C1-C10 alkyl; q and r are 0 or 1; y is 0, 1 or 2; m, n and p are integers representing the number of repeating units, with n being superior or equal to 1, p being 0 or 1 and m being 0 or 1; A and B are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, OSiR.sup.6R.sup.7R.sup.8, NR.sup.4R.sup.5, SiR.sup.6R.sup.7R.sup.8, and CR.sup.13R.sup.14R.sup.15 wherein said aryl groups are optionally substituted by one to three R.sup.9 groups; R.sup.13, R.sup.14, and R.sup.15 are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, NR.sup.4R.sup.5, and SiR.sup.6R.sup.7R.sup.8, and wherein the compound (C) comprises at least one group Si-H.

3. Method for producing hydrogen according to claim 2 wherein, in the compound (C) formulae, p=0 and m=1; and/or R.sup.1=Me or H; and/or R.sup.1 is Me and n is superior to 1 and inferior to 15,000.

4. Method for producing hydrogen according to claim 2, wherein compound (C) is Polyhydromethylsiloxane.

5. Method for producing hydrogen according to claim 2, wherein the compound (C) comprises one or more monomer units of the following formulae ##STR00037## wherein R.sup.1 is H and n is superior to 1.

6. Method for producing hydrogen according to claim 2 wherein, in the compound (C) formulae, A=SiMe.sub.3, Me or SiH.sub.3 and B=OMe, OSiMe.sub.3 or OSiH.sub.3.

7. Method for producing hydrogen according to claim 2 wherein the compound (C) comprises one or more monomer units of the following formulae ##STR00038## wherein n is between 1 and 30.

8. Method for producing hydrogen according to claim 1 wherein the ratio between the sum of the moles of the first hydrogen release catalyst and the moles of the second hydrogen release catalyst, when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst, relative to the moles of the hydrogen carrier compound (C) multiplied by the number of [SiH] bonds of compound (C) ranges from 0.005 to 0.3, and/or wherein the ratio between the sum of the mass of the first hydrogen release catalyst and the mass of the second hydrogen release catalyst, when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst, relative to the mass of the hydrogen carrier compound (C) is between 0.01 and 0.2.

9. Method for producing hydrogen according to claim 1, wherein the ratio between the sum of the moles of the first hydrogen release catalyst and the moles of the second hydrogen release catalyst, when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst, relative to the moles of the hydrogen carrier compound (C) multiplied by the number of [SiH] bonds of compound (C) ranges from 0.01 to 0.1, and/or wherein the ratio between the sum of the mass of the first hydrogen release catalyst and the mass of the second hydrogen release catalyst, when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst, relative to the mass of the hydrogen carrier compound (C) is comprised between 0.02 and 0.07.

10. Method for producing hydrogen comprising contacting a hydrogen carrier compound (C) comprising one or more SiH bonds with a first hydrogen release catalyst and optionally with a second hydrogen release catalyst wherein the first hydrogen release catalyst is selected from the following first hydrogen release catalyst formula ##STR00039## wherein Y is O or S, and X1 and X2 are each independently selected from halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, and SiR.sup.6R.sup.7R.sup.8, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 and X2=CR.sup.aR.sup.b which form together with the carbon atom to which they are attached a 3 to 10-membered cycloalkyl, optionally substituted by one to three R.sup.9 groups and R.sup.a and R.sup.b are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 and X2=NR.sup.aR.sup.b with R.sup.a and R.sup.b each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 is selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.3, and SiR.sup.6R.sup.7R.sup.8 and X2=NRR.sup.b with R.sup.a and R.sup.b each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1 and X2=NR.sup.c which form together with the carbon atom to which they are attached a 3 to 10-membered heterocycloalkyl, optionally substituted by one to three R.sup.9 groups and R.sup.c is selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups Or X1=CR.sup.aR.sup.b where R.sup.a and R.sup.b are each independently selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10 and X2=NR.sup.c which form together with the carbon atom to which they are attached a 3 to 10-membered heterocycloalkyl, optionally substituted by one to three R.sup.9 groups with R.sup.c selected from H, halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, aralkyl, 5 to 10-membered heteroaryl, and OR.sup.10, wherein said alkyl and aryl groups are optionally substituted by one to three R.sup.9 groups wherein R.sup.3 is selected from H, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; R.sup.6, R.sup.7, and R.sup.8 are each independently selected from H, OR.sup.3, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; R.sup.9 is selected from halogen, C1-C10 alkyl, C3-C10 cycloalkyl, C6-C12 aryl, C6-C12 aralkyl, 5 to 10-membered heteroaryl, OR.sup.10, NO.sub.2, NR.sup.11R.sup.12, CN, C(O)R.sup.10, C(O)OR.sup.10, and S(O)CH.sub.3, wherein said alkyl and aryl groups are optionally substituted by one or more halogen or C1-C10 alkyl or OR.sup.3; R.sup.10 is selected from H, C1-C6 alkyl, C6-C10 aryl, and C6-C12 aralkyl; and R.sup.11 and R.sup.12 are each independently selected from H and C1-C10 alkyl, and wherein the hydrogen carrier compound (C) is selected amongst siloxane hydrogen carrier compounds comprising one or more units of formula (I): ##STR00040## wherein n is an integer superior or equal to 3 and inferior or equal to 500, and wherein the molar ratio of the sum of the {first hydrogen release catalyst and the second hydrogen release catalyst when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst} relative to the [SiOH.sub.2] monomer units in compound (C) is lower than or equal to 0.6.

11. Method for producing hydrogen according to claim 10 wherein the molar ratio of the sum of the {first hydrogen release catalyst and the second hydrogen release catalyst when the hydrogen carrier compound (C) is optionally contacted with the second hydrogen release catalyst} relative to the [SiOH.sub.2] monomer units in compound (C) ranges from 0.01 to 0.5.

12. Method for producing hydrogen according to claim 10, wherein Y is O in the first hydrogen release catalyst formula.

13. Method for producing hydrogen according to claim 10, wherein X1 is NR.sup.aR.sup.b in the first hydrogen release catalyst formula.

14. Method for producing hydrogen according to claim 10, wherein X1 and X2 are both selected from NR.sup.aR.sup.b in the first hydrogen release catalyst formula.

15. Method for producing hydrogen according to claim 10, wherein the first hydrogen release catalyst is selected from 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU), tetramethylurea, urea, N,N-dimethylacetamide, cyclohexanone, and mixtures thereof.

16. Method for producing hydrogen according to claim 10, wherein the first hydrogen release catalyst is supported.

17. Method for producing hydrogen according to claim 10, wherein the compound (C) comprises one or more monomer units of the following formulae ##STR00041## wherein n is inferior to 500.

18. Method for producing hydrogen according to claim 10, wherein the compound (C) is ##STR00042## wherein n is an integer superior or equal to one and inferior or equal to 32.

19. Method for producing hydrogen according to claim 10, wherein contacting the hydrogen carrier compound (C) with the first hydrogen release catalyst is performed in the absence of the second hydrogen release catalyst.

Description

EXAMPLES

(1) Polyhydromethylsiloxane (PHMS), Thiourea, tetramethylurea, N,N-dimethylformamide, N,N-dimethylacetamide, Cyclohexanone, Diethylether, Acetone, 1,3-diphenylurea, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU), Tetramethylthiourea and Phenylsilane are used in the following examples.

DESCRIPTION OF THE EXPERIMENTAL SET-UP

(2) A 60 mL PET preform was connected (by screwing) to a pressure tight ball lock coupler featuring an outlet nozzle for hydrogen gas evacuation and a female thread to which a stainless needle, equipped with a stainless stopcock, was crimped for reactants injection. The hydrogen gas outlet nozzle was connected, via a tee connector, on one hand to a pressure recorder in order to monitor the kinetic of the hydrogen release and on the other hand to an inverted 2 L measuring cylinder filled with water in order to measure to volume of hydrogen gas produced. The hydrogen release into the measuring cylinder was triggered by a ball valve and the hydrogen flow was controlled by a needle valve.

Comparative Example 1-C1

(3) In a 60 mL PET preform was charged 1.022 g (17.00 mmol, 1.0 equiv.) of PHMS and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.212 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 1200 seconds. When pressure increase stopped, the release on/off valve was opened and 10 mL (2,5% yield) of hydrogen gas were collected in the measuring cylinder.

Example 2

(4) In a 60 mL PET preform was charged 1.001 g (16.65 mmol, 1.0 equiv.) of PHMS and 0.062 g (0.484 mmol, 0.029 equiv.) of DMPU. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 6.5 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 300 mL (75% yield) of hydrogen gas were collected in the measuring cylinder.

Example 3

(5) In a 60 mL PET preform was charged 1.002 g (16.66 mmol, 1.0 equiv.) of PHMS and 0.053 g (0.456 mmol, 0.027 equiv.) of tetramethylurea. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 10 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 270 mL (68% yield) of hydrogen gas were collected in the measuring cylinder.

Example 4

(6) In a 60 mL PET preform was charged 1.007 g (16.75 mmol, 1.0 equiv.) of PHMS and 0.109 g (0.514 mmol, 0.031 equiv.) of diphenylurea. The suspension was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.215 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 720 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 10 mL (2,5% yield) of hydrogen gas were collected in the measuring cylinder.

Example 5

(7) In a 60 mL PET preform was charged 1.017 g (16.91 mmol, 1.0 equiv.) of PHMS and 0.036 g (0.413 mmol, 0.024 equiv.) of N,N-dimethylacetamide. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 500 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 270 mL (68% yield) of hydrogen gas were collected in the measuring cylinder.

Example 6

(8) In a 60 mL PET preform was charged 1.022 g (17.00 mmol, 1.0 equiv.) of PHMS and 0.068 g (0.781 mmol, 0.046 equiv.) of N,N-dimethylacetamide. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.212 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 30 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 310 mL (78% yield) of hydrogen gas were collected in the measuring cylinder.

Example 7

(9) In a 60 mL PET preform was charged 1.003 g (16.68 mmol, 1.0 equiv.) of PHMS and 0.036 g (0.493 mmol, 0.030 equiv.) of N,N-dimethylformamide. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium, under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 1300 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 120 mL (30% yield) of hydrogen gas were collected in the measuring cylinder.

Example 8

(10) In a 60 mL PET preform was charged 1.003 g (16.68 mmol, 1.0 equiv.) of PHMS and 0.045 g (0.591 mmol, 0.035 equiv.) of thiourea. The suspension was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 400 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 10 mL (2,5% yield) of hydrogen gas were collected in the measuring cylinder.

Example 9

(11) In a 60 mL PET preform was charged 1.000 g (16.63 mmol, 1.0 equiv.) of PHMS and 0.066 g (0.499 mmol, 0.030 equiv.) of tetramethylthiourea. The suspension was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 700 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 40 mL (10% yield) of hydrogen gas were collected in the measuring cylinder.

Example 10

(12) In a 60 mL PET preform was charged 0.063 g (0.476 mmol, 0.028 equiv.) of tetramethylthiourea and 0.707 g (9.54 mmol, 0.567 equiv.) of diethylether. The suspension was stirred vigorously until the solid dissolved. 1.012 g (16.83 mmol, 1.00 equiv.) of PHMS was then added to the PET preform. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.216 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 1500 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 320 mL (80% yield) of hydrogen gas were collected in the measuring cylinder.

Example 11

(13) In a 60 mL PET preform was charged 1.007 g (16.75 mmol, 1.0 equiv.) of PHMS and 0.056 g (0.571 mmol, 0.034 equiv.) of cyclohexanone. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.215 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 600 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 260 mL (65% yield) of hydrogen gas were collected in the measuring cylinder.

Example 12

(14) In a 60 mL PET preform was charged 0.993 g (16.51 mmol, 1.0 equiv.) of PHMS and 0.029 g (0.499 mmol, 0.0302 equiv.) of acetone. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.218 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 1400 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 80 mL (20% yield) of hydrogen gas were collected in the measuring cylinder.

Comparative Example C13

(15) In a 60 mL PET preform was charged 0.599 g (5.55 mmol, 1.0 equiv.) of phenylsilane and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.649 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and the reaction was left to run on a period of 130 sec before the release on/off valve was opened and 5 mL (0.8% yield) of H2 were collected in the measuring cylinder.

Example 14

(16) In a 60 mL PET preform was charged 0.602 g (5.56 mmol, 1.0 equiv.) of phenylsilane and 0.028 g (0.218 mmol, 0.039 equiv.) of DMPU. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.647 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 90 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 310 mL (78% yield) of hydrogen gas were collected in the measuring cylinder.

Example 15

(17) In a 60 mL PET preform was charged 0.605 g (5.59 mmol, 1.0 equiv.) of phenylsilane and 0.055 g (0.473 mmol, 0.085 equiv.) of tetramethylurea. The solution was stirred at room temperature for a few seconds and 0.6 mL of NaOH (20 wt % in water) (3.6 mmol, 0.644 equiv.) was quickly added with a 1 mL syringe via the injection needle onto the reacting medium under vigorous stirring. The stopcock was closed and a pressure increase was observed on a period of 130 seconds along with formation of a white expanded solid. When pressure increase stopped, the release on/off valve was opened and 340 mL (85% yield) of hydrogen gas were collected in the measuring cylinder.

BRIEF DESCRIPTION OF THE DRAWINGS

(18) FIG. 1 describes the evolution of the relative pressure in the system as a function of depending on the nature of the catalyst with PHMS as hydrogen carrier compound

(19) FIG. 2 describes the evolution of the relative pressure in the system as a function of time depending on the nature of the catalyst with phenylsilane as hydrogen carrier compound

(20) Table 1 gives a summary of the performances of the catalysts respectively used in examples 2 to 12 for the H2 production from PHMS

(21) TABLE-US-00001 TABLE 1 Loading Release Example Catalyst (mol %) time (s) Yield Cl 1200 10 mL (2,5%) 2 DMPU 2,9 6,5 300 mL (75%) 3 tetramethylurea 2,7 10 270 mL (68%) 4 diphenylurea 3,1 720 10 mL (2,5%) 5 N,N- dimethylacetamide 2,4 500 270 mL (68%) 6 N,N- dimethylacetamide 4,6 30 310 mL (78%) 7 N,N- dimethylformamide (DMF) 3,0 1300 120 mL (30%) 8 thiourea 3,5 400 10 mL (2,5%) 9 tetramethylthiourea 3,0 700 40 mL (10%) 10 0 Tetramethylthiourea + Et.sub.2O 2,8 1500 320 mL (80%) 11 Cyclohexanone 3,4 600 260 mL (65%) 12 Acetone 3,0 1400 80 mL (20%)

(22) Table 2 gives a summary of the performances of DMPU and Tetramethylurea as catalysts for the H.sub.2 production from. Phenylsilane

(23) TABLE-US-00002 TABLE 2 Loading Release time Example Catalyst (mol %) (s) Yield C13 130 5 mL (0,8%) 14 DMPU 3,9 90 310 mL (78%) 15 tetramethylurea 8,5 130 340 mL (85%)