Process for producing hydrogen from methanol
The invention is directed to a process for producing hydrogen from methanol, comprising providing at least one flow of methanol and (1) catalytically converting part of the methanol or a fuel gas with air oxygen to carbon dioxide and water, while generating heat and (2) catalytically converting the methanol or the remaining part of the methanol at elevated temperature to hydrogen and carbon monoxide, followed by conversion of the carbon monoxide with water to hydrogen and carbon dioxide, wherein the heat generated in step (1) is sufficient to produce the elevated temperature required in step (2), wherein both steps (1) and (2) are carried out in a bed of sintered metal particles, the bed of sintered metal in step (2) having a surface that is catalytically active for the conversion of methanol to hydrogen, and wherein the beds of sintered metal particles are in heat exchanging relationship.
1. Process for producing hydrogen from methanol, comprising providing at least one flow of methanol and
(1) catalytically converting part of the methanol or a fuel gas with air oxygen to carbon dioxide and water, while generating heat and
(2) catalytically converting the methanol or the remaining part of the methanol at elevated temperature to hydrogen and carbon monoxide, followed by conversion of the carbon monoxide with water to hydrogen and carbon dioxide,
wherein the heat generated in step (1) is sufficient to produce the elevated temperature required in step (2), wherein both steps (1) and (2) are each carried out in a bed of sintered metal particles, the bed of sintered metal in step (2) having a surface that is catalytically active by catalyst applied to the surface of the sintered metal for the conversion of methanol to hydrogen, and wherein the bed of sintered metal particles used in step (1) and the bed of sintered metal particles used in step (2) are in heat exchanging relationship.
2. Process according to claim 1 , wherein a reactor is used comprising at least two beds of sintered metal particles, the first bed for step (1) being separated from the second bed for step (2) through a heat exchanging wall, and wherein in the first bed the conversion of methanol or fuel gas with air oxygen takes place and in the second bed the production of hydrogen from methanol occurs.
3. Process according to claim 2 , wherein a separate water flow is introduced into the second bed, together with the methanol.
4. Process according to claim 1 , wherein the said two steps are carried out consecutively in a first bed and a second bed downstream of the first bed and wherein methanol and air are introduced into the first bed to convert part of the methanol to generate heat for step (2), and subsequently transferring the reaction mixture containing unconverted methanol to the second bed, and wherein the two beds are in heat exchanging relationship.
5. Process according to claim 1 , wherein the sintered metal is selected from the group of copper and copper alloys.
6. Process according to claim 1 , wherein the temperature in the first and the second step is at least 150°.
7. Process according to claim 1 , wherein the catalyst in step (1) is a precious metal catalyst.
8. Process according to claim 1 , wherein the catalyst in step (2) is based on copper on zinc oxide.
9. Process according to claim 1 , wherein the pressure is between about atmospheric and about 20 bar(a).
10. Process according to claim 1 , wherein carbon monoxide in the hydrogen produced in step (2) is removed by catalytic oxidation.