Efficient and selective chemical recycling of carbon dioxide to methanol, dimethyl ether and derived products

1. An environmentally beneficial method of reducing the carbon dioxide content of the atmosphere and preparing a renewable fuel by separating and chemically recycling carbon dioxide from a natural or chemical source that would otherwise be present in or discharged into the atmosphere, which method comprises:

separating the carbon dioxide from such source and producing methanol by hydrogenatively converting the carbon dioxide thus separated under conditions sufficient to produce methanol;

utilizing the methanol thus produced as an energy storage and transportation material or as a fuel sufficient to generate energy while producing an exhaustion stream of the combustion that contains carbon dioxide; and

recovering the carbon dioxide content of the combustion stream for use as the chemically recyclable source of carbon dioxide for preparing additional fuel.

2. The method of claim 1 , wherein the carbon dioxide obtained from such source is hydrogenatively converted to methanol or derived products by catalytic, photochemical or electrochemical processes.

3. The method of claim 1 wherein the methanol is produced by hydrogentatively converting the carbon dioxide to form a reaction mixture that contains methanol, formic acid and formaldehyde, followed, without separation of the reaction mixture, by a treatment step conducted under conditions sufficient to convert the formaldehyde and formic acid to methanol.

4. The method of claim 3 , which comprises reacting the formaldehyde with the co-formed formic acid as a hydrogen source, without separation of the reaction mixture, into methanol, including reacting of the formic acid with methanol to form methyl formate, followed by hydrogenating the methyl formate under conditions sufficient to form double the staffing amount of methanol.

5. The method of claim 4 , wherein the hydrogen needed for the hydrogenation of methyl formate is obtained at least some part from cleavage of the formic acid from the reaction mixture.

6. The method of claim 1 , wherein the hydrogen needed for the hydrogenative conversion of carbon dioxide is obtained by the reforming of methane or natural gas or by electrolysis of water using an available energy source.

7. The method of claim 1 , wherein the available source of carbon dioxide is an exhaust stream from a fossil fuel burning power or industrial plant or a source accompanying natural gas and the available source would otherwise be released into the atmosphere or stored by sequestration underground or in the seas.

8. The method of claim 1 wherein the available source of carbon dioxide is the atmosphere with the carbon dioxide obtained by absorbing atmospheric carbon dioxide onto a suitable adsorbent followed by treating the adsorbent to release the adsorbed carbon dioxide therefrom.

9. The method of claim 8 , wherein the adsorbent is treated by sufficient heating to release the adsorbed carbon dioxide.

10. The method of claim 8 , wherein the adsorbent is treated by subjecting the adsorbent to sufficient reduced pressure to release the adsorbed carbon dioxide.

11. The method of claim 1 , wherein the utilizing step further comprises dehydrating methanol under conditions sufficient to produce dimethyl ether; using the dimethyl ether as is or to generate the fuel; and recycling the carbon dioxide formed by combusting the generated fuel.

12. The method of claim 11 , which further comprises utilizing the methanol or dimethyl ether as convenient energy storage and transportation materials in order to minimize or eliminate the disadvantages or dangers inherent in the use and transportation of hydrogen, LNG or LPG.