Production of acrylic acid and ethanol from carbonaceous materials
A process for producing acrylic acid from carbonaceous materials such as biomass. The carbonaceous material, such as biomass, is gasified to produce synthesis gas. The synthesis gas then is subjected to a plurality of reactions to produce acrylic acid.
1. A process for producing acrylic acid and ethanol from biomass comprising:
(a) contacting said biomass with an oxidizing gas comprising oxygen and steam at a temperature of at least 550° C. and no greater than 800° C., thereby oxidizing said biomass;
(b) treating at least a portion of said oxidized biomass produced in step (a) with an oxidizing gas comprising oxygen and steam to heat said oxidized biomass to a temperature which is at least 800° C. and does not exceed a maximum of 850° C.;
(c) treating at least a portion of said oxidized biomass produced in step (b) with an oxidizing gas comprising oxygen and steam to heat said oxidized biomass to a temperature which is at least 900° C. and does not exceed a maximum of 1000° C., thereby producing a crude synthesis gas;
(d) purifying the crude synthesis gas to provide a purified synthesis gas;
(e) reacting at least a portion of the carbon monoxide from said purified synthesis gas with hydrogen from said purified synthesis gas to provide methanol;
(f) reacting said methanol in the presence of a dehydration catalyst to produce dimethyl ether;
(q) reacting said dimethyl ether to provide a product comprising propylene and ethylene;
(h) reacting said ethylene to produce ethanol; and
(i) subjecting said propylene to one or more reaction steps to produce acrylic acid.
2. The process of claim 1 wherein, in step (c), said biomass is heated to a temperature of from about 925° C. and no greater than 975° C.
3. The process of claim 1 wherein, in step (e), said carbon monoxide and said hydrogen are reacted in the presence of a methanol synthesis catalyst.
4. The process of claim 1 wherein said dimethyl ether is reacted in the presence of an acid catalyst.
5. The process of claim 4 wherein said acid catalyst is selected from the group consisting of zeolites and gamma alumina.
6. The process of claim 1 wherein, in step (i), said propylene is reacted in a partial oxidation reactor to produce acrylic acid in the presence of a cobalt and nickel molybdate based catalyst.
7. The process of claim 1 wherein, in step (i), said propylene is oxidized to produce acrolein, and said acrolein is reacted in an oxidation reactor to produce acrylic acid.
8. The process of claim 1 wherein, prior to step (a), said biomass is admixed with at least one additive material which neutralizes impurities which may be present in said biomass.
9. The process of claim 8 wherein said impurities are selected from the group consisting of chlorine, fluorine, and sulfur.
10. The process of claim 8 wherein said at least one additive material is at least one adsorbent material.
11. The process of claim 10 wherein said at least one adsorbent material is selected from the group consisting of calcium oxide, calcined limestone, ash materials, olivine, and mixtures of calcium and magnesium oxides.
12. The process of claim 1 wherein steps (a) and (b) are conducted in a gasifier, said gasifier having a fluidized bed section and a freeboard section, and wherein step (a) is conducted in said fluidized bed section and step (b) is conducted in said freeboard section.
13. The process of claim 12 wherein step (c) is conducted in one or more tubular flow reactors.