ENERGY-EFFICIENT AND ENVIRONMENTALLY FRIENDLY PROCESS FOR THE PRODUCTION OF TARGET CHEMICAL COMPOUNDS FROM CELLULOSIC MATERIAL

Abstract

The present invention is directed to an energy-efficient and environmentally friendly process for the production of chemical target compounds from cellulosic material. In a further aspect, the present invention is directed to a system for conducting the process according to the inventive process.

Claims

1. A process for the production of chemical target compounds from cellulosic material comprising the steps: a) treating cellulosic material by applying steam; b) separating the steam containing at least one chemical target compound from the treated cellulosic material; c) transferring the separated steam to a segregation device; d) segregating the phase containing the least one chemical target compound from the steam; e) subjecting the steam to a utilization step.

2. The process of claim 1, wherein the segregation is carried out by rectification, adsorption or gas-permeation,

3. The process of claim 1, wherein the segregation comprises steam transformation of the steam containing the at least one chemical target compound.

4. The process of claim 3, wherein the segregation comprises decanting the phase containing the at least one chemical target compound from the transformed steam.

5. The process of claim 4, wherein the residual watery phase is recycled to step d) after decanting the phase containing the at least one chemical target compound.

6. The process of claim 1, wherein the utilization step e) is selected from evaporation, drying, heating, sterilizing, energy generating and distillation.

7. The process of claim 1, further comprising the step: f) condensing the utilized steam of step e).

8. The process of claim 1, further comprising the step: g) recycling of the utilized steam.

9. The process of claim 8, wherein the utilized steam is recycled to step a) of the process.

10. The process of claim 1, wherein the segregated chemical compound according to step d) is one or more compounds selected from the group consisting of phenolic compounds, furans4-OH benzyl alcohol, 4-OH benzaldehyde, 4-OH benzoic acid, trimethyl benzaldehyde, 2-furoic acid, coumaric acid, ferulic acid, phenol, guaiacol, veratrole, pyrogallol, pyrogallol mono methyl ether, vanillyl alcohol, vanillin, isovanillin, vanillic acid, isovanillic acid, homovanillic acid, veratryl alcohol, veratraldehyde, veratric acid, 2-O-triethyl gallic acid, syringyl alcohol, syringaldehyde, syringic acid, trimethyl gallic acid, homocatechol, ethyl vanillin, creosol, p-methyl anisol, anisaldehyde, anisic acid, furfural, hydroxymethylfurfural, 5-hydroxymethylfurfural, formic acid, acetic acid, levulinic acid, cinnamic acid, coniferyl aldehyde, isoeugenol, hydroquinone and eugenol.

11. A process for the production of chemical target compounds from cellulosic material comprising the steps: a) treating cellulosic material by applying steam; separating the steam containing at least one chemical target compound from the treated cellulosic material; b1) subjecting the separated steam to a utilization step; c1) transferring the stream of the utilized steam to a segregation device; d1) segregating the phase containing the least one chemical target compound from the stream of the utilized steam; g1) recycling of the stream of step d1).

12. A system for a process for the production of target chemical compounds from cellulosic material comprising: (i) a reactor for the treatment of the cellulosic material according to step a) of the process as defined by claim 1; (ii) a steam separation device for separating the steam containing at least one target chemical compound from the treated cellulosic material according to step b) of the process as defined by claim 1; (iii) a steam segregation device for segregating the phase containing the least one target chemical compound from the steam according to step d) of the process as defined by claim 1; (iv) a steam utilization device for steam energy utilization.

13. The system of claim 2, further comprising a condenser (v) for condensing the utilised steam.

14. The system of claim 12, wherein the steam segregation device (iii) comprises a rectification column.

15. The system of claim 12, wherein the steam segregation device (iii) comprises a steam transformer.

16. The system of claim 12, wherein the segregation device (iii) comprises a decanter.

17. The system of claim 12, wherein the steam utilization device (iv) is selected from the group consisting of evaporator, distillation device, drying device, heating device, turbine and nozzle.

Description

EXAMPLE AND FIGURES

[0086] The present invention is now described by the following example and figures. The example and figures are for illustrative purposes only and are not to be understood as limiting the invention.

[0087] FIG. 1 shows an exemplary system and respective process of the present invention.

[0088] FIG. 2A shows the segregation device and in- and out-going process streams.

[0089] FIG. 2B shows a preferred embodiment of the segregation device and respective process-detail comprising three different segments.

[0090] FIG. 3 shows an exemplary system and respective process of the process variant of the present invention.

[0091] FIG. 4 shows the relative furfural content before and after adsorption as well as the furfural yield according to the inventive process as described within example 1

[0092] FIG. 1 illustrates a typical system for carrying out the process of the present invention wherein the treatment reactor (1) is fed by three process streams, the stream containing the cellulosic material (1A), the stream containing steam (1B) and the stream containing process water (1C) which may be recycled steam condensate from the steam usage device (4). The steam-containing treated cellulosic material is then transferred by another process stream (1D) to a steam separation device (2). Two process streams emerge from the steam separation device (2), the stream of treated cellulosic material (2A) and the stream containing steam and the at least one chemical target compound (2B). The stream containing the at least one chemical target compound (2B) is then transferred to a steam segregation device (3). Two process streams emerge from the steam segregation device (3), the stream containing the at least one chemical target compound (3A) and the stream containing the remaining purified steam (3B). The stream containing the remaining purified steam (3B) is then further transferred to a steam utilization device (4) and from the steam utilization device (4), the condensed steam (4A) is recycled to the treatment reactor (1) to be used as process water.

[0093] FIG. 2A shows the segregation device (3) and in- and out-going process streams: the steam process stream (2B) from the separation device, the outgoing process stream (3A) comprising the at least one chemical target compound and the outgoing process stream (3B) which constitutes the purified steam (steam depleted by the at least one chemical target compound).

[0094] FIG. 2B shows a preferred embodiment of the segregation device (3). Within this preferred embodiment the segregation device (3) comprises three different segments such as a rectification column (first segment) (3.1), a steam transformer (second segment) (3.2) and a decanter (third segment) (3.3). Within this preferred embodiment, the stream (3.1A) comprising the at least one chemical target compound coming from the rectification column (3.1) is transferred to a condenser (3.2) such as e.g. a steam transformer and the condensed steam/process stream (3.2 A) coming from the condenser (3.2) is then transferred to a decanter (3.3) by which the phase/stream containing the at least one chemical target compound (3A) and the remaining watery stream (3.3A) are separated. Stream (3D) is then recycled to the rectification column (3.1).

[0095] FIG. 3 illustrates a typical system for carrying out the process variant of the present invention wherein the treatment reactor (1) is fed by three process streams, the stream containing the cellulosic material (1A), the stream containing steam (1B) and the stream containing process water (1C) which may be recycled steam condensate from the steam utilization device (4). The steam-containing treated cellulosic material is then transferred by another process stream (1D) to a steam separation device (2). Two process streams emerge from the steam separation device (2), the stream of treated cellulosic material (2A) and the stream containing steam and the at least one chemical target compound (2B). The stream (2B) is then transferred to a steam utilization device (4). Within the steam utilization device (4), the steam condenses due to utilization and emerges as stream containing the at least one chemical target compound (4C). The stream containing the at least one chemical target compound (4C) is then transferred to the segregation device (3). Two process streams emerge from the segregation device (3), the stream containing the at least one chemical target compound in increased concentration (3Ai) and the purified watery stream (3C). The purified watery stream (3C) is then recycled to the treatment reactor (1) to be used as process water.

Example 1

[0096] Cereal straw with a dry matter content of 45% was treated by steam explosion (220° C).The steam recovered during the pretreatment contained a certain amount of furfural. Furfural was recovered from the steam using an adsorption column (Gassner Glastechnik, Deutschland) as segregation device containing 500 g zeolite as adsorber material (ZSM-5, H-Form, SiO.sub.2/Al.sub.2O.sub.3=1000; inert binding agent, producer: Clariant AG). To this aim, the steam was pumped through the adsorption column at a rate of 0.5 L/min for 5 h. The furfural content of the steam before and after the adsorption was determined by gas chromatography. The furfural content in the steam decreased to 54.3% thus resulting in a furfural yield of 45.7%. The results are shown within FIG. 4.