Process For The Production Of Lignin Derived Low Molecular Products

1 . A sulfonated low molecular weight aromatic compound, wherein said compound corresponds in structure to Formula (X), (XI), (XII), (XIII), (XIV) or (XV):

wherein each R 1 , R 2 , R 3 or R 4 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; halogen; optionally substituted amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl; cyanide and sulfonyl (—SO 3 H),

provided that at least one of R 1 -R 4 is SO 3 H;

wherein each R 1 , R 2 , R 3 , R 4 , R 5 or R 6 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; halogen; optionally substituted amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl; cyanide and sulfonyl (—SO 3 H),

provided that at least one of R 1 -R 6 is SO 3 H;

wherein each R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 or R 8 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; halogen; optionally substituted amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl; cyanide and sulfonyl (—SO 3 H),

provided that at least one of R 1 -R 8 is SO 3 H.

2 . The sulfonated low molecular weight aromatic compound according to claim 1 , wherein said compound corresponds in structure to Formula (X) or (XI) and wherein R 1 and R 4 are independently selected from H and SO 3 H, R 2 is selected from H, OH, and C 1 -C 6 alkoxy, or SO 3 H, R 3 is selected from H, OH and C 1 -C 6 alkoxy.

3 . The sulfonated low molecular weight aromatic compound according to claim 1 , wherein the compound corresponds in structure to Formula (X) or (XI) and wherein:

a) R 4 is SO 3 H;

b) R 4 is SO 3 H, R 3 is methoxy;

c) R 4 is SO 3 H, R 2 and R 3 are methoxy;

d) R 1 and R 4 are SO 3 H;

e) R 1 and R 4 are SO 3 H, R 3 is methoxy;

f) R 1 and R 4 are SO 3 H, R 2 and R 3 are methoxy; or

g) R 2 and R 4 are SO 3 H, and R 3 is methoxy,

wherein each of the other of R 1 -R 4 is OH or H.

4 . The sulfonated low molecular weight aromatic compound according to claim 1 , wherein said compound corresponds in structure to Formula (XII) or (XIII), wherein R 1 and R 2 are independently selected from H, OH and C 1 -C 6 alkoxy, and R 3 -R 6 are independently selected from H and SO 3 H.

5 . The sulfonated low molecular weight aromatic compound according to claim 1 , wherein said compound corresponds in structure to Formula (XIV) or (XV) and wherein R 1 , R 2 and R 4 are independently selected from H, OH and C 1-6 alkoxy, and R 3 , R 5 -R 8 are independently selected from H and SO 3 H.

6 . The sulfonated low molecular weight aromatic compound according to claim 1 , wherein the compound corresponds in structure to Formula (XIV) or (XV), wherein:

a) R 1 is SO 3 H;

b) R 2 is SO 3 H;

c) R 6 is SO 3 H;

d) R 2 and R 6 are SO 3 H;

e) R 3 and R 6 are SO 3 H;

f) R 2 and R 7 are SO 3 H; or

g) R 1 and R 4 are SO 3 H;

wherein each of the other of R 1 -R 8 is/are C 1-6 alkoxy or H.

7 . The sulfonated low molecular weight aromatic compound according to claim 1 , said compound corresponding in structure to Formula (XIV) or (XV), wherein R 1 and R 2 are, each independently or both, not selected from hydrogen; hydroxy or sulfonyl.

8 . The sulfonated low molecular weight aromatic compound according to claim 1 , said compound corresponding in structure to Formula (X) or (XI), wherein R 1 and R 2 are, each independently or both, not selected from sulfonyl.

9 . The sulfonated low molecular weight aromatic compound according to claim 1 , said compound corresponding in structure to Formula (XIV) or (XV), wherein R 1 , R 3 , R 4 are, each independently or all of them, not selected from C 1-6 alkyl.

10 . The sulfonated low molecular weight aromatic compound according to claim 9 , wherein R 1 , R 3 , R 4 are, each independently or all of them, not selected from methyl, ethyl, propyl, isopropyl, butyl, isobutyl, pentyl, hexyl and cyclohexyl.

11 . A composition comprising at least two sulfonated low molecular weight aromatic compounds according to claim 1 .

12 . The composition according to claim 11 , wherein said at least two sulfonated low molecular weight aromatic compounds are the following:

(a) at least one compound according to Formula (X) and (XI);

(b) at least one compound according to Formula (XII) and (XIII); and/or

(c) at least one compound according to Formula (XIV) and (XV).

13 . The composition according to claim 11 , said composition comprising

(a) at least two compounds according to Formula (X) and (XI), wherein said at least two compounds are distinctly sulfonated and/or substituted;

(b) at least two compounds according to Formula (XII) or (XIII), wherein said at least two compounds are distinctly sulfonated and/or substituted; and/or

(c) at least two compounds according to Formula (XIV) or (XV), wherein said at least two compounds are distinctly sulfonated and/or substituted.

14 . The composition according to claim 13 , wherein each of said at least two compounds comprises at least two SO 3 H groups.

15 . A method for preparing a sulfonated low molecular weight aromatic compound or a composition comprising the same, the method comprising the steps of

(1) providing a starting material;

(2) optionally subjecting said starting material to a process suitable to obtain at least one low molecular weight precursor compound;

(3) isolating and optionally modifying at least one low molecular weight precursor compound; thereby obtaining at least one low molecular weight aromatic precursor compound;

(4) subjecting said at least one low molecular weight precursor compound to a sulfonation reaction, wherein one or more SO 3 H groups are introduced into said at least one precursor compound; thereby obtaining at least one sulfonated low molecular weight aromatic compound or a composition comprising the same.

16 . The method according to claim 15 , wherein said starting material is lignocellulosic material and said method comprises the followings steps:

(1) subjecting lignocellulosic material to a pulping process; thereby obtaining modified lignin-derived components;

(2) isolating said modified lignin-derived components;

(3) subjecting said modified lignin-derived components to a chemical decomposition step; thereby obtaining at least one low molecular weight precursor compound;

(4) isolating and optionally modifying at least one low molecular weight precursor compound; thereby obtaining at least one low molecular weight aromatic precursor compound;

(5) subjecting said at least one low molecular weight aromatic precursor compound to a sulfonation reaction, wherein one or more —SO 3 H groups are introduced into said at least one precursor compound; thereby obtaining at least one sulfonated low molecular weight aromatic compound or a composition comprising the same.

17 . The method according to claim 15 , wherein step (1) comprises the sub-steps of:

(1.1) providing a lignocellulosic material;

(1.2) subjecting said lignocellulosic material to (a) a Kraft process or (b) a sulfite process;

(1.3) optionally separated the pulp from the process stream obtainable from the pulping process in sub-step (1.2).

18 . The method according to claim 15 , wherein step (3) comprises:

(a) oxidative cracking (cracking and oxidizing) of the modified lignin-derived components in the presence of a heterogeneous or homogeneous catalyst comprising a metal ion or a metalloid component; or

(b) reductive cracking (cracking and reducing) of the modified lignin-derived components in the presence of a heterogeneous or homogeneous catalyst comprising a metal ion or metalloid component; or

(c) subjecting the modified lignin-derived components to electro-oxidation in alkaline or acidic solution.

19 . The method according to of any one claim 15 , wherein the at least one precursor compound comprises one or two aromatic ring(s).

20 . The method of according to claim 19 , wherein the at least one precursor compound comprises two aromatic rings, wherein said two aromatic rings are linked by a linker moiety or by a bond.

21 . The method according to claim 19 , wherein the at least one precursor compound comprises two aromatic rings which form a biphenylic moiety.

22 . The method according to claim 19 , wherein the one or two aromatic ring(s) is/are carbocyclic.

23 . The method according to claim 19 , wherein the aromatic ring(s) is/are substituted in at least one position by a functional group.

24 . The method according to claim 19 , wherein the at least one precursor compound corresponds in structure to Formula (Ia):

wherein

each of R 1 -R 5 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl,

wherein at least one of R 1 , R 3 or R 5 is hydroxy or linear or branched, optionally substituted, C 1-6 alkoxy; and wherein R 6 is selected from the group consisting of hydrogen; hydroxy; linear or branched, optionally substituted, C 1-6 carboxyl; linear or branched C 1-6 aldehyde; and linear or branched, optionally substituted, C 1-6 alcohol;

or corresponds in structure to Formula (Ib):

wherein

each of R 1 -R 9 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl; and

R 10 is selected from the group consisting of hydrogen; hydroxy; linear or branched, optionally substituted, C 1-6 carboxyl; linear or branched, optionally substituted, C 1-6 aldehyde; and linear or branched C 1-6 alcohol.

25 . The method according to claim 24 , wherein the at least one precursor compound is selected from the group consisting of a phenolic derivatives of biphenyl, benzylalcohol, a benzaldehydes and benzoic acid, a derivative of any thereof, and a combination of any thereof.

26 . The method according to claim 15 , wherein step (4) comprises the sub-steps of

(4.1) isolating said precursor compound; and optionally

(4.2) subjecting said precursor compound to an annulation reaction; and/or

(4.3) subjecting said precursor compound to an oxidation reaction.

27 . The method according to claim 26 , wherein the at least one precursor compound comprises one aromatic ring and is further processed in a sub-step (4.2), wherein said precursor compound comprising one aromatic ring is subjected to an annulation reaction, wherein the annulation reaction product is a low molecular weight aromatic bi- or tricyclic annulated aromatic compound, wherein said compound corresponds in structure to Formula (II), (III) or (IV)

wherein

each of R 2 , R 3 , R 5 -R 8 of Formula (II) is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl, linear or branched, optionally substituted; C 1-6 alcohol, linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl;

and

R 1 and R 4 of Formula (II) is/are selected from the group consisting of hydrogen; hydroxy; linear or branched, optionally substituted, C 1-6 carboxyl; linear or branched, optionally substituted, C 1-6 aldehyde; and linear or branched, optionally substituted, C 1-6 alcohol;

each of R 1 -R 10 of Formula (III) is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl.

28 . The method according to claim 26 , wherein the at least one monocyclic or (optionally annulated) bi- or tricyclic precursor compound obtained from any one of sub-steps (4.1) or (4.2) is further modified in a sub-step (4.3) by oxidizing said at least precursor compound in the presence of (i) an oxidizing agent selected from the group consisting of H 2 O 2 , O 2 and air, and (ii) a homogeneous or heterogeneous catalyst.

29 . The method according to claim 28 , wherein the at least one oxidized monocyclic precursor compound obtained from any one of sub-steps (4.1) or (4.3) comprises at least one hydroquinone compound corresponding in structure to Formula (Va):

wherein each of R 1 -R 5 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl,

or corresponding in structure to formula (Vb),

wherein each of R 1 -R 9 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl,

and/or

at least one quinone compound corresponding in structure to any of Formulae (VIa) to (VIb):

wherein each of R 1 -R 2 and R 4 -R 5 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters, oxo and carbonyl; or

wherein each of R 2 -R 5 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl; or

wherein each of R 1 -R 4 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters; oxo and carbonyl; or

wherein each of R 1 -R 4 and R 6 -R 9 is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters, oxo and carbonyl.

30 . The method according to claim 28 , wherein the at least one oxidized (optionally annulated) bi- or tricyclic precursor compound obtained from any one of sub-steps (4.1)-(4.3) comprises at least one quinone and/or hydroquinone compound corresponding in structure to any of Formula (VII), (VIII) and/or (IX):

wherein each of R 1 -R 8 with regard to Formula (VII) and/or each of R 1 -R 10 with regard to Formula (VIII) and (IX) is independently selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acids; esters, oxo and carbonyl;

wherein at least one of R 8 and R 5 or R 1 and R 4 of Formula (VII) are hydroxy or oxo, or at least one of R 9 and R 6 , R 10 and R 5 , or R 1 and R 4 of Formula (VIII) are hydroxy or oxo, or at least one of R 10 and R 7 or R 1 and R 4 of Formula (IX) are hydroxy or oxo.

31 . The method according to claim 15 , wherein step (4) further comprises a purification sub-step (4.4) to separate the at least one precursor compound from residual compounds by an extraction method.

32 . The method according to claim 15 , wherein the at least one precursor compound is further subjected to a derivatization step (4.5), wherein one or more hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acid; ester; halogen; amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl or cyanide groups are introduced into a compound according to any of Formulae (I) to (IX) at a position of the aryl structure other than those characterized by an oxo or hydroxyl group, wherein said group(s) is/are directly bound to the aryl structure or bound via an alkyl linker to the aryl structure, preferably via a methyl linker.

33 . The method according to claim 15 , wherein step (5) comprises introducing one or more SO 3 H-groups into a compound according to any of Formulae (I) to (IX) at a position of the aryl structure other than those characterized by an oxo or hydroxyl group, wherein said group(s) is/are directly bound to the aryl structure or bound via an alkyl linker to the aryl structure.

34 . The method according to claim 15 , wherein the at least one sulfonated low molecular weight aromatic compound is further subjected to a derivatization step (6), wherein one or more groups selected from hydrogen; hydroxy; carboxy; linear or branched, optionally substituted, C 1-6 alkyl; linear or branched, optionally substituted, C 1-6 alkenyl; linear or branched, optionally substituted, C 1-6 alcohol; linear or branched, optionally substituted, C 1-6 aminoalkyl; linear or branched, optionally substituted, C 1-6 carboxyalkyl; linear or branched, optionally substituted, C 1-6 alkoxy; linear or branched, optionally substituted, C 1-6 aldehyde; carboxylic acid; ester; halogen; amine; amino; amide; nitro; oxo; carbonyl; phosphoryl; phosphonyl and a cyanide group are introduced into said compound, wherein said group(s) is/are directly bound to the aryl structure or bound via an alkyl linker to the aryl structure.

35 . The method according to claim 15 , further comprising a step (7) of isolating said at least one sulfonated (and optionally further derivatized) low molecular weight aromatic compound or a composition comprising the same.

36 . The method according to claim 15 , further comprising after step (5), (6) or (7) a step (8) of providing said one sulfonated (optionally further derivatized) low molecular weight aromatic compound or a composition comprising the same as a redox flow battery electrolyte.

37 . A sulfonated (and optionally further derivatized) low molecular weight aromatic compound or a composition comprising the same, obtainable by a method according to claim 15 .

38 . (canceled)

39 . A redox flow battery electrolyte solution comprising the sulfonated (and optionally further derivatized) low molecular weight aromatic compound or composition according to claim 1 dissolved or suspended in a suitable solvent.

40 . (canceled)

41 . A redox flow battery comprising the sulfonated and optionally further derivatized low molecular weight aromatic compound or the composition according to claim 1 or an electrolyte solution comprising the sulfonated and optionally further derivatized low molecular weight aromatic compound.

42 . (canceled)

43 . The sulfonated low molecular weight aromatic compound according to claim 1 , wherein said compound is selected from a sulfonated compound listed in Tables 1, 2 and 3.

44 . The method according to claim 15 , wherein said starting material is selected from the group consisting of lignocellulosic material, crude oil, coal and a pure organic substance.

45 . The method according to claim 19 , wherein the at least one precursor compound comprises two non-annulated aromatic rings.

46 . The method according to claim 31 , wherein the at least one precursor compound is a quinone or hydroquinone compound and the extraction method is a solid phase extraction or fluid-fluid phase extraction.