HYDROGEN STORAGE BY MEANS OF DERIVATIVES OF COMPOUNDS OF RENEWABLE ORIGIN

Abstract

The present invention relates to the use of a formulation which is liquid at ambient temperature comprising at least one terpene derivative for the fixing and the release of hydrogen in at least one hydrogenation/dehydrogenation cycle of said formulation.

The invention also relates to the use of said formulation for the transportation and the handling of hydrogen resulting from the steam cracking of petroleum products, of inevitable hydrogen resulting from chemical reactions, such as the electrolysis of salt, or of hydrogen resulting from the electrolysis of water.

Claims

1-10. (canceled)

11. A method of storing hydrogen comprising fixing the hydrogen with a formulation which is liquid at ambient temperature comprises at least one terpene derivative for the fixing and the release of the hydrogen in at least one hydrogenation/dehydrogenation cycle of said formulation.

12. The method as claimed in claim 11, in which the terpene derivative is a product of renewable origin comprising at least one hydrocarbon ring comprising 6 carbon atoms and capable of being hydrogenated and/or dehydrogenated.

13. The method as claimed in claim 11, in which the terpene derivative is an organic compound comprising at least one carbon backbone of formula (1): ##STR00006## in which each “C” represents a carbon atom, bonded to at least one other carbon atom, the total number of carbon atoms of the backbone of formula (1) being 10, said carbon backbone of formula (1) not showing the hydrogen atom(s) and/or other substituents, nor the possible unsaturation(s) in the form of double or triple bond(s) or other possible fused and/or condensed ring(s).

14. The method as claimed in any claim 11, in which the terpene derivative present in the formulation as such or by chemical reaction between two or more of them and/or with other molecules of renewable or nonrenewable origin is selected from the group consisting of: limonene, including its enantiomeric forms and its racemate (1-methyl-4-(1-methylvinyl)cyclohexene, CAS 7705-14-8, 138-86-3; 5989-27-5; 5989-54-8), terpinenes (including α-terpinene, β-terpinene, γ-terpinene) and terpinolenes, including their monohydroxylated and dihydroxylated forms, para-cymene (CAS 99-87-6) and its hydroxylated derivatives carvacrol and thymol, eucalyptol or cineol, pinenes, comprising α-pinene (CAS 7785-26-4) and β-pinene (CAS 127-91-3), and also their hydroxylated derivatives, carenes (3,7,7-trimethylbicyclo [4,1,0]heptene) and in particular Δ.sup.3-carene (CAS 13466-78-9),cadalanes (4,7-dimethyl-1-propan-2-yl-perhydronaphthalene), cadinenes (4,7-dimethyl-1-propan-2-yl-1,2,4a,5,8,8α-hexahydronaphthalene, CAS 29350-73-0), including their α-, β-, γ-, δ- and ε-stereoisomers, cannabinol and its derivatives, such as tetrahydrocannabinol, cannabidiol, cannabitriol, and others, as well as the mixtures of two or more of them.

15. The method as claimed in claim 11, in which the terpene derivative originates from terrestrial, marine or submarine plants.

16. The method as claimed in claim 11, in which the terpene derivative originates from plants selected from the group consisting of sage, rosemary, lavender, pepper, clove, hemp, cannabis, camphor, hops, cinnamon, basil, oregano, citrus fruits (lemon, orange, citron), mint, peppermint, juniper, cade juniper, ginger, ginseng, bay leaf, lemon grass, mango, dill, parsley, thyme, watercress, monarda, savory, marjoram, dittany, eucalyptus, tea tree, cumin, artemisia, and absinthe.

17. The method as claimed in claim 11, in which the formulation additionally comprises one or more other LOHCs and their mixtures in all proportions.

18. The method as claimed in claim 11, in which the formulation exhibits a boiling point of greater than 150° C., at atmospheric pressure and a melting point of less than 40° C.

19. The method as claimed in claim 11, in which the formulation exhibits a kinematic viscosity at 20° C. (measured according to the standard DIN 51562) of between 0.1 mm.sup.2.Math.s.sup.−1 and 500 mm.sup.2.Math.s.sup.−1.

20. The method as claimed in claim 11, for the transportation and the handling of hydrogen resulting from the steam cracking of petroleum products, of inevitable hydrogen resulting from chemical reactions, such as the electrolysis of salt, or of hydrogen resulting from the electrolysis of water.

Description

[0043] According to a preferred embodiment of the invention, the terpene derivatives which can be used in the context of the present invention exhibit a TGSC of strictly greater than 0%, preferably of greater than or equal to 1%, better still of greater than or equal to 2%, more preferably of greater than or equal to 3%, advantageously of greater than or equal to 4% and very advantageously of greater than or equal to 5%.

[0044] In certain cases, and according to an embodiment of the present invention, it can be advantageous to modify, for example increase, the TGSC of the LOHCs, and more advantageously while maintaining a ratio of carbon of renewable origin of greater than or equal to 20%, as indicated above. It is consequently possible to envisage causing the terpene derivatives to react chemically with one another and/or with other molecules of renewable or nonrenewable origin, for example molecules resulting from petrochemicals, in particular aromatic compounds resulting from petrochemicals, such as benzene, toluene, xylenes, benzene/toluene/xylene mixtures better known under the names of BTX, polyethylbenzene residues better known under the name PEBR, and also their mixtures in all proportions, to mention only the commonest.

[0045] By way of example, it is thus possible to carry out couplings starting from halogenated, in particular chlorinated, or hydroxylated derivatives, according to procedures well known to a person skilled in the art and in particular those described in the patent DE2840272 A1, in the publication by Maria Sol Marques da Silva et al., Reactive Polymers, 25, (1995), 55-61, or also more recently in the paper by Taiga Yurino et al., European Journal of Organic Chemistry, (2020), 2020(15), 2225-2232.

[0046] Thus, an example of coupling can be carried out between cymene and benzyl chloride to result in a new LOHC terpene derivative with a TGSC equal to 5.9%:

##STR00004##

[0047] According to another example, it is possible to carry out a coupling between cymene and tolyl chloride to result in another new LOHC terpene derivative, the TGSC of which exhibits the same value of 5.9%:

##STR00005##

[0048] In one embodiment of the present invention, preference is given to terpene derivatives exhibiting (in their theoretically completely dehydrogenated form) at least two six-membered rings, preferably at least two six-membered carbon rings, more preferably at least two aromatic rings having six carbon atoms.

[0049] The invention thus relates to the use of a formulation which is liquid at ambient temperature, in its partially or completely dehydrogenated form, as in its partially or completely hydrogenated form, comprising one or more terpene derivatives as they have just been defined for the fixing and the release of hydrogen in at least one partial or complete hydrogenation/dehydrogenation cycle of said formulation.

[0050] The formulation which can be used in the context of the present invention can additionally comprise one or more other LOHCs known to a person skilled in the art, such as, for example, chosen from toluene, benzyltoluene (BT), dibenzyltoluene (DBT) and their mixtures in all proportions.

[0051] The formulation which can be used in the present invention can additionally comprise one or more additive(s) and/or filler(s) also well known to a person skilled in the art and, for example, and in a nonlimiting way, chosen from antioxidants, passivators, pour point depressants, decomposition inhibitors, colorants, aromas, and the like, and also the mixtures of one or more of them in all proportions.

[0052] According to another embodiment, and according to the requirements in particular in terms of purity of hydrogen to be released, the formulation comprises only (partially or completely) hydrogenatable/dehydrogenatable compounds; in particular, the formulation consists of LOHC molecules, without other added products of additive or filler types. The formulation may, however, contain impurities, preferably in trace form, in particular inherent in the origin of the LOHC molecule used and/or its process of preparation.

[0053] According to a preferred embodiment of the present invention, the formulation exhibits a boiling point of greater than 150° C. at atmospheric pressure, preferably of greater than 180° C. at atmospheric pressure, and a melting point of less than 40° C., preferably of less than 30° C., more preferably of less than 20° C., better still of less than 15° C., and entirely preferably a melting point of less than 10° C. and advantageously of strictly less than 0° C.

[0054] According to another embodiment, the formulation used in the present invention exhibits a kinematic viscosity at 20° C. (measured according to the standard DIN 51562) of between 0.1 mm.sup.2.Math.s.sup.−1 and 500 mm.sup.2.Math.s.sup.−1, preferably between 0.5 mm.sup.2.Math.s.sup.−1 and 300 mm.sup.2.Math.s.sup.−1 and preferably between 1 mm.sup.2.Math.s.sup.−1 and 200 mm.sup.2.Math.s.sup.−1.

[0055] According to yet another embodiment, the flash point of the formulation comprising at least one terpene derivative according to the invention exhibits a flash point of greater than 10° C., preferably of greater than 20° C., measured according to the standard NF EN 22-592.

[0056] In a very particularly preferred embodiment of the invention, the formulation, and in particular each of the elements which compose it, exhibits a decomposition temperature of greater than 250° C. and advantageously does not decompose to more than 0.1% by weight, when said formulation is maintained at a temperature of 300° C. for 4 hours, at atmospheric pressure. This precaution makes it possible to envisage a maximum rate of reuse of the LOHC formulation, which is intended to be the subject of as great a number as possible of hydrogenation/dehydrogenation cycles, for example at least 50 times, advantageously at least 100 times, more advantageously at least 250 times, thus making possible the storage and transportation of hydrogen with said formulation.

[0057] The hydrogenation/dehydrogenation cycles are generally carried out according to methods which are now well known. In particular, the dehydrogenation reaction can be carried out according to any known method, by applying one or more of the following operating conditions, which operating conditions are listed below by way of nonlimiting examples: [0058] reaction temperature generally of between 200° C. and 350° C., preferably between 250° C. and 330° C., more preferably between 280° C. and 320° C., more preferentially between 280° C. and 330° C. and completely preferably between 280° C. and 320° C., [0059] reaction pressure generally of between 0.001 MPa and 0.3 MPa and preferably between 0.01 MPa and 0.2 MPa, and more preferably the reaction pressure is atmospheric pressure, [0060] feeding the dehydrogenation reactor with a partial hydrogen pressure, —halting the reaction before complete dehydrogenation of the compound(s) to be dehydrogenated.

[0061] The reaction is generally and advantageously carried out in the presence of at least one dehydrogenation catalyst well known to a person skilled in the art. Mention may be made, among the catalysts which can be used for said partial dehydrogenation reaction, by way of nonlimiting examples, of heterogeneous catalysts containing at least one metal on a support. Said metal is chosen from the metals of columns 3 to 12 of the Periodic Table of the Elements of the IUPAC, that is to say from the transition metals of said periodic table. In a preferred embodiment, the metal is chosen from the metals of columns 5 to 11, more preferentially of columns 5 to 10, of the Periodic Table of the Elements of the IUPAC.

[0062] The metals of these catalysts are generally chosen from iron, cobalt, copper, titanium, molybdenum, manganese, nickel, platinum and palladium, and their mixtures. The metals are preferably chosen from copper, molybdenum, platinum, palladium and the mixtures of two or more of them in all proportions.

[0063] The support of the catalyst can be of any type well known to a person skilled in the art and is advantageously chosen from porous supports, more advantageously from porous refractory supports. Nonlimiting examples of supports comprise alumina, silica, zirconia, magnesia, beryllium oxide, chromium oxide, titanium oxide, thorium oxide, ceramic, carbon, such as carbon black, graphite and activated carbon, and also their combinations. Mention may be made, among the specific and preferred examples of a support which can be used in the process of the present invention, of amorphous aluminosilicates, crystalline aluminosilicates (zeolites) and supports based on silica-titanium oxide.

[0064] The hydrogenation reaction can also be carried out for its part according to any method well known to a person skilled in the art on a formulation comprising at least one terpene derivative as defined above.

[0065] The hydrogenation reaction is generally carried out at a temperature of between 100° C. and 200° C., preferably between 120° C. and 180° C. and more preferably from 140° C. to 160° C. The pressure employed for this reaction is generally between 0.1 MPa and 5 MPa, preferably between 0.5 MPa and 4 MPa and more preferably between 1 MPa and 3 MPa.

[0066] The hydrogenation reaction is generally carried out in the presence of a catalyst and more particularly of a hydrogenation catalyst well known to a person skilled in the art and advantageously chosen from, by way of nonlimiting examples, heterogeneous catalysts containing metals on a support. Said metal is chosen from the metals of columns 3 to 12 of the Periodic Table of the Elements of the IUPAC, that is to say from the transition metals of said periodic table. In a preferred embodiment, the metal is chosen from the metals of columns 5 to 11, more preferentially of columns 5 to 10, of the Periodic Table of the Elements of the IUPAC.

[0067] The metals of these hydrogenation catalysts are generally chosen from iron, cobalt, copper, titanium, molybdenum, manganese, nickel, platinum and palladium, and their mixtures. The metals are preferably chosen from copper, molybdenum, platinum, palladium and the mixtures of two or more of them in all proportions.

[0068] The support of the catalyst can be of any type well known to a person skilled in the art and is advantageously chosen from porous supports, more advantageously from porous refractory supports. Nonlimiting examples of supports comprise alumina, silica, zirconia, magnesia, beryllium oxide, chromium oxide, titanium oxide, thorium oxide, ceramic, carbon, such as carbon black, graphite and activated carbon, and also their combinations. Mention may be made, among the specific and preferred examples of a support which can be used in the process of the present invention, of amorphous aluminosilicates, crystalline aluminosilicates (zeolites) and supports based on silica-titanium oxide.

[0069] According to a preferred embodiment, the hydrogenation reaction is carried out on a completely or partially dehydrogenated formulation, for example at least partially dehydrogenated, in one or more hydrogenation/dehydrogenation cycles.

[0070] Similarly, the hydrogenation reaction can be partial or complete and preferably the hydrogenation reaction is complete in one or more hydrogenation/dehydrogenation cycles, that is to say that all of the double bonds capable of being hydrogenated present in the LOHC formulation are completely hydrogenated.

[0071] According to another aspect, the present invention relates to a hydrogenation/dehydrogenation cycle comprising a partial or complete dehydrogenation reaction of an LOHC formulation as has just been defined and at least one partial or complete hydrogenation reaction of said organic liquid.

[0072] According to a very particularly preferred aspect of the invention, the boiling point of said LOHC formulation is greater than the temperature required for the dehydrogenation stage, this being the case in order to obtain the purest possible hydrogen in gaseous form.

[0073] In the LOHC application, the formulations for the transportation of hydrogen, the use of which is the subject matter of the present invention, are very particularly well suited because of their stability, which makes possible reuse in a large number of hydrogenation/dehydrogenation cycles for the transportation and the handling of hydrogen resulting from the steam cracking of petroleum products, of inevitable hydrogen resulting from chemical reactions, such as the electrolysis of salt, or of hydrogen resulting from the electrolysis of water.