METHOD FOR THE SYNTHESIS OF A HYDROGEN-LOADED LIQUID ORGANIC HYDROGEN CARRIER (LOHC) USING HYDROGEN PRODUCED FROM A METHANIZATION DISPENSE

Description

TECHNICAL FIELD

[0001] The invention relates to the field of production, storage and transport of hydrogen.

[0002] More specifically, it relates to a process for synthesizing a liquid organic hydrogen carrier, or LOHC (for Liquid Organic Hydrogen Carrier in English), loaded with hydrogen in which a methanization digestate is used as a source of hydrogen.

[0003] It also relates to a process for recovering organic waste as well as to a process for producing hydrogen which implements this synthesis process. STATE OF THE PRIOR ART

[0004] Due to its high mass energy density (33 kWh / kg) and its ability to be oxidized in the presence of oxygen in the form of pure water without releasing CO2, hydrogen is considered a significant energy vector for carrying out the energy transition, particularly by replacing fossil fuels.

[0005] While hydrogen could potentially be used as a reactant in fuel cells to generate electricity, its primary destination currently remains industry. Indeed, 75 million tonnes are consumed annually by the chemical industry, nearly 45% of which is used for oil refining.

[0006] To date, steam reforming of hydrocarbons, mainly methane, is the most widely used hydrogen production process to supply industry with hydrogen because it is by far the most economical. Steam reforming involves reacting methane with water at high temperature and in the presence of catalysts to produce a mixture of H 2 , CO 2 , CO and water. At the outlet of the steam reactor, the hydrogen is separated from the CO 2 and an excess mixture of CO, methane and water vapour (called syngas) which is used as fuel to provide the heat required for steam reforming.

[0007] However, for every tonne of hydrogen produced by steam reforming, approximately 10 tonnes of CO2 are emitted and generally released into the atmosphere.

[0008] Hydrogen production processes that limit, or even eliminate, greenhouse gas emissions, particularly CO2, are therefore being studied to supplement its production by steam reforming or even gradually replace it.

[0009] Among these processes, water electrolysis, which consists of decomposing water into oxygen and hydrogen with an electric current (which, ideally, should itself come from a low greenhouse gas emission electricity production sector such as nuclear, wind or solar), represents a technology of choice.

[0010] Two main types of electrolysis are considered, with, on the one hand, the so-called "low temperature" processes which are based on the use of proton-conducting polymer membranes (called PEM for Proton Exchange Membrane in English) and, on the other hand, the so-called "high temperature" processes which are based on the use of anionic or proton conductive ceramic membranes in SOEC systems (for Solid Oxide Electrolysis Cell in English).

[0011] However, with a view to democratising the use of hydrogen in industrial sectors other than petrochemicals, as well as in the transport and housing sectors, there are, beyond its low-carbon production, two technological obstacles to overcome, namely its storage and its transport.

[0012] Indeed, given its very low mass density, the storage and transport of hydrogen currently involves either its liquefaction at atmospheric pressure but at an extremely low temperature (-253°C) or its compression at very high pressure (70 MPa) with, in both cases, the need to control the risks linked to its propensity to leak due to its small size, its flammability, its ability to detonate and its deleterious effect on the metals and alloys used in the construction of the equipment in which it is confined.

[0013] This is why research is now focused on the development of LOHCs.

[0014] LOHCs are liquid or semi-solid organic compounds at room temperature that can be alternately charged and discharged with hydrogen viacatalytic hydrogenation and dehydrogenation reactions. LOHCs have a high hydrogen storage density and allow hydrogen to be transported safely.

[0015] Typical examples of LOHCs are aromatic hydrocarbons such as toluene and naphthalene, which, upon hydrogenation, produce methylcyclohexane and decalin. These can then be packaged for storage and / or transport to the location where they will be used to produce hydrogen by catalytic dehydrogenation. Multi-cycle hydrogenation and dehydrogenation processes can thus be carried out with these compounds – as illustrated below for the toluene / methylcyclohexane pair – without significant loss of yield.

[0016] For an update on recent developments in LOHCs, the reader is invited to refer to the article by Purna Chandra Rao and Minyoung Yoon published in Energies 2020, 13(22), 1-23).

[0017] While LOHCs clearly represent a very attractive option for storing and transporting hydrogen, their integration into an energy and ecological transition strategy requires the possibility of hydrogenating them with hydrogen from a production sector that is not only carbon-free but also inexpensive. WO 2007 / 140441 A2 discloses a hydrogen production process comprising obtaining gaseous ammonia from a methanization digestate and then dissociating this gaseous ammonia into nitrogen and hydrogen, said hydrogen being stored or used in a fuel cell. STATEMENT OF THE INVENTION

[0018] The invention aims precisely to provide a solution to these problems by proposing a process which makes it possible to synthesize a hydrogen-charged LOHC, noted H n -LOHC, using hydrogen produced from a methanization digestate.

[0019] This process comprises at least the steps of: a) production of gaseous ammonia from a methanization digestate; b) division of the gaseous ammonia produced in step a) into a first and a second stream; c) catalytic amination of a hydrogen-carrying organic liquid not charged with hydrogen, denoted H 0 -LOHC, by reaction with the gaseous ammonia of the first stream to convert the H 0 -LOHC into an aminated H 0 -LOHC and produce hydrogen; d) catalytic dissociation of the gaseous ammonia of the second stream to produce hydrogen; and e) catalytic hydrogenation of the aminated H 0 -LOHC obtained in step c), by reaction with the hydrogen produced in steps c) and d), whereby H n -LOHC is obtained.

[0020] Thus, according to the invention: gaseous ammonia (NH 3 ) is produced from a methanization digestate which is the residue of the anaerobic fermentation, or digestion, of organic waste (of agricultural, urban, industrial or other origin), part of the gaseous ammonia thus produced is used to aminate a non-hydrogen-charged LOHC, H 0 -LOHC, while the other part of the gaseous ammonia is used to produce hydrogen useful for the conversion of the aminated H 0 -LOHC into hydrogen-charged LOHC, H n -LOHC.

[0021] It goes without saying that steps c) and d) can be carried out simultaneously or successively, in which case they can be carried out in any order, i.e. step c) can be carried out after step d) as well as before step d).

[0022] According to the invention, the methanization digestate is preferably a liquid digestate, i.e. corresponding to the liquid phase obtained when a methanization digestate is subjected to a solid / liquid phase separation, for example by means of a screw press, a belt press, a filter press or a centrifuge.

[0023] In step a), gaseous ammonia is advantageously produced by desorption - also known by the English name stripping - ammoniacal nitrogen (i.e. the group formed by ammonia which is in molecular form NH 3 and that which is in ionized form NH a +< ) present in the liquid methanization digestate.

[0024] This desorption is preferably carried out by circulating the liquid digestate in a column provided with packing of the type Raschig rings, Pall rings, Berl saddles or the like, against the current of a gas called transfer gas which is either nitrogen or a gas essentially consisting of nitrogen such as air. The transfer gas may be preheated, for example to a temperature of 50°C-70°C, so as to promote the desorption of ammoniacal nitrogen.

[0025] Alternatively, desorption can also be carried out by vacuum extraction (this is then referred to as stripping at empty).

[0026] In any case, the process advantageously further comprises a purification of the gaseous ammonia produced which is carried out, for example, by means of a membrane filter.

[0027] According to the invention, H 0 -LOHC is typically an aromatic or heteroaromatic, monocyclic or polycyclic compound, optionally substituted by one or more alkyl, aryl, heteroaryl, arylalkyl or heteroarylalkyl groups, which preferably meets the following criteria: be able to ensure fully reversible hydrogen storage viacatalytic processes; have favorable thermal stability, thermodynamics, and hydrogenation / dehydrogenation kinetics; have a sufficiently low melting point, ideally below -30°C, to be liquid or semi-liquid at room temperature (25°C) and thus avoid the need for a solvent to make it liquid or semi-liquid; have a high boiling point, ideally above 300°C, to simplify the purification of the hydrogen that will be produced when the H n -LOHC resulting from its hydrogenation is subjected to dehydrogenation; be non-toxic, non-flammable, and non-explosive under ambient conditions of temperature (25°C) and pressure (100 kPa); be widely available and inexpensive;and be able to be transported under ambient temperature and pressure conditions using the infrastructure currently used for liquid and semi-liquid fuels (pipelines, tanker trucks, etc.).

[0028] This may include: toluene which gives, by hydrogenation, methylcyclohexane, 2-benzyltoluene or 4-benzyltoluene which give respectively, by hydrogenation, perhydro-2-benzyltoluene and perhydro-4-benzyltoluene, 2,3-dibenzyltoluene or 2,4-dibenzyltoluene which give respectively, by hydrogenation, perhydro-2,3-dibenzyltoluene and perhydro-2,4-dibenzyltoluene, naphthalene which gives, by hydrogenation, decalin, N-ethylcarbazole which gives, by hydrogenation, perhydro- N-ethylcarbazole, indole which gives, by hydrogenation, perhydroindole, 1-methylindole, 2-methylindole, 3-methylindole, 4-methylindole, 5-methylindole or 6-methylindole which give respectively, after hydrogenation, perhydro-1-methylindole, perhydro-2-methylindole, perhydro-3-methylindole, perhydro-4-methylindole, perhydro-5-methylindole and perhydro-6-methylindole, 1,2-dimethylindole, 2,3-dimethylindole or 2,5-dimethylindole which give respectively, after hydrogenation, perhydro-1,2-dimethylindole, perhydro-2,3-dimethylindole and perhydro-2,5-dimethylindole, dibenzofuran which gives, after hydrogenation, perhydrobenzofuran, phenazine which gives, after hydrogenation, perhydrophenazine, 2-(N-methylbenzyl)pyridine which gives, after hydrogenation, perhydro-2-(N-methylbenzyl)pyridine, or 4,4'-bipiperidine which gives, after hydrogenation, perhydro-4,4'-bipiperidine.

[0029] In step c), the catalytic amination of H 0 -LOHC leads to the formation of an amino H 0 -LOHC and hydrogen according to the reaction: H 0 -LOHC + NH 3 ⇄ H 0 -LOHC-NH 2 + H 2 which in the case, for example, of toluene becomes:

[0030] It should be noted that this amination reaction can result in the presence of several NH 2 groups on the same H 0 -LOHC molecule.

[0031] This amination is advantageously carried out in a reactor heated to a temperature which is preferably chosen according to the catalyst used but which is typically between 200°C and 800°C and, more specifically, between 350°C and 500°C and under a pressure which is typically between 0.1 MPa and 90 MPa and, more specifically, between 1.5 MPa and 11 MPa. The catalyst is, for example, a ceramic-metal composite, based on a metal oxide such as an oxide of zirconium, nickel, cobalt, aluminum, a rare earth (yttrium or cerium oxide for example), and one or more active metals chosen from nickel, copper, zinc, platinum group metals (ruthenium, rhodium, palladium, iridium and platinum), vanadium, titanium, aluminum, silicon and actinides (uranium and thorium in particular).

[0032] In order to increase the yield of H 0 -LOHC amination, it is possible to shift the chemical equilibrium of this reaction towards the formation of hydrogen by consuming part of the hydrogen generated by this amination, in which case the amination is carried out in the presence of an oxidizing gas such as oxygen, carbon monoxide, carbon dioxide, nitric oxide, nitrogen dioxide, hydrogen peroxide or air.

[0033] Advantageously, the process further comprises a purification of the hydrogen produced by the catalytic amination of H 0 -LOHC, which is carried out, for example, by means of a membrane filter.

[0034] In step d), the catalytic dissociation of gaseous ammonia leads to the formation of nitrogen and hydrogen according to the reaction: 2NH 3 → N 2 + 3H 2

[0035] This dissociation is advantageously carried out in a reactor heated to a temperature which is preferably chosen according to the catalyst used but which is typically between 450°C and 800°C and, more specifically, between 550°C and 700°C. The catalyst is, for example, a ceramic-metal composite comprising an active metal such as ruthenium, nickel or copper, and an oxide such as alumina, magnesia or even a rare earth oxide such as ceria.

[0036] Here too, the process advantageously further comprises a purification of the hydrogen produced by the catalytic dissociation of gaseous ammonia, which is carried out, for example, by means of a membrane filter.

[0037] Regardless of the amine H 0 -LOHC that is to be hydrogenated, its hydrogenation is typically carried out with a high hydrogen pressure, preferably between 5 MPa and 10 MPa. Since the reaction is exothermic and therefore releases heat, the reactor in which the hydrogenation is carried out typically reaches a temperature between 100°C and 200°C. These conditions can, of course, vary depending on the amine H 0 -LOHC and the catalyst used. The catalyst is, for example, a ceramic-metal composite comprising an active metal such as ruthenium, nickel or cobalt, and an oxide such as alumina, zirconia or a rare earth oxide such as ceria.

[0038] The hydrogen pressure is advantageously controlled in order to limit itself to the hydrogenation reaction without going as far as hydrogenolysis which would lead to the departure of the NH 2 group(s).

[0039] According to the invention, the reactor in which the catalytic dissociation of gaseous ammonia is carried out and, where appropriate, the reactor in which the catalytic amination of H 0 -LOHC is carried out are advantageously heated by the heat and / or electricity produced from a methanization biogas. The same is also advantageously true for the transfer gas used for the desorption of ammoniacal nitrogen if this transfer gas is previously heated.

[0040] Thus, the process for synthesizing an H n -LOHC as previously defined can advantageously be included in a process for recovering organic waste, which comprises at least the steps of: methanization of organic waste to produce methanization digestate and biogas; synthesis of H n -LOHC from the methanization digestate by implementing said synthesis process; and production of heat and / or electricity from the biogas.

[0041] The invention therefore also relates to such a process for recovering organic waste.

[0042] The invention also relates to a process for producing hydrogen, which comprises at least the steps of: synthesis of an H n -LOHC by implementing the method for synthesizing an H n -LOHC as previously defined; conditioning of the H n -LOHC for its storage and / or its transport; and catalytic dehydrogenation of the H n -LOHC thus conditioned.

[0043] As known per se: the conditioning of H n -LOHC can be carried out in the same type of tanks as those used to condition hydrocarbons, at room temperature and atmospheric pressure; while the catalytic dehydrogenation of H n -LOHC can be carried out in a reactor heated to a temperature which is preferably chosen according to the catalyst and H n -LOHC used but which is typically between 100 °C and 350 °C and, more specifically, between 150 °C and 300 °C. The reaction is typically carried out at atmospheric pressure. The catalyst is, for example, a ceramic-metal composite comprising a platinoid such as platinum or palladium, and an oxide such as alumina.

[0044] Other characteristics and advantages of the invention will appear on reading the additional description which follows and which is given with reference to the appended figures.

[0045] It goes without saying that this additional description is given only as an illustration of the subject of the invention and in no way constitutes a limitation of this subject. BRIEF DESCRIPTION OF THE FIGURES

[0046] There figure 1 schematically illustrates a preferred mode of implementation of the method for synthesizing an H n -LOHC according to the invention and of producing an installation designed for this mode of implementation. The figure 2 schematically illustrates a preferred mode of implementation of the organic waste recovery process according to the invention and of production of an installation designed for this mode of implementation. DETAILED DESCRIPTION OF A PREFERRED IMPLEMENTATION METHOD

[0047] We refer to the figure 1 which schematically represents a preferred mode of implementation of the method for synthesizing an H n -LOHC according to the invention and of producing an installation, referenced 10, designed for this mode of implementation.

[0048] In this mode of implementation, the method comprises: 1. the production of gaseous ammonia, NH 3 , by desorption (or stripping ) ammonia nitrogen from a liquid digestate; 2. purifying the gaseous ammonia thus produced and splitting it into a first and a second stream; 3. catalytic amination of an H 0 -LOHC using the gaseous ammonia of the first stream to convert this H 0 -LOHC into an amino H 0 -LOHC and produce hydrogen; 4. catalytic dissociation of the gaseous ammonia of the second stream to produce hydrogen; 5. purifying the hydrogen produced by the catalytic amination of the H 0 -LOHC and by the catalytic dissociation of ammonia; and 6. catalytic hydrogenation of the amino H 0 -LOHC using the hydrogen thus purified to convert this amino H 0 -LOHC into an amino H n -LOHC.

[0049] To do this and as visible on the figure 1, the installation 10 comprises a desorption column 11, which is filled with a packing 12 such as Raschig or Pall rings and in which the production of gaseous ammonia is carried out.

[0050] The liquid digestate, which is subjected to this desorption, comes from the separation into a solid phase and a liquid phase of a methanization digestate.

[0051] This liquid digestate mainly comprises nitrogen, including ammoniacal nitrogen, phosphorus in oxide form (P 2 O 5 ), potassium in oxide form (K 2 O), calcium in oxide form (CaO) and magnesium, also in oxide form (MgO), in varying concentrations depending on the organic waste from which the methanization digestate was obtained.

[0052] Column 11 is supplied: in the lead, by liquid digestate via a pump (not shown on the figure 1), and at the bottom, by a transfer gas which can be nitrogen or a gas essentially consisting of nitrogen such as air but which, in the case of the method of implementing the process illustrated on the figure 1 , is nitrogen, which is injected under pressure into column 11 from a nitrogen source 13.

[0053] The liquid digestate and nitrogen therefore circulate counter-currently in column 11.

[0054] The nitrogen may be heated prior to entering column 11, for example to a temperature of 50°C to 70°C, to promote the desorption of ammoniacal nitrogen.

[0055] At the top of column 11, a gaseous phase essentially formed of ammonia and nitrogen is recovered and, at the bottom of column 11, a liquid digestate depleted in ammoniacal nitrogen.

[0056] The gaseous phase thus recovered is directed towards a purification device 14, for example of the membrane filter type, making it possible to purify the ammonia by separating it from the nitrogen and any other gases generated by the desorption, while the digestate depleted in ammoniacal nitrogen is eliminated from the process by being, for example, directed towards a storage unit (not shown in the figure 1 ) for later spreading.

[0057] As visible on the figure 1 , the nitrogen leaving the purification device 14 can, after having itself undergone possible purification, be directed towards the nitrogen source 13 with a view to its reinjection into the column 11. As a variant, it can also be eliminated from the process for its reuse in other applications or, more simply, its release into the atmosphere.

[0058] As for the ammonia leaving the purification device 14, it is divided into two flows: a first flow which is directed towards a reactor 15 dedicated to the catalytic amination of H 0 -LOHC and which is, therefore, supplied with this H 0 -LOHC, and a second flow which is directed towards a reactor 16 dedicated to the catalytic dissociation of ammonia.

[0059] In reactor 15, the catalytic amination of H 0 -LOHC is, for example, carried out at a temperature between 350 °C and 500 °C and under a pressure between 1.5 MPa and 11 MPa, using a Ni / CeO 2 type catalyst.

[0060] As previously indicated, the efficiency of the catalytic amination of H 0 -LOHC can be increased by consuming a portion of the hydrogen generated by this amination, by supplying the reactor 15 with an oxidizing gas such as oxygen, carbon monoxide, carbon dioxide, nitrogen monoxide, nitrogen dioxide, hydrogen peroxide or air. In which case, the portion of the hydrogen generated by the catalytic amination of H 0 -LOHC which is not consumed in the reactor 15 is evacuated from this reactor through, for example, a membrane filter to separate it from the oxidizing gas.

[0061] Whether or not an oxidizing gas is used for the catalytic amination of H 0 -LOHC, the hydrogen leaving the reactor 15 is then directed to a purification device 18, for example of the membrane filter type, while the aminated H 0 -LOHC is directed to a reactor 17 dedicated to its hydrogenation.

[0062] At the same time, the catalytic dissociation of the gaseous ammonia from the second stream from the purification device 14 is carried out in the reactor 16. This dissociation is, for example, carried out at a temperature between 550°C and 700°C and using a Ni / MgO type catalyst.

[0063] The hydrogen produced in the reactor 16 is then directed to the purification device 18 where it joins the hydrogen having been evacuated from the reactor 15.

[0064] Once purified by the purification device 18, the hydrogen is directed to the reactor 17 to be used for the catalytic hydrogenation of the amine H 0 -LOHC.

[0065] This hydrogenation is, for example, carried out with a hydrogen pressure between 5 MPa and 10 MPa and using a Ru / Al 2 O 3 type catalyst.

[0066] The H n -LOHC amine produced in reactor 17 is then sent to an area dedicated to its conditioning (not shown in the figure 1 ) for its storage and / or transport.

[0067] We now refer to the figure 2 which schematically represents a preferred mode of implementation of the organic waste recovery process according to the invention as well as an installation, referenced 20, designed for this mode of implementation.

[0068] In this mode of implementation, the organic waste recovery process includes: 1. the methanization of organic waste to produce a methanization digestate on the one hand, and a biogas on the other hand; 2. the separation of the methanization digestate into a solid phase, called solid digestate, and a liquid phase, called liquid digestate; 3. the synthesis of an H n -LOHC from the liquid digestate by the process for synthesizing an H n -LOHC according to the invention; and 4. cogeneration, i.e. the simultaneous production of electricity and heat, from the biogas.

[0069] To do this and as visible on the figure 2, organic waste, which may in particular be agricultural waste such as cattle manure, pig slurry or cereal residues, urban waste such as household waste or sludge from wastewater treatment plants, industrial waste such as waste from the agri-food industry, or even a mixture of waste from different origins, are introduced into the methanizer, also called digester, of a methanization unit 21, in which they are subjected to anaerobic fermentation, typically at a temperature between 20°C and 60°C, which leads to the formation, on the one hand, of a pasty product which is given the name of methanization digestate and, on the other hand, of a biogas which is essentially made up of CH 4 and CO 2 .

[0070] The methanization digestate, once evacuated from the methanizer 21, is directed to a solid / liquid separation unit 22 in which it is separated into a solid digestate and a liquid digestate, for example by means of one or more devices of the screw press, belt press, filter press or centrifuge type.

[0071] The solid digestate thus obtained can be sent to a storage unit (not shown in the figure 2 ) for subsequent spreading and / or to a post-treatment unit (not shown on the figure 2 ) of the drying or composting unit type.

[0072] As for the liquid digestate, it is directed towards an installation 23 dedicated to the synthesis of H n -LOHC, which can in particular be an installation of the type shown in the figure 1 . The H n -LOHC thus synthesized is then directed to an area dedicated to its conditioning (not shown on the figure 2) for its storage and / or transport.

[0073] At the same time, the biogas produced in the methanizer 21 is directed towards a cogeneration unit 24 comprising, for example, a gas turbine coupled to an alternator and a heat recovery unit.

[0074] As illustrated in the figure 2 , the electricity and / or heat thus produced can in particular be used for the operation of: of the methanization unit 21 and, in particular, for heating the methanizer, the solid / liquid separation unit 22, and / or the installation 23 dedicated to the synthesis of H n -LOHC and, in particular, for heating the transfer gas used for the desorption of ammoniacal nitrogen if the gaseous ammonia is produced by desorption as well as for heating the reactors in which the catalytic dissociation of the gaseous ammonia and, where appropriate, the catalytic amination of H 0 -LOHC are carried out.

[0075] This achieves optimal recovery of organic waste. CITED REFERENCE

[0076] Purna Chandra Rao and Minyoung Yoon, Energies 2020, 13(22), 1-23

Claims

1. Synthesis process of a liquid organic hydrogen carrier charged with hydrogen, Hn-LOHC, comprising at least the steps of: a) production of gaseous ammonia from a methanisation digestate; b) division of the gaseous ammonia produced in step a) into a first and a second flow; c) catalytic amination of a liquid organic hydrogen carrier not charged with hydrogen, H0-LOHC, by reaction with the gaseous ammonia from the first flow to convert the H0-LOHC into an aminated H0-LOHC and produce hydrogen; d) catalytic dissociation of the gaseous ammonia from the second flow to produce hydrogen; and e) catalytic hydrogenation of the aminated H0-LOHC obtained in step c), by reaction with the hydrogen produced in steps c) and d), whereby the Hn-LOHC is obtained.

2. Process according to claim 1, wherein the methanisation digestate is a liquid digestate.

3. Process according to claim 2, wherein the production of gaseous ammonia comprises a desorption of the ammoniacal nitrogen contained in the liquid digestate in the form of gaseous ammonia.

4. Process according to claim 3, wherein the desorption comprises a circulation of the liquid digestate in a packing column, against a flow of nitrogen or a gas essentially consisting of nitrogen.

5. Process according to any one of claims 1 to 4, further comprising a purification of the gaseous ammonia produced.

6. Process according to any one of claims 1 to 5, wherein the catalytic dissociation of the gaseous ammonia is carried out in a reactor heated to a temperature between 450°C and 800°C.

7. Process according to any one of claims 1 to 6, further comprising a purification of the hydrogen produced by the catalytic dissociation of gaseous ammonia.

8. Process according to any one of claims 1 to 7, wherein the H0-LOHC is an aromatic or heteroaromatic, monocyclic or polycyclic, compound, optionally substituted by one or more alkyl, aryl, heteroaryl, arylalkyl or heteroarylalkyl groups.

9. Process according to claim 8, wherein the H0-LOHC is toluene, 2-benzyltoluene, 4-benzyltoluene, 2,3-dibenzyltoluene, 2,4-dibenzyltoluene, naphthalene, N-ethylcarbazole, indole, 1-methylindole, 2-methylindole, 3-methylindole, 4-methylindole, 5-methylindole, 6-methylindole, 1,2-dimethylindole, 2,3-dimethylindole, 2,5-dimethylindole, dibenzofuran, phenazine, 2-(N-methylbenzyl)pyridine or 4,4'-bipiperidine.

10. Process according to any one of claims 1 to 9, wherein the catalytic amination of the H0-LOHC is carried out in a reactor heated at a temperature between 200°C and 800°C and at a pressure between 0.1 MPa and 90 MPa.

11. Process according to any one of claims 1 to 10, further comprising a purification of the hydrogen produced by the catalytic amination of the H0-LOHC.

12. Process according to any one of claims 1 to 11, wherein the catalytic hydrogenation of the aminated H0-LOHC is carried out with a hydrogen pressure between 5 MPa and 10 MPa.

13. Process according to any one of claims 6 or 10, wherein the reactor is heated by heat and / or electricity produced from a methanisation biogas.

14. Process for recycling organic waste, comprising at least the steps of: - methanisation of the organic waste to produce a methanisation digestate and a biogas; - synthesis of a liquid organic hydrogen carrier charged with hydrogen, annotated Hn-LOHC, from the methanisation digestate by implementing a process according to any one of claims 1 to 13; and - production of heat and / or electricity from the biogas.

15. Process for producing hydrogen, comprising at least the steps of: - synthesis of a liquid organic hydrogen carrier charged with hydrogen, annotated Hn-LOHC, by implementing a process according to any one of claims 1 to 13; - packaging the Hn-LOHC for storage and / or transport; and - catalytic dehydrogenation of the Hn-LOHC thus packaged.