Coaxial electrolysis device

Abstract

An elongate coaxial electrolysis device (Figure 1, 1) for electrolysis of an electrolyte is described. The electrolysis device (Figure 1, 1) comprises at least one cell 2 with a concentric electrode a

Description

The present invention relates to an elongate coaxial electrolysis device for the production of green hydrogen. BACKGROUND OF INVENTION It is well known that the global demand for energy is steadily increasing and the current widely used fossil fuel resources have damaging effects on the environment. There is therefore a need to develop sustainable, non-carbon, non-fossil based, "green" energy sources for large scale use. Electrolysis is considered to provide a clean route for hydrogen generation from water without the consumption of fossil fuel or the emission of carbon dioxide (also known as "Green Hydrogen"). However, over 50% of the world does not have access to clean drinking water or water which is suitable for use with an electrolyser to create Green Hydrogen. While Green Hydrogen can be produced at zero emissions, the conventional production process is not cost efficient. The current equipment is sub-scale and operating at substantially high costs. Electrolysis of water to generate hydrogen fuel could be vital to the future renewable energy landscape. However, the amount of hydrogen needed to power cities and cars is significant and this cannot be achieved using purified water due to the lack of availability globally. There is a need for an electrolysis device which is capable of producing hydrogen using alternative water sources. SUMMARY OF INVENTION According to a first aspect of the present invention, there is provided an elongate coaxial electrolysis device for electrolysis of an electrolyte, the electrolysis device comprising at least one cell comprising: a concentric electrode arrangement comprising: a continuous inner elongate electrode providing at least one opening, slot or perforation, or any combination thereof; and an outer elongate electrode, in which the inner and outer elongate electrodes define a longitudinal axis. The electrolysis device is preferably membrane-less (i.e. does not contain a membrane or filter). The electrolysis device is preferably operable without the use of a pump. The longitudinal axis preferably extends between a first end and an opposed second end of the continuous inner elongate electrode. The elongate coaxial electrolysis device may comprise a single outer electrode, for example a single outer elongate electrode. The elongate coaxial electrolysis device may be a tubular coaxial electrolysis device. The inner elongate electrode may be an inner tubular electrode. The outer elongate electrode may be an outer tubular electrode. In one embodiment, the outer electrode is non-contiguous and comprises a plurality of discrete outer electrodes. The device may comprise any suitable number of outer electrodes. For example, the device preferably comprises three outer electrodes. The outer elongate electrode may have any suitable shape and / or dimensions. Each outer elongate electrode is preferably ring-shaped. Each outer elongate electrode preferably extends substantially around the periphery of the inner elongate electrode. The outer electrodes may be spaced apart from each other along the longitudinal axis of the electrodes (for example inner elongate electrode(s)). In one embodiment, the discrete outer electrodes are preferably evenly spaced apart from each other along the length of the inner elongate electrode. The spacing between each pair of adjacent discrete outer electrodes may vary. It is to be understood that the spacing between each pair of adjacent discrete outer electrodes may be any suitable spacing. In one embodiment, the spacing between a pair of adjacent outer electrodes is approximately 1 cm. The single continuous inner elongate electrode preferably comprises a plurality of openings, slots or perforations, or any combination thereof. The plurality of openings, slots or perforations are preferably spaced apart from each other along the length of the electrode (for example along the longitudinal axis). The inner and outer electrodes may be composed of any suitable material. In one embodiment, at least one (preferably each) of the inner and / or outer electrodes are composed of stainless steel or biochar. The stainless steel is preferably recycled stainless steel. As such, the electrolysis device of the present invention is environmentally friendly by being formed from waste products or recycled materials. In one embodiment, the inner and / or outer electrode is composed of 3D printed biochar. The biochar is preferably formed from one or more of: soft plant tissue, woody material and / or manure, or any combination thereof. The electrodes of the present invention have been found to be capable of withstanding corrosion when used with seawater. The continuous inner electrode preferably comprises a first end and a second opposed end, and in which an attachment feature is provided at at least one of the first and / or second ends. The attachment feature is preferably configured for releasable engagement to a further continuous inner electrode. The attachment feature may for example comprise a threaded portion. In one embodiment, a first end of the inner electrode comprises a male attachment feature comprising a threaded portion, and in which the second end of the inner electrode comprises a female attachment feature comprising a threaded portion. The threaded portion of the male attachment feature is configured for releasable threaded engagement with the cooperative threaded portion of a female attachment feature provided at a second end of a further inner electrode. The electrolysis device may comprise a single continuous inner electrode with a plurality of spaced apart outer electrode mounted thereon along the length of the inner electrode. In one embodiment, the outer electrode is permanently attached to the continuous inner electrode. The outer electrode is preferably attached by welding to the continuous inner electrode. The coaxial electrolysis device may comprise a plurality of cells. The plurality of cells may be aligned along the longitudinal axis of the inner and outer electrodes. The device preferably further comprises an aqueous electrolyte. In one embodiment, the device further comprises a non-toxic electrolyte. The electrolyte preferably comprises biodegradable components. The electrolyte preferably comprises B-ionic electrolyte. The electrolyte preferably comprises grey water. In one embodiment, the electrolyte comprises 90% w / w grey water and optionally 10% w / w at least one salt and / or sugar. Examples of suitable salts and / or sugars (and / or derivatives) include citric acid and / or sorbitol. The grey water may comprise rainwater, flood water, runoff water, estuaries, or any combination thereof. Grey water such as rainwater can carry bacteria, parasites, viruses, and chemicals. It has been found that the presence of bacteria within the aqueous electrolyte (for example as a result of being present within the greywater, such as rainwater, enhances the performance of the electrolyte. The electrolyte may comprise one or more pathogens present within grey water selected from one or more of: Pathogens found in rainwater include members of genus Campylobacter spp., Salmonella spp., Shigella spp., Vibrio spp., pathogenic E. coli, Acinetobacter spp., Aeromonas spp., Citrobacter spp., Klebsiella spp., Legionella spp., Mycobacterium spp., Pseudomonas spp., Staphylococcus spp., Yersinia spp., Cryptosporidium spp., Giardia spp., Isospora spp., adenoviruses, Acanthamoeba spp., Naegleria spp., Entamoeba spp., or Endolimax spp, or any mixture thereof. In one embodiment, the coaxial electrolysis device further comprises a housing defining a cavity for receiving the at least one cell therein. The housing preferably comprises recycled materials, for example recycled plastic. In one embodiment, the housing comprises an inlet configured in use to be in communication with a source of electrolyte and to provide electrolyte to the cavity defined therein, and an outlet configured to allow electrolyte to be removed from the cavity of the housing. Preferably, the housing is configured to allow an electrolyte to flow therethrough. The devices may be used in combination. For example, the devices may be used in parallel or in series. For example, the electrolyte may flow through a plurality of devices arranged in parallel. Alternatively, the electrolyte may flow through a first device and subsequently pass through a second device (and optionally further devices) positioned in series. According to a second aspect of the present invention , there if provided a method for the separation of gases from an electrolyte comprising using a coaxial electrolysis device as herein described. Preferably, the generation of gases, for example hydrogen and oxygen from an aqueous electrolyte using a coaxial electrolysis device as herein described. In one embodiment, the electrolyte is present at a temperature of at least room temperature. The electrolyte may for example by heated to a temperature of at least 30 °C, preferably at least 40 °C, for example about 60 °C. The electrolyte is preferably heated to a temperature of no more than 80 °C, preferably no more than 70 °C. The device may allow for the generation of hydrogen gas from an aqueous electrolyte at a rate of at least 1000 L / hr, preferably at least 5000 L / hr, for example about 10000 L / hr. The device may allow for the generation of oxygen gas from an aqueous electrolyte at a rate of at least 500 L / hr, preferably at least 2000 L / hr, for example about 5000 L / hr. The device is preferably operated at a voltage of ~ 4V. The hydrogen gas produced preferably has a purity of at least 90%, preferably at least 95%, for example at least 98%. Embodiments of the present invention will now be described in further detail in relation to the accompanying Figures BRIEF DESCRIPTION OF FIGURES Figure 1 is a schematic exploded view of an elongate coaxial electrolysis device according to one embodiment of the present invention; Figure 2 is a photograph of an elongate coaxial electrolysis device according to a further embodiment of the present invention; Figure 3 is a photograph of an elongate coaxial electrolysis device according to a further embodiment of the present invention; Figure 4 is a schematic illustration of an outer electrode of the electrolysis device according to one embodiment of the present invention; and Figure 5 is a schematic illustration of an inner electrode of the electrolysis device according to one embodiment of the present invention. DETAILED DESCRIPTION With reference to the Figures, the elongate coaxial electrolysis device 1 for electrolysis of an electrolyte comprises a cell 2 comprises a concentric electrode arrangement. The device 1 is a tubular coaxial electrolysis device. The concentric electrode arrangement comprises a continuous inner tubular electrode 4 providing a plurality of openings (not shown); and an outer tubular electrode 6. The inner 4 and outer 6 tubular electrodes define a longitudinal axis. The electrolysis device is preferably membrane-less (i.e. does not contain a membrane or filter). The electrolysis device is preferably operable without the use of a pump. The cell 2 comprises a single outer tubular electrode 6. The device may comprise any suitable number of cells 2. For example. The device may comprise a plurality of stacked cells 2 providing a plurality of discrete outer tubular electrodes 6 spaced apart from each other along the length of the inner tubular electrode 4. The device may comprise any suitable number of cells 2 and outer tubular electrodes 6. As shown in Figure 1, the device 1 comprises six outer tubular electrodes 6. For example, the device preferably comprises three outer tubular electrodes. In Figure 2, the device 1 comprises four outer tubular electrodes 6. In Figure 3, the device 1 comprises two outer tubular electrodes 6. Each outer electrode 6 extends around the entire periphery of a portion of the inner tubular electrode 4 and spaced apart therefrom. As show in the Figures, each outer electrode 6 is substantially ring shaped. In the illustrated embodiments, the outer electrode 6 is permanently attached to the continuous inner tubular electrode 4 by welding to the continuous inner tubular electrode 4. In one embodiment, the discrete outer tubular electrodes 6 of the device 1 are evenly spaced apart from each other along the length of the inner tubular electrode 4. The spacing between each pair of adjacent discrete outer tubular electrodes may vary. It is to be understood that the spacing between each pair of adjacent discrete outer tubular electrodes may be any suitable spacing. In one embodiment, the spacing between a pair of adjacent outer tubular electrodes is approximately 1 cm. The single continuous inner tubular electrode 4 comprises a plurality of openings spaced apart from each other along the length of the electrode. The inner 4 and outer 6 tubular electrodes may be composed of any suitable material. In the illustrated embodiment, the inner 4 and outer electrodes 6 are composed of recycled stainless steel. It is however to be understood that the inner and / or outer tubular electrodes may be composed of stainless steel or biochar. As shown in Figure 5, the continuous inner tubular electrode 4 comprises a first end 8 and a second opposed end (not shown). An attachment feature 10 is provided at each of the first 8 and second ends. The attachment feature 10 is configured for releasable engagement to a further continuous inner tubular electrode (not shown) positioned in a stacked arrangement aligned along the longitudinal axis. In the illustrated embodiment, the attachment feature 10 comprises a female threaded portion. It is however to be understood that the attachment feature may be any suitable feature for engaging a first inner tubular electrode to an adjacent inner tubular electrode. For example, the attachment feature may be a female or male connector, for example push fit connector, for engaging a corresponding feature on an adjacent inner tubular electrode. The device 1 further comprises an aqueous electrolyte. The aqueous electrolyte is preferably a nontoxic electrolyte. In one embodiment, the electrolyte comprises biodegradable components. The electrolyte may comprise B-ionic electrolyte. The electrolyte may comprise grey water. In one embodiment, the electrolyte comprises 90% w / w grey water and optionally 10% w / w at least one salt and / or sugar. The grey water may comprise rainwater, flood water, runoff water, estuaries, or any combination thereof. Grey water such as rainwater can carry bacteria, parasites, viruses, and chemicals. It has been found that the presence of bacteria within the aqueous electrolyte (for example as a result of being present within the greywater, such as rainwater, enhances the performance of the electrolyte. The electrolyte may comprise one or more pathogens present within grey water selected from one or more of: Pathogens found in rainwater include members of genus Campylobacter spp., Salmonella spp., Shigella spp., Vibrio spp., pathogenic E. coli, Acinetobacter spp., Aeromonas spp., Citrobacter spp., Klebsiella spp., Legionella spp., Mycobacterium spp., Pseudomonas spp., Staphylococcus spp., Yersinia spp., Cryptosporidium spp., Giardia spp., Isospora spp., adenoviruses, Acanthamoeba spp., Naegleria spp., Entamoeba spp., or Endolimax spp, or any mixture thereof. The tubular coaxial electrolysis device 1 further comprises a housing 12 defining a cavity for receiving the stacked cells 2 therein. The housing 12 preferably comprises recycled materials, for example recycled plastic. The housing 12 comprises an inlet 14 configured in use to be in communication with a source of electrolyte and to provide electrolyte to the cavity defined therein, and an outlet 16 configured to allow electrolyte to be removed from the cavity of the housing 12. In use, the device 1 may be used to separate gases from an aqueous electrolyte. For example, a power supply is operated to enable electrolysis of the aqueous electrolyte within the cavity to generate gases, such as for example hydrogen and oxygen, from an aqueous electrolyte using the tubular coaxial electrolysis device as herein described. The device of the present invention allows for scaleable production of hydrogen from greywater with low associated operating costs and carbon footprint. The provision of the concentric electrodes enables the device to provide the high activation energy required in order to produce gases, such as hydrogen from the electrolyte. Example 1-Tubular Coaxial Electrolysis Device The operating parameters of the device according to one embodiment of the present invention are shown in Table 1: Specification Value Litres per hour of Hydrogen 10,000 1 Quality of Hydrogen 98% to 99% Voltage 4V Electrolyte temperature 60 °C Litres per hour of Oxygen 5,000 1 Quality of Oxygen gas 98% to 99% Table 1 The device can be provided in various sizes and the cells may be stacked together within the device to provide up to 100 MW of energy from green hydrogen production. Dimensions of a tubular coaxial electrolysis device for providing 50kW of energy from green hydrogen production are shown in Table 2: Diameter 710mm 0.71m Height 1815mm 1.815m Table 2 Dimensions of a tubular coaxial electrolysis device for providing 50kW of energy from green hydrogen production are shown in Table 3: Component Weight for 1 Stack (50kW) Weight for Functional Unit Interconnected 0.09 kg 3.62 E-04 kg Cathode 17.77 kg 7.27 E-02 kg Anode 125.08 kg 5.12 E-01 kg Frame 101.42 kg 4.15 E-01 kg Electrolyte (Weight of solid part) 1.99 E-03 kg 8.18E-06 kg Total Weight 244.36 kg 1 kg Table 3

Claims

1. An elongate coaxial electrolysis device for electrolysis of an electrolyte, the electrolysis device comprising at least one cell comprising:a concentric electrode arrangement comprising:a continuous inner elongate electrode providing at least one opening, slot or perforation, or any combination thereof; andan outer elongate electrode,the inner and outer elongate electrodes defining a longitudinal axis.

2. An elongate coaxial electrolysis device as claimed in claim 1, in which the device is free of a membrane or filter.

3. An elongate coaxial electrolysis device as claimed in either of claims 1 and 2, in which the outer elongate electrode is non-contiguous and comprises a plurality of discrete electrodes.

4. An elongate coaxial electrolysis device as claimed in claim 3, in which the device comprises three outer elongate electrodes.

5. An elongate coaxial electrolysis device as claimed in either of claims 3 and 4, in which each outer electrode extends substantially around the inner elongate electrode, and in which the outer electrodes are spaced apart from each other along the longitudinal axis of the inner electrodes.

6. An elongate coaxial electrolysis device a claimed in claim 5, in which the spacing between adjacent outer electrodes is approximately 1 cm.

7. An elongate coaxial electrolysis device as claimed in any one of claims 1 to 6, in which the single continuous inner elongate electrode comprises a plurality of openings, slots or perforations, or any combination thereof, and in which the plurality of openings, slots or perforations are spaced apart from each other along the length of the electrode.

8. An elongate coaxial electrolysis device as claimed in any one of claims 1 to 7, in which at least one electrode is composed of stainless steel or biochar.

9. An elongate coaxial electrolysis device as claimed in claim 8, in which the electrode is composed of 3D printed biochar.

10. An elongatecoaxial electrolysis device as claimed in either of claims 8 and 9, in which the electrode is composed of biochar formed from one or more of: soft plant tissue, woody material and / or manure.

11. An elongate coaxial electrolysis device as claimed in any preceding claim, in which the continuous inner elongate electrode comprises a first end and a second opposed end, and in which an attachment feature is provided at at least one of the first and / or second ends, in which the attachment feature is configured for releasable engagement to a further continuous inner elongate electrode.

12. An elongate coaxial electrolysis device as claimed in claim 11, in which the attachment feature comprises a threaded portion.

13. An elongate coaxial electrolysis device as claimed in any preceding claim, in which the outer electrode is permanently attached to the continuous inner elongate electrode.

14. An elongate coaxial electrolysis device as claimed in claim 13, in which the outer electrode is attached by welding to the continuous inner elongate electrode.

15. An elongate coaxial electrolysis device as claimed in any preceding claim, comprising a plurality of cells.

16. An elongate coaxial electrolysis device as claim in claim 15, in which the plurality of cells are aligned along the longitudinal axis of the inner and outer electrodes.

17. An elongate coaxial electrolysis device as claimed in any preceding claim, further comprising a non-toxic electrolyte.

18. An elongate coaxial electrolysis device as claimed in claim 17, in which the electrolyte comprises biodegradable components.

19. An elongate coaxial electrolysis device as claimed in either of claims 17 and 18, in which the electrolyte comprises B-ionic electrolyte.

20. An elongate coaxial electrolysis device as claimed in claim 19, in which the electrolyte comprises grey water.

21. An elongate coaxial electrolysis device as claimed in claim 20, in which the electrolyte comprises 90% w / w of grey water and 10% w / w of at least one salt and / or sugar.

22. An elongate coaxial electrolysis device as claimed in any preceding claim, further comprises a housing defining a cavity for receiving the at least one cell therein.

23. An elongate coaxial electrolysis device as claimed in any preceding claim, configured to allow an electrolyte to flow therethrough.

24. A method for the separation of gases from an electrolyte comprising using an elongate coaxial electrolysis device as claimed in any preceding claim.

25. A method for the generation of hydrogen and oxygen from an aqueous electrolyte using n elongate coaxial electrolysis device as claimed in any preceding claim.AMENDMENTS TO THE CLAIMS HAVE BEEN FILED AS FOLLOWS:CLAIMS1. An elongate coaxial electrolysis device for electrolysis of an electrolyte, the electrolysis device comprising at least one cell comprising:5 a concentric electrode arrangement comprising:a single continuous inner elongate electrode comprising a plurality of openings, slots or perforations, or any combination thereof, and in which the plurality of openings, slots or perforations are spaced apart from each other along the length of the electrode; and10 an outer elongate electrode,the inner and outer elongate electrodes defining a longitudinal axis;wherein, the outer elongate electrode is non-contiguous and comprises three, four, five or sixdiscrete electrodes.2.An elongate coaxial electrolysis device as claimed in claim 1, in which the device is free of amembrane or filter.

3. An elongate coaxial electrolysis device as claimed in claim 1 or claim 2, in which the devicecomprises three outer elongate electrodes.

4. An elongate coaxial electrolysis device as claimed in any one of claims 1 to 3, in which eachouter electrode extends substantially around the inner elongate electrode, and in which the20 outer electrodes are spaced apart from each other along the longitudinal axis of the innerelectrodes.

5. An elongate coaxial electrolysis device a claimed in claim 4, in which the spacing between adjacent outer electrodes is approximately 1 cm.

6. An elongate coaxial electrolysis device as claimed in any one of claims 1 to 5, in which at least25 one electrode is composed of stainless steel or biochar.

7. An elongate coaxial electrolysis device as claimed in claim 6, in which the electrode iscomposed of 3D printed biochar.

8. An elongate coaxial electrolysis device as claimed in either of claims 6 or 7, in which the electrode is composed of biochar formed from one or more of: soft plant tissue, woody material and / or manure.

9. An elongate coaxial electrolysis device as claimed in any preceding claim, in which the 5 continuous inner elongate electrode comprises a first end and a second opposed end, and inwhich an attachment feature is provided at at least one of the first and / or second ends, in which the attachment feature is configured for releasable engagement to a further continuous inner elongate electrode.

10. An elongate coaxial electrolysis device as claimed in claim 9, in which the attachment feature 10 comprises a threaded portion.

11. An elongate coaxial electrolysis device as claimed in any preceding claim, in which the outer electrode is permanently attached to the continuous inner elongate electrode.

12. An elongate coaxial electrolysis device as claimed in claim 11, in which the outer electrode is attached by welding to the continuous inner elongate electrode.15 13. An elongate coaxial electrolysis device as claimed in any preceding claim, comprising aplurality of cells.

14. An elongate coaxial electrolysis device as claim in claim 13, in which the plurality of cells are aligned along the longitudinal axis of the inner and outer electrodes.

15. An elongate coaxial electrolysis device as claimed in any preceding claim, further comprising 20 a non-toxic electrolyte.

16. An elongate coaxial electrolysis device as claimed in claim 15, in which the electrolyte comprises biodegradable components.

17. An elongate coaxial electrolysis device as claimed in either of claims 15 and 16, in which the electrolyte comprises B-ionic electrolyte.25 18. An elongate coaxial electrolysis device as claimed in claim 17, in which the electrolytecomprises grey water.

19. An elongate coaxial electrolysis device as claimed in claim 18, in which the electrolyte comprises 90% w / w of grey water and 10% w / w of at least one salt and / or sugar.CM 1— CM20. An elongate coaxial electrolysis device as claimed in any preceding claim, further comprising a housing defining a cavity for receiving the at least one cell therein.

21. An elongate coaxial electrolysis device as claimed in any preceding claim, configured to allow an electrolyte to flow therethrough.5 22. A method for the separation of gases from an electrolyte comprising using an elongate coaxialelectrolysis device as claimed in any preceding claim.

23. A method for the generation of hydrogen and oxygen from an aqueous electrolyte using n elongate coaxial electrolysis device as claimed in any preceding claim.Application No: GB2315442.0Claims searched: 1-25Examiner: Dr Marian LillingtonDate of search: 4 April 2024Patents Act 1977: Search Report under Section 17Documents considered to be relevant:Category Relevant to claims Identity of document and passage or figure of particular relevance X 1-7,13,15- GB1242469 A 18,22-25 (GEN ELECTRIC) Figures, pages 1-4 X 1,2,7,8,11 US 2015 / 0114832 Al ,12,15,17-25 (NICOLSON) Figures 1-6, paragraphs [0037]-[0060] and examples X 1,2,7,11,1 US4379043 A 2,15,17,1 8,20,22- 25 (CHAPPELLE) Figures 1-8, columns 3-6 X 1,2,7,8,11 US4039422 A ,13,15,22-24 (PACKER) Figures 1-5, columns 2-7 X 1,2,7,13,1 US2643223 A 4,15,22,2 3,24 (NOTVEST) Figures 1-5, columns 1-6 A Sustainable Printed Electrochemical Platforms for Greener Analytics, Sfragano et al, Front. Chern., 30 July 2020, Volume 8Categories:X Document indicating lack of novelty or inventive step A Document indicating technological background and / or state of the art. Y Document indicating lack of inventive step if P Document published on or after the declared priority date but combined with one or more other documents of same category. before the filing date of this invention. & Member of the same patent family E Patent document published on or after, but with priority date earlier than, the filing date of this application.Field of Search:International Classification:Subclass Subgroup Valid From C25B 0001 / 04 01 / 01 / 2021 C25B 0009 / 17 01 / 01 / 2021 C25B 0011 / 02 01 / 01 / 2021 C25B 0011 / 03 01 / 01 / 2021

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