CN113387427A - Diaphragm cathode and microbial electrolysis cell - Google Patents
Diaphragm cathode and microbial electrolysis cell Download PDFInfo
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- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
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- C25B1/00—Electrolytic production of inorganic compounds or non-metals
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- C25B—ELECTROLYTIC OR ELECTROPHORETIC PROCESSES FOR THE PRODUCTION OF COMPOUNDS OR NON-METALS; APPARATUS THEREFOR
- C25B13/00—Diaphragms; Spacing elements
- C25B13/02—Diaphragms; Spacing elements characterised by shape or form
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- C25B9/00—Cells or assemblies of cells; Constructional parts of cells; Assemblies of constructional parts, e.g. electrode-diaphragm assemblies; Process-related cell features
- C25B9/17—Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof
- C25B9/19—Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof with diaphragms
- C25B9/21—Cells comprising dimensionally-stable non-movable electrodes; Assemblies of constructional parts thereof with diaphragms two or more diaphragms
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- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
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Abstract
The invention discloses a diaphragm cathode, which comprises a porous hydrophilic film, a cathode and a porous hydrophobic film which are sequentially packaged. The invention also discloses a microbial electrolysis cell comprising the diaphragm cathode. The diaphragm cathode provided by the invention adopts the porous hydrophilic membrane and the porous hydrophobic membrane which are low in price, so that the distance between the diaphragm and the cathode is reduced, the internal resistance of the microbial electrolytic cell is effectively reduced, the current density and the hydrogen production rate are improved, and meanwhile, the diffusion of hydrogen to an anode chamber is prevented.
Description
Technical Field
The invention relates to the technical field of biological wastewater treatment. More particularly, the invention relates to a diaphragm cathode and a microbial electrolysis cell.
Background
Energy and resource recovery has become the best practice in the wastewater treatment industry. Microbial fuel cells, which provide a direct means of converting biodegradable organic matter into electrical energy, have been rapidly developed in recent years. The microbial electrolysis cell is a hydrogen production device improved on the basis of MFC, and in the technology of producing hydrogen through wastewater treatment, the performance of the microbial electrolysis cell is superior to that of a fermentation or photobiological process. The anode of the microbial electrolysis cell converts the biodegradable substrate into electrons by using electrogenic microorganisms and then transfers the electrons to the cathode and H+Hydrogen is produced, and the process only needs an external voltage of 0.2-1.0V. The generated hydrogen energy is derived from chemical energy stored in the substrate, and thus the microbial electrolysis cell can generate more energy than the inputted external energy. However, methane production remains a serious challenge for all microbial electrolysis cells, directly affecting hydrogen production. Much research into the inhibition of MEC methanogenesis has been extensively focused on, including chemical inhibitors, exposure to O2Reduced hydraulic retention time, low pH operation, temperature control, carbonate limitation, uv irradiation, and the like. Most of them have found limited success, and many suffer from other problems such as inhibition of growth of the electrogenic bacteria, environmental unfriendliness, high cost and short-term success. Furthermore, these strategies only suppress methanogenesis, but ignore the pathways responsible for hydrogen recycle. Part of the anode electrogenesis bacteria can also directly oxidize hydrogen as an electron donor, and can also convert the hydrogen into acetic acid by utilizing the homoacetogenesis process. Both of these pathways result in the regeneration of the current and then the production of hydrogen at the cathode, referred to as hydrogen recycle. While hydrogen circulation between the anode and cathode may not result in significant hydrogen loss, it increases anode and cathode overpotential loss and operating cycle time, resulting in lower hydrogen recovery. For these reasons, rapid separation of hydrogen from the MEC reactor is critical to reduce hydrogen diffusion to the anode and suppress methane formation.
Disclosure of Invention
An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.
The invention also aims to provide a diaphragm cathode and a microbial electrolytic cell, wherein the diaphragm cathode adopts a porous hydrophilic membrane and a porous hydrophobic membrane which are low in price, the distance between the diaphragm and the cathode is reduced, the internal resistance of the microbial electrolytic cell is effectively reduced, the current density and the hydrogen production rate are improved, and the diffusion of hydrogen to an anode chamber is prevented.
To achieve these objects and other advantages in accordance with the present invention, a separator cathode is provided, comprising a porous hydrophilic membrane, a cathode, and a porous hydrophobic membrane, which are sequentially encapsulated.
Preferably, the porous hydrophilic membrane and the porous hydrophobic membrane are tightly attached to two sides of the cathode without intervals to realize encapsulation.
Preferably, the cathode is a titanium mesh, a nickel mesh or a carbon cloth, and is loaded with trace Pt/C (1-5 mg-cm)-2) As a hydrogen evolution catalyst.
Microbial electrolysis cell, including no interval encapsulation in proper order anode chamber diaphragm cathode, air chamber, power, the diaphragm cathode with anode chamber, air chamber pass through the sealing member encapsulation, the anode chamber has inlet, gas outlet and inside and is equipped with the positive pole, the anode chamber is the liquid chamber, the anode chamber is anaerobic environment, the air chamber has the gas outlet, the cathode with the positive pole establishes ties through external circuit the power.
Preferably, the anode is a carbon brush or a carbon felt as a substrate on which an electrogenic microbial film grows, and the cathode is a titanium net, a nickel net or a carbon cloth and is loaded with trace Pt/C (1-5 mg-cm)-2) As a hydrogen evolution catalyst.
Preferably, the applied voltage is 0.5-1.2V, pH is 7, and the temperature is 25-30 ℃.
The method for producing hydrogen by using the microbial electrolytic cell comprises the following steps: the microbial electrolytic cell takes 1-5g/L organic matter as a substrate, and necessary nutrient salt is added at the same time,the anode adopts carbon brush or carbon felt as substrate, electrogenesis microbial film grows on the anode, and the cathode adopts titanium net, nickel net or carbon cloth loaded with micro Pt/C (1-5mg cm)-2) As a hydrogen evolution catalyst, the whole reaction is carried out at the temperature of 25-30 ℃, the pH is 7, the applied voltage is 0.5-1.2V, the generated gas is collected by a gas bag, the organic matters comprise acetate, easily degradable organic matters and/or domestic sewage, and the nutritive salts comprise nitrogen sources, phosphorus sources, mineral salts and/or trace elements.
The invention at least comprises the following beneficial effects:
firstly, the diaphragm cathode provided by the invention adopts the porous hydrophilic membrane and the porous hydrophobic membrane which are low in price, the structure of the diaphragm cathode reduces the distance between the diaphragm and the cathode, the pH balance is kept, the hydrogen methanation is effectively inhibited, the hydrogen yield is improved, compared with a proton exchange membrane, the diaphragm cathode can avoid the voltage loss caused by pH splitting, the price is low, the application is favorably expanded, and the membrane resistance is small;
and secondly, when the diaphragm cathode is applied to a microbial electrolytic cell, the distance between the diaphragm and the cathode is reduced, the total internal resistance of the microbial electrolytic cell is reduced, the design of the air chamber accelerates the hydrogen generated by the cathode to diffuse to the air chamber for collection, the cathode recovery efficiency is improved, the stay of the hydrogen in the solution is reduced, the current regeneration caused by the circulation of the hydrogen in the solution is favorably prevented, the hydrogen is prevented from being captured by methanotrophic bacteria to generate methane, and the hydrogen yield is improved.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.
Drawings
FIG. 1 is an exploded view of a microbial cell according to one embodiment of the present invention;
FIG. 2 is a schematic structural view of a microbial electrolytic cell according to an embodiment of the present invention;
fig. 3 is a current density plot of a single chamber MEC and a membrane cathode MEC of the present invention;
fig. 4 is a gas composition diagram of a GC test of a single-cell MEC and a membrane cathode MEC of the present invention.
Detailed Description
The present invention is further described in detail below with reference to the attached drawings so that those skilled in the art can implement the invention by referring to the description text.
It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.
It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials, if not otherwise specified, are commercially available; in the description of the present invention, it should be noted that unless otherwise explicitly stated or limited, the terms "mounted," "connected," and "disposed" are to be construed broadly and can, for example, be fixedly connected, disposed, detachably connected, disposed, or integrally connected and disposed. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art. The terms "lateral," "longitudinal," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," and the like are used in the orientation or positional relationship indicated in the drawings for convenience in describing the invention and to simplify the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus should not be construed as limiting the invention.
The diaphragm cathode comprises a porous hydrophilic film, a cathode and a porous hydrophobic film which are sequentially packaged. Compared with the traditional proton exchange membrane, the diaphragm cathode can avoid voltage loss caused by pH splitting, is low in price and beneficial to expanding application, and has small membrane resistance. The porous hydrophilic film and the porous hydrophobic film can be attached to or arranged at intervals of the cathode, and the cathode is a titanium net, a nickel net or carbon cloth as long as the periphery is packaged. The diaphragm cathode can be theoretically applied to a membrane bioreactor, a microbial fuel cell, a microbial electrolysis cell and the like.
In another technical scheme, the porous hydrophilic membrane and the porous hydrophobic membrane are tightly attached to two sides of the cathode without intervals to realize encapsulation. The cathode is prevented from being completely immersed in the solution, and the pollution of pollutants in the solution to the cathode is reduced. The method is favorable for reducing the stay of hydrogen generated by the cathode in the solution and reducing the distance between the membrane and the cathode, thereby reducing the ohmic loss caused by the distance.
The microbial electrolysis cell comprises an anode chamber, a diaphragm cathode, an air chamber and a power supply which are sequentially packaged without intervals, wherein a pair of silica gel pads are respectively arranged between the porous hydrophilic membrane and the anode chamber, between the porous hydrophobic membrane and the air chamber, and are used for sealing the microbial electrolysis cell. The anode chamber has inlet, gas outlet and inside is equipped with the positive pole, the anode chamber is the liquid chamber, the anode chamber is anaerobic environment, the air chamber has the gas outlet, the negative pole with the positive pole passes through the external circuit series connection the power, the external circuit can establish ties 10 omega resistance. The method can take domestic sewage, fermentation waste liquid, garbage leachate, activated sludge, organic acid, cellulose and other organic wastes as substrates (the appropriate pretreatment such as acid-base pretreatment, chemical oxidation pretreatment, thermal pretreatment, mechanical pretreatment and the like can effectively destroy microbial cell walls in the organic wastes and release intracellular organic matters), the mixed bacteria for the microbial electrolytic cell and the fuel cell enrich electrogenic bacteria at an anode through domestication, in the microbial electrolytic cell, the organic matters are decomposed under the action of the electrogenic bacteria in an anode chamber under the anaerobic environment, electrons and protons are released, the electrons are effectively transferred between microbial components and the anode by virtue of an appropriate electron transfer mediator and are transferred to a cathode through an external circuit, and the protons are transferred to the cathode through a diaphragm cathode, receive the electrons on the cathode to generate hydrogen and enter a gas chamber.
The anode is a carbon brush or a carbon felt as a substrate on which an electrogenesis microbial film grows, and the cathode is a titanium net, a nickel net or a carbon cloth and is loaded with trace Pt/C (1-5 mg-cm)-2) As a hydrogen evolution catalyst.
The applied voltage is 0.5-1.2V, preferably 0.8V, pH is 7, and the temperature is 25-30 deg.C. When the diaphragm cathode is applied, the generation rate of protons is suitable for the rate of electron combination provided by a power supply, the current density and the hydrogen production rate reach the maximum value, the system is more stable to operate, and the hydrogen yield is obviously improved.
When the hydrogen-producing membrane is applied to a microbial electrolytic cell, the distance between the membrane and the cathode is reduced by the membrane cathode, the total internal resistance of the microbial electrolytic cell is reduced, compared with a proton exchange membrane, anode acidification and cathode alkalization cannot be caused, pH balance is favorably maintained, the harm of the anode acidification to anode electricity-producing microbes is reduced, hydrogen generated by the cathode is favorably and preferentially diffused to the air chamber by the design of the air chamber, the stay of the hydrogen in a solution is reduced, the hydrogen is prevented from being circulated in the cathode chamber and the anode chamber and being utilized by methanotrophic bacteria to generate methane, the hydrogen is actively and rapidly diffused to the air chamber, and the hydrogen-producing performance of the microbial electrolytic cell is. Unlike the vacuum negative pressure designs mentioned in previous studies, no additional energy supply is required, passive hydrogen evolution is changed into active hydrogen evolution, the sustainability is long, and there is no problem in the negative pressure design-as the active harvest cannot kill methanogens, the temporary closure of the vacuum will restore methane production.
Acetate was chosen as a representative carbon source for this experiment for the following reasons:
acetate is taken as a typical wastewater organic matter, is favorable for the growth of electrogenic bacteria and can represent a carbon source contained in most wastewater, and acetate can be directly produced by fermentation under the anaerobic condition, so that the content is high.
< example 1>
The enrichment of the anode with electrogenic bacteria (mainly Geobacter) in MECs is done in Microbial Fuel Cell (MFC) mode, and the inoculum is from the sewage of sewage plants. For square single-chamber MFC, the cathode seal was opened to expose the air cathode to air, the anode was carbon felt, and the cathode was loaded with trace Pt/C (1mg cm)-2) The carbon cloth as catalyst has two electrodes connected via wires and serially connected resistor (usually 1000 Ω), and the reactor is operated at 25-30 deg.c and oxygen as the electron acceptor in the cathode. The carbon felt anode is enriched with enough electrogenic bacteria after acclimation for about 7-10 days, can effectively degrade organic acetate, and transfers electrons from the anode to the cathode through an external circuitAnd forming a closed loop to finish the discharging process.
Then, the enriched anode is transferred to a microbial electrolytic cell to operate, the microbial electrolytic cell takes the figure 2 as an example, the microbial electrolytic cell takes 1g/L acetate as a substrate, necessary nutrient salts (nitrogen source, phosphorus source, mineral salt and trace elements) are added at the same time, the anode takes a carbon felt as a substrate, an electrogenesis microbial film grows on the carbon felt, and the cathode adopts a titanium net to load trace Pt/C (1mg cm.) to operate-2) As a hydrogen evolution catalyst. The whole reaction is carried out at 25-30 ℃, voltage is applied to 0.6V, generated gas is collected by a gas bag and detected by a gas chromatograph, and gas components in the gas chamber are analyzed after the reactor runs for 20 days. When the current is lower than 1mA, the periodic operation is ended.
< example 2>
The enrichment of the anode with electrogenic bacteria (mainly Geobacter) in MECs is done in Microbial Fuel Cell (MFC) mode, and the inoculum is derived from the sewage of sewage plants. For square single-chamber MFC, the cathode seal was opened to expose the air cathode to air, the anode was carbon felt, and the cathode was loaded with trace Pt/C (1mg cm)-2) The two electrodes are connected by a lead and connected in series with a resistor (generally 1000 omega), and then the reactor is operated in a state that the whole reaction is carried out at 25-30 ℃, and oxygen is used as an electron acceptor of the cathode. The carbon felt anode is enriched with enough electrogenic bacteria after acclimation for about 7-10 days, can effectively degrade organic acetate, and transmits electrons from the anode to the cathode through an external circuit to form a closed loop to finish the discharging process.
Then, the enriched anode is transferred to a microbial electrolytic cell to operate, taking fig. 2 as an example, the microbial electrolytic cell takes 1g/L acetate as a substrate, and simultaneously adds necessary nutrient salts (nitrogen source, phosphorus source, mineral salt and trace elements), the anode adopts a carbon felt as a substrate, and an electrogenesis microbial film grows on the anode; the cathode adopts titanium mesh to load trace Pt/C (1mg cm)-2) As a hydrogen evolution catalyst. The whole reaction is carried out at 25-30 ℃, voltage is applied to 0.8V, generated gas is collected by a gas bag and detected by a gas chromatograph, and gas components in the gas chamber are analyzed after the reactor runs for 20 days. When current flowsAnd when the current value is lower than 1mA, the periodic operation is ended.
< comparative example 1>
The enrichment of the anode with electrogenic bacteria (mainly Geobacter) in MECs is done in Microbial Fuel Cell (MFC) mode, and the inoculum is derived from the sewage of sewage plants. For a square single-chamber MFC, the cathode seal is opened to expose the air cathode to the air, the anode is carbon felt, the cathode is carbon cloth coated with Pt catalyst, the two electrodes are connected by a lead and connected in series with a resistor (generally 1000 omega), at this time, the reactor is operated in a state that the whole reaction is carried out at 25-30 ℃, and oxygen is used as an electron acceptor of the cathode.
Then, the enriched anode is transferred to a microbial electrolytic cell to operate in a state, the microbial electrolytic cell adopts a conventional double-chamber configuration, a proton exchange membrane is taken as a diaphragm, 1g/L acetate is taken as a substrate, necessary nutrient salts (nitrogen source, phosphorus source, mineral salt and trace elements) are added, a carbon felt is taken as a substrate for the anode, and an electrogenesis microbial membrane grows on the anode; the cathode adopts titanium mesh to load trace Pt/C (1mg cm)-2) As a hydrogen evolution catalyst. The whole reaction is carried out at 25-30 ℃, the voltage is applied to 0.8V, the generated gas is collected by a gas bag and detected by a gas chromatograph, and the gas component in the cathode chamber is analyzed after the reactor is operated for 20 days. When the current is lower than 1mA, the periodic operation is ended.
< comparative example 2>
The enrichment of the anode with electrogenic bacteria (mainly Geobacter) in MECs is done in Microbial Fuel Cell (MFC) mode, and the inoculum is derived from the sewage of sewage plants. For a square single-chamber MFC, the cathode seal is opened to expose the air cathode to the air, the anode is carbon felt, the cathode is carbon cloth coated with Pt catalyst, the two electrodes are connected by a lead and connected in series with a resistor (generally 1000 omega), at this time, the reactor is operated in a state that the whole reaction is carried out at 25-30 ℃, and oxygen is used as an electron acceptor of the cathode. The carbon felt anode is enriched with enough electrogenic bacteria after acclimation for about 7-10 days, can effectively degrade organic acetate, and transmits electrons from the anode to the cathode through an external circuit to form a closed loop to finish the discharging process.
Then, transferring the enriched anode to a microbial electrolytic cell for operation, wherein the microbial electrolytic cell adopts a conventional single-chamber configuration, 1g/L acetate is used as a substrate, necessary nutrient salts (nitrogen source, phosphorus source, mineral salt and trace elements) are added, the anode adopts a carbon felt as a substrate, and an electrogenesis microbial film grows on the carbon felt; the cathode adopts titanium mesh to load trace Pt/C (1mg cm)-2) As a hydrogen evolution catalyst. The whole reaction is carried out at 25-30 ℃, voltage is applied to 0.8V, generated gas is collected by a gas bag and detected by a gas chromatograph, and the gas components in the reactor are analyzed after the reactor runs for 20 days. When the current is lower than 1mA, the periodic operation is ended.
The detection method of the average current density comprises the following steps: the data can be recorded in real time by the electrochemical test system.
The detection method of the hydrogen production rate comprises the following steps: using a Gas Chromatograph (GC) with a thermal conductivity sensor, HP-PLOT/U model capillary chromatography column; setting parameters: the injection port temperature is 25 ℃, the shunt temperature is 100 ℃, and the TCD detection temperature is 120 ℃; the different gas components are characterized by residence time, and the reactor cathode anaerobic tube is connected to a trace gas meter (RTK-GMA) through a flexible conduit to measure the volume of gas produced in real time.
The measurement of the average current density and the hydrogen production rate, and the measurement of the gas composition were carried out for examples 1 to 2 and comparative examples 1 to 2 by the above-described methods, and the results are shown in table 1. Wherein the current densities for example 2, comparative example 2 run for 30 days are shown in fig. 3, and the gas composition profile for the GC test after 20 days of example 2, comparative example 2 run is shown in fig. 4, (a) separator cathode MEC; (b) a single chamber MEC.
TABLE 1
Compared with the traditional single-chamber MEC, the design can improve the hydrogen recovery rate and effectively inhibit the generation of methane, and compared with the traditional microbial electrolytic cell with a double-chamber PEM as a diaphragm, the design reduces the internal resistance and improves the current density due to smaller electrode distance, and the price of the PEM membrane is far higher than that of the porous hydrophilic membrane, so that the cost is saved; the traditional catholyte chamber is changed into a gas chamber, so that the collection of hydrogen is promoted, and the hydrogen yield is greatly improved. Compared with electrolytic cells under different voltages, the high voltage is favorable for improving the current density and the hydrogen production rate, but the voltage cannot be too high, because the too high voltage is not favorable for the growth of the electrogenic bacteria, and the energy efficiency is reduced, so the current density of 0.6-0.8V and the hydrogen production rate have obvious advantages, and based on the test of the applicant, the voltage with the applied voltage of 0.5-1.2V is suitable for all electrolytic cells.
As shown in fig. 4, membrane cathode MECs have a predominance of hydrogen gas after 20 days, a small amount of nitrogen due to the fact that all MECs need to be sparged with nitrogen to exclude oxygen before testing to maintain an anaerobic environment for the MECs, which is a normal phenomenon; while the traditional single-chamber MEC has methane gas in about 10 days, it proves that part of hydrogen is converted into methane, which is not beneficial to MEC hydrogen recovery. Hydrogen methanation, once initiated, is difficult to suppress. From the above data analysis, the membrane cathode MEC is very effective in suppressing hydrogen methanation.
The number of apparatuses and the scale of the process described herein are intended to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.
While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.
Claims (7)
1. The diaphragm cathode is characterized by comprising a porous hydrophilic film, a cathode and a porous hydrophobic film which are sequentially packaged.
2. The separator cathode according to claim 1, wherein said porous hydrophilic and hydrophobic films are sealed against both sides of said cathode without a space therebetween.
3. The separator cathode according to claim 1, wherein said cathode is a titanium mesh, a nickel mesh or a carbon cloth, and is loaded with a trace amount of Pt/C (1-5 mg-cm)-2) As a hydrogen evolution catalyst.
4. The microbial electrolytic cell is characterized by comprising an anode chamber, a diaphragm cathode, an air chamber and a power supply, wherein the anode chamber is sequentially packaged without intervals, the diaphragm cathode, the anode chamber and the air chamber are packaged through a sealing component, the anode chamber is provided with a liquid inlet and a gas outlet, an anode is arranged inside the anode chamber, the anode chamber is a liquid chamber, the anode chamber is an anaerobic environment, the air chamber is provided with a gas outlet, and the cathode and the anode are connected in series through an external circuit to the power supply.
5. The microbial electrolysis cell according to claim 4, wherein the anode is a carbon brush or carbon felt as a substrate on which an electrogenic microbial film is grown, and the cathode is a titanium mesh, a nickel mesh or a carbon cloth and loaded with trace amount of Pt/C (1-5 mg-cm)-2) As a hydrogen evolution catalyst.
6. The microbial electrolysis cell of claim 5, wherein the applied voltage is 0.5-1.2V, pH is 7, and temperature is 25-30 ℃.
7. The method for producing hydrogen by using the microbial electrolytic cell is characterized by applying the microbial electrolytic cell of claim 4, and comprises the following specific steps: the microbial electrolytic cell uses 1-5g/L organic matter as substrate, at the same time adds necessary nutrient salt, its anode uses carbon brush or carbon felt as substrate, on which the electrogenesis microbial film is grown, and its cathode uses titanium net, nickel net or carbon cloth to load trace Pt/C (1-5mg cm)-2) As a hydrogen evolution catalyst, the whole reaction is carried out at 25-30 ℃, the pH is 7, the applied voltage is 0.5-1.2V, the generated gas is collected by a gas bag, the organic matters comprise acetate, easily degradable organic matters and/or domestic sewage, the nutritive salts comprise a nitrogen source, a phosphorus source, a nitrogen source, a phosphorus source, a nitrogen source and a nitrogen source, a,Mineral salts and/or trace elements.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN115236150A (en) * | 2022-08-05 | 2022-10-25 | 江苏大学 | Soil self-powered sensor device and heavy metal detection method |
| CN116514234A (en) * | 2023-06-28 | 2023-08-01 | 广东工业大学 | Stack type electrochemical ammonia recovery device and method loaded with pulsed electric field |
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