Method for producing hydrogen and electricity by using biomass

Abstract

The invention belongs to the technical field of microbial energy, and particularly relates to a method for producing hydrogen and electricity by using biomass. According to the method, the thermophilic saccharoanaerobacter is selected, the strain is easy to culture, various saccharides can be used as raw materials, a large amount of biomass can be converted into hydrogen energy and electric energy, and efficient resource utilization of lignocellulose is achieved. Meanwhile, the detoxified hydrolysate is directly adopted as an electron donor and can be used for the microbial fuel cell after simple dilute acid treatment, so that the environmental pollution caused by a detoxification process is avoided, the process steps are simple and easy to operate, only a single strain needs to be added, and the method has a relatively good application prospect. By adopting the synchronous hydrogen and electricity production process, the utilization efficiency of the hydrolysate can be remarkably improved, and the hydrogen yield and the electricity yield are further improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of microbial energy, and in particular relates to a method for producing hydrogen and electricity by utilizing biomass. Background Art

[0002] The energy shortage and environmental pollution caused by the massive consumption of fossil fuels are becoming increasingly serious, which has attracted widespread attention from the international community. In order to alleviate the adverse effects of the rapid consumption of fossil fuels on the environment and climate, researchers from various countries have vigorously carried out research on sustainable energy. my country is a traditional agricultural country with rich biomass resources. As a cheap, easily available and highly value-added resource, its energy conversion will alleviate the energy crisis caused by the massive use of fossil fuels.

[0003] The working principle of microbial fuel cells is to use electrochemically active microorganisms to metabolize substrates and oxidize organic matter into electrical energy. Not only is it pollution-free and has mild reaction conditions, but the substrates are also widely available. It is a new type of green energy generation method and has received widespread attention from scientific researchers. However, microbial fuel cells are restricted by the electrochemical activity of microorganisms, and different electricity-producing microorganisms show obvious differences due to different mechanisms of electron generation and electron transfer. In addition, the current microbial fuel cell technology uses pure compounds to generate electricity, such as glucose, lactic acid, acetic acid, etc., and the application cost is relatively high.

[0004] The prior art discloses a strain of Klebsiella pneumoniae and its application in a microbial fuel cell. The method tests the electrochemical activity of the screened Klebsiella pneumoniae and explores the strain's ability to produce electron mediators and form biofilms for extracellular electron transfer. However, the strain still generates electricity with pure compounds, and the rate of electricity generation is relatively slow.

[0005] The prior art also discloses a method for producing electricity by continuous fermentation of corn straw hydrolyzate by microorganisms, which converts agricultural waste corn straw into electrical energy through bioengineering, achieving green electricity production and efficient resource utilization of agricultural waste. However, this method produces electricity through the joint action of fermentation bacteria and electrogenic bacteria, and its process steps are complicated. The obtained fermentation liquid cannot fully meet the cultivation requirements of electrogenic bacteria, and its substrate conversion rate is relatively low. Summary of the invention

[0006] The purpose of the present invention is to provide a method for producing hydrogen and electricity using biomass. The method provided by the present invention has a simple process and a higher effect of producing hydrogen and electricity.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The present invention provides a method for producing hydrogen and electricity using biomass, comprising the following steps:

[0009] Acid hydrolyzing the biomass to obtain a hydrolyzate, wherein the hydrolyzate contains sugar compounds and has not been detoxified;

[0010] Activating the thermophilic anaerobic bacillus saccharolyticus to obtain a seed solution;

[0011] The hydrolyzate is used as a carbon source, and a culture medium containing the hydrolyzate is injected into the anode chamber of a dual-chamber microbial fuel cell as an anode liquid. After sterilization, the seed liquid is inoculated into the anode liquid to produce hydrogen and electricity under anaerobic conditions.

[0012] Preferably, the acid hydrolysis process is: mixing the biomass and the acidic liquid for acid hydrolysis; the acidic liquid is a sulfuric acid solution; the mass concentration of the acidic liquid is 0.5-4%;

[0013] The ratio of the biomass to the acidic liquid is 10 g: 50-150 mL;

[0014] The acid hydrolysis temperature is 112-130° C. and the time is 15-45 minutes.

[0015] Preferably, the thermophilic anaerobic bacillus saccharolyticus is thermophilic anaerobic bacillus saccharolyticus MJ2, and its deposit number is GDMCC No: 61394.

[0016] Preferably, the seed culture medium used for activation comprises the following ingredients: 5-15 g / L xylan, 1-1.6 g / L ammonium sulfate, 2-3.2 g / L magnesium chloride hexahydrate, 1.41-1.45 g / L potassium dihydrogen phosphate, 5.2-5.8 g / L dipotassium hydrogen phosphate trihydrate, 0.09-0.17 g / L calcium chloride dihydrate, 4-8 g / L sodium β-glycerophosphate pentahydrate, 0.15-0.35 g / L reduced glutathione, 4.2-4.8 g / L yeast powder, 0.5-1.5 g / L ferric chloride hexahydrate, 0.9-1.3 mL / L ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%;

[0017] The pH value of the seed culture medium is 6.8-7.2.

[0018] Preferably, the activation process comprises: adding seed culture medium into a serum bottle, evacuating and filling with inert gas, sterilizing, inoculating the thermosaccharolytic anaerobic bacillus, and activating;

[0019] The activation temperature is 50-60° C., and the activation is carried out under oscillation conditions, the oscillation speed is 120-180 rpm, and the time is 16-20 hours.

[0020] Preferably, the hydrolyzate is calculated based on the total sugar concentration, and the anolyte comprises the following components: 5-15 g / L of hydrolyzate, 1-1.6 g / L of ammonium sulfate, 2-3.2 g / L of magnesium chloride hexahydrate, 1.41-1.45 g / L of potassium dihydrogen phosphate, 5.2-5.8 g / L of dipotassium hydrogen phosphate trihydrate, 0.09-0.17 g / L of calcium chloride dihydrate, 4-8 g / L of sodium β-glycerophosphate pentahydrate, 0.15-0.35 g / L of reduced glutathione, 4.2-4.8 g / L of yeast powder, and 0.9-1.3 mL / L of ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%;

[0021] The pH value of the anolyte is 6.8-7.2.

[0022] Preferably, the cathode chamber of the dual-chamber microbial fuel cell comprises a cathode liquid, the cathode liquid comprises a phosphate buffer containing potassium ferrocyanide, the concentration of the potassium ferrocyanide is 40 to 60 mmol / L, and the pH value of the phosphate buffer is 6.8 to 7.2.

[0023] Preferably, the inoculation amount of the seed solution in the anode solution is 5-15 v / v%; the volume ratio of the anode solution to the cathode solution is 1:1.

[0024] Preferably, the anode chamber further includes an anode, and the cathode chamber further includes a cathode;

[0025] The anode and cathode are both conductive carbon paper; the anode and cathode have the same size;

[0026] The anode and cathode are connected via a resistance load;

[0027] The anode chamber and cathode chamber are separated by a proton exchange membrane.

[0028] Preferably, the temperature of the hydrogen and electricity production is 50-60° C., and the hydrogen and electricity production is carried out under oscillation conditions, the oscillation speed is 120-180 rpm, and the time is 20-28 hours.

[0029] The present invention provides a method for producing hydrogen and electricity by utilizing biomass, comprising the following steps: subjecting biomass to acid hydrolysis to obtain a hydrolyzate, wherein the hydrolyzate contains sugar compounds and has not been detoxified; activating thermophilic anaerobic bacillus saccharolyticus to obtain a seed solution; using the hydrolyzate as a carbon source, injecting a culture medium containing the hydrolyzate as an anode liquid into an anode chamber of a dual-chamber microbial fuel cell, sterilizing, inoculating the seed liquid into the anode liquid, and producing hydrogen and electricity under anaerobic conditions.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention selects thermosaccharolytic anaerobic bacteria, which are easy to culture and can not only use a variety of organic matter as raw materials, but also convert a large amount of biomass into hydrogen energy and electrical energy, thereby achieving efficient resource utilization of lignocellulose.

[0032] (2) The present invention directly uses the undetoxified hydrolyzate as an electron donor, which can be used in a microbial fuel cell after a simple dilute acid treatment, thereby avoiding the environmental pollution caused by the detoxification process. The process steps are simple and easy to operate, and only a single strain needs to be added, which has a good application prospect.

[0033] (3) The synchronous hydrogen and electricity production process adopted by the present invention can significantly improve the utilization efficiency of the hydrolyzate, further increase the hydrogen and electricity production, and the maximum output voltage reaches 321.2mV, and the hydrogen production reaches 101.9mM. The method provided by the present invention not only enriches the diversity of electricity-producing microorganisms, but also expands the resource utilization pathway of lignocellulose, laying a foundation for microbial fuel cells in the field of lignocellulose energy utilization. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 The Gram staining result (left figure) and the transmission electron micrograph (right figure) of the strain Anaerobic Bacillus thermosaccharolyticus MJ2 of the present invention;

[0035] Figure 2 Cyclic voltammetry curves of the microbial fuel cells obtained in Example 1 and Comparative Examples 1 to 3 when performing redox substance detection;

[0036] Figure 3 The differential pulse voltammetry curves of the microbial fuel cells obtained in Example 1 and Comparative Examples 1 to 3 when performing redox substance detection;

[0037] Figure 4 This is a scanning electron microscope image of the anode in Example 1 after producing hydrogen and electricity. DETAILED DESCRIPTION

[0038] The present invention provides a method for producing hydrogen and electricity using biomass, comprising the following steps:

[0039] Acid hydrolyzing the biomass to obtain a hydrolyzate, wherein the hydrolyzate includes sugar compounds and has not been detoxified;

[0040] Activating the thermophilic anaerobic bacillus saccharolyticus to obtain a seed solution;

[0041] The hydrolyzate is used as a carbon source, and a culture medium containing the hydrolyzate is injected into the anode chamber of a dual-chamber microbial fuel cell as an anode liquid. After sterilization, the seed liquid is inoculated into the anode liquid to produce hydrogen and electricity under anaerobic conditions.

[0042] The present invention performs acid hydrolysis on biomass to obtain a hydrolyzate, wherein the hydrolyzate contains sugar compounds.

[0043] In the present invention, the biomass is preferably garden waste. The present invention has no particular limitation on the source of the garden waste, and any source known to those skilled in the art can be used.

[0044] In the present invention, the acid hydrolysis process is preferably: mixing biomass and acidic liquid for acid hydrolysis; the acidic liquid is preferably a sulfuric acid solution; the mass concentration of the acidic liquid is preferably 0.5-4%, more preferably 1%; the amount ratio of the biomass to the acidic liquid is preferably 10g:50-150mL, more preferably 10g:100mL. In the present invention, the temperature of the acid hydrolysis is preferably 112-130°C, more preferably 121°C, and the time is preferably 15-45min, more preferably 30min.

[0045] After the acid hydrolysis, the present invention also preferably includes filtering the obtained acid hydrolysis system. In the present invention, the system after acid hydrolysis is only subjected to simple filtration and impurity removal, and no detoxification treatment is performed. The hydrolyzate that has not been detoxified can also achieve good hydrogen and electricity production. On the one hand, the process steps are simplified, and at the same time, the pollution to the environment caused by the detoxification process is avoided, thereby making the method provided by the present invention have a better application prospect.

[0046] The invention activates the thermophilic anaerobic bacillus saccharolyticus to obtain seed liquid.

[0047] In the present invention, the thermosaccharolytic anaerobic bacillus is preferably thermosaccharolytic anaerobic bacillus MJ2, and its deposit number is GDMCC No: 61394.

[0048] In the present invention, the seed culture medium used for activation preferably comprises the following ingredients: 5-15 g / L xylan, 1-1.6 g / L ammonium sulfate, 2-3.2 g / L magnesium chloride hexahydrate, 1.41-1.45 g / L potassium dihydrogen phosphate, 5.2-5.8 g / L dipotassium hydrogen phosphate trihydrate, 0.09-0.17 g / L calcium chloride dihydrate, 4-8 g / L sodium β-glycerophosphate pentahydrate, 0.15-0.35 g / L reduced glutathione, 4.2-4.8 g / L yeast powder, 0.5-1.5 g / L ferric chloride hexahydrate, 0.9-1.3 g / L ferrous sulfate heptahydrate solution. L / L, the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%, and further preferably: xylan 10g / L, ammonium sulfate 1.3g / L, magnesium chloride hexahydrate 2.6g / L, potassium dihydrogen phosphate 1.43g / L, dipotassium hydrogen phosphate trihydrate 5.5g / L, calcium chloride dihydrate 0.13g / L, β-sodium glycerophosphate pentahydrate 6g / L, reduced glutathione 0.25g / L, yeast powder 4.5g / L, ferric chloride hexahydrate 1g / L, ferrous sulfate heptahydrate solution 1.1mL / L; the pH value of the seed culture medium is preferably 6.8-7.2, and further preferably 7.0.

[0049] In the present invention, the activation process preferably includes: adding seed culture medium to a serum bottle, evacuating and filling with inert gas, inoculating the thermophilic anaerobic bacillus saccharolyticus after sterilization, and activating. In the present invention, the inert gas is preferably nitrogen. The present invention has no special limitation on the sterilization process, and the process well known to those skilled in the art can be adopted. In the present invention, the activation temperature is preferably 50-60°C, more preferably 55°C, the activation is preferably carried out under shaking conditions, the shaking speed is preferably 120-180rpm, more preferably 150rpm, the time is preferably 16-20h, more preferably 18h.

[0050] After obtaining the hydrolyzate and the seed solution, the present invention uses the hydrolyzate as a carbon source, injects a culture medium containing the hydrolyzate as an anode liquid into the anode chamber of a dual-chamber microbial fuel cell, and after sterilization, inoculates the seed solution into the anode liquid to produce hydrogen and electricity under anaerobic conditions.

[0051] In the present invention, the hydrolyzate is calculated based on the total sugar concentration, and the anolyte preferably includes the following ingredients: 5-15 g / L of hydrolyzate, 1-1.6 g / L of ammonium sulfate, 2-3.2 g / L of magnesium chloride hexahydrate, 1.41-1.45 g / L of potassium dihydrogen phosphate, 5.2-5.8 g / L of dipotassium hydrogen phosphate trihydrate, 0.09-0.17 g / L of calcium chloride dihydrate, 4-8 g / L of sodium β-glycerophosphate pentahydrate, 0.15-0.35 g / L of reduced glutathione, 4.2-4.8 g / L of yeast powder, 0.9-1.3 g / L of ferrous sulfate heptahydrate solution. L / L, the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%, and more preferably 10g / L of hydrolyzate, 1.3g / L of ammonium sulfate, 2.6g / L of magnesium chloride hexahydrate, 1.43g / L of potassium dihydrogen phosphate, 5.5g / L of dipotassium hydrogen phosphate trihydrate, 0.13g / L of calcium chloride dihydrate, 6g / L of sodium β-glycerophosphate pentahydrate, 0.25g / L of reduced glutathione, 4.5g / L of yeast powder, and 1.1mL / L of ferrous sulfate heptahydrate solution; the pH value of the anolyte is preferably 6.8-7.2, and more preferably 7.0.

[0052] In the present invention, the cathode chamber of the dual-chamber microbial fuel cell preferably includes a cathode liquid, and the cathode liquid preferably includes a phosphate buffer containing potassium ferrocyanide. The concentration of the potassium ferrocyanide is preferably 40 to 60 mmol / L, and more preferably 50 mmol / L. The pH value of the phosphate buffer is preferably 6.8 to 7.2, and more preferably 7.0.

[0053] In the present invention, the inoculation amount of the seed liquid in the anolyte is preferably 5-15v / v%, more preferably 10v / v%; the volume ratio of the anolyte to the cathode liquid is preferably 1:1. In the present invention, the anode chamber also preferably includes an anode, and the cathode chamber also preferably includes a cathode; the anode and the cathode are preferably conductive carbon paper; the dimensions of the anode and the cathode are preferably the same, and the dimensions are specifically preferably 15×15×0.2mm. In the present invention, the anode and the cathode are preferably connected via a resistive load; the resistance of the resistive load is preferably 2kΩ. In the present invention, the anode chamber and the cathode chamber are preferably separated by a proton exchange membrane, and the proton exchange membrane is preferably a DuPont Nafion-117 membrane.

[0054] In the present invention, the sterilization temperature is preferably 115° C. and the sterilization time is preferably 20 min.

[0055] In the present invention, the temperature of hydrogen and electricity production is preferably 50-60°C, more preferably 55°C, and the hydrogen and electricity production is preferably carried out under oscillation conditions. The oscillation speed is preferably 120-180rpm, more preferably 150rpm, and the time is preferably 20-28h, more preferably 24h.

[0056] Unless otherwise specified, the materials and equipment used in the present invention are all commercially available products in the art.

[0057] The technical solutions in the present invention will be described clearly and completely below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0058] Example 1

[0059] The garden waste is mixed with a sulfuric acid solution with a mass concentration of 1%, wherein the amount ratio of the garden waste to the sulfuric acid solution is 10 g: 100 mL, and the mixture is acid-hydrolyzed at 121° C. for 30 min, and a hydrolyzate is obtained after filtering;

[0060] Add seed culture medium into a serum bottle, evacuate and fill with nitrogen, and sterilize; wherein the seed culture medium comprises the following components: 10 g / L xylan, 1.3 g / L ammonium sulfate, 2.6 g / L magnesium chloride hexahydrate, 1.43 g / L potassium dihydrogen phosphate, 5.5 g / L potassium hydrogen phosphate trihydrate, 0.13 g / L calcium chloride dihydrate, 6 g / L sodium β-glycerophosphate pentahydrate, 0.25 g / L reduced glutathione, 4.5 g / L yeast powder, 1 g / L ferric chloride hexahydrate, 1.1 mL / L ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%; the pH value of the seed culture medium is 7.0; inoculate the thermosaccharolytic anaerobic bacillus MJ2 into the serum bottle, place the serum bottle in a shaker, and perform oscillation activation for 18 hours at a temperature of 55° C. and a rotation speed of 150 rpm to obtain a seed solution;

[0061] The obtained hydrolyzate is used as a carbon source to prepare an anolyte, and the hydrolyzate is calculated based on the total sugar concentration. The anolyte includes the following components: 10 g / L of hydrolyzate, 1.3 g / L of ammonium sulfate, 2.6 g / L of magnesium chloride hexahydrate, 1.43 g / L of potassium dihydrogen phosphate, 5.5 g / L of dipotassium hydrogen phosphate trihydrate, 0.13 g / L of calcium chloride dihydrate, 6 g / L of sodium β-glycerophosphate pentahydrate, 0.25 g / L of reduced glutathione, 4.5 g / L of yeast powder, and 1.1 mL / L of ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is preferably 0.1%; the pH value of the anolyte is 7.0;

[0062] A phosphate buffer solution containing potassium ferrocyanide was used as the cathode liquid, the concentration of the potassium ferrocyanide was 50 mmol / L, and the pH value of the phosphate buffer solution was 7.0; a DuPont Nafion-117 membrane was used as the proton exchange membrane, and conductive carbon paper was used as the cathode and anode, respectively, the dimensions of the cathode and the anode were both 15×15×0.2 mm, a double-chamber microbial fuel cell was constructed, and the cathode and the anode were connected with a 2 kΩ resistor load;

[0063] 90 mL of anolyte was injected into the anode chamber, and 100 mL of cathode liquid was injected into the cathode chamber. Nitrogen was simultaneously filled into the cathode chamber and the anode chamber for 30 min to place the double chambers in an anaerobic environment. After sterilization at 115° C. for 20 min, 10 mL of seed liquid was inoculated into the anode liquid. The microbial fuel cell was then placed in a shaker and shaken at a temperature of 55° C. and a rotation speed of 150 rpm for 24 h to produce hydrogen and electricity in the first cycle.

[0064] After oscillating for 24 hours, 90% of the liquid in the anode chamber and cathode chamber was removed, and the same volume of new anode liquid and cathode liquid were added to 100 mL respectively, and nitrogen was refilled. The oscillation was continued at a temperature of 55°C and a rotation speed of 150 rpm for 24 hours to complete the second cycle of hydrogen and electricity production.

[0065] Example 2

[0066] The garden waste is mixed with a sulfuric acid solution with a mass concentration of 2%, wherein the amount ratio of the garden waste to the sulfuric acid solution is 10 g: 80 mL, and acid hydrolyzed at 115° C. for 20 min, and a hydrolyzate is obtained after filtering;

[0067] Add seed culture medium into a serum bottle, evacuate and fill with nitrogen, and sterilize; wherein the seed culture medium comprises the following components: 10 g / L xylan, 1.3 g / L ammonium sulfate, 2.6 g / L magnesium chloride hexahydrate, 1.43 g / L potassium dihydrogen phosphate, 5.5 g / L potassium hydrogen phosphate trihydrate, 0.13 g / L calcium chloride dihydrate, 6 g / L sodium β-glycerophosphate pentahydrate, 0.25 g / L reduced glutathione, 4.5 g / L yeast powder, 1 g / L ferric chloride hexahydrate, 1.1 mL / L ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%; the pH value of the seed culture medium is 7.0; inoculate the thermosaccharolytic anaerobic bacillus MJ2 into the serum bottle, place the serum bottle in a shaker, and perform oscillation activation for 16 hours at a temperature of 55° C. and a rotation speed of 120 rpm to obtain a seed solution;

[0068] The obtained hydrolyzate is used as a carbon source to prepare an anolyte, and the hydrolyzate is calculated based on the total sugar concentration. The anolyte includes the following components: 10 g / L of hydrolyzate, 1.3 g / L of ammonium sulfate, 2.6 g / L of magnesium chloride hexahydrate, 1.43 g / L of potassium dihydrogen phosphate, 5.5 g / L of dipotassium hydrogen phosphate trihydrate, 0.13 g / L of calcium chloride dihydrate, 6 g / L of sodium β-glycerophosphate pentahydrate, 0.25 g / L of reduced glutathione, 4.5 g / L of yeast powder, and 1.1 mL / L of ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is preferably 0.1%; the pH value of the anolyte is 7.0;

[0069] A phosphate buffer solution containing potassium ferrocyanide was used as the cathode liquid, the concentration of the potassium ferrocyanide was 50 mmol / L, and the pH value of the phosphate buffer solution was 7.0; a DuPont Nafion-117 membrane was used as the proton exchange membrane, and conductive carbon paper was used as the cathode and anode, respectively, the dimensions of the cathode and the anode were both 15×15×0.2 mm, a double-chamber microbial fuel cell was constructed, and the cathode and the anode were connected with a 2 kΩ resistor load;

[0070] 80 mL of anolyte was injected into the anode chamber, 100 mL of cathode liquid was injected into the cathode chamber, nitrogen was simultaneously filled into the cathode chamber and the anode chamber for 30 min, so that the double chambers were in an anaerobic environment, and after sterilization at 115° C. for 20 min, 20 mL of seed liquid was inoculated into the anode liquid, and then the microbial fuel cell was placed in a shaker and shaken at a temperature of 55° C. and a rotation speed of 150 rpm for 24 h to produce hydrogen and electricity in the first cycle;

[0071] After oscillating for 24 hours, 90% of the liquid in the anode chamber and cathode chamber was removed, and the same volume of new anode liquid and cathode liquid were added to 100 mL respectively, and nitrogen was refilled. The oscillation was continued at a temperature of 55°C and a rotation speed of 150 rpm for 24 hours to complete the second cycle of hydrogen and electricity production.

[0072] Example 3

[0073] The garden waste is mixed with a sulfuric acid solution with a mass concentration of 3%, wherein the amount ratio of the garden waste to the sulfuric acid solution is 10 g: 120 mL, and acid hydrolyzed at 125° C. for 40 min, and a hydrolyzate is obtained after filtering;

[0074] Add seed culture medium into a serum bottle, evacuate and fill with nitrogen, and sterilize; wherein the seed culture medium comprises the following components: 10 g / L xylan, 1.3 g / L ammonium sulfate, 2.6 g / L magnesium chloride hexahydrate, 1.43 g / L potassium dihydrogen phosphate, 5.5 g / L potassium hydrogen phosphate trihydrate, 0.13 g / L calcium chloride dihydrate, 6 g / L sodium β-glycerophosphate pentahydrate, 0.25 g / L reduced glutathione, 4.5 g / L yeast powder, 1 g / L ferric chloride hexahydrate, 1.1 mL / L ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%; the pH value of the seed culture medium is 7.0; inoculate the thermosaccharolytic anaerobic bacillus MJ2 into the serum bottle, place the serum bottle in a shaker, and perform oscillation activation for 20 hours at a temperature of 55° C. and a rotation speed of 180 rpm to obtain a seed solution;

[0075] The obtained hydrolyzate is used as a carbon source to prepare an anolyte, and the hydrolyzate is calculated based on the total sugar concentration. The anolyte includes the following components: 10 g / L of hydrolyzate, 1.3 g / L of ammonium sulfate, 2.6 g / L of magnesium chloride hexahydrate, 1.43 g / L of potassium dihydrogen phosphate, 5.5 g / L of dipotassium hydrogen phosphate trihydrate, 0.13 g / L of calcium chloride dihydrate, 6 g / L of sodium β-glycerophosphate pentahydrate, 0.25 g / L of reduced glutathione, 4.5 g / L of yeast powder, and 1.1 mL / L of ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is preferably 0.1%; the pH value of the anolyte is 7.0;

[0076] A phosphate buffer solution containing potassium ferrocyanide was used as the cathode liquid, the concentration of the potassium ferrocyanide was 50 mmol / L, and the pH value of the phosphate buffer solution was 7.0; a DuPont Nafion-117 membrane was used as the proton exchange membrane, and conductive carbon paper was used as the cathode and anode, respectively, the dimensions of the cathode and the anode were both 15×15×0.2 mm, a double-chamber microbial fuel cell was constructed, and the cathode and the anode were connected with a 2 kΩ resistor load;

[0077] 95 mL of anolyte was injected into the anode chamber, and 100 mL of catholyte was injected into the cathode chamber. Nitrogen was simultaneously filled into the cathode chamber and the anode chamber for 30 min to place the double chambers in an anaerobic environment. After sterilization at 115° C. for 20 min, 5 mL of seed solution was inoculated into the anode solution. The microbial fuel cell was then placed in a shaker and shaken at a temperature of 55° C. and a rotation speed of 150 rpm for 24 h to produce hydrogen and electricity in the first cycle.

[0078] After oscillating for 24 hours, 90% of the liquid in the anode chamber and cathode chamber was removed, and the same volume of new anode liquid and cathode liquid were added to 100 mL respectively, and nitrogen was refilled. The oscillation was continued at a temperature of 55°C and a rotation speed of 150 rpm for 24 hours to complete the second cycle of hydrogen and electricity production.

[0079] Comparative Example 1

[0080] Hydrogen and electricity were produced according to Example 1, except that the hydrolyzate in the anode liquid was replaced with xylan.

[0081] Comparative Example 2

[0082] Hydrogen and electricity are produced according to Example 1, except that the hydrolyzate in the anode liquid is replaced by xylose.

[0083] Comparative Example 3

[0084] Hydrogen and electricity are produced according to Example 1, except that the hydrolyzate in the anode liquid is replaced with arabinose.

[0085] Performance Testing

[0086] Test Example 1

[0087] Morphological characteristics of strains

[0088] (1) Optical microscopic observation of the thermosaccharolytic anaerobic bacillus: The strain was cultured in an activated medium until the logarithmic growth phase, and the strain morphology was observed under an optical microscope using Gram staining. Figure 1 The Gram staining results (left) and transmission electron micrograph of the strain MJ2 (right) are shown.

[0089] The results showed that the Gram staining result was red, indicating that the thermosaccharolytic anaerobic bacillus MJ2 provided by the present invention was a Gram-negative anaerobic bacterium.

[0090] (2) Transmission electron microscopy observation of thermosaccharolytic anaerobic bacteria: The strain was cultured in an activation medium until the logarithmic growth phase, the cells were centrifuged and fixed with 2.5% glutaraldehyde, and the strain morphology was observed under a transmission electron microscope. The results showed that thermosaccharolytic anaerobic bacteria MJ2 was short rod-shaped, 1.5 μm long and 0.25 μm wide, with pili.

[0091] Test Example 2

[0092] For Examples 1 to 3 and Comparative Examples 1 to 3, during the process of producing hydrogen and electricity, a data acquisition device (OW18D intelligent multimeter, Fujian Lilipu Optoelectronics Technology Co., Ltd.) was connected between the anode and the cathode to record the output voltage; the results are shown in Table 1;

[0093] For Examples 1 to 3 and Comparative Examples 1 to 3, after the second cycle, the hydrogen production in the anode chamber was measured by gas chromatography; the results are shown in Table 1;

[0094] Table 1 Output voltage and hydrogen production during power generation in Examples 1 to 3 and Comparative Examples 1 to 3

[0095]

[0096] Test Example 3

[0097] The redox substances of the microbial fuel cells obtained in Example 1 and Comparative Examples 1 to 3 were detected;

[0098] With the anode as the working electrode, the cathode as the counter electrode, and Ag / AgCl as the reference electrode, the electrochemical workstation (CHI650E, Shanghai Chenhua Instrument Co., Ltd.) was used to measure the anodic cyclic voltammetry (CV) curve. The test conditions were: initial potential of -1.6 V, upper limit potential of 1.6 V, lower limit potential of -1.6 V, sampling interval of 0.001 V, and scanning speed of 40 mV / s. Further, the anodic differential pulse voltammetry (DPV) curve was measured. The test conditions were: initial potential of 0.2 V, end point potential of 1.2 V, amplitude of 0.05 V, and pulse width of 0.05 s.

[0099] Figure 2 is the cyclic voltammetry curve; Figure 3 is the differential pulse voltammetry curve;

[0100] Depend on Figure 2 and Figure 3 It can be seen that the cyclic voltammetry curve with the hydrolyzate as the substrate shows a redox peak, and the differential pulse voltammetry curve shows an obvious anodic oxidation peak, indicating that extracellular electron transfer can be carried out through electron mediators; using xylan as the substrate (Comparative Example 1), compared with the hydrolyzate, the same redox peak can be detected, but its peak intensity is higher than that of the hydrolyzate; using xylose as the substrate (Comparative Example 2), compared with the hydrolyzate, the same redox peak can be detected, and its peak intensity is equivalent to that of the hydrolyzate; using arabinose as the substrate (Comparative Example 3), compared with the hydrolyzate, the same redox peak can be detected, but its peak intensity is lower than that of the hydrolyzate.

[0101] Test Example 4

[0102] In Example 1, after the first cycle and the second cycle, the anode was removed, cut into small pieces of 2×2 mm, fixed with 2.5% glutaraldehyde, and observed under a scanning electron microscope. Figure 4 The left figure is the scanning electron microscope image of the anode. The right figure is the scanning electron microscope image of the anode after the first cycle. It can be seen that after the end of both cycles, the attachment of microorganisms can be observed on the anode surface, indicating that the thermosaccharolytic anaerobic bacillus MJ2 can transfer extracellular electrons through biofilm contact.

[0103] In summary, it can be seen that the thermosaccharolytic anaerobic bacillus MJ2 is electroactive and can transfer extracellular electrons through endogenous electron mediators synthesized by itself and by attaching to the anode to form a biofilm. In addition, it can also use a variety of sugars to co-produce electricity and hydrogen energy, especially when the hydrolyzate of undetoxified garden waste is used as an electron donor, the hydrogen production and electricity production are equivalent to that when xylose is used as a substrate, and higher than that when arabinose is used as a substrate.

[0104] Although the above embodiment describes the present invention in detail, it is only a part of the embodiments of the present invention, not all of the embodiments. Other embodiments can be obtained based on this embodiment without creativity, and these embodiments all fall within the protection scope of the present invention.

Claims

1. A method for producing hydrogen and electricity using biomass, characterized in that: The following steps are involved: Acid hydrolyzing the biomass to obtain a hydrolyzate, wherein the hydrolyzate contains sugar compounds and has not been detoxified; Activating the thermophilic anaerobic bacillus saccharolyticus to obtain a seed solution; The hydrolyzate is used as a carbon source, and a culture medium containing the hydrolyzate is injected into the anode chamber of a dual-chamber microbial fuel cell as an anode liquid. After sterilization, the seed liquid is inoculated into the anode liquid to produce hydrogen and electricity under anaerobic conditions.

2. The method according to claim 1, characterized in that The acid hydrolysis process is as follows: mixing biomass and acidic liquid for acid hydrolysis; the acidic liquid is a sulfuric acid solution; the mass concentration of the acidic liquid is 0.5-4%; The ratio of the biomass to the acidic liquid is 10 g: 50-150 mL; The acid hydrolysis temperature is 112-130° C. and the time is 15-45 minutes.

3. The method according to claim 1, characterized in that The thermophilic anaerobic bacillus saccharolyticus is thermophilic anaerobic bacillus saccharolyticus MJ2, and its deposit number is GDMCC No: 61394.

4. The method according to claim 1 or 3, characterized in that: The seed culture medium used for activation comprises the following components: 5-15 g / L xylan, 1-1.6 g / L ammonium sulfate, 2-3.2 g / L magnesium chloride hexahydrate, 1.41-1.45 g / L potassium dihydrogen phosphate, 5.2-5.8 g / L dipotassium hydrogen phosphate trihydrate, 0.09-0.17 g / L calcium chloride dihydrate, 4-8 g / L sodium β-glycerophosphate pentahydrate, 0.15-0.35 g / L reduced glutathione, 4.2-4.8 g / L yeast powder, 0.5-1.5 g / L ferric chloride hexahydrate, 0.9-1.3 mL / L ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%; The pH value of the seed culture medium is 6.8-7.

2.

5. The method according to claim 4, characterized in that The activation process comprises: adding seed culture medium into a serum bottle, evacuating and filling with inert gas, sterilizing, inoculating the thermophilic anaerobic bacillus saccharolyticus, and activating; The activation temperature is 50-60° C., and the activation is carried out under oscillation conditions, the oscillation speed is 120-180 rpm, and the time is 16-20 hours.

6. The method according to claim 1, characterized in that The hydrolyzate is calculated based on the total sugar concentration, and the anolyte comprises the following components: 5-15 g / L of hydrolyzate, 1-1.6 g / L of ammonium sulfate, 2-3.2 g / L of magnesium chloride hexahydrate, 1.41-1.45 g / L of potassium dihydrogen phosphate, 5.2-5.8 g / L of dipotassium hydrogen phosphate trihydrate, 0.09-0.17 g / L of calcium chloride dihydrate, 4-8 g / L of sodium β-glycerophosphate pentahydrate, 0.15-0.35 g / L of reduced glutathione, 4.2-4.8 g / L of yeast powder, and 0.9-1.3 mL / L of ferrous sulfate heptahydrate solution, wherein the mass concentration of the ferrous sulfate heptahydrate solution is 0.1%; The pH value of the anolyte is 6.8-7.

2.

7. The method according to claim 6, characterized in that The cathode chamber of the dual-chamber microbial fuel cell comprises cathode liquid, and the cathode liquid comprises phosphate buffer containing potassium ferrocyanide, the concentration of the potassium ferrocyanide is 40-60 mmol / L, and the pH value of the phosphate buffer is 6.8-7.

2.

8. The method according to claim 6 or 7, characterized in that: The inoculation amount of the seed solution in the anode solution is 5-15 v / v%; the volume ratio of the anode solution to the cathode solution is 1:

1.

9. The method according to claim 1, characterized in that: The anode chamber also includes an anode, and the cathode chamber also includes a cathode; The anode and cathode are both conductive carbon paper; the anode and cathode have the same size; The anode and cathode are connected via a resistance load; The anode chamber and cathode chamber are separated by a proton exchange membrane.

10. The method according to claim 1, characterized in that The temperature for producing hydrogen and electricity is 50-60° C., and the hydrogen and electricity are produced under oscillation conditions. The oscillation speed is 120-180 rpm and the time is 20-28 hours.

Images