Preparation of waste vinasse-based thermosetting material and application of waste vinasse-based thermosetting material in photo-thermoelectric generator

Abstract

The invention discloses preparation of a waste vinasse-based thermosetting material and application of the waste vinasse-based thermosetting material in a photo-thermal electric generator, and relates to the technical field of high-value utilization of biomass waste, and the preparation comprises the following steps: pouring waste vinasse into a sodium periodate aqueous solution, heating and stirring under a dark condition to generate oxidized waste vinasse; then washing with deionized water to remove unreacted sodium periodate, and drying the remaining washed oxidized waste vinasse in a drying oven; and putting the dried oxidized waste vinasse into a hot press, carrying out hot pressing, and drying to form the waste vinasse-based thermosetting material. According to the method, sodium periodate can be used for selective in-situ oxidation of effective components in the waste vinasse, adhesive-free bonding is achieved through one-step hot press molding, and meanwhile the method can be applied to preparation of a photo-thermoelectric generator.

Description

Technical Field

[0001] The present invention relates to the technical field of high-value utilization of biomass waste, and particularly to the preparation of distiller's grains-based thermosetting materials and their application in photovoltaic thermal generators. Background Art

[0002] Distiller's grains (DG) are the residues after solid-state fermentation and distillation of biomass raw materials such as corn, sorghum, wheat, and barley under the action of a complex microbial system. They are typical by-products of the traditional Chinese fermented food industry. It is worth noting that the production of only one ton of liquor will generate 3-4 tons of DG. Considering this huge output, the efficient treatment and utilization of DG remain a key but challenging issue in the industry. Traditional methods for using DG include composting and using as animal feed, but these methods have obvious limitations. First, DG has a high water content and complex composition, and will decompose rapidly during storage, leaching out organic pollutants with acidic and high chemical oxygen demand (COD), posing a threat to environmental safety. Second, DG has a high content of cellulose and lignin, resulting in poor feed palatability, and the digestibility is only suitable for certain ruminants, so the potential value of distiller's grains cannot be fully exploited. Therefore, exploring efficient methods to achieve the high-value utilization of brewing waste DG has important practical significance.

[0003] Numerous studies have explored the reuse of DG, including the preparation of carbon materials by hydrothermal or pyrolysis methods, and the purification of bioactive components (such as dipeptide compounds) for the biomedical field. In recent years, researchers have focused on adding DG as a filler to polymer composites to enhance their value. However, these composites mainly rely on synthetic polymers derived from non-renewable fossil resources. In addition, the pretreatment usually only includes basic cleaning and crushing, resulting in low surface activity of the obtained DG particles and weak interactions between particles. Even when using adhesives, poor adhesion between DG and polymers will produce defects, leading to stress concentration and poor mechanical properties of the material when bearing loads. Therefore, surface chemical modification of DG is crucial for improving material properties. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art, and provide the preparation of distiller's grains-based thermosetting materials and their application in photovoltaic thermal generators. Sodium periodate is used to selectively oxidize the effective components in distiller's grains in-situ, and binder-free bonding is achieved through one-step hot pressing molding, and it is applied in the preparation of photovoltaic thermal generators.

[0005] The purpose of the present invention is achieved through the following technical solutions: The preparation of a distiller's grains-based thermosetting material includes the following steps:

[0006] S1. Weigh 5 - 10 g of distiller's grains and pour them into an aqueous solution of sodium periodate. Under dark conditions, heat and stir for 2 - 10 h to produce oxidized distiller's grains. Then wash them 3 times with deionized water to remove unreacted sodium periodate, and put the remaining washed oxidized distiller's grains into an oven to dry for 12 h.

[0007] S2. Put the dried oxidized distiller's grains into a hot press and perform hot pressing at a pressure of 2 - 5 MPa to dry and form a distiller's grains - based thermosetting material.

[0008] In the step S1, the distiller's grains can be sorghum distiller's grains or corn distiller's grains.

[0009] In the step S1, the concentration of sodium periodate in the aqueous solution of sodium periodate is 45 mg / ml. If the concentration is too high, the oxidation reaction will be too intense, making it difficult to control the reaction process and resulting in poor chemical stability. If the concentration is too low, the kinetic rate of the oxidation reaction will decrease, possibly leading to an extended reaction time or even an incomplete reaction. The mass ratio of the distiller's grains to sodium periodate is 5:9 or 5:18.

[0010] In the step S1, the heating and stirring temperature is 50 °C. If the temperature is too high, sodium periodate will decompose too quickly, reducing the oxidation efficiency and generating iodate impurities. If the temperature is too low, the reaction rate will be affected.

[0011] In the step S1, the drying temperature in the oven is 105 °C. If the drying temperature is too high, it will cause carbonization, and if the drying temperature is too low, it will result in incomplete drying.

[0012] In the step S2, the hot pressing temperature of the hot press is 100 - 110 °C, and the hot pressing time is 0.5 - 2 h. If the hot pressing temperature is too high or the hot pressing time is too long, it will cause carbonization. If the hot pressing temperature is too low or the hot pressing time is too short, it will not be able to form.

[0013] An application of a distiller's grains - based thermosetting material in a photo - thermoelectric generator. The photo - thermoelectric generator is composed of a distiller's grains - based thermosetting material, a thermoelectric module, and a cooling module.

[0014] The thickness of the distiller's grains - based thermosetting material is 0.5 mm - 1 mm.

[0015] The beneficial effects of the present invention are:

[0016] 1. Without the need to use additional adhesives, the present invention uses sodium periodate to selectively and in - situ oxidize the effective components (cellulose and lignin) in the distiller's grains, and realizes binder - free bonding through one - step hot pressing. During this process, a cross - linked network is formed at the interface of the distiller's grains through covalent bonds and hydrogen bonds. The obtained distiller's grains - based thermosetting material (ODGT) has excellent mechanical properties, thermal stability, and solvent resistance.

[0017] 2. The oxidized spent grains reflected by the present invention have a maximum aldehyde group content of up to 3.90 mmol / g.

[0018] 3. The fracture strength and Young's modulus of the spent-grain-based thermosetting material of the present invention can reach up to 20.55 MPa and 20.43 GPa respectively.

[0019] 4. The novel photo-thermal-electric generator made of the spent-grain-based thermosetting material prepared by the present invention has an output voltage and current that can reach up to 323.63 mV and 58.36 mA respectively.

[0020] 5. The spent-grain-based thermosetting material of the present invention not only has a simple and efficient preparation process without the use of additional adhesives, but also its internal stable cross-linked network endows the material with excellent mechanical properties, thermal stability and solvent resistance. This not only provides an innovative solution for the high-value utilization of spent grains, but also opens up a new way for functional materials derived entirely from biomass.

[0021] 6. The spent-grain-based thermosetting material prepared by the present invention can be industrially produced on a large scale due to its wide raw material sources and simple preparation process. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the spent-grain-based thermosetting material prepared by the present invention;

[0023] Figure 2 It is a mechanical property diagram of the spent-grain-based thermosetting material. ODGT-2 in (a) refers to the in-situ oxidation time of spent grains of 2 h, ODGT-4 refers to the in-situ oxidation time of spent grains of 4 h, ODGT-6 refers to the in-situ oxidation time of spent grains of 6 h, ODGT-8 refers to the in-situ oxidation time of spent grains of 8 h, and ODGT-10 refers to the in-situ oxidation time of spent grains of 10 h; the red in (b) refers to the tensile fracture strength at different in-situ oxidation times, and the blue refers to the elongation at break at different in-situ oxidation times; (c) shows the toughness at different in-situ oxidation times; (d) shows the Young's modulus at different in-situ oxidation times;

[0024] Figure 3Output voltage and output current diagrams of a photo-thermal-electric generator made of the spent grains-based thermosetting material prepared by the present invention. In (a), it is the output current of the photo-thermal-electric generator under simulated sunlight with different intensities in air; in (b), it is the output voltage of the photo-thermal-electric generator under simulated sunlight with different intensities in air; in (c), it is the output current of the photo-thermal-electric generator under simulated sunlight with different intensities in ice; in (d), it is the output voltage of the photo-thermal-electric generator under simulated sunlight with different intensities in ice; in (e), it is the output current of the photo-thermal-electric generator under simulated sunlight with different intensities in water; in (f), it is the output voltage of the photo-thermal-electric generator under simulated sunlight with different intensities in water;

[0025] Figure 4 Output performance diagrams of a photo-thermal-electric generator made of the spent grains-based thermosetting material prepared by the present invention in different media, where the output performance includes power density, power, current, and voltage. Specific embodiments

[0026] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the present invention claimed, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0027] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0028] In the first embodiment of the present application:

[0029] (1) In-situ oxidation of spent grains:

[0030] Add 5 g of spent grains powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in a dark environment at 50 °C for 2 h. After the reaction, wash the reaction product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0031] (2) Preparation of spent grains-based thermosetting material:

[0032] The oxidized waste distillers grains ODG was hot-pressed at 100 °C and 2 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.5 mm. The tensile fracture strength of the obtained material was 16.41 MPa, the elongation at break was 0.88%, the Young's modulus was 10.05 GPa, and the toughness was 0.09 MJ / m 3 .

[0033] (3) Preparation of the photo-thermal-electric generator:

[0034] The photo-thermal-electric generator consists of: waste distillers grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. The temperature cooling mode is selected according to the environment, and then the assembled photo-thermal-electric generator is irradiated under simulated sunlight (simulated sunlight is 100 mW / cm 2 ), and its output voltage and current are recorded. The highest output voltage is 320.12 mV, and the output current is 53.35 mA.

[0035] In the second embodiment of the present application:

[0036] (1) In-situ oxidation of waste distillers grains:

[0037] 5 g of waste distillers grains powder DG and 18 g of sodium periodate NaIO4 were added to 400 ml of deionized water, and the mixture was reacted in a dark environment at 50 °C for 4 h. After the reaction, the product was washed with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then the washed material was dried at 35 °C to obtain oxidized waste distillers grains ODG.

[0038] (2) Preparation of waste distillers grains-based thermosetting material:

[0039] The oxidized waste distillers grains ODG was hot-pressed at 100 °C and 2 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.5 mm. The tensile fracture strength of the obtained material was 20.41 MPa, the elongation at break was 0.99%, the Young's modulus was 11.25 GPa, and the toughness was 0.10 MJ / m 3 .

[0040] (3) Preparation of the photo-thermal-electric generator:

[0041] The photo-thermal-electric generator consists of: waste distillers grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. The temperature cooling mode is selected according to the environment, and then the assembled photo-thermal-electric generator is irradiated under simulated sunlight (simulated sunlight is 100 mW / cm2 ), record its output voltage and current. The highest output voltage is 318.12 mV and the output current is 55.35 mA.

[0042] In the third embodiment of the present application:

[0043] (1) In-situ oxidation of spent grains:

[0044] Add 5 g of spent grain powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in a dark environment at 50 °C for 6 h. After the reaction is completed, wash the product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0045] (2) Preparation of spent grain-based thermosetting material:

[0046] Hot-press the oxidized spent grains ODG at 100 °C under a pressure of 2 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.5 mm. The obtained material has a tensile fracture strength of 20.12 MPa, an elongation at break of 1.12%, a Young's modulus of 13.25 GPa, and a toughness of 0.11 MJ / m3.

[0047] (3) Preparation of the photo-thermal-electric generator:

[0048] The photo-thermal-electric generator consists of: a spent grain-based thermosetting material, a hot spot module, and a cooling module. The cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. Select the temperature cooling mode according to the environment, and then place the assembled photo-thermal-electric generator under simulated sunlight irradiation (simulated sunlight is 100 mW / cm2), record its output voltage and current. The highest output voltage is 315.12 mV and the output current is 51.35 mA.

[0049] In the fourth embodiment of the present application:

[0050] (1) In-situ oxidation of spent grains:

[0051] Add 5 g of spent grain powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in a dark environment at 50 °C for 8 h. After the reaction is completed, wash the product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0052] (2) Preparation of spent grain-based thermosetting material:

[0053] The oxidized waste distillers grains ODG was hot-pressed at 100 °C and a pressure of 2 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.5 mm. The tensile fracture strength of the obtained material was 20.05 MPa, the elongation at break was 1.11%, the Young's modulus was 14.25 GPa, and the toughness was 0.10 MJ / m 3 .

[0054] (3) Preparation of the photo-thermal-electric generator:

[0055] The photo-thermal-electric generator consists of: waste distillers grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. The temperature cooling mode is selected according to the environment. Then, the assembled photo-thermal-electric generator is irradiated under simulated sunlight (simulated sunlight is 100 mW / cm 2 ), and its output voltage and current are recorded. The highest output voltage is 321.33 mV, and the output current is 54.39 mA.

[0056] In the fifth embodiment of this application:

[0057] (1) In-situ oxidation of waste distillers grains:

[0058] 5 g of waste distillers grains powder DG and 18 g of sodium periodate NaIO4 were added to 400 ml of deionized water. The mixture was reacted in a dark environment at 50 °C for 10 h. After the reaction, the product was washed with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then, the washed material was dried at 35 °C to obtain oxidized waste distillers grains ODG.

[0059] (2) Preparation of waste distillers grains-based thermosetting material:

[0060] The oxidized waste distillers grains ODG was hot-pressed at 100 °C and a pressure of 2 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.5 mm. The tensile fracture strength of the obtained material was 19.10 MPa, the elongation at break was 1.03%, the Young's modulus was 19.25 GPa, and the toughness was 0.10 MJ / m 3 .

[0061] (3) Preparation of the photo-thermal-electric generator:

[0062] The photo-thermal-electric generator consists of: waste distillers grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. The temperature cooling mode is selected according to the environment. Then, the assembled photo-thermal-electric generator is irradiated under simulated sunlight (simulated sunlight is 100 mW / cm 2) Record its output voltage and current. The highest output voltage is 302.42 mV, and the output current is 50.12 mA.

[0063] In the sixth embodiment of the present application:

[0064] (1) In-situ oxidation of spent grains:

[0065] Add 10 g of spent grain powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in a dark environment at 50 °C for 2 h. After the reaction, wash the product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0066] (2) Preparation of spent grain-based thermosetting material:

[0067] Hot press the oxidized spent grains ODG at 110 °C and a pressure of 5 MPa for 2 h to prepare a thermosetting material ODGT with a thickness of 0.75 mm. As shown in Figure 2 (b), the tensile fracture strength of the obtained material is 18.41 MPa, the elongation at break is 0.76%, the Young's modulus is 10.17 GPa, and the toughness is 0.07 MJ / m 3 .

[0068] (3) Preparation of a photo-thermal-electric generator:

[0069] The photo-thermal-electric generator consists of: a spent grain-based thermosetting material, a hot spot module, and a cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. Select the temperature cooling mode according to the environment, and then place the assembled photo-thermal-electric generator under simulated sunlight irradiation (simulated sunlight is 100 mW / cm 2 ), record its output voltage and current. The highest output voltage is 323.64 mV, and the output current is 58.36 mA.

[0070] In the seventh embodiment of the present application:

[0071] (1) In-situ oxidation of spent grains:

[0072] Add 10 g of spent grain powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in a dark environment at 50 °C for 4 h. After the reaction, wash the product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0073] (2) Preparation of spent grain-based thermosetting material:

[0074] The oxidized waste distillers grains ODG was hot-pressed at 110 °C and a pressure of 5 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.75 mm. The tensile fracture strength of the obtained material was 19.54 MPa, the elongation at break was 0.92%, the Young's modulus was 14.48 GPa, and the toughness was 0.09 MJ / m 3 .

[0075] (3) Preparation of the photo-thermal-electric generator:

[0076] The photo-thermal-electric generator consists of: waste distillers grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. Select the temperature cooling mode according to the environment, and then place the assembled photo-thermal-electric generator under simulated sunlight irradiation (simulated sunlight is 100 mW / cm 2 ), and record its output voltage and current. The highest output voltage is 303.32 mV, and the output current is 49.35 mA.

[0077] In the eighth embodiment of the present application:

[0078] (1) In-situ oxidation of waste distillers grains:

[0079] 10 g of waste distillers grains powder DG and 18 g of sodium periodate NaIO4 were added to 400 ml of deionized water. The mixture was reacted in a dark environment at 50 °C for 6 h. After the reaction, the product was washed with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then the washed material was dried at 35 °C to obtain oxidized waste distillers grains ODG.

[0080] (2) Preparation of waste distillers grains-based thermosetting material:

[0081] The oxidized waste distillers grains ODG was hot-pressed at 110 °C and a pressure of 5 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.75 mm. The tensile fracture strength of the obtained material was 20.55 MPa, the elongation at break was 1.31%, the Young's modulus was 15.52 GPa, and the toughness was 0.14 MJ / m 3 .

[0082] (3) Preparation of the photo-thermal-electric generator:

[0083] The photo-thermal-electric generator consists of: waste distillers grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. Select the temperature cooling mode according to the environment, and then place the assembled photo-thermal-electric generator under simulated sunlight irradiation (simulated sunlight is 100 mW / cm2 ) Record its output voltage and current. The maximum output voltage is 300.15 mV, and the output current is 50.66 mA.

[0084] In the ninth embodiment of the present application:

[0085] (1) In-situ oxidation of spent grains:

[0086] Add 10 g of spent grain powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in the dark at 50 °C for 8 h. After the reaction, wash the product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0087] (2) Preparation of spent grain-based thermosetting material:

[0088] Hot-press the oxidized spent grains ODG at 110 °C and a pressure of 5 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.75 mm. The tensile fracture strength of the obtained material is 20.25 MPa, the elongation at break is 1.04%, the Young's modulus is 17.52 GPa, and the toughness is 0.10 MJ / m 3 。

[0089] (3) Preparation of a photo-thermal-electric generator:

[0090] The photo-thermal-electric generator consists of: a spent grain-based thermosetting material, a hot spot module, and a cooling module. The cooling module has three temperature cooling modes, namely cooling to 0 °C, 10 °C, and 25 °C. Select the temperature cooling mode according to the environment, and then place the assembled photo-thermal-electric generator under simulated sunlight irradiation (simulated sunlight is 100 mW / cm 2 ) Record its output voltage and current. The maximum output voltage is 299.13 mV, and the output current is 48.69 mA.

[0091] In the tenth embodiment of the present application:

[0092] (1) In-situ oxidation of spent grains:

[0093] Add 10 g of spent grain powder DG and 18 g of sodium periodate NaIO4 to 400 ml of deionized water. React the mixture in the dark at 50 °C for 10 h. After the reaction, wash the product with deionized water at least 3 times to remove unreacted sodium periodate and sodium iodide reduction by-products. Then dry the washed material at 35 °C to obtain oxidized spent grains ODG.

[0094] (2) Preparation of spent grain-based thermosetting material:

[0095] The oxidized spent grains ODG was hot-pressed at 110 °C and a pressure of 5 MPa for 2 hours to prepare a thermosetting material ODGT with a thickness of 0.75 mm. The tensile fracture strength of the obtained material was 19.13 MPa, the elongation at break was 1.05%, the Young's modulus was 20.43 GPa, and the toughness was 0.11 MJ / m 3 .

[0096] (3) Preparation of the photo-thermal-electric generator:

[0097] The photo-thermal-electric generator consists of: spent grains-based thermosetting material, hot spot module, and cooling module. Among them, the cooling module has three temperature cooling modes, which are cooling to 0 °C, 10 °C, and 25 °C respectively. The temperature cooling mode is selected according to the environment, and then the assembled photo-thermal-electric generator is placed under simulated sunlight irradiation (simulated sunlight is 100 mW / cm 2 ), and its output voltage and current are recorded. The highest output voltage is 311.44 mV, and the output current is 51.12 mA.

[0098] In summary, the present invention uses sodium periodate to selectively oxidize the active ingredients (i.e., cellulose and lignin) in the spent grains in situ, and realizes binder-free bonding through one-step hot pressing. During the process of selectively oxidizing the spent grains with sodium periodate in situ, a cross-linked network is formed at the interface of the spent grains through covalent bonds and hydrogen bonds. The prepared spent grains-based thermosetting material ODGT has excellent mechanical properties (such as mechanical properties, thermal stability, and solvent resistance). At the same time, by using the lignin units in the spent grains, the material is endowed with excellent photothermal conversion ability. Further, it is combined with a thermoelectric module and a cooling module to assemble a new type of photo-thermal-electric generator, which can supply power to electronic devices.

[0099] The above is only the implementation mode of the present invention. It should be understood that the present invention is not limited to the form disclosed herein, should not be regarded as an exclusion of other embodiments, but can be used in various other combinations, modifications, and environments, and can be changed within the scope of the concept described herein through the above teachings or the technology or knowledge in related fields. And any changes and modifications made by those skilled in the art without departing from the spirit and scope of the present invention should fall within the protection scope of the appended claims of the present invention.

Claims

1. Preparation of a spent grains-based thermosetting material, characterized in that: It includes the following steps: S1. Pour the spent grains into an aqueous solution of sodium periodate, heat and stir under dark conditions to generate oxidized spent grains, then wash with deionized water to remove unreacted sodium periodate, and put the remaining washed oxidized spent grains into an oven for drying; S2. Put the dried oxidized spent grains into a hot press and perform hot pressing to dry and form a spent-grain-based thermosetting material.

2. Preparation of the spent grains-based thermosetting material according to claim 1, characterized in that: Weigh 5-10 g of spent grains and pour them into an aqueous solution of sodium periodate. Heat and stir for 2-10 h under dark conditions to generate oxidized spent grains, then wash 3 times with deionized water to remove unreacted sodium periodate, and put the remaining washed oxidized spent grains into an oven for drying for 12 h; Put the dried oxidized spent grains into a hot press and perform hot pressing at a pressure of 2-5 MPa to dry and form a spent-grain-based thermosetting material.

3. The preparation of the spent grains-based thermosetting material according to claim 1 or 2, characterized in that: In step S1, the spent grains can be sorghum spent grains or corn spent grains.

4. The preparation of the spent grains-based thermosetting material according to claim 1 or 2, characterized in that: In step S1, the concentration of sodium periodate in the aqueous solution of sodium periodate is 45 mg / ml.

5. The preparation of the spent grains-based thermosetting material according to claim 4, characterized in that: The mass ratio of the spent grains to sodium periodate is 5:9 or 5:

18.

6. The preparation of the spent grains-based thermosetting material according to claim 1 or 2, characterized in that: In step S1, the heating and stirring temperature is 50°C.

7. The preparation of the spent grains-based thermosetting material according to claim 1 or 2, characterized in that: In step S1, the drying temperature in the oven is 105°C.

8. The preparation of the spent grains-based thermosetting material according to claim 1 or 2, characterized in that: In step S2, the hot pressing temperature of the hot press is 100-110°C, and the hot pressing time is 0.5-2 h.

9. Application of spent grains-based thermosetting material in a photo-thermoelectric generator, characterized in that: The photo-thermo-electric generator is composed of a spent-grain-based thermosetting material, a thermoelectric module and a cooling module, wherein the spent-grain-based thermosetting material is the spent-grain-based thermosetting material described in claim 1 or claim 2.

10. Use of the spent grains-based thermosetting material according to claim 9 in a photovoltaic thermal generator, characterized in that: The thickness of the spent-grain-based thermosetting material is 0.5 mm - 1 mm.

Images