Preparation method of aviation kerosene

Abstract

The invention provides a preparation method of aviation kerosene, which comprises the following steps: a) sequentially carrying out V-MOF / H2O2 pretreatment, enzyme hydrolysis and fermentation on corncob biomass to obtain fermentation liquor rich in ethanol intermediates; and b) carrying out one-pot catalytic conversion on the fermentation liquor rich in the ethanol intermediate obtained in the step a) under the action of a Ce-SAPO34 / Ni-HBET composite catalyst to obtain the aviation kerosene. Compared with the prior art, the method for preparing the aviation kerosene from the corncob biomass, provided by the invention, has the advantages that the aim of directionally synthesizing the biological aviation kerosene from the corncob biomass is achieved by coupling the processes of biological fermentation and catalytic conversion, the efficiency of high-value utilization of biomass resources is improved, and good economic and environmental benefits are achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of organic synthesis, and more particularly to a method for preparing aviation kerosene. Background Art

[0002] Lignocellulosic biomass is a renewable, low-cost feedstock that can be used to produce a variety of biofuels and biochemicals (Pattnaik F, Tripathi S, Patra BR, Nanda S, Kumar V, Dalai AK, Catalytic conversion of lignocellulosic polysaccharides to commodity biochemicals: a review, Environ Chem Lett, 2021, 19, 4119-4136). Biochemical pathways are one of the most widely used technologies for producing biofuels and biochemicals, especially for the production of bioethanol, biobutanol, and biosyngas (Liu Y, Tang Y, Gao H, Zhang W, Jiang Y, Xin F, Challenges and future perspectives of promising biotechnologies for lignocellulosic biorefinery, Molecules 2021, 26, 5411). Studies have shown that lignocellulose-based low-carbon alcohols produced by enzymatic hydrolysis and fermentation of lignocellulose waste can be used as intermediates for the production of biofuels or high-value-added chemicals (Reference: Zhang R, He Y, Luo Y, Lou D, Zhu R, Zhu C et al., Selective preparation of jet fuels from low carbon alcohols and ABE at atmospheric pressure, Energy 2023, 281, 128246).

[0003] Due to the unique composition and structure of lignocellulosic biomass, it has high resistance to biochemical conversion. Therefore, biomass pretreatment is considered a necessary and important initial step in the biorefinery process (Literature: Meng X, Wang Y, Conte AJ, Zhang S, Ryu J, Wie JJ, Applications of biomass-derived solvents in biomass pretreatment - Strategies, challenges, and prospects, Bioresour Technol, 2023, 368, 128280). Research has shown that the pretreatment of lignocellulosic biomass can break the recalcitrance of the lignocellulosic matrix, promote the separation of polysaccharides and lignin, and thus improve the accessibility of cellulase in enzymatic hydrolysis. To date, various biomass pretreatment methods have been used in the biorefinery process, which can be roughly divided into physical pretreatment, chemical pretreatment, and biological pretreatment (Literature: Guo Y, Liu Y, Guan M, Tang H, Wang Z, Lin L, Production of butanol from lignocellulosic biomass: recent advances, challenges, and prospects, RSC Adv, 2022, 12, 18848 - 18863). Among these biomass pretreatment methods, alkaline hydrogen peroxide (AHP) pretreatment has received increasing attention in recent years (Literature: Lee SH, Seah GX, Yang KL, A catalytic alkaline hydrogen peroxide (cAHP) pretreatment method for corn stover and optimization, Biomass Convers Bior, 2023, 13, 4767 - 4775). Alkaline hydrogen peroxide pretreatment can promote the delignification of lignocellulosic biomass and improve the accessibility of cellulase in enzymatic hydrolysis. However, the alkaline hydrogen peroxide pretreatment process usually needs to be carried out in a strongly alkaline environment, which may cause harm to the environment. Therefore, the development of green and efficient biomass pretreatment methods remains one of the bottleneck problems to be solved in the biorefinery process.

[0004] Aviation kerosene is one of the petroleum products, mainly composed of hydrocarbon compounds in specific fractions. For safety reasons, aviation fuels must meet very strict technical performance indicators. Therefore, low-carbon alcohols obtained by cellulose fermentation (such as bioethanol and biobutanol) cannot be directly used as aviation fuels or mixed with conventional aviation fuels (Literature: Díaz Pérez M A, Serrano Ruiz J C, Catalytic production of jet fuels from biomass, Molecules, 2020, 25, 802). Therefore, it is necessary to use the cellulose fermentation products as an intermediate and further catalytically convert them into hydrocarbon fuels that meet the requirements of aviation kerosene.

[0005] Since the reaction pathways and intermediates in the catalytic conversion of lignocellulose are often complex, to date, the directional synthesis of aviation fuels from lignocellulose remains a challenging scientific and technological problem. The key scientific and technological problems to be solved mainly include: improving the selectivity and yield of lignocellulose synthesis of aviation fuels through biomass enzymatic hydrolysis fermentation and catalyst optimization design. Summary of the Invention

[0006] In view of this, the purpose of the present invention is to provide a method for jointly pretreating corn cobs with V-MOF / H2O2 and catalytically synthesizing aviation kerosene. This method improves the efficiency of corn cob fermentation and aviation kerosene synthesis and has a high yield of aviation kerosene.

[0007] The present invention provides a method for preparing aviation kerosene, including the following steps:

[0008] a) Subjecting corn cob biomass to V-MOF / H2O2 pretreatment, enzymatic hydrolysis, and fermentation in sequence to obtain a fermentation broth rich in ethanol intermediates;

[0009] b) Carrying out one-pot catalytic conversion on the fermentation broth rich in ethanol intermediates obtained in step a) under the action of a Ce-SAPO34 / Ni-HBET composite catalyst to obtain aviation kerosene.

[0010] Preferably, the corn cob biomass in step a) includes:

[0011] Cellulose 40 wt% - 45 wt%;

[0012] Hemicellulose 35 wt% - 40 wt%;

[0013] Lignin 12 wt% - 15 wt%;

[0014] The rest.

[0015] Preferably, in the V-MOF / H2O2 pretreatment solution used in step a), the V-MOF / H2O2 pretreatment solution contains 100 ppm to 1000 ppm of V-MOF component and 1% to 10% of H2O2 component.

[0016] Preferably, step a) is specifically:

[0017] The corncob biomass is pretreated with a V-MOF / H2O2 pretreatment solution at 20°C to 30°C and pH = 6 to 7 to obtain pretreated corncob; then the pretreated corncob is subjected to an enzymatic hydrolysis reaction using cellulase to obtain a corncob enzymatic hydrolysate; finally, the corncob enzymatic hydrolysate is subjected to microbial fermentation using yeast to obtain a fermentation broth rich in ethanol intermediates.

[0018] Preferably, the temperature of the enzymatic hydrolysis reaction is 40°C to 60°C, and the pH value is 4.5 to 5.

[0019] Preferably, the temperature of the microbial fermentation is 20°C to 40°C, and the pH value is 5 to 6.

[0020] Preferably, in the Ce-SAPO34 / Ni-HBET composite catalyst in step b), it contains 1% to 5% of Ce-SAPO34 component and 2% to 10% of Ni-HBET component; the mass ratio of the 1% to 5% Ce-SAPO34 component to the 2% to 10% Ni-HBET component is 1:(1.5 to 3).

[0021] Preferably, the mass ratio of the fermentation broth rich in ethanol intermediates to the Ce-SAPO34 / Ni-HBET composite catalyst in step b) is (5 to 15):1.

[0022] Preferably, the reaction temperature of the one-pot catalytic conversion in step b) is 200°C to 220°C, the reaction pressure is 4 MPa to 6 MPa, and the reaction time is 4 h to 6 h.

[0023] Preferably, the conversion rate of the fermentation broth rich in ethanol intermediates reaches up to 95.9%, and the yield of the aviation kerosene reaches up to 68.0%.

[0024] The present invention provides a method for preparing aviation kerosene, comprising the following steps: a) subjecting corncob biomass to V-MOF / H2O2 pretreatment, enzymatic hydrolysis and fermentation in sequence to obtain a fermentation broth rich in ethanol intermediates; b) subjecting the fermentation broth rich in ethanol intermediates obtained in step a) to one-pot catalytic conversion under the action of a Ce-SAPO34 / Ni-HBET composite catalyst to obtain aviation kerosene. Compared with the prior art, the present invention provides a method for preparing aviation kerosene from corncob biomass. Through the coupling of the processes of biological fermentation and catalytic conversion, the goal of the directional synthesis of bio-aviation kerosene from corncob biomass is achieved, the efficiency of the high-value utilization of biomass resources is improved, and good economic and environmental benefits are obtained.

[0025] Meanwhile, the preparation method provided by the present invention has a simple process, mild and easy-to-control conditions, is easy to scale up and promote, and has broad practical application prospects in the field of preparing biofuels mainly composed of aviation kerosene. Detailed Embodiments

[0026] The technical solutions of 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, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without any creative work shall fall within the protection scope of the present invention.

[0027] The present invention provides a method for preparing aviation kerosene, comprising the following steps:

[0028] a) subjecting corncob biomass to V-MOF / H2O2 pretreatment, enzymatic hydrolysis and fermentation in sequence to obtain a fermentation broth rich in ethanol intermediates;

[0029] b) subjecting the fermentation broth rich in ethanol intermediates obtained in step a) to one-pot catalytic conversion under the action of a Ce-SAPO34 / Ni-HBET composite catalyst to obtain aviation kerosene.

[0030] The present invention first subjects corncob biomass to V-MOF / H2O2 pretreatment, enzymatic hydrolysis and fermentation in sequence to obtain a fermentation broth rich in ethanol intermediates.

[0031] In the present invention, the corncob biomass preferably comprises:

[0032] cellulose 40 wt% - 45 wt%;

[0033] hemicellulose 35 wt% - 40 wt%;

[0034] lignin 12 wt% - 15 wt%;

[0035] the remaining amount (inevitable impurities, etc.).

[0036] More preferably, it is composed of cellulose (40 wt% - 45 wt%), hemicellulose (35 wt% - 40 wt%) and lignin (12 wt% - 15 wt%). There are no special restrictions on the source of the corn cob biomass in the present invention, and commercially available products well-known to those skilled in the art can be used; in a preferred embodiment of the present invention, the corn cob raw material of the corn cob biomass is purchased from the corn cob waste of Guangxi Qiumingshan Agricultural Development Co., Ltd. (Nanning, China). This corn cob waste belongs to lignocellulosic raw materials and has the characteristics of high carbohydrate content, low cost and rich resources.

[0037] In the present invention, the particle size of the ground corn cob biomass is preferably 0.2 mm - 1.0 mm, and more preferably 0.2 mm - 0.5 mm.

[0038] In the present invention, the V-MOF / H2O2 pretreatment preferably uses a V-MOF / H2O2 pretreatment solution; in the V-MOF / H2O2 pretreatment solution, it preferably contains 100 ppm - 1000 ppm of the V-MOF component (vanadium-based metal-organic framework) and 1% - 10% of the H2O2 component (aqueous solution of hydrogen peroxide), and more preferably contains 400 ppm - 600 ppm of the V-MOF component and 4% - 6% of the H2O2 component (here, "%" represents mass percentage, that is, an aqueous solution of 4 wt% - 6 wt% H2O2).

[0039] In a preferred embodiment of the present invention, the V-MOF component is preferably obtained by a hydrothermal synthesis method, and can be specifically prepared according to the following steps:

[0040] a) Prepare a mixed solution A, add 2 mmol of 1,3,5-benzenetricarboxylic acid (H3BTC) to 25 mL of an aqueous solution of dimethylformamide (DNF), and stir for 30 minutes;

[0041] b) Prepare a mixed solution B, add 4 mmol of vanadium trichloride (VCl3) to 25 mL of an aqueous solution of dimethylformamide (DNF), and stir for 30 minutes;

[0042] c) Slowly drop the prepared solution A into solution B, stir for 1 hour to obtain a mixed solution AB;

[0043] d) Load the mixed solution AB into an autoclave and react at a temperature of 180 °C for 24 hours;

[0044] e) Filter, wash the precipitate formed in the autoclave by suction, and dry it at 80 °C to obtain the V-MOF component;

[0045] f) The pore diameter of the V-MOF component material prepared by the above method is about 8.5 nm, the specific surface area is 1400 m 2 / g, and the pore volume is 0.67 cm 3 / g.

[0046] The present invention uses corncob biomass as a raw material. The corncob biomass undergoes biological refining processes such as V-MOF / H2O2 pretreatment, enzymatic hydrolysis, and fermentation to obtain a fermentation broth rich in ethanol intermediates, which can be specifically obtained according to the following steps:

[0047] The corncob biomass is pretreated with a V-MOF / H2O2 pretreatment solution at 20°C to 30°C and pH = 6 to 7 to obtain pretreated corncobs; then the pretreated corncobs are subjected to enzymatic hydrolysis reaction using cellulase to obtain a corncob enzymatic hydrolysate; finally, the corncob enzymatic hydrolysate is subjected to microbial fermentation using yeast to obtain a fermentation broth rich in ethanol intermediates;

[0048] Preferably specifically:

[0049] The corncob biomass is pretreated with a V-MOF / H2O2 pretreatment solution at room temperature and pH = 6.5 to obtain pretreated corncobs; then the pretreated corncobs are subjected to enzymatic hydrolysis reaction using cellulase to obtain a corncob enzymatic hydrolysate; finally, the corncob enzymatic hydrolysate is subjected to microbial fermentation using yeast (conventional yeast) to obtain a fermentation broth rich in ethanol intermediates.

[0050] In the present invention, the corncob raw material is stirred and pretreated in a V-MOF / H2O2 pretreatment solution for 0.5 h to 1.5 h. After pretreatment, the corncobs are washed and dried for subsequent enzymatic hydrolysis process.

[0051] In the present invention, the temperature of the enzymatic hydrolysis reaction is preferably 40°C to 60°C, more preferably 50°C, and the pH value is preferably 4.5 to 5, more preferably 4.8; the temperature of the microbial fermentation is preferably 20°C to 40°C, more preferably 30°C, and the pH value is preferably 5 to 6, more preferably 5.5.

[0052] In a preferred embodiment of the present invention, the corncob enzymatic hydrolysis conditions include: the dosage of cellulase is about 50 FPU per gram of corncob, 10 g of corncob is added to 100 mL of enzymatic hydrolysate, the enzymatic hydrolysis temperature is 50°C, the pH value is 4.8, and the enzymatic hydrolysis time is 72 h; the obtained corncob enzymatic hydrolysate is centrifuged at 5000 r / min for 10 min to remove the precipitate, and the pH value is adjusted to 5.5 using ammonia water for subsequent fermentation process.

[0053] In a preferred embodiment of the present invention, a fermentation broth rich in ethanol intermediates is prepared by fermenting corn cob hydrolysate using yeast (CICC1301); the fermentation conditions of the corn cob hydrolysate include: a fermentation temperature of 30°C, a pH value of 5.5, and a fermentation time of 96 hours; the fermentation can be carried out according to the following operating steps: (1) the yeast is inoculated and cultured in a seed culture at 30°C for 48 hours, wherein the inoculation culture medium contains 40 g / L glucose, 10 g / L yeast extract, and 20 g / L peptone; (2) a fermentation medium (based on 100 mL) is prepared using corn cob hydrolysate (10 mL) as a carbon source, wherein the fermentation medium also includes a seed culture (5 mL), 10 g / L yeast extract, and 20 g / L peptone; (3) the fermentation broth is heated at 30°C, pH value 5.5, and fermentation time 96 hours. 5.5 and anaerobic conditions, the corn cob hydrolysate was fermented using a fermentation medium containing yeast (100 mL) for 96 h; (4) after the fermentation was completed, the obtained fermentation liquid was centrifuged at a speed of 5000 r / min for 10 min, and the obtained fermentation liquid rich in ethanol intermediates was used for the subsequent synthesis of bio-jet fuel.

[0054] In a preferred embodiment of the present invention, the cellulase (CAS-9012548) used in the corncob enzymatic hydrolysis process was purchased from Ningxia Heshibi Biotechnology Co., Ltd. (Yinchuan, China); the yeast (CICC1301) used in the fermentation process of the corncob hydrolysate was purchased from the China Industrial Microorganism Culture Collection Center (Beijing, China).

[0055] After obtaining the fermentation liquid rich in ethanol intermediates, the present invention performs a one-pot catalytic conversion on the obtained fermentation liquid rich in ethanol intermediates under the action of a Ce-SAPO34 / Ni-HBET composite catalyst to obtain aviation kerosene.

[0056] In the present invention, the Ce-SAPO34 / Ni-HBET composite catalyst preferably contains 1% to 5% Ce-SAPO34 component and 2% to 10% Ni-HBET component; the mass ratio of the 1% to 5% Ce-SAPO34 component to the 2% to 10% Ni-HBET component is preferably 1:(1.5 to 3), more preferably 1:2.

[0057] In the present invention, the Ce-SAPO34 / Ni-HBET composite catalyst more preferably comprises 3% Ce-SAPO34 component and 5% Ni-HBET component.

[0058] The present invention utilizes fermentation broth rich in ethanol intermediates as raw material, adopts Ce-SAPO34 / Ni-HBET composite catalyst, and adopts a one-pot reaction mode design of catalytic dehydration, olefin polymerization and hydrogenation saturation. The fermentation broth rich in ethanol intermediates can be catalytically converted into bio-jet fuel in one step in the same reactor.

[0059] In the present invention, in the Ce-SAPO34 / Ni-HBET composite catalyst, the Ce content of the Ce-SAPO34 component is preferably 1.0 wt% to 5.0 wt%, more preferably 3.0 wt%, and specifically can be 1.0 wt%, 2.0 wt%, 3.0 wt%, 4.0 wt%, 5.0 wt%.

[0060] In a preferred embodiment of the present invention, the Ce-SAPO34 component in the Ce-SAPO34 / Ni-HBET composite catalyst is obtained by a hydrothermal synthesis method, and specifically can be prepared according to the following steps:

[0061] a) Add the SAPO34 molecular sieve to an aqueous solution containing cerium nitrate. The dosage ratio of the SAPO34 and cerium nitrate is determined according to the cerium content in the finally prepared composite catalyst and is not separately limited. Then add ammonia water to the above mixed solution to adjust the pH value to 9, and stir at room temperature for 5 hours;

[0062] b) React the above mixed solution in a stainless steel autoclave at 200 °C for 24 h;

[0063] c) Wash the reaction product precipitate, dry it at 100 °C for 12 h, and sinter the dried precipitate at 600 °C for 5 h to obtain the Ce-SAPO34 component powder;

[0064] d) The pore diameter of the Ce-SAPO34 component material prepared by the above method is 2.0 nm to 3.0 nm, the specific surface area is 500 m 2 / g to 600 m 2 / g, and the pore volume is 0.1 cm 3 / g to 0.2 cm 3 / g.

[0065] In the present invention, the Ni content of the Ni-HBET component in the composite catalyst is preferably 1 wt% to 10 wt%, more preferably 5.0 wt%, and specifically can be 1.0 wt%, 2.0 wt%, 3.0 wt%, 4.0 wt%, 5.0 wt%, 6.0 wt%, 7.0 wt%, 8.0 wt%, 9.0 wt%, 10.0 wt%.

[0066] In a preferred embodiment of the present invention, the Ni-HBET component in the composite catalyst is obtained by a hydrothermal synthesis method, and specifically can be prepared according to the following steps:

[0067] a) adding HBET molecular sieves to an aqueous solution comprising nickel nitrate, wherein the usage ratio of the HBET and nickel nitrate is determined according to the nickel content in the final composite catalyst to be prepared and is no longer limited separately, and then adding ammoniacal liquor to the above-mentioned mixed solution, adjusting the pH value to 9, and stirring at room temperature for 5 hours;

[0068] b) reacting the mixed solution at 200° C. in a stainless steel autoclave for 24 h;

[0069] c) washing the precipitate after the reaction, drying it at 100° C. for 12 h, and sintering the dried precipitate at 600° C. for 5 h to obtain a Ni-HBET component powder;

[0070] d) The pore size of the Ni-HBET component material prepared by the above method is 5.0nm to 8.0nm, and the specific surface area is 380m 2 / g~500m 2 / g, pore volume 0.16cm 3 / g~0.19cm 3 / g.

[0071] In the present invention, the reactant is derived from a fermentation broth rich in ethanol intermediates obtained by pretreatment of corn cob biomass with a V-MOF / H2O2 solution, enzymatic hydrolysis and fermentation; the mass ratio of the fermentation broth rich in ethanol intermediates to the Ce-SAPO34 / Ni-HBET composite catalyst is preferably (5-15):1, more preferably (9-11):1.

[0072] In the present invention, the reaction temperature of the one-pot catalytic conversion is preferably 200°C to 220°C, more preferably 210°C, the reaction pressure is preferably 4MPa to 6MPa, more preferably 5MPa, and the reaction time is preferably 4h to 6h, more preferably 5h.

[0073] In the present invention, a one-pot reaction mode design of catalytic dehydration, olefin polymerization and hydrogenation saturation is adopted for the directional preparation of aviation kerosene from ethanol-rich intermediate fermentation liquid, that is, Ce-SAPO34 component is used to carry out selective catalytic dehydration reaction of ethanol-rich intermediate, and Ni-HBET component is used to carry out olefin polymerization and hydrogenation saturation reaction in the same reactor; the specific operation steps are as follows: (1) first filling Ce-SAPO34 component in the front section of a cylindrical fixed-bed reactor with the composite catalyst, and filling Ni-HBET component in the rear section of the cylindrical fixed-bed reactor with the composite catalyst; (2) using nitrogen or other inert gas to purge for 1 hour, and then switching to hydrogen to ensure that the catalytic bed reactor is at a set reaction pressure; (3) heating the reactor to a set temperature, and after the temperature is constant, opening the injection valve and injecting the ethanol-rich intermediate fermentation liquid using an injection pump; (4) carrying out a catalytic conversion reaction according to a set reaction time, and after the reaction is completed, the product is quantitatively analyzed by a chromatogram-mass spectrometer.

[0074] In the present invention, the conversion rate of the fermentation liquid rich in ethanol intermediates reaches up to 95.9%, and the yield of the aviation kerosene reaches up to 68.0%.

[0075] Compared with the prior art, the method provided by the present invention has at least the following advantages and beneficial technical effects: 1) The present invention integrates the processes of biorefining and catalytic conversion to provide a method for producing aviation kerosene by combining V-MOF / H2O2 corn cob pretreatment and catalytic synthesis. The corn cob is sequentially subjected to V-MOF / H2O2 corn cob pretreatment, enzymatic hydrolysis and fermentation to obtain a fermentation broth rich in ethanol intermediates. Under the action of a Ce-SAPO34 / Ni-HBET composite catalyst, the fermentation broth is subjected to catalytic dehydration, olefin polymerization and saturation in a one-pot reaction in the same reactor to obtain a biofuel mainly composed of bio-jet fuel; 2) The present invention promotes the enzymatic hydrolysis and fermentation process of the corn cob through V-MOF / H2O2 corn cob pretreatment, thereby increasing the yield of ethanol intermediates; 3) The present invention improves the selectivity and yield of bio-aviation fuel through the Ce-SAPO34 / Ni-HBET composite catalyst and catalytic conversion one-pot reaction design, effectively achieving the goal of directed synthesis of bio-aviation kerosene from biomass waste. Actual measurements show that the conversion rate of the fermentation broth rich in ethanol intermediates of the present invention can reach up to 95.9%, and the selectivity of aviation kerosene can reach up to 68.0%; 4) The method provided by the present invention is to directionally convert corn cob waste into high-value bio-jet fuel products through the coupling of biorefining and catalytic reaction processes, with the characteristics of mild reaction conditions, green process, process integration and high aviation kerosene yield; the present invention converts abundant, low-cost and renewable agricultural waste raw materials into high-value-added aviation fuel, realizes the high-value comprehensive utilization of biomass resources, and has good economic and environmental benefits.

[0076] The present invention provides a method for preparing aviation kerosene, comprising the following steps: a) subjecting corncob biomass to V-MOF / H2O2 pretreatment, enzymatic hydrolysis, and fermentation to obtain a fermentation broth rich in ethanol intermediates; and b) subjecting the fermentation broth rich in ethanol intermediates obtained in step a) to a one-pot catalytic conversion over a Ce-SAPO34 / Ni-HBET composite catalyst to obtain aviation kerosene. Compared to existing technologies, the present invention provides a method for producing aviation kerosene from corncob biomass. By coupling biofermentation with catalytic conversion, this method achieves the goal of synthesizing bio-aviation kerosene from corncob biomass, improves the efficiency of high-value utilization of biomass resources, and offers excellent economic and environmental benefits.

[0077] At the same time, the preparation method provided by the present invention has simple process, mild conditions, easy control, easy expansion and promotion, and has broad practical application prospects in the field of preparing biofuels with aviation kerosene as the main component.

[0078] In order to further illustrate the present invention, the following examples are given below to provide a detailed description.

[0079] Example 1

[0080] In this example, corn cobs were used as biomass raw materials and the effect of converting the corn cobs into an ethanol-rich intermediate fermentation broth was investigated by sequentially subjecting the corn cobs to a biorefining process including 100 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation.

[0081] In this example, corncob raw materials were purchased from Guangxi Qiumingshan Agricultural Development Co., Ltd. (Nanning, China), and the particle size after grinding was 0.2-0.5 mm. Cellulase CAS-9012548 used in the corncob enzymatic hydrolysis process was purchased from Ningxia Heshibi Biotechnology Co., Ltd. (Yinchuan, China). Yeast CICC1301 used in the fermentation of corncob enzymatic hydrolysate was purchased from China Industrial Microorganism Culture Collection Center (Beijing, China).

[0082] In this embodiment, the V-MOF component is obtained by a hydrothermal synthesis method, which can be prepared by the following steps:

[0083] a) Prepare mixed solution A by adding 2 mmol of 1,3,5-benzenetricarboxylic acid (H3BTC) to 25 mL of dimethylformamide (DNF) aqueous solution and stirring for 30 minutes;

[0084] b) Prepare mixed solution B by adding 4 mmol of vanadium trichloride (VCl3) to 25 mL of dimethylformamide (DNF) aqueous solution and stirring for 30 minutes;

[0085] c) Slowly add the prepared Solution A dropwise to Solution B and stir for 1 hour to obtain a mixed solution AB;

[0086] d) Load the mixed solution AB into an autoclave and react at 180 °C for 24 hours;

[0087] e) Filter, wash the precipitate formed in the autoclave and dry it at 80 °C to obtain the V-MOF component;

[0088] f) The pore size of the V-MOF component material prepared by the above method is 8.5 nm, the specific surface area is 1400 m 2 / g, and the pore volume is 0.67 cm 3 / g.

[0089] In this example, corn cobs are subjected to biological refining processes such as 100 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation to be converted into a fermentation broth rich in ethanol intermediates, which can be specifically obtained according to the following steps:

[0090] a) First, pretreat the corn cob biomass with a 100 ppm V-MOF / 5% H2O2 solution. In this example, the conditions for corn cob pretreatment include: adding 10 g of corn cobs to 100 mL of the pretreatment solution, the pretreatment temperature is room temperature (25 °C), the pH value is 6.5, and the pretreatment time is 2 hours. The specific operation steps for corn cob pretreatment can be as follows: (1) Add 100 ppm V-MOF (0.1 g) and 5 g of H2O2 to 100 mL of deionized water to prepare a 100 ppm V-MOF / 5% H2O2 pretreatment solution (based on 100 mL); (2) Add 10 g of corn cobs to 100 mL of the pretreatment solution and stir and pretreat at room temperature for 2 hours; (3) After pretreatment, wash the solid corn cobs with water and dry them at 80 °C for 12 hours, and store them in a desiccator for subsequent enzymatic hydrolysis process.

[0091] b) Then, cellulase was used to carry out an enzymatic hydrolysis reaction on the pretreated corncobs. In this embodiment, the enzymatic hydrolysis conditions of the corncobs included: the dosage of cellulase was about 50 FPU (cellulase activity unit) per gram of corncobs, the dosage of corncobs was 10 g of corncobs added to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature was 50 °C, the pH value was 4.8, and the enzymatic hydrolysis time was 72 hours. Specifically, the enzymatic hydrolysis of corncobs could be carried out according to the following operation steps: (1) Prepare an enzymatic hydrolysis solution by adding cellulase to a sodium citrate buffer solution (0.03 M), and the addition amount of cellulase was about 50 FPU per gram of corncobs; (2) Add the pretreated corncobs to 100 mL of the enzymatic hydrolysis solution and carry out an enzymatic hydrolysis reaction at 50 °C and pH 4.8 for 72 hours; (3) Centrifuge the obtained corncob enzymatic hydrolysis solution at a speed of 5000 r / min for 10 minutes to remove the precipitate; (4) Adjust the pH value to 5.5 with ammonia water and store it in a refrigerator at 4 °C for subsequent fermentation process.

[0092] c) Finally, yeast (CICC1301) was used to ferment the corncob enzymatic hydrolysis solution to prepare a fermentation broth rich in ethanol intermediates. The fermentation conditions of the corncob enzymatic hydrolysis solution included: the fermentation temperature was 30 °C, the pH value was 5.5, and the fermentation time was 96 hours. Specifically, the fermentation could be carried out according to the following operation steps: (1) Inoculate and culture yeast in a seed culture at 30 °C for 48 hours, and the inoculation medium contained 40 g / L glucose, 10 g / L yeast extract, and 20 g / L peptone; (2) Use the corncob hydrolysate (10 mL) as a carbon source to prepare a fermentation medium (based on 100 mL), and the fermentation medium also included a seed culture (5 mL), 10 g / L yeast extract, and 20 g / L peptone; (3) Under the conditions of 30 °C, pH 5.5, and anaerobic conditions, ferment the corncob enzymatic hydrolysis solution with the yeast-containing fermentation medium for 96 hours; (4) After fermentation, centrifuge the obtained fermentation broth at a speed of 5000 r / min for 10 minutes to obtain a fermentation broth rich in ethanol intermediates, and store it at 4 °C for subsequent synthesis of bio-aviation kerosene.

[0093] In this embodiment, the fermentation products were quantitatively analyzed by a chromatograph-mass spectrometer and high performance liquid chromatography. The effects of using corncobs to prepare a fermentation broth rich in ethanol intermediates through sequential 100 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefining processes are shown in Table 1 in detail. The ethanol yield was 27.9%, and the ethanol concentration was 31.7 g / L.

[0094] Example 2

[0095] In this embodiment, the effects of using corncob biomass as a raw material and sequentially subjecting corncobs to 200 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation and other biorefining processes to convert them into a fermentation broth rich in ethanol intermediates were investigated.

[0096] In this example, the corncob raw material used, the cellulase used in the enzymatic hydrolysis process, and the yeast used in the fermentation process are the same as those in Example 1.

[0097] In this example, the V-MOF component in the corncob pretreatment process is obtained by a hydrothermal synthesis method, and the specific synthesis steps are the same as those in Example 1.

[0098] In this example, the corncob is subjected to biological refining processes such as 200 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation to be converted into a fermentation broth rich in ethanol intermediates, which can be specifically obtained according to the following steps:

[0099] a) First, the corncob biomass is pretreated with a 200 ppm V-MOF / 5% H2O2 solution. In this example, the conditions for corncob pretreatment include: adding 10 g of corncob to 100 mL of the pretreatment solution, the pretreatment temperature is room temperature (25 °C), the pH value is 6.5, and the pretreatment time is 2 hours. The specific operation steps for corncob pretreatment can be as follows: (1) Add 200 ppm of V-MOF (0.2 g) and 5 g of H2O2 to 100 mL of deionized water to prepare a 200 ppm V-MOF / 5% H2O2 pretreatment solution (based on 100 mL); (2) Add 10 g of corncob to 100 mL of the pretreatment solution and stir (or soak) at room temperature for 2 hours for pretreatment; (3) After pretreatment, the solid corncob is washed with water and dried at 80 °C for 12 hours, and stored in a desiccator for subsequent enzymatic hydrolysis process.

[0100] b) Then, the pretreated corncob is subjected to an enzymatic hydrolysis reaction using cellulase. In this example, the preparation method and operation steps of the enzymatic hydrolysis solution are the same as those in Example 1. The conditions for enzymatic hydrolysis of the pretreated corncob include: the cellulase dosage is about 50 FPU per gram of corncob, 10 g of corncob is added to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature is 50 °C, the pH value is 4.8, and the enzymatic hydrolysis time is 72 hours.

[0101] c) Finally, the corncob enzymatic hydrolysis solution is fermented using yeast under anaerobic conditions to prepare a fermentation broth rich in ethanol intermediates. In this example, the preparation method and operation steps of the fermentation medium are the same as those in Example 1. The fermentation conditions for the corncob enzymatic hydrolysis solution include: adding 5 mL of the seed medium to 100 mL of the fermentation medium, the fermentation temperature is 30 °C, the pH value is 5.5, and the fermentation time is 96 hours.

[0102] In this example, the fermentation products were quantitatively analyzed by chromatography-mass spectrometry and high performance liquid chromatography. The effects of using corncob to prepare fermentation broth rich in ethanol intermediates through sequential 200 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefining processes are shown in Table 1. The ethanol yield was 31.0% and the ethanol concentration was 34.7 g / L.

[0103] Example 3

[0104] In this example, the effects of using corncob biomass as raw material to convert corncob into fermentation broth rich in ethanol intermediates through sequential 300 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefining processes were investigated.

[0105] In this example, the corncob raw material used, the cellulase used in the enzymatic hydrolysis process, and the yeast used in the fermentation process were the same as those in Example 1.

[0106] In this example, the V-MOF component in the corncob pretreatment process was obtained by a hydrothermal synthesis method, and the specific synthesis steps were the same as those in Example 1.

[0107] In this example, the corncob was converted into fermentation broth rich in ethanol intermediates through sequential 300 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefining processes, and the specific steps were as follows:

[0108] a) First, the corncob biomass was pretreated with 300 ppm V-MOF / 5% H2O2 solution. In this example, the conditions for corncob pretreatment included: adding 10 g of corncob to 100 mL of pretreatment solution, the pretreatment temperature was room temperature (25 °C), the pH value was 6.5, and the pretreatment time was 2 hours. The specific operation steps for corncob pretreatment were as follows: (1) Add 300 ppm of V-MOF (0.3 g) and 5 g of H2O2 to 100 mL of deionized water to prepare 300 ppm V-MOF / 5% H2O2 pretreatment solution (based on 100 mL); (2) Add 10 g of corncob to 100 mL of pretreatment solution and stir for 2 hours at room temperature; (3) After pretreatment, the solid corncob was washed with water and dried at 80 °C for 12 hours, and stored in a desiccator for subsequent enzymatic hydrolysis process.

[0109] b) Then, cellulase is used to carry out an enzymatic hydrolysis reaction on the pretreated corncobs. In this embodiment, the preparation method and operation steps of the enzymatic hydrolysis solution are the same as those in Example 1. The enzymatic hydrolysis conditions for the pretreated corncobs include: the dosage of cellulase is about 50 FPU per gram of corncobs, 10 g of corncobs are added to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature is 50 °C, the pH value is 4.8, and the enzymatic hydrolysis time is 72 hours.

[0110] c) Finally, yeast is used to ferment the corncob enzymatic hydrolysis solution under anaerobic conditions to prepare a fermentation broth rich in ethanol intermediates. In this embodiment, the preparation method and operation steps of the fermentation medium are the same as those in Example 1. The fermentation conditions for the corncob enzymatic hydrolysis solution include: 5 ml of the seed medium is added to 100 mL of the fermentation medium, the fermentation temperature is 30 °C, the pH value is 5.5, and the fermentation time is 96 hours.

[0111] In this embodiment, the fermentation products are quantitatively analyzed by a chromatograph-mass spectrometer and high performance liquid chromatography. The effects of using corncobs to sequentially undergo 300 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefinery processes to prepare a fermentation broth rich in ethanol intermediates are shown in Table 1 in detail. The ethanol yield obtained is 33.4%, and the ethanol concentration is 38.5 g / L.

[0112] Example 4

[0113] In this embodiment, the effects of using corncob biomass as a raw material and subjecting corncobs to a series of biorefinery processes such as 500 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation to convert them into a fermentation broth rich in ethanol intermediates are investigated.

[0114] In this embodiment, the corncob raw materials used, the cellulase used in the enzymatic hydrolysis process, and the yeast used in the fermentation process are the same as those in Example 1.

[0115] In this embodiment, the V-MOF component in the corncob pretreatment process is obtained by a hydrothermal synthesis method, and the specific synthesis steps are the same as those in Example 1.

[0116] In this embodiment, the corncobs are subjected to a series of biorefinery processes such as 500 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation to be converted into a fermentation broth rich in ethanol intermediates, and the specific steps can be obtained as follows:

[0117] a) First, pretreat the corncob biomass with a 500 ppm V-MOF / 5% H2O2 solution. In this example, the conditions for corncob pretreatment include: adding 10 g of corncob to 100 mL of the pretreatment solution, with a pretreatment temperature of room temperature (25 °C), a pH value of 6.5, and a pretreatment time of 2 hours. The corncob pretreatment can be specifically carried out according to the following operating steps: (1) Add 500 ppm of V-MOF (0.5 g) and 5 g of H2O2 to 100 mL of deionized water to prepare a 500 ppm V-MOF / 5% H2O2 pretreatment solution (based on 100 mL); (2) Add 10 g of corncob to 100 mL of the pretreatment solution and stir (or soak) for pretreatment at room temperature for 2 hours; (3) After pretreatment, the solid corncob is washed with water and dried at 80 °C for 12 hours, and stored in a desiccator for subsequent enzymatic hydrolysis process.

[0118] b) Then, perform an enzymatic hydrolysis reaction on the pretreated corncob using cellulase. In this example, the preparation method and operating steps of the enzymatic hydrolysis solution are the same as those in Example 1. The enzymatic hydrolysis conditions for the pretreated corncob include: the cellulase dosage is about 50 FPU per gram of corncob, add 10 g of corncob to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature is 50 °C, the pH value is 4.8, and the enzymatic hydrolysis time is 72 hours.

[0119] c) Finally, ferment the corncob enzymatic hydrolysis solution using yeast under anaerobic conditions to prepare a fermentation broth rich in ethanol intermediates. In this example, the preparation method and operating steps of the fermentation medium are the same as those in Example 1. The fermentation conditions for the corncob enzymatic hydrolysis solution include: add 5 mL of the seed medium to 100 mL of the fermentation medium, the fermentation temperature is 30 °C, the pH value is 5.5, and the fermentation time is 96 hours.

[0120] In this example, the fermentation products are quantitatively analyzed by chromatography-mass spectrometry and high-performance liquid chromatography. The effects of using corncob to prepare a fermentation broth rich in ethanol intermediates through sequential 500 ppm V-MOF / 5% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefining processes are shown in Table 1 in detail. The ethanol yield is 35.2%, and the ethanol concentration is 40.9 g / L.

[0121] Example 5

[0122] In this example, the effects of using corncob biomass as a raw material to convert corncob into a fermentation broth rich in ethanol intermediates through sequential 1000 ppm V-MOF / 10% H2O2 pretreatment, enzymatic hydrolysis, fermentation, and other biorefining processes were investigated.

[0123] In this example, the corncob raw material used, the cellulase used in the enzymatic hydrolysis process, and the yeast used in the fermentation process are the same as those in Example 1.

[0124] In this example, the V-MOF component in the corncob pretreatment process is obtained by a hydrothermal synthesis method, and the specific synthesis steps are the same as those in Example 1.

[0125] In this example, the corncob is subjected to biological refining processes such as 1000 ppm V-MOF / 10% H2O2 pretreatment, enzymatic hydrolysis, and fermentation to be converted into a fermentation broth rich in ethanol intermediates, and specifically can be obtained according to the following steps:

[0126] a) First, the corncob biomass is pretreated with a 1000 ppm V-MOF / 10% H2O2 solution. In this example, the conditions for corncob pretreatment include: adding 10 g of corncob to 100 mL of the pretreatment solution, the pretreatment temperature is room temperature (25 °C), the pH value is 6.5, and the pretreatment time is 2 hours. The specific operation steps for corncob pretreatment can be as follows: (1) Add 1000 ppm of V-MOF (1.0 g) and 5 g of H2O2 to 100 mL of deionized water to prepare a 1000 ppm V-MOF / 10% H2O2 pretreatment solution (based on 100 mL); (2) Add 10 g of corncob to 100 mL of the pretreatment solution and stir for 2 hours at room temperature for pretreatment; (3) After pretreatment, the solid corncob is washed with water and dried at 80 °C for 12 hours and stored in a desiccator for subsequent enzymatic hydrolysis process.

[0127] b) Then, the pretreated corncob is subjected to an enzymatic hydrolysis reaction using cellulase. In this example, the preparation method and operation steps of the enzymatic hydrolysis solution are the same as those in Example 1. The enzymatic hydrolysis conditions for the pretreated corncob include: the cellulase dosage is about 50 FPU per gram of corncob, add 10 g of corncob to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature is 50 °C, the pH value is 4.8, and the enzymatic hydrolysis time is 72 hours.

[0128] c) Finally, the corncob enzymatic hydrolysis solution is fermented using yeast under anaerobic conditions to prepare a fermentation broth rich in ethanol intermediates. In this example, the preparation method and operation steps of the fermentation medium are the same as those in Example 1. The fermentation conditions for the corncob enzymatic hydrolysis solution include: adding 5 ml of the seed medium to 100 mL of the fermentation medium, the fermentation temperature is 30 °C, the pH value is 5.5, and the fermentation time is 96 hours.

[0129] In this embodiment, the fermentation products were quantitatively analyzed by chromatography-mass spectrometry and high performance liquid chromatography. The effects of using corncobs to prepare ethanol intermediates through sequential 1000 ppm V-MOF / 10% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefinery processes are shown in Table 1 in detail. The ethanol yield obtained was 34.9%, and the ethanol concentration was 40.2 g / L.

[0130] Comparative Example 1

[0131] In this comparative example, the effects of using corncob biomass as a raw material and converting corncobs into a fermentation broth rich in ethanol intermediates through sequential hydrogen peroxide pretreatment, enzymatic hydrolysis, and fermentation biorefinery processes were investigated.

[0132] In this embodiment, the corncob raw material used, the cellulase used in the enzymatic hydrolysis process, and the yeast used in the fermentation process were the same as those in Example 1.

[0133] In this embodiment, the corncobs were converted into a fermentation broth rich in ethanol intermediates through sequential 10% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefinery processes, and the specific steps were as follows:

[0134] a) First, the corncob biomass was pretreated with a 10% H2O2 solution. In this embodiment, the conditions for corncob pretreatment included: adding 10 g of corncobs to 100 mL of the pretreatment solution, the pretreatment temperature was room temperature (25 °C), the pH value was 6.5, and the pretreatment time was 2 hours. The specific operation steps for corncob pretreatment were as follows: (1) Add 10 g of H2O2 to 100 mL of deionized water to prepare a 10% H2O2 pretreatment solution (based on 100 mL); (2) Add 10 g of corncobs to 100 mL of the pretreatment solution and stir for 2 hours at room temperature; (3) After pretreatment, the solid corncobs were washed with water and dried at 80 °C for 12 hours for subsequent enzymatic hydrolysis.

[0135] b) Then, the pretreated corncobs were subjected to an enzymatic hydrolysis reaction using cellulase. In this comparative example, the preparation method and operation steps of the enzymatic hydrolysis solution were the same as those in Example 1. The conditions for enzymatic hydrolysis of the pretreated corncobs included: the cellulase dosage was about 50 FPU per gram of corncobs, 10 g of corncobs were added to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature was 50 °C, the pH value was 4.8, and the enzymatic hydrolysis time was 72 hours.

[0136] c) Finally, ferment the corncob enzymatic hydrolysate under anaerobic conditions using yeast to prepare a fermentation broth rich in ethanol intermediates. In this comparative example, the preparation method and operating steps of the fermentation medium are the same as those in Example 1. The fermentation conditions for the corncob enzymatic hydrolysate include: adding 5 ml of seed medium to 100 mL of fermentation medium, a fermentation temperature of 30 °C, a pH value of 5.5, and a fermentation time of 96 hours.

[0137] In this comparative example, the fermentation products were quantitatively analyzed by gas chromatography-mass spectrometry and high performance liquid chromatography. The effects of using corncobs through 10% H2O2 pretreatment, enzymatic hydrolysis, and fermentation biorefinery processes to prepare fermentation broths rich in ethanol intermediates are shown in Table 1 in detail. The ethanol yield obtained was 24.6%, and the ethanol concentration was 28.2 g / L.

[0138] Comparative Example 2

[0139] In this comparative example, the effects of using corncob biomass as a raw material and converting it into a fermentation broth rich in ethanol intermediates through biorefinery processes such as 500 ppm V-MOF pretreatment, enzymatic hydrolysis, and fermentation of corncobs were investigated.

[0140] In this example, the corncob raw material used, the cellulase used in the enzymatic hydrolysis process, the yeast used in the fermentation process, and the V-MOF preparation method are the same as those in Example 1.

[0141] In this example, converting corncobs into a fermentation broth rich in ethanol intermediates through biorefinery processes such as 500 ppm V-MOF pretreatment, enzymatic hydrolysis, and fermentation can be specifically obtained according to the following steps:

[0142] a) First, pretreat the corncob biomass with a 500 ppm V-MOF solution. In this example, the conditions for corncob pretreatment include: adding 10 g of corncobs to 100 mL of pretreatment solution, a pretreatment temperature of room temperature (25 °C), a pH value of 6.5, and a pretreatment time of 2 hours. The specific operation steps for corncob pretreatment can be as follows: (1) Add 0.5 g of V-MOF to 100 mL of deionized water to prepare a 500 ppm V-MOF pretreatment solution (based on 100 mL); (2) Add 10 g of corncobs to 100 mL of pretreatment solution and stir and pretreat at room temperature for 2 hours; (3) After pretreatment, the solid corncobs are washed with water and dried at 80 °C for 12 hours for subsequent enzymatic hydrolysis process.

[0143] b) Then, cellulase was used to carry out an enzymatic hydrolysis reaction on the pretreated corncobs. In this comparative example, the preparation method and operation steps of the enzymatic hydrolysis solution were the same as those in Example 1. The enzymatic hydrolysis conditions of the pretreated corncobs included: the dosage of cellulase was about 50 FPU per gram of corncobs, 10 g of corncobs were added to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature was 50 °C, the pH value was 4.8, and the enzymatic hydrolysis time was 72 hours.

[0144] c) Finally, yeast was used to ferment the corncob enzymatic hydrolysis solution under anaerobic conditions to prepare a fermentation broth rich in ethanol intermediates. In this comparative example, the preparation method and operation steps of the fermentation medium were the same as those in Example 1. The fermentation conditions of the corncob enzymatic hydrolysis solution included: 5 mL of the seed medium was added to 100 mL of the fermentation medium, the fermentation temperature was 30 °C, the pH value was 5.5, and the fermentation time was 96 hours.

[0145] In this comparative example, the fermentation products were quantitatively analyzed by a chromatograph-mass spectrometer and high performance liquid chromatography. The effects of using corncobs to sequentially pass through 500 ppm V-MOF, enzymatic hydrolysis, and fermentation biorefinery processes to prepare a fermentation broth rich in ethanol intermediates are shown in Table 1 in detail. The ethanol yield obtained was 22.7%, and the ethanol concentration was 25.9 g / L.

[0146] Comparative Example 3

[0147] In this comparative example, the effects of using corncob biomass as a raw material to convert untreated corncobs into a fermentation broth rich in ethanol intermediates through sequential enzymatic hydrolysis and fermentation biorefinery processes were investigated.

[0148] In this comparative example, the corncob raw materials used, the cellulase used in the enzymatic hydrolysis process, and the yeast used in the fermentation process were the same as those in Example 1.

[0149] In this example, untreated corncobs were sequentially subjected to enzymatic hydrolysis and fermentation biorefinery processes to be converted into a fermentation broth rich in ethanol intermediates. Specifically, it could be obtained according to the following steps:

[0150] a) First, cellulase was used to carry out an enzymatic hydrolysis reaction on the untreated corncobs. In this comparative example, the preparation method and operation steps of the enzymatic hydrolysis solution were the same as those in Example 1. The enzymatic hydrolysis conditions of the corncobs included: the dosage of cellulase was about 50 FPU per gram of corncobs, 10 g of corncobs were added to 100 mL of the enzymatic hydrolysis solution, the enzymatic hydrolysis temperature was 50 °C, the pH value was 4.8, and the enzymatic hydrolysis time was 72 hours.

[0151] b) Finally, yeast is used to ferment the corncob enzymatic hydrolysate under anaerobic conditions to prepare a fermentation broth rich in ethanol intermediates. In this comparative example, the preparation method and operation steps of the fermentation medium are the same as those in Example 1. The fermentation conditions of the corncob enzymatic hydrolysate include: adding 5 ml of seed medium to 100 mL of fermentation medium, a fermentation temperature of 30 °C, a pH value of 5.5, and a fermentation time of 96 hours.

[0152] In this comparative example, the fermentation products are quantitatively analyzed by gas chromatography-mass spectrometry and high performance liquid chromatography. The effects of using untreated corncobs to prepare fermentation broth rich in ethanol intermediates through sequential enzymatic hydrolysis and fermentation biorefining processes are shown in Table 1 in detail. The ethanol yield obtained is 21.5%, and the ethanol concentration is 25.2 g / L.

[0153] Table 1 Effects of pretreating corncobs with V-MOF / H2O2, enzymatic hydrolysis, and fermentation to prepare fermentation broth rich in ethanol intermediates

[0154]

[0155] As can be seen from Table 1, using V-MOF / H2O2 pretreatment improves the efficiency of converting corncob biomass into fermentation broth rich in ethanol intermediates through enzymatic hydrolysis and fermentation processes. The maximum ethanol yield reaches 35.2%, and the maximum ethanol concentration is 40.9 g / L.

[0156] Example 6

[0157] In this example, the effects of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as the reactant and using a 2% Ce-SAPO34 / 2% Ni-HBET composite catalyst for one-pot catalytic conversion to synthesize bio-aviation kerosene were investigated.

[0158] In this example, the 2% Ce-SAPO34 component in the 2% Ce-SAPO34 / 2% Ni-HBET composite catalyst is obtained by hydrothermal synthesis, and the specific preparation steps are as follows:

[0159] a) Add SAPO34 molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and cerium nitrate (0.46 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0160] b) React the above mixed solution in a stainless steel autoclave at 200 °C for 24 hours;

[0161] c) Wash the precipitate after the reaction, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain a 2% Ce-SAPO34 component powder with a Ce content of about 2.0 wt%.

[0162] d) The pore size of the Ce-SAPO34 component material prepared by the above method is 2.5 nm, the specific surface area is 580 m 2 / g, and the pore volume is 0.18 cm 3 / g.

[0163] In this example, the 2% Ni-HBET component in the 2% Ce-SAPO34 / 2% Ni-HBET composite catalyst is obtained by a hydrothermal synthesis method, and can be specifically prepared according to the following steps:

[0164] a) Add the HBET molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and nickel nitrate (0.63 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0165] b) React the above mixed solution in a stainless steel autoclave at 200 °C for 24 hours;

[0166] c) Wash the precipitate after the reaction, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain a Ni-HBET component powder with a Ni content of 2.0 wt%;

[0167] d) The pore size of the 2% Ni-HBET component material prepared by the above method is 7.5 nm, the specific surface area is 470 m 2 / g, and the pore volume is 0.16 cm 3 / g.

[0168] In this example, the reactants are derived from the fermentation broth rich in ethanol intermediates obtained by pretreating corncobs in Example 4 with a 500 ppm V-MOF / 5% H2O2 solution, enzymatic hydrolysis, and fermentation in sequence.

[0169] In this example, a 2% Ce-SAPO34 / 2% Ni-HBET composite catalyst is used. Through the design of a one-pot reaction mode of catalytic dehydration, olefin polymerization, and hydrogenation saturation, the fermentation broth rich in ethanol intermediates can be catalytically converted into bio-aviation kerosene in one step in the same reactor.

[0170] In this embodiment, the reaction conditions for synthesizing aviation kerosene using a fermentation broth rich in ethanol intermediates are as follows: the mass ratio of 2% Ce-SAPO34 components and 2% Ni-HBET in the 2% Ce-SAPO34 / 2% Ni-HBET composite catalyst is 1:2, the mass ratio of the composite catalyst to the ethanol intermediate-rich fermentation broth is 1:10, the catalytic reaction temperature is 210°C, the catalytic reaction pressure is 5.0 MPa, and the catalytic reaction time is 5 hours.

[0171] In this embodiment, the preparation of aviation kerosene from the fermentation liquid rich in ethanol intermediate adopts a one-pot reaction mode of catalytic dehydration, olefin polymerization, and hydrogenation saturation, that is, in the same reactor, a 2% Ce-SAPO34 component is used to carry out the selective catalytic dehydration reaction of the ethanol-rich intermediate, and a 2% Ni-HBET component is used to carry out the olefin polymerization and hydrogenation saturation reaction. The specific operation steps are as follows: (1) First, fill the front section of the cylindrical fixed-bed reactor with 2% Ni-HBET component in the composite catalyst, and fill the rear section of the cylindrical fixed-bed reactor with 2% Ni-HBET component in the composite catalyst, and separate the two components with quartz sand; (2) purge with nitrogen or other inert gas for 1 hour, and then switch to hydrogen to ensure that the catalyst bed is at the set reaction pressure; (3) Heat the reactor to a set temperature of 210°C. After the temperature is constant, open the injection valve and inject the fermentation liquid rich in ethanol intermediate using a syringe pump; (4) Carry out catalytic synthesis according to the set reaction time. After the reaction is completed, the product is quantitatively analyzed by chromatography-mass spectrometry.

[0172] In this example, the conversion rate of the ethanol-rich intermediate obtained using the 2% Ce-SAPO34 / 2% Ni-HBET composite catalyst was 90.7%, and the yield of aviation kerosene was 60.0%. Detailed results are shown in Table 2.

[0173] Example 7

[0174] In this example, the effect of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as a reactant and using a 3% Ce-SAPO34 / 5% Ni-HBET composite catalyst to carry out one-pot catalytic conversion to synthesize bio-jet fuel was investigated.

[0175] In this embodiment, the 3% Ce-SAPO34 component in the 3% Ce-SAPO34 / 5% Ni-HBET composite catalyst is obtained by hydrothermal synthesis, which can be prepared according to the following steps:

[0176] a) SAPO34 molecular sieve (10 g) and cerium nitrate (0.70 g) provided by Nankai University Catalyst Plant (Tianjin, China) were added to 50 mL of deionized water and stirred for 10 minutes. Ammonia water was then added to the mixed solution to adjust the pH to 9, and the mixture was stirred continuously at room temperature for 5 hours.

[0177] b) React the above mixed solution in a stainless-steel autoclave at 200 °C for 24 hours;

[0178] c) Wash the precipitate after the reaction, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain a 3% Ce-SAPO34 component powder with a Ce content of about 3.0 wt%;

[0179] d) The pore size of the Ce-SAPO34 component material prepared by the above method is 2.3 nm, the specific surface area is 590 m 2 / g, and the pore volume is 0.19 cm 3 / g.

[0180] In this example, the 5% Ni-HBET component in the 3% Ce-SAPO34 / 5% Ni-HBET composite catalyst is obtained by a hydrothermal synthesis method, and the specific preparation steps are as follows:

[0181] a) Add the HBET molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and nickel nitrate (1.57 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0182] b) React the above mixed solution in a stainless-steel autoclave at 200 °C for 24 hours;

[0183] c) Wash the precipitate after the reaction, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain a Ni-HBET component powder with a Ni content of 5.0 wt%;

[0184] d) The pore size of the 5% Ni-HBET component material prepared by the above method is 8.0 nm, the specific surface area is 490 m 2 / g, and the pore volume is 0.17 cm 3 / g.

[0185] In this example, the reactants are derived from the fermentation broth rich in ethanol intermediates obtained by pretreating corncobs in Example 4 with a 500 ppm V-MOF / 5% H2O2 solution, enzymatic hydrolysis, and fermentation in sequence.

[0186] In this example, the reaction conditions for synthesizing aviation kerosene using a fermentation broth rich in ethanol intermediates are as follows: in the 3% Ce-SAPO34 / 5% Ni-HBET composite catalyst, the mass ratio of the 3% Ce-SAPO34 component to 5% Ni-HBET is 1:2, the mass ratio of the composite catalyst to the fermentation broth rich in ethanol intermediates is 1:11, the catalytic reaction temperature is 205 °C, the catalytic reaction pressure is 4.9 MPa, and the catalytic reaction time is 5 hours.

[0187] In this example, the preparation of aviation kerosene from a fermentation broth rich in ethanol intermediates adopts a one-pot reaction mode of catalytic dehydration, olefin polymerization, and hydrogenation saturation, that is, in the same reactor, the selective catalytic dehydration reaction of the ethanol intermediate-rich fermentation broth is carried out using the 3% Ce-SAPO34 component, and the olefin polymerization and hydrogenation saturation reactions are carried out using the 5% Ni-HBET component. The specific operation steps are the same as those described in Example 6.

[0188] In this example, when using the 3% Ce-SAPO34 / 5% Ni-HBET composite catalyst, the conversion rate of the ethanol intermediate-rich fermentation broth obtained is 95.9%, and the yield of aviation kerosene is 68.0%. For the specific results, see Table 2.

[0189] Example 8

[0190] In this example, the effect of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as the reactant and using the 3% Ce-SAPO34 / 7% Ni-HBET composite catalyst for one-pot catalytic conversion to synthesize bio-aviation kerosene was investigated.

[0191] In this example, the 3% Ce-SAPO34 component in the 3% Ce-SAPO34 / 7% Ni-HBET composite catalyst was obtained by the hydrothermal synthesis method, and the specific synthesis steps are the same as those described in Example 7.

[0192] In this example, the 7% Ni-HBET component in the 3% Ce-SAPO34 / 7% Ni-HBET composite catalyst was obtained by the hydrothermal synthesis method, and the specific preparation steps are as follows:

[0193] a) Add HBET molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and nickel nitrate (2.2 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0194] b) React the above mixed solution in a stainless steel autoclave at 200 °C for 24 hours;

[0195] c) Wash the precipitate after the reaction, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain Ni-HBET component powder with a Ni content of 7.0 wt%.

[0196] d) The pore diameter of the 7% Ni-HBET component material prepared by the above method is 6.8 nm, the specific surface area is 450 m 2 / g, and the pore volume is 0.16 cm 3 / g.

[0197] In this example, the reactants are from the fermentation broth rich in ethanol intermediates obtained by pretreating corncobs in Example 4 with 500 ppm V-MOF / 5% H2O2 solution, enzymatic hydrolysis, and fermentation in sequence.

[0198] In this example, the reaction conditions for synthesizing aviation kerosene using the fermentation broth rich in ethanol intermediates are as follows: the mass ratio of the 3% Ce-SAPO34 component to the 7% Ni-HBET in the 3% Ce-SAPO34 / 7% Ni-HBET composite catalyst is 1:2, the mass ratio of the composite catalyst to the fermentation broth rich in ethanol intermediates is 1:10, the catalytic reaction temperature is 210 °C, the catalytic reaction pressure is 4.8 MPa, and the catalytic reaction time is 5 hours.

[0199] In this example, the catalytic dehydration, olefin polymerization, and hydro-saturation one-pot reaction mode are adopted for preparing aviation kerosene from the fermentation broth rich in ethanol intermediates, that is, in the same reactor, the selective catalytic dehydration reaction of the ethanol intermediates is carried out using the 3% Ce-SAPO34 component, and the olefin polymerization and hydro-saturation reactions are carried out using the 7% Ni-HBET component. The specific operation steps are the same as those described in Example 6.

[0200] In this example, when using the 3% Ce-SAPO34 / 7% Ni-HBET composite catalyst, the conversion rate of the ethanol intermediates obtained is 93.4%, and the yield of aviation kerosene is 64.7%. For the specific results, see Table 2.

[0201] Example 9

[0202] In this example, the effect of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as the reactant and using the 5% Ce-SAPO34 / 7% Ni-HBET composite catalyst for one-pot catalytic conversion to synthesize bio-aviation kerosene was investigated.

[0203] In this example, the 5% Ce-SAPO34 component in the 5% Ce-SAPO34 / 7% Ni-HBET composite catalyst was obtained by the hydrothermal synthesis method, and the specific preparation steps are as follows:

[0204] a) Add the SAPO-34 molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and cerium nitrate (1.15 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0205] b) React the above mixed solution in a stainless-steel autoclave at 200 °C for 24 hours;

[0206] c) Wash the precipitate after the reaction, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain 5% Ce-SAPO-34 component powder with a Ce content of about 5.0 wt%;

[0207] d) The pore diameter of the Ce-SAPO-34 component material prepared by the above method is 2.4 nm, the specific surface area is 550 m 2 / g, and the pore volume is 0.17 cm 3 / g.

[0208] In this example, the 7% Ni-HBET component in the 5% Ce-SAPO34 / 7% Ni-HBET composite catalyst is obtained by a hydrothermal synthesis method, and the specific synthesis steps are the same as those described in Example 8.

[0209] In this example, the reactants are from the fermentation broth rich in ethanol intermediates obtained by pretreating corncob with 500 ppm V-MOF / 5% H2O2 solution, enzymatic hydrolysis and fermentation in Example 4.

[0210] In this example, the reaction conditions for synthesizing aviation kerosene using the fermentation broth rich in ethanol intermediates are as follows: the mass ratio of the 5% Ce-SAPO34 component to 7% Ni-HBET in the 5% Ce-SAPO34 / 7% Ni-HBET composite catalyst is 1:1, the mass ratio of the composite catalyst to the fermentation broth rich in ethanol intermediates is 1:10, the catalytic reaction temperature is 210 °C, the catalytic reaction pressure is 5.0 MPa, and the catalytic reaction time is 5 hours.

[0211] In this example, the preparation of aviation kerosene from the fermentation broth rich in ethanol intermediates adopts a one-pot reaction mode of catalytic dehydration, olefin polymerization, and hydrogenation saturation, that is, in the same reactor, the selective catalytic dehydration reaction of the ethanol intermediate-rich fermentation broth is carried out using the 5% Ce-SAPO34 component, and the olefin polymerization and hydrogenation saturation reactions are carried out using the 7% Ni-HBET component. The specific operation steps are the same as those described in Example 6.

[0212] In this example, when using the 5% Ce-SAPO34 / 7% Ni-HBET composite catalyst, the conversion rate of the ethanol-rich intermediate obtained is 91.5%, and the yield of aviation kerosene is 59.3%. For specific results, see Table 2.

[0213] Example 10

[0214] In this example, the effect of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as the reactant and using the 5% Ce-SAPO34 / 10% Ni-HBET composite catalyst for one-pot catalytic conversion to synthesize bio-aviation kerosene was investigated.

[0215] In this example, the 5% Ce-SAPO34 component in the 5% Ce-SAPO34 / 10% Ni-HBET composite catalyst was obtained by the hydrothermal synthesis method, and the specific synthesis steps were the same as those described in Example 9.

[0216] In this example, the 10% Ni-HBET component in the 5% Ce-SAPO34 / 10% Ni-HBET composite catalyst was obtained by the hydrothermal synthesis method, and the specific preparation steps were as follows:

[0217] a) Add the HBET molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and nickel nitrate (3.15 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0218] b) React the above mixed solution in a stainless steel autoclave at 200 °C for 24 hours;

[0219] c) Wash the reaction product precipitate, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain a Ni-HBET component powder with a Ni content of 10.0 wt%;

[0220] d) The pore diameter of the 10% Ni-HBET component material prepared by the above method is 7.2 nm, the specific surface area is 440 m 2 / g, and the pore volume is 0.16 cm 3 / g.

[0221] In this example, the reactant was derived from the fermentation broth rich in ethanol intermediates obtained by pretreating corncobs with a 500 ppm V-MOF / 5% H2O2 solution, enzymatic hydrolysis, and fermentation in Example 4.

[0222] In this embodiment, the reaction conditions for synthesizing aviation kerosene using a fermentation broth rich in ethanol intermediates are as follows: the mass ratio of 5% Ce-SAPO34 components and 10% Ni-HBET in a 5% Ce-SAPO34 / 10% Ni-HBET composite catalyst is 1:3, the mass ratio of the composite catalyst to the ethanol intermediate-rich fermentation broth is 1:10, the catalytic reaction temperature is 209°C, the catalytic reaction pressure is 5.0 MPa, and the catalytic reaction time is 5 hours.

[0223] In this example, aviation kerosene was prepared from the ethanol-rich intermediate fermentation broth using a one-pot reaction model of catalytic dehydration, olefin polymerization, and hydrogenation saturation. Specifically, a 5% Ce-SAPO34 component was used for the selective catalytic dehydration of the ethanol-rich intermediate, and a 10% Ni-HBET component was used for the olefin polymerization and hydrogenation saturation reactions in the same reactor. The specific operating procedures were the same as those described in Example 6.

[0224] In this example, the conversion rate of the ethanol-rich intermediate obtained using the 5% Ce-SAPO34 / 10% Ni-HBET composite catalyst was 90.5%, and the yield of aviation kerosene was 59.2%. Detailed results are shown in Table 2.

[0225] Comparative Example 4

[0226] In this example, the effect of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as a reactant and 3% Ce-SAPO34 catalyst to carry out one-pot catalytic conversion to synthesize bio-jet fuel was investigated.

[0227] In this embodiment, the 3% Ce-SAPO34 catalyst is obtained by hydrothermal synthesis, which can be prepared by the following steps:

[0228] a) SAPO34 molecular sieve (10 g) and cerium nitrate (0.70 g) provided by Nankai University Catalyst Plant (Tianjin, China) were added to 50 mL of deionized water and stirred for 10 minutes. Ammonia water was then added to the mixed solution to adjust the pH to 9, and the mixture was stirred continuously at room temperature for 5 hours.

[0229] b) reacting the mixed solution in a stainless steel autoclave at 200° C. for 24 hours;

[0230] c) washing the precipitate after the reaction, drying it at 100° C. for 12 hours, and sintering the dried precipitate at 600° C. for 5 hours to obtain a 3% Ce-SAPO34 component powder having a Ce content of approximately 3.0 wt%;

[0231] d) The pore size of the Ce-SAPO34 component material prepared by the above method is 2.3 nm and the specific surface area is 590 m 2 / g, the pore volume is 0.19 cm 3 / g.

[0232] In this comparative example, the reactants are from the fermentation broth rich in ethanol intermediates obtained by subjecting corncobs in Example 4 to pretreatment, enzymatic hydrolysis, and fermentation in sequence.

[0233] In this comparative example, the reaction conditions for the directional preparation of aviation kerosene using the fermentation broth rich in ethanol intermediates are as follows: the mass ratio of the 3% Ce-SAPO34 catalyst to the fermentation broth rich in ethanol intermediates is 1:10, the catalytic reaction temperature is 210 °C, the catalytic reaction pressure is 4.9 MPa, and the catalytic reaction time is 5 hours. In this comparative example, the specific operating steps adopted are the same as those described in Example 6.

[0234] In this example, when using the 3% Ce-SAPO34 catalyst, the conversion rate of the ethanol intermediate-rich product obtained is 87.5%, and the yield of aviation kerosene is 13.5%. For specific results, see Table 2.

[0235] Comparative Example 5

[0236] In this example, the effect of using the fermentation broth rich in ethanol intermediates obtained in Example 4 as the reactant and using the 5% NiHBET catalyst for one-pot catalytic conversion to synthesize bio-aviation kerosene was investigated.

[0237] In this example, the 5% NiHBET catalyst was obtained by the hydrothermal synthesis method, and the specific preparation steps are as follows:

[0238] a) Add HBET molecular sieve (10 g) provided by Nankai University Catalyst Factory (Tianjin, China) and nickel nitrate (1.57 g) to 50 mL of deionized aqueous solution, stir for 10 minutes, then add ammonia water to the above mixed solution to adjust the pH value to 9, and continuously stir at room temperature for 5 hours;

[0239] b) React the above mixed solution in a stainless steel autoclave at 200 °C for 24 hours;

[0240] c) Wash the reaction product precipitate, dry it at 100 °C for 12 hours, and sinter the dried precipitate at 600 °C for 5 hours to obtain a Ni-HBET component powder with a Ni content of 5.0 wt%;

[0241] d) The pore diameter of the 5% Ni-HBET component material prepared by the above method is 8.0 nm, the specific surface area is 490 m 2 / g, and the pore volume is 0.17 cm 3 / g.

[0242] In this embodiment, the reactants are derived from the fermentation broth rich in ethanol intermediates obtained by pretreating corncobs in Example 4 with a 500 ppm V-MOF / 5% H2O2 solution, followed by enzymatic hydrolysis and fermentation.

[0243] In this comparative example, the reaction conditions for the directional preparation of aviation kerosene using the fermentation broth rich in ethanol intermediates were as follows: the mass ratio of the 5% Ni-HBET catalyst to the fermentation broth rich in ethanol intermediates was 1:10, the catalytic reaction temperature was 210 °C, the catalytic reaction pressure was 5.0 MPa, and the catalytic reaction time was 5 hours. In this comparative example, the specific operating steps were the same as those described in Example 6.

[0244] In this embodiment, when using the 5% Ni-HBET catalyst, the conversion rate of the ethanol intermediate-rich fermentation broth was 85.0%, and the yield of aviation kerosene was 51.6%. For the specific results, see Table 2.

[0245] Table 2 Results of synthesizing aviation kerosene from the fermentation broth rich in ethanol obtained from corncobs

[0246]

[0247]

[0248] As can be seen from Table 2, using the fermentation broth rich in ethanol intermediates obtained by enzymatic hydrolysis and fermentation of corncobs as the raw material, under the action of the Ce-SAPO34 / Ni-HBET composite catalyst, the fermentation broth rich in ethanol intermediates can be directionally converted into bio-aviation kerosene. Through the design of the Ce-SAPO34 / Ni-HBET composite catalyst and the one-pot reaction mode, the present invention improves the selectivity of bio-aviation kerosene and effectively realizes the goal of selectively synthesizing bio-aviation fuel from corncob biomass. Experiments show that the conversion rate of the fermentation broth rich in ethanol intermediates described in the present invention reaches a maximum of 95.9%, and the selectivity of aviation kerosene reaches a maximum of 68.0%.

[0249] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A preparation method of aviation kerosene, characterized in that, It includes the following steps: a) Pretreat the corncob biomass successively with V-MOF / H2O2, carry out enzymatic hydrolysis and fermentation to obtain a fermentation broth rich in ethanol intermediates; b) Carry out one-pot catalytic conversion on the fermentation broth rich in ethanol intermediates obtained in step a) under the action of a Ce-SAPO34 / Ni-HBET composite catalyst to obtain aviation kerosene.

2. The preparation method according to claim 1, characterized in that, The corncob biomass described in step a) includes: Cellulose 40wt% - 45wt%; Hemicellulose 35wt% - 40wt%; Lignin 12wt% - 15wt%; The rest is other components.

3. The preparation method according to claim 1, characterized in that, In the V-MOF / H2O2 pretreatment solution used for the V-MOF / H2O2 pretreatment in step a), it contains 100ppm - 1000ppm of V-MOF component and 1% - 10% of H2O2 component.

4. The preparation method according to claim 1, wherein The specific description of step a) is as follows: Pretreat the corncob biomass at 20°C - 30°C and pH = 6 - 7 with the V-MOF / H2O2 pretreatment solution to obtain the pretreated corncob; then carry out enzymatic hydrolysis reaction on the pretreated corncob with cellulase to obtain the corncob enzymatic hydrolysate; finally, carry out microbial fermentation on the corncob enzymatic hydrolysate with yeast to obtain a fermentation broth rich in ethanol intermediates.

5. The preparation method according to claim 4, wherein, The temperature of the enzymatic hydrolysis reaction is 40°C - 60°C, and the pH value is 4.5 - 5.

6. The preparation method according to claim 4, characterized in that, The temperature of the microbial fermentation is 20°C - 40°C, and the pH value is 5 - 6.

7. The preparation method according to claim 1, characterized in that, In the Ce-SAPO34 / Ni-HBET composite catalyst described in step b), it contains 1% - 5% of Ce-SAPO34 component and 2% - 10% of Ni-HBET component; the mass ratio of the 1% - 5% Ce-SAPO34 component to the 2% - 10% Ni-HBET component is 1:(1.5 - 3).

8. The preparation method according to claim 1, characterized in that, The mass ratio of the fermentation broth rich in ethanol intermediates to the Ce-SAPO34 / Ni-HBET composite catalyst in step b) is (5 - 15):

1.

9. The preparation method according to claim 1, wherein, The reaction temperature of the one-pot catalytic conversion in step b) is 200°C - 220°C, the reaction pressure is 4MPa - 6MPa, and the reaction time is 4h - 6h.

10. The preparation method according to claim 1, characterized in that, The conversion rate of the fermentation broth rich in ethanol intermediates reaches up to 95.9%, and the yield of the aviation kerosene reaches up to 68.0%.

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