327 results about "Furaldehyde" patented technology

The invention discloses a cobalt-copper bimetallic nitrogen-doped carbon catalyst, which is characterized in that CoCu-coated LNC, Co and Cu nanoparticles are anchored on a nitrogen-doped carbon carrier derived from lignin. Accordingly, the inventor also establishes a corresponding preparation method, and the catalyst is prepared by taking lignin as a carrier, cobalt-copper bimetal as an active component and dicyandiamide as a nitrogen source through one-pot pyrolysis. The method has the characteristics of simple and efficient process, high catalyst stability and activity, economy, high efficiency, environmental friendliness and the like. The method is used for preparing 2, 5-furandicarboxylic acid through thermal catalytic oxidation of 5-hydroxymethylfurfural, the yield of the target product FDCA almost reaches 100%, and the application prospect is wide.

The invention discloses a lignin-based epoxy anticorrosive paint and a preparation method thereof. The anticorrosive paint is prepared by mixing a lignin-based epoxy anticorrosive paint component, a lignin-based phenolic amine curing agent and a diluent. According to the lignin-based epoxy anticorrosive paint disclosed by the invention, on one hand, a lignin epoxy resin acetylation modification method based on lipase is introduced, and the content of hydrophilic groups is reduced, so that formation of a compact lignin cross-linked network structure is promoted, and the barrier ability, heat resistance and aging resistance of an anticorrosive coating on a chemical medium are improved on the resin level; on the other hand, lignin and furfural are respectively used for partially replacing phenol and paraformaldehyde to prepare a lignin-based phenolic aldehyde amine curing agent with high chemical inertness, so that the protection effect of a coating in an extreme corrosion environment and the adhesive force to a metal base material are improved on the curing agent level. The lignin-based epoxy anticorrosive paint prepared by the invention has good corrosion resistance, aging resistance, thixotropy and adhesive force.

The invention belongs to the technical field of chemical synthesis, and particularly relates to a method for preparing 5-methylfurfural by using 2-methylfuran. The special solid acid catalyst is used for replacing traditional phosphorus oxychloride, hydrogen chloride and phosphorus-containing wastewater are eliminated from the source, and the sulfolane is used for replacing DMF (Dimethyl Formamide), so that solvent residues in the product are reduced. The solid catalyst SO4 < 2-> is modified to form a strong Bronsted acid site (-SO3H) which cooperates with Ce < 3 + > / Ce < 4 + > redox to inhibit carbon deposition, selectively activate 2-methylfuran alpha-C and inhibit side reactions, so that the selectivity and yield of a target product are improved. Na2CO3 neutralization is replaced by electrochemical neutralization, salt slag solid waste is eliminated, and environmental pollution is reduced. After the organic phase is dried and dewatered through a molecular sieve, most of the solvent is removed through rotary evaporation, and the residual crude product is subjected to centrifugal molecular distillation, so that unreacted raw materials and trace impurities are effectively removed, and the product purity is remarkably improved.

The invention discloses 5-hydroxymethylfurfural and a preparation method thereof, and belongs to the technical field of chemical engineering. The preparation method comprises the following steps: reacting a homogeneous aqueous solution containing fructose, inorganic salt and an acid catalyst in a multi-kettle series reactor to obtain the 5-hydroxymethylfurfural, the inorganic salt is selected from at least one of halogen compounds, borides, silicate, aluminate, phosphate and borate; the acidic catalyst comprises at least one of water-soluble acids. The specific inorganic salt and the specific acid catalyst are added and can play a synergistic role, the reaction is carried out under multi-kettle series connection, the backmixing degree of the reaction materials in the reactor is maximized, side reactions can be effectively controlled, black rot is avoided, the reaction production efficiency and conversion rate are effectively improved, the reaction selectivity is improved, and the method is suitable for industrial production. And the equipment maintenance and labor cost is greatly reduced.

The invention discloses a preparation method of a sulfonic acid type covalent organic framework material and a preparation method of 5-hydroxymethylfurfural. The material is prepared by carrying out covalent condensation reaction on a monomer containing a sulfonic acid group precursor and a connecting ligand of a skeleton through a hot solvent method, and the catalyst has the characteristics of high crystallinity, large specific surface area, ordered pore structure, high sulfonic acid group density and uniform distribution. The preparation method is simple, convenient, efficient, mild in condition and high in yield. Compared with a traditional lewis acid catalyst for preparing 5-hydroxymethylfurfural through fructose dehydration, the material has the advantages of being uniform and adjustable in porosity, higher in active site, capable of promoting fructose hydrolysis and the like, efficient conversion can be achieved, side reactions and product transition polymerization are inhibited, and better industrialization prospects are shown.

The invention belongs to the technical field of preparation of bio-based platform compounds, and discloses a method for preparing 5-hydroxymethylfurfural by photocatalysis of glucose with a composite membrane, which comprises the following steps: by taking the composite membrane as a catalyst, mixing a glucose aqueous solution and a solvent under illumination conditions, and carrying out catalytic reaction to obtain crude 5-hydroxymethylfurfural production liquid; the method is used for solving the problems of low conversion rate, more byproducts, difficulty in continuous preparation, poor water resistance, strong corrosion and the like of the synthesis of 5-hydroxymethylfurfural. According to the method, a glucose solution passes through a composite membrane assembled by a mesoporous high-entropy sulfide membrane and a microporous zeolite molecular sieve membrane in a continuous flow manner, is efficiently isomerized into fructose under the action of illumination, and is dehydrated and continuously converted into 5-hydroxymethylfurfural. The composite membrane used in the method is high in water resistance, clean and non-toxic, has double functions of reaction and separation, effectively prevents the 5-hydroxymethylfurfural from further reacting with substances such as water and the like to generate humus, and realizes high-selectivity and continuous preparation of the 5-hydroxymethylfurfural.

The invention discloses a carbon-doped carbon nitride nanotube as well as a preparation method and application thereof in photocatalytic reaction, and belongs to the technical field of inorganic photocatalytic nano materials. Comprising the following steps: roasting urea, melamine and 2, 4, 6-triaminopyridine under protective gas; adding the carbon-doped carbon nitride nanotube, 5-hydroxymethylfurfural and chloroplatinic acid hexahydrate into the deionized water; photocatalytic hydrogen evolution is started to cooperate with selective oxidation reaction of 5-hydroxymethylfurfural. The carbon-doped carbon nitride prepared by the preparation method disclosed by the invention is in a nanotube shape; and the catalyst can be effectively applied to solar photocatalytic hydrogen evolution to cooperate with selective oxidation of 5-hydroxymethylfurfural to generate 2, 5-diformyl furan. The invention mainly solves the problems that the value-added reaction cooperated with the hydrogen production process cannot be realized and the overall economic value cannot be improved in the traditional hydrogen production means. The method is an effective, practical and simple method, is suitable for laboratory preparation and industrial production, and has huge development space and application prospect.

The invention discloses a metal organic coordination porous polymer derivative catalyst for preparing 2, 5-dimethylfuran through hydrogenation of 5-hydroxymethylfurfural, and the catalyst is prepared by calcining and deriving after anchoring a metal active component by a metal organic coordination porous polymer, the metal organic coordination porous polymer is formed by coordination of one or two metals selected from cerium and zirconium and an organic carboxylic acid ligand; the metal active component is at least one of copper, nickel and cobalt. The invention discloses an application of a catalyst in preparation of 2, 5-dimethylfuran by hydrogenation of 5-hydroxymethylfurfural. According to the invention, the anchoring capability of uncoordinated carboxylic acid of an organic carboxylic acid ligand in the metal organic coordination porous polymer is utilized to stabilize the metal active component, the agglomeration phenomenon in the calcining and reaction process is obviously inhibited, and meanwhile, the mass transfer path of reactants is optimized through ordered pore channels of the metal organic coordination porous polymer. The catalyst provided by the invention improves the conversion rate of 5-hydroxymethylfurfural and the selectivity of 2, 5-dimethylfuran.

The invention relates to the technical field of chemical synthesis, and discloses a method for preparing 2, 5-furandicarboxylic acid, which comprises the following steps: dispersing cobalt nitrate and nickel sulfate into an aqueous solution of polyvinylpyrrolidone at room temperature; adding a sodium borohydride solution to obtain nano colloid; preparing an aqueous suspension of cerium oxide, and adding the aqueous suspension into the nano colloid; centrifugally filtering, and recovering a solid product; washing the solid product; centrifuging, putting solid powder obtained after centrifuging into a drying oven, and drying; and calcining and grinding the solid powder to finally prepare the Co-Ni / CeO2 catalyst. And dissolving 5-hydroxymethylfurfural in water at normal temperature, adding the prepared Co-Ni / CeO2 catalyst and a sodium hypochlorite solution, reacting, and filtering to remove the catalyst, thereby obtaining the 2, 5-furandicarboxylic acid. The method disclosed by the invention has the advantages of no use of strong base, low reaction temperature, short reaction time, few byproducts, greenness and sustainability.

The invention provides a preparation method of a hydrotalcite-derived cobalt-copper catalyst and application of the hydrotalcite-derived cobalt-copper catalyst in furfural hydrogenation reaction. A series of different layered composite metal oxide precursors are prepared through coprecipitation and ion exchange methods, the layered composite metal oxide precursors are applied to furfural hydrogenation reaction after being pre-reduced, and the reaction with pentanediol and furfuryl alcohol as target products shows excellent catalytic activity. By designing the element composition and structural distribution of the hydrotalcite precursor, the composition, the structure and the physical property of the catalyst are effectively modulated, and the distribution of hydrogenation products is effectively regulated and controlled. The furfural can be completely converted on the Co < 1.5 > Cu < 0.25 > Al < 0.5 > Ox catalyst, and the yield of the product pentanediol reaches 68.8%; the yield of the product furfuryl alcohol reaches 98% on the basis of the Co < 1.5 > Cu < 0.25 > Al < 1.75 > catalyst. Characterization results of the catalyst show that the hydrogenation performance of the catalyst strongly depends on sample element composition, valence states of active species Cu and Co, structural distribution and dispersity of the active species Cu and Co in a precursor and a synergistic effect among different species.

The invention provides a continuous flow preparation method of a CuPd / C catalyst. The method is simple and efficient, and one-step and continuous production can be realized. The method has the core advantages that multi-phase flow is ordered, the mixing efficiency is high, reaction parameters are accurate and adjustable, the repeatability and the automation degree are remarkably superior to those of a traditional impregnation method, and the problems that the traditional method is long in time consumption, low in selectivity, high in operation dependency, uneven in mixing and the like are effectively solved. In addition, catalyst synthesis conditions are screened, and optimal preparation conditions are determined. According to the CuPd / C catalyst prepared by the method, the conversion rate of 2, 5-dimethylfuran prepared from 5-hydroxymethylfurfural can reach 100%, and the selectivity of 2, 5-dimethylfuran can reach 97.5%. Compared with a CuPd / C catalyst prepared by an impregnation method, the yield of 2, 5-dimethylfuran is improved by more than 34.5%, and is superior to most reported catalysts at present. And mechanical operation can avoid personal errors, so that the result is easier to repeat, and the production efficiency is improved.

The application relates to a preparation method of PdAg nanosponge and application of the PdAg nanosponge. A certain amount of ethylene glycol is configured into an ethylene glycol aqueous solution, a certain volume of the ethylene glycol aqueous solution is added into a reaction container, then a certain amount of a Pd precursor is quickly added into the ethylene glycol aqueous solution, a certain amount of an Ag precursor is further added, the reaction system is uniformly mixed through ultrasonic, and then the reaction system is statically reacted at 20-60 DEG C for 0.5-3.0 h. After the reaction is completed, the reaction product is centrifuged, the obtained precipitate after centrifugation is washed through ultrapure water, and the PdAg nanosponge is obtained after drying. The application does not need to use a surfactant and a template agent, does not need to additionally add a reducing agent, does not need high temperature, high pressure, stirring and other reaction conditions, and can be statically reacted at 20-60 DEG C, so that the reaction condition is mild and the reaction step is simple. The prepared PdAg nanosponge has a 3D sponge-like structure and is a self-supporting catalyst, the purity is high, and the PdAg nanosponge has excellent catalytic activity and selectivity for selective hydrogenation reaction of furfural.

The invention provides a preparation method for synthesizing 5-hydroxymethylfurfural by catalyzing glucose through a phosphotungstic acid modified molecular sieve catalyst. Organic amine is adopted as a template to synthesize a silicoaluminophosphate (SAPO) molecular sieve, the SAPO molecular sieve subjected to high-temperature activation is adopted as a catalyst, the SAPO molecular sieve and phosphotungstic acid are subjected to composite roasting, a phase transfer catalyst is added into a two-phase medium of an organic solvent and water, glucose is dehydrated and converted into 5-hydroxymethylfurfural (5-HMF), the yield of the 5-HMF is 50% or above, and the selectivity of the 5-HMF exceeds 90%. After the catalyst is recycled for multiple times, the yield of 5-HMF exceeds 40%.

The application discloses a furaldehyde aqueous phase rearrangement hydrogenation catalyst, a preparation method thereof and a method for preparing cyclopentanol by catalyzing furaldehyde aqueous phase rearrangement hydrogenation, the catalyst is a silica supported metal, the metal is at least one of copper, nickel, cobalt and zinc, the metal accounts for 0.25-11% of the total weight of the catalyst, the catalyst, furaldehyde and water are added into a batch type closed high-pressure reaction kettle, and cyclopentanol is prepared by catalytic selective hydrogenation under stirring, a zinc-doped copper phyllosilicate catalyst is prepared, the catalyst does not destroy the original copper phyllosilicate phase after modification, and the catalyst acidity, especially the Lewis acid site, is obviously improved; and the modified copper phyllosilicate catalyst is uniform in particles, high in specific surface area and acidity, low in price, renewable, and has a wide industrial application prospect.

The application discloses a bimetallic doped hierarchical porous carbon catalyst and a preparation method and application thereof. The bimetallic doped hierarchical porous carbon catalyst is prepared from two transition metal salts and specific biomass powder as raw materials through 160-180 DEG C hydrothermal carbonization and 200-500 DEG C calcination. The catalyst has simple components, is cheap, and has a simple preparation process. The catalyst can efficiently catalyze synthesis of 2,5-furan dicarboxylic acid from 5-hydroxymethylfurfural under mild conditions. The target product has high yield and simple separation, and has a good industrial application prospect.

The invention discloses a method for preparing 2, 5-diformyl furan by selectively oxidizing 5-hydroxymethylfurfural, which comprises the following steps of: reacting 5-hydroxymethylfurfural serving as a raw material, air or oxygen serving as an oxidant, nitrate or ferric salt and sodium iodide serving as main active components of a catalyst and DMSO (dimethylsulfoxide) serving as a solvent at the temperature of between 80 and 160 DEG C for a certain time under the condition of normal pressure, and separating a product to obtain the 2, 5-diformyl furan. The ferric salt is ferric nitrate nonahydrate, and the catalyst is 2, 5-diformyl furan. The dosage of the ferric salt is 0 to 0.50 mmol; the use amount of the sodium iodide is 0 to 0.50 mmol. According to the method, DMSO is adopted as a solvent, the used catalyst is cheap and easy to obtain, the yield of 2, 5-diformyl furan can reach 95% at most after the reaction is carried out at 140 DEG C for 20 h, the requirement for equipment is low, and the method is suitable for industrial production.

The application belongs to the technical fields of functional material preparation, catalysis and transition metal complex material, and discloses a selenium compound heterojunction catalyst coupled with hydrogen evolution, a method and application. In preparation, a cobalt source, urea, a foamed nickel and an ammonium fluoride mixed solution are mixed in a reaction, and after being hydrothermally synthesized and cooled to room temperature, the precursor Co(OH)2 / NF is obtained by washing with ethanol and water and drying. Then, selenium powder and a strong base are added into a reaction kettle, and heating is performed to obtain the heterojunction catalyst NiSe@CoSe2 / NF with high density. The obtained heterojunction material can be used for electrocatalysis of 5-hydroxymethylfurfural. When the current density is 10 mAcm ‑2 , the potential is 1.29 V, and the optimal conversion rate is more than 98%, and the catalyst has excellent catalytic activity for electrocatalysis of 5-hydroxymethylfurfural oxidation.

The invention relates to a process for the production of a mixture of 5-hydroxymethylfurfural and glucose from a feedstock containing fructose in the presence of at least one polar aprotic solvent and of at least one dehydration catalyst, in which process the reaction temperature is less than 90° C.

The invention relates to a spleen-tonifying, appetite-stimulating and digestion-promoting traditional Chinese medicine preparation UPLC detection method and a fingerprint spectrum, and belongs to the technical field of medicine detection. The invention aims to solve the technical problems that the existing quality control method of the spleen-tonifying, appetite-promoting and digestion-promoting pills lacks comprehensive and objective analysis on the spleen-tonifying, appetite-promoting and digestion-promoting pills, and the problems of low precision, poor reproducibility, low efficiency and the like during detection of related components in the prior art are solved. According to the technical scheme, the UPLC detection method is characterized in that a mixed standard substance of gallic acid, 5-hydroxymethylfurfural, chlorogenic acid, sinapine thiocyanate, sinapic acid, hyperoside, 3, 6-dimustard acyl sucrose, hesperidin, naringenin, nobiletin and hesperetin is taken as a contrast, an acetonitrile-0. 1% formic acid aqueous solution is taken as a mobile phase, gradient elution is carried out, and the content of chlorogenic acid in the sample is detected. The qualitative and quantitative detection of the effective components of the spleen-tonifying, appetite-promoting and digestion-promoting pill is realized.

The present invention relates to a metal nitrate hydrate catalyst and a method for preparing 5-hydroxymethylfurfural, using same and, more specifically, may provide: a catalyst which comprises a metal nitrate hydrate and is to prepare 5-hydroxymethylfurfural (HMF) from at least one selected from the group consisting of monosaccharides and disaccharides; and a method for preparing 5-hydroxymethylfurfural (HMF), the method comprising (a) a step of preparing 5-HMF by reaction in the presence of the catalyst from a sugar comprising at least one selected from the group consisting of monosaccharides and disaccharides. The present invention provides high 5-HMF yield and selectivity, biological and process stability, and economic efficiency by using inexpensive monosaccharides and / or disaccharides.

The application discloses an evaluation method for distinguishing different quality of momordica grosvenori of different origins. The application adopts high performance liquid chromatography to establish the fingerprint of momordica grosvenori, carries out gradient elution by taking water-acetonitrile as a mobile phase, and detects the wavelength of 203 nm to obtain the HPLC fingerprint of momordica grosvenori; the obtained chromatogram is introduced into a traditional Chinese medicine chromatographic fingerprint similarity evaluation system to generate a control fingerprint, different origins of momordica grosvenori are distinguished through similarity comparison and / or chemical pattern recognition analysis; and chemical markers with VIP>1 such as 5-hydroxymethyl furfural, momordica grosvenori flavonoid, momordica grosvenori saponin V and momordica grosvenori saponin IIIA2 are screened. The application can effectively distinguish two main origins of green skin fruit and red hair fruit, overcomes the defects that traditional trait identification is subjective and it is difficult to distinguish similar appearance samples, and provides an objective, accurate and stable technical means for origin identification, quality consistency evaluation and authenticity identification of momordica grosvenori.

Provided is a method for producing furan-2,5-dicarboxylic acid, the method comprising: an oxidation step 1 for performing an oxidation reaction by continuously supplying 5-methylfurfural and an oxygen-containing gas under a supply condition 1 or 2 in the presence of a lower aliphatic carboxylic acid, a bromine compound, and a metal catalyst; and an oxidation step 2 for performing an oxidation reaction under a supply condition in which the oxygen concentration of the oxygen-containing gas and / or the molar ratio of oxygen in the oxygen-containing gas to the 5-methylfurfural is greater than those in the oxidation step 1. In the supply condition 1, the oxygen concentration of the oxygen-containing gas is 10 vol% or more and less than 15 vol%, and the molar ratio of oxygen in the oxygen-containing gas to the 5-methylfurfural is 2.5-4.2. In the supply condition 2, the oxygen concentration is 15-30 vol% and the molar ratio is 1.0 or more and less than 2.5.

The invention discloses a colorectal cancer diagnostic marker group based on expiration volatile organic compounds and application of the colorectal cancer diagnostic marker group. The colorectal cancer diagnostic marker group consists of six expiration volatile organic compounds, namely furfural, 2-methyl butane, valeric acid, methyl allyl sulfide, hexane and octanal. According to the method, expiration samples of 182 subjects are analyzed through TD-GC-MS / MS, machine learning is combined, the six expiration volatile organic compounds are screened out, the diagnosis AUC of the combination in a verification queue reaches 0.907, the accuracy rate is 0.806, and the combination is superior to a serum marker combination (AUC = 0.861). The invention further provides the BRS and a colorectal cancer noninvasive diagnosis and risk stratification system, and the BRS and the colorectal cancer noninvasive diagnosis and risk stratification system are used for achieving efficient prediction and risk stratification of the colorectal cancer. Compared with a traditional risk scoring model depending on clinical variables such as age, family history and lifestyle, the BRS provides unique metabonomics information, and the prediction accuracy is remarkably improved.

The invention provides a halogen-free fireproof aluminum-plastic composite panel and a preparation method thereof, and belongs to the technical field of building materials, and the halogen-free fireproof aluminum-plastic composite panel comprises aluminum plate layers and a flame-retardant core layer located in the middle of the aluminum plate layers. The flame-retardant core layer comprises modified polyester resin and an auxiliary additive, the modified polyester resin comprises the following components in parts by weight: 40-60 parts of terephthalic acid, 20-40 parts of ethylene glycol, 5-10 parts of a flame-retardant monomer and 1-3 parts of a catalyst, and the flame-retardant monomer is prepared by reacting 5-hydroxymethylfurfural with 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide. The flame-retardant monomer participates in polycondensation of polyester like terephthalic acid or ethylene glycol, and the flame-retardant effect and the mechanical property of the polyester resin can be improved at the same time.

A synthesis method of 2,5-dihydroxymethyl tetrahydrofuran, comprising: 5-hydroxymethyl furfural is contacted with hydrogen after a plasma generator in the presence of a non-noble metal catalyst to generate 2,5-dihydroxymethyl tetrahydrofuran. The present application uses 5-hydroxymethyl furfural (5-HMF) as raw material, and synthesizes DHMTHF by hydrogen plasma coupling non-noble metal catalyst. The method of the present application does not need to use noble metal, utilizes the high reactivity of excited state particles in hydrogen plasma, reduces the reaction pressure and reaction temperature, and the plasma has the effect of dispersing the catalyst active metal again. The whole reaction process has the characteristics of relatively mild reaction conditions, low hydrogen consumption, high selectivity of target product, simple process, good stability of catalyst, low cost of catalyst, etc.

The invention belongs to the technical field of photocatalysis, and particularly relates to a composite catalyst as well as a preparation method and application thereof. The preparation method of the composite catalyst comprises the following steps: by taking melem as a photocatalytic active center, mixing melem with an H < + > solution at room temperature, and providing additional active sites by utilizing interaction between H < + > in a Bronsted acid solution and melem molecules, so as to prepare the composite catalyst with a synergistic catalytic effect. The acid group is introduced to the surface of the photocatalyst for modification, so that the modified photocatalyst has the properties of a solid acid catalyst at the same time, glucose is induced to be isomerized into fructose under the photocatalysis action of the composite catalyst, and meanwhile, under the synergistic effect of acid catalysis and photocatalysis in the composite catalyst, the fructose content is increased. Fructose is converted into hydroxymethylfurfural with high selectivity, and efficient and targeted preparation of hydroxymethylfurfural under a pollution-free condition is realized.

The invention provides a method for preparing 2, 5-diformyl furan by catalyzing fructose by using an ionic liquid and a vanadium complex, which comprises the following steps: carrying out dehydration reaction by using the fructose as a raw material and the ionic liquid as a reaction solvent and a catalyst to obtain 5-hydroxymethylfurfural, then adding a V / HCP-AQ catalyst, and carrying out oxidation reaction on the 5-hydroxymethylfurfural in an oxygen atmosphere to obtain the 2, 5-diformyl furan. And 3, 5-diformyl furan is obtained. According to the method, the ionic liquid is adopted to replace DMSO to serve as a fructose dehydration and oxidation solvent, ethyl acetate is added into a reaction system for extraction after the reaction is finished, the product 2, 5-diformyl furan can be obtained, and the problem that the product is difficult to separate in the process of preparing the 2, 5-diformyl furan through the fructose one-pot method under a traditional catalytic system is solved.

The present invention provides a method for simultaneously determining 5-hydroxymethylfurfural and its oxidation product, including: providing a reaction mixture obtained after 5-hydroxymethylfurfural is oxidized, the reaction mixture comprising 5-hydroxymethylfurfural and its oxidation product; filtering the reaction mixture to obtain a filtrate and a filter residue; preparing the filtrate as a first solution to be tested, mixing the filter residue with an inorganic base so that the insoluble oxidation product in the filter residue undergoes a salt-forming reaction and dissolves, and preparing the filtrate as a second solution to be tested; performing high performance liquid chromatography analysis on the first solution to be tested and the second solution to be tested, respectively, the conditions for high performance liquid chromatography analysis comprising: an organic acid analytical column as the stationary phase, and a column temperature of 25°C to 60°C; an inorganic acid aqueous solution as the mobile phase, and a flow rate of the mobile phase of 0.4 to 1 mL / min; an injection volume of 1 μL to 20 μL; and adopting dual wavelength detection, with a first detection wavelength of 200 nm to 240 nm and a second detection wavelength of 250 nm to 300 nm. The method provided by the present invention has good separation, high accuracy, and high precision.

The current invention describes a high-throughput catalytic process for the production of diesel fuel from domestic agricultural products, furfuraldehyde and plant fatty acids. In the present process, reacting medium and long chain fatty anhydrides (such as capric, caprylic, lauric and palmitic) with furfuraldehyde by a Perkin condensation produces 2-n-alkenylfurans. In a second step, the 2-n-alkenylfurans are hydrogenated to form 2-n-alkyltetrahydrofurans. Basic fuel property testing (melting point, density, kinematic viscosity, derived cetane number and calorific value) of the 2-n-alkyltetrahydrofurans indicates they are potentially useful as fuels for diesel engines. One mixture composed of 2-octyl- and 2-decyltetrahydrofuran had the best combination of fuel properties including a low melting point (−39° C.), high cetane number (63.1), high flash point (98.2° C.) and low viscosity (2.26 mm2 / sec, 40° C.) which compares favorably with specifications for diesel #2 and biodiesel.

Process for the production of 5-hydroxymethyl-2-furancarboxylic acid (HMFA), wherein 5-hydroxymethylfurfural (HMF), which is present in an aqueous solution, is oxidized to obtain 5-hydroxymethyl-2-furancarboxylic acid (HMFA) by treatment with an NAD(P)+-dependent aldehyde dehydrogenase in vitro with NAD(P)H being formed; after said oxidation step the NAD(P)H formed during the oxidation is enzymatically regenerated with an oxidoreductase back to NAD(P)+, and a keto compound is used as a cosubstrate of the oxidoreductase.