902 results about "Dimethyl carbonate" patented technology

The invention provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a positive pole piece, an isolating membrane, a negative pole piece and electrolyte, and the positive pole piece, the isolating membrane and the negative pole piece are arranged in a laminated manner; the positive pole piece comprises a positive current collector and a positive active layer arranged on at least one side of the positive current collector, the negative pole piece comprises a negative current collector and a negative active layer arranged on at least one side of the negative current collector, and the positive active layer comprises lithium iron phosphate primary particles; the isolating membrane comprises a base membrane and a bonding layer, the bonding layer is of a porous continuous structure, and the bonding layer is at least arranged on one side, facing the positive electrode active layer, of the base membrane; the electrolyte comprises a first solvent, and the first solvent comprises one or more of dimethyl carbonate and linear carboxylic ester. The battery monomer has relatively good cycle performance.

The invention discloses an electrolyte adaptive to a lithium iron manganese phosphate positive electrode material and a battery, and belongs to the technical field of batteries. The electrolyte comprises a non-aqueous solvent, a lithium salt and a negative electrode film-forming additive, the mass ratio a of the total mass of the dimethyl carbonate and the carboxylic ester in the non-aqueous solvent, the molar ratio b of the lithium bis (fluorosulfonyl) imide in the lithium salt, the molar ratio y of manganese in the lithium manganese iron phosphate and the compaction density c of the positive pole piece meet the relational expression: # imgabs0 # 0.01 < = a < = 1; 0.01 < = b < = 1; 1.8 < = c < = 2.7 in g / cm < 3 >; the molecular formula of the lithium manganese iron phosphate is LixMnyFe1-yPO4, x is more than or equal to 0.95 and less than or equal to 1.05, and y is more than or equal to 0.3 and less than or equal to 0.8; and the mass ratio d and y of the negative electrode film-forming additive in the electrolyte meet the relational expression that (100 * d) / y is greater than or equal to 3 and less than or equal to 20, and d is greater than or equal to 0.001 and less than or equal to 0.2. The electrolyte can improve the deposition phenomenon of manganese ions on a negative electrode and improve the conductivity and the dynamic performance.

The invention provides a preparation method of mannitol carbonic acid sulfate, mannitol and dimethyl carbonate are used as starting raw materials to prepare mannitol carbonic acid sulfate, a target compound is obtained through ester exchange, cyclization and oxidation reaction, the raw materials are low in price and easy to obtain, the reaction operation is simple and convenient, the yield of the obtained product is 81% or above, the purity is 99.6% or above, and the method is suitable for industrial production. The method is suitable for industrial production.

The invention is suitable for the technical field of chemical industry, and provides a method for preparing polycarbonate diol by using a titanate catalyst, which comprises the following steps: step 1, transesterification: mixing dimethyl carbonate and 1, 6-hexanediol according to a molar ratio of 1.1-1.5: 1, adding isopropyl titanate which accounts for 0.01-2% of the total raw material amount as a catalyst, and reacting at the temperature of 50-60 DEG C for 1-3 hours; carrying out transesterification on the mixture; step 2, carrying out condensation polymerization to obtain a polycarbonate diol crude product; and step 3, carrying out reduced pressure purification, and removing the small molecular polymer and the residual titanium isopropoxide catalyst to obtain the high-purity polycarbonate diol. According to the present invention, the efficient titanium isopropoxide catalyst is used under the normal pressure, such that the preparation of the high-purity and narrow-molecular-weight-distribution polycarbonate diol is achieved, the operation condition is mild, the production efficiency is high, the cost is low, and the catalyst has characteristics of low boiling point, easy removal and environmental protection.

The invention discloses a method for preparing dimethyl carbonate through reaction of CO and methyl nitrite, belongs to the technical field of preparation of dimethyl carbonate, and aims to solve the problem that in the prior art, in the process of preparing dimethyl carbonate through catalysis of reaction of CO and methyl nitrite, the reaction time is short. The preparation method specifically comprises the following steps: in an inert gas atmosphere, mixing and stirring isocyanatopropyltriethoxysilane and N, N-dimethylformamide, raising the temperature of a reaction system to 50-60 DEG C, carrying out a reaction for 1-2 hours, and carrying out a reaction for 1-2 hours, so as to obtain a reaction solution; and 3-aminopropionic acid is added into the reaction system. According to the method, silicon-aluminum coating, potassium modification and 18-crown-6-ether modification are sequentially performed after a halogen-free palladium-copper catalytic system is prepared, so that the conversion rate of impurities and the chromatic value of a product are reduced, the conversion rate of methyl nitrite is effectively increased, and the service life of the catalyst is effectively prolonged.

The invention provides a single battery, a battery device and a power utilization device, the single battery comprises an electrode assembly, the total width of a positive pole lug part accounts for 50%-100% of the total size of a pole lug connecting edge along the extension direction of the pole lug connecting edge of a positive pole main body part, and the total width of a negative pole lug part accounts for 50%-100% of the total size of the pole lug connecting edge along the extension direction of the pole lug connecting edge of a negative pole main body part; wherein the coating weight of the single negative electrode active material layer is 0.1 g / 1540.25 mm < 2 >-0.145 g / 1540.25 mm < 2 >, the electrolyte comprises at least one of dimethyl carbonate and linear carboxylic ester, the structural formula of the linear carboxylic ester meets R1-COO-R2, and R1 and R2 are independently selected from C1-C5 alkyl or halogenated alkyl respectively; based on the total mass of the organic solvent, the mass fraction of the first solvent is 4-72%.

The invention provides a method and a device for separating azeotrope of ethanol and dimethyl carbonate, and the method comprises the following steps: adding raw materials into an extractive distillation tower for extractive distillation, and then carrying out first heat exchange and condensation on a compressed top gas phase of the extractive distillation tower and a bottom liquid phase of the extractive distillation tower to obtain a dimethyl carbonate product; sequentially carrying out first reboiling, first flash evaporation, two times of heat exchange, second reboiling and second flash evaporation on the heat-exchanged bottom liquid phase of the extractive distillation tower to obtain a second flash evaporation gas phase and a second flash evaporation liquid phase; carrying out second heat exchange on the second flash liquid phase and the first flash liquid phase, condensing, and returning to the extractive distillation tower; and pressurizing the second flash evaporation liquid phase, performing third heat exchange with the first flash evaporation liquid phase after primary heat exchange, and condensing to obtain an ethanol product. The method is low in energy consumption, the solvent is not easy to volatilize, and the ethanol and the dimethyl carbonate in the azeotrope can be effectively separated.

The invention provides a ZIF-derived Co-P catalyst and a preparation method thereof. The catalyst can be used for synthesizing dimethyl carbonate through oxidative carbonylation of methanol. The ZIF-derived Co-P catalyst disclosed by the invention is prepared by roasting a precursor P-doped Zn / Co-ZIF intermediate. Compared with a traditional cobalt-based catalyst, the Co-P catalyst prepared through roasting treatment modification can regulate and control the variety and coordination number of heteroatoms, improve the interaction between metal and a carrier and effectively anchor metal atoms, and meanwhile P atoms can serve as second active sites to assist in improving the adsorption and activation capacity of reactants and intermediate species. In addition, the ZIF generates a hierarchical pore structure in the roasting treatment process, so that the mass transfer and diffusion processes of reactants and products are effectively promoted. According to the Co-P catalyst disclosed by the invention, the methanol oxidative carbonylation reaction activity is remarkably improved, and the catalyst has high stability.

The invention relates to the technical field of organic synthesis, in particular to a method for homogeneous catalytic synthesis of dimethyl carbonate by using a liquid separation method to separate a catalyst, which comprises the following steps: by using 0.3-15% long-chain tertiary amine as a homogeneous catalyst, carrying out homogeneous reaction on cyclic carbonate and methanol in a mass ratio of 1: (1.2-5.5) at 60-80 DEG C for 4-7 hours. And after the homogeneous transesterification reaction is completed, carrying out atmospheric distillation on the reaction mixture, and collecting fractions to obtain the target product dimethyl carbonate. Carrying out liquid separation on the heterogeneous atmospheric distillation residual liquid, and collecting a lower-layer material to obtain a by-product; and the collected material is a catalyst which can be directly recycled subsequently. The dimethyl carbonate synthesis method provided by the invention has the characteristics of high catalytic efficiency, easy catalyst separation, environmental protection, energy saving and the like.

The present invention discloses a method for upgrading polyester materials to dicarboxylic acid esters and ethylene carbonate, and relates to the comprehensive utilization of waste resources and the cascade utilization of raw materials. The method uses multiple types of green ionic liquid catalysts to catalyze the methanolysis reaction of PET, and then dimethyl carbonate captures the generated ethylene glycol in situ, forms a five-membered cyclic ethylene carbonate through nucleophilic cyclization, pulls the reaction equilibrium to move forward, and completely depolymerizes PET waste. The products of the method of the present invention are dimethyl terephthalate and five-membered cyclic ethylene carbonate. The present invention can be used for the depolymerization and upgrading of waste PET materials, and can also be used for other similar polyesters, such as polyethylene succinate, polyethylene adipate and polyethylene 2,5-furan dicarboxylate, which are also suitable for the recovery strategy of the present invention, and the products are the corresponding dimethyl succinate, dimethyl adipate and 2,5-furan dicarboxylate.

The invention belongs to the technical field of chemical production, and particularly relates to high-purity dimethyl carbonate and a preparation method thereof. The preparation method comprises the following steps: taking ethylene carbonate and methanol as raw materials, taking an alkali alcohol solution as a catalyst, carrying out transesterification in a rectifying tower to obtain dimethyl carbonate and methanol azeotrope, and extracting the azeotrope from the top of the rectifying tower; separating the dimethyl carbonate and methanol azeotrope by adopting pressurized azeotropic distillation to obtain a dimethyl carbonate crude product; and conveying the dimethyl carbonate crude product into a falling film crystallizer for continuous falling film crystallization, controlling the temperature of low-temperature chilled water in the falling film crystallizer to be-10 to 2 DEG C and the circulating material amount to be 3-5 times of the mass of the product required to be produced, and heating to melt the material to obtain the high-purity dimethyl carbonate product. According to the preparation method provided by the invention, rectification crude purification and continuous falling film crystallization processes are adopted, and dimethyl carbonate with the purity of 99.99% or above is obtained.

The invention belongs to the technical field of fine chemical preparation, and discloses a method for directly preparing dimethyl carbonate by catalyzing carbon dioxide and methanol through nano cerium oxide, which comprises the following steps: step S10, weighing nano cerium oxide, methanol and a deep eutectic solvent; s20, putting the weighed nano cerium oxide, methanol and the deep eutectic solvent into a beaker, and stirring and mixing; s30, adding the mixed solution into a reaction kettle, introducing carbon dioxide to replace air in the reaction kettle, and then heating the reaction kettle; s40, after the reaction kettle is cooled to the normal temperature, releasing the pressure and taking out the dimethyl carbonate; according to the scheme, by adding the deep eutectic solvent, water and a product in the reaction are separated, the reaction is promoted, homogeneous reaction and heterogeneous separation are realized, the highest conversion rate of methanol can reach 49.70%, and the selectivity of dimethyl carbonate exceeds 99%; the invention solves the problem of low conversion rate of the existing dimethyl carbonate preparation method.

The invention relates to the field of chemical synthesis, in particular to a production process of allyl diethylene glycol dicarbonate, which comprises the following steps: by taking allyl alcohol and dimethyl carbonate as raw materials, carrying out transesterification under the action of a core-shell catalyst to generate dipropylene carbonate; carrying out solid-liquid separation, carrying out reduced pressure distillation to recover methanol and dimethyl carbonate, and then carrying out second-step ester exchange reaction with diethylene glycol under the action of the same catalyst to generate allyl diethylene glycol dicarbonate; and finally, performing multi-stage reduced pressure distillation purification to obtain a high-purity product. According to the core-shell type catalyst, an MCM-41 molecular sieve is used as a carrier, an inner core is formed after amino modification and zirconium ion coordination, then an interface layer and a phenyl modified silicon dioxide shell are used for packaging, and the core-shell type catalyst has high activity, high selectivity and excellent structural stability. The method has the advantages of mild process conditions, recyclable catalyst, high product yield and excellent purity, and is suitable for industrial production.

The invention belongs to the technical field of copolymerization modification of degradable polyester, and relates to a depolymerization method and application of polybutylene terephthalate. During depolymerization, polybutylene terephthalate, dimethyl carbonate and dihydric alcohol are mixed and then subjected to a depolymerization reaction, and an intermediate ester is prepared; the dihydric alcohol is dihydric alcohol which does not form a ring with dimethyl carbonate in the depolymerization reaction process; the molar weight of the dimethyl carbonate is 10-30% of the molar weight of a repetitive unit of the polybutylene terephthalate; the sum of the molar weight of a 1, 4-butanediol unit in the polybutylene terephthalate and the molar weight of the added dihydric alcohol is a, the sum of the molar weight of a terephthalic acid unit in the polybutylene terephthalate and the molar weight of the added dimethyl carbonate is b, and the ratio of b to a is (1.2-1.5): 1; during application, the prepared intermediate ester is subjected to transesterification under the condition of negative pressure to obtain the copolyester. The depolymerization method is simple and easy to implement; the depolymerization product can be directly applied.

The invention relates to the technical field of plastic surface treatment, in particular to an environment-friendly novel plastic brightening cleaning agent formula and a preparation method and application thereof. The formula consists of 25-35% of a high-polarity compound propylene carbonate, 5-15% of a moderate-polarity compound ethyl acetate and 55-65% of a low-polarity compound dimethyl carbonate according to a specific weight ratio, and during preparation, under the protection of nitrogen, the three components are stirred for 20-30 minutes at the temperature of 20-30 DEG C at the speed of 200-400 rpm, and are sealed in an HDPE (High-Density Polyethylene) barrel after being filtered by 0.5 mu m. The bright cleaning agent has low toxicity (VOCsilt; 50 g / L), rapid volatilization (the surface drying time is less than or equal to 3 minutes) and high biodegradability (gt; the sulfate crystals of the lead-acid storage battery shell can be efficiently removed (the wiping removal rate after spraying is gt; and moreover, the glossiness is obviously improved to be more than or equal to 85 GU (an incidence angle of 60 degrees). The method is simple in process, meets the international environmental protection standard (such as GB 38508-2020), is suitable for industrial production and multi-scene application, has efficient cleaning and environmental protection safety, and is suitable for industrial production and multi-scene application.

The invention discloses a catalyst for preparing isosorbide, a preparation method of the catalyst and a method for preparing isosorbide through reaction of sorbitol and dimethyl carbonate. The catalyst for preparing the isosorbide comprises macroporous ion exchange resin, and the macroporous ion exchange resin is provided with spherical or sphere-like pore channels and comprises a styrene type resin matrix and functional groups, the functional group is derived from a product obtained by carrying out chloromethylation on the styrene type resin matrix and then reacting the chloromethylated styrene type resin matrix with a heterocyclic compound containing more than two N atoms and a derivative of the heterocyclic compound. The catalyst can efficiently catalyze the reaction of sorbitol and dimethyl carbonate to prepare isosorbide, and has the characteristics of easy separation and high selectivity.

The invention discloses a polysilsesquioxane / polyether-ether-ketone composite membrane, a preparation method thereof and application of the polysilsesquioxane / polyether-ether-ketone composite membrane in organic mixed solvent separation, and aims to solve the problem of large-area deposition of a defect-free polysilsesquioxane hybrid membrane on a polymer substrate in the prior art. According to the present invention, the 1, 2-bis (triethoxysilyl) ethane polysilsesquioxane precursor is adopted as the raw material to prepare the membrane material, the new membrane preparation method is provided, the processing process is designed and optimized from the aspects of the simplicity and convenience of the membrane preparation process, the industrialization of the membrane separation technology, the improvement of the membrane preparation efficiency and the like, the membrane preparation efficiency is improved, and the certain separation performance is provided; the method has an excellent effect on separation and recovery of methanol / toluene and methanol / dimethyl carbonate.

The invention discloses a high-selectivity pyridine alkylation method which comprises the following steps: taking anhydrous titanium chloride and an anhydrous ferric chloride solution as raw materials, adding a dispersing agent, heating and uniformly stirring, adding ammonia water to adjust the pH value to a fixed value, grinding and sieving to obtain a catalyst carrier; dipping the catalyst carrier into a rare earth metal oxide solution dissolved by dilute sulphuric acid in an equivalent volume manner, aging, grinding and sieving to obtain a rare earth metal modified solid superacid catalyst; the method comprises the following steps: activating a rare earth metal modified solid superacid catalyst, cooling to a reaction temperature, filling a fluidized bed reaction tube with the catalyst, mixing pyridine and dimethyl carbonate, starting feeding, opening an air inlet valve, introducing nitrogen, and carrying out a reaction on the raw material mixed nitrogen in a catalyst layer to realize high-selectivity pyridine alkylation. Pyridine and a green methylation reagent dimethyl carbonate are used as raw materials, and high-selectivity synthesis of 2-methylpyridine can be realized under the action of a rare earth metal modified solid superacid catalyst.

The invention aims to provide a preparation method and application of a catalyst containing vacancy cluster ultrathin CeO2 nanosheets, and belongs to the technical field of catalyst preparation.The preparation method comprises the steps that cerium nitrate hexahydrate is used as a cerium source, pyromellitic acid is used as a ligand, deionized water is used as a solvent, polyvinylpyrrolidone is used as a surface active agent, and the vacancy cluster ultrathin CeO2 nanosheets are prepared; preparing a two-dimensional Ce-MOFs precursor at 70 DEG C by adopting a simple hydrothermal method; secondly, the two-dimensional Ce-MOFs precursor is roasted for 5 h in the air atmosphere, and the vacancy cluster ultrathin CeO2 nanosheet containing catalyst is obtained. The catalyst containing the vacancy cluster ultrathin CeO2 nanosheets has a remarkable influence on the activity of catalyzing CO2 / CH3OH to prepare dimethyl carbonate, and a new research idea is provided for preparation of an efficient cerium-based catalyst and synthesis of dimethyl carbonate.

The invention belongs to the field of energy storage, and particularly discloses a battery and a liquid injection method thereof, an energy storage device and a power utilization system.The battery comprises a positive pole piece, a negative pole piece, a diaphragm and electrolyte, the diaphragm is arranged between the positive pole piece and the negative pole piece, and the electrolyte comprises free electrolyte and non-free electrolyte; the non-free electrolyte comprises an electrolyte in the pores of the positive pole piece, an electrolyte in the pores of the negative pole piece and an electrolyte in the pores of the diaphragm; the free-state electrolyte comprises dimethyl carbonate, the mass ratio of the dimethyl carbonate in the free-state electrolyte is m1%, the non-free-state electrolyte comprises dimethyl carbonate, the mass ratio of the dimethyl carbonate in the non-free-state electrolyte is m2%, and the requirement that the mass ratio of the dimethyl carbonate in the non-free-state electrolyte is-5lt is met; m < 1 >-m < 2 > lt; 20 < = m1 < = 45, and 30 < = m2 < = 50.

The present application relates to the technical field of lithium-ion batteries, and specifically relates to a cylindrical lithium-ion battery having improved high-temperature storage performance and high-temperature cycle performance. The cylindrical lithium-ion battery comprises a positive electrode, a negative electrode and a non-aqueous electrolyte solution, wherein the negative electrode comprises a negative electrode material layer containing a negative electrode active material, the negative electrode active material comprising a silicon-based material; and the non-aqueous electrolyte solution comprises a lithium salt, an organic solvent and an additive, the organic solvent comprising dimethyl carbonate, and the additive comprising a silane compound represented by structural formula 1. The cylindrical lithium-ion battery satisfies the following condition: 0.04≤(100-D)×F / S≤5, wherein 50≤D≤75, 0.01≤F≤0.5, and 5≤S≤20. In the cylindrical lithium-ion battery of the present application, the electrolyte solution contains the silane compound represented by structural formula 1 as an additive and dimethyl carbonate as the organic solvent, and therefore the problem of battery failure caused by the expansion of the silicon-based negative electrode can be improved, the service life of the battery can be prolonged, the battery is ensured to have good high-temperature performance, and the effect of inhibiting gas production during high-temperature storage is obvious.

The application provides a battery monomer, a battery device and a power utilization device. The battery monomer comprises a positive electrode sheet, a separator, a negative electrode sheet and an electrolyte. The positive electrode sheet and the negative electrode sheet are stacked, and the separator is arranged between the positive electrode sheet and the negative electrode sheet. The positive electrode sheet comprises a positive electrode main body part and a positive electrode tab part. The ratio of the long side size to the short side size of the positive electrode main body part is (3-8):1. The negative electrode sheet comprises a negative electrode main body part and a negative electrode tab part. The long side of the negative electrode main body part exceeds the long side edge of the positive electrode main body part by 2-9 mm. The long side of the separator exceeds the long side edge of the negative electrode main body part by 2-10 mm. The electrolyte comprises a solvent. The solvent comprises one or more of dimethyl carbonate and a linear carboxylic acid ester having a structure shown in formula (1). In formula (1), R1 and R2 each independently comprises a C1-C5 alkyl or a halogenated alkyl. The battery monomer has a high energy density, good cycle performance and low self-discharge.

According to the method, industrial-grade 1, 2-propylene glycol co-produced by a dimethyl carbonate process through a transesterification method is taken as a raw material, and purification processes of activated carbon adsorption impurity removal, deodorant impurity removal and rectification impurity removal are carried out, so that various indexes such as chromaticity, odor, purity and ultraviolet light transmittance of the obtained 1, 2-propylene glycol product reach the quality indexes of an imported pharmaceutical-grade 1, 2-propylene glycol product. According to the method disclosed by the invention, the pharmaceutical grade propylene glycol can be prepared with high quality, and a good development prospect and huge economic benefits are undoubtedly brought to the propylene glycol industry.

The invention relates to the technical field of printing materials, in particular to an environment-friendly silk-screen printing ink diluent based on propylene carbonate and dimethyl carbonate, which comprises dimethyl carbonate and propylene carbonate, and the dimethyl carbonate and the propylene carbonate are compounded according to a certain proportion. The diluent further comprises a synergistic solvent and a functional additive which are added according to a certain proportion. The environment-friendly silk-screen printing ink diluent formula for silk-screen printing ink and the preparation method of the environment-friendly silk-screen printing ink diluent formula are particularly suitable for viscosity adjustment and printability optimization of solvent type oil black, have the characteristics of low volatility and high solubility, and solve the problems of high toxicity of a traditional solvent, poor stability of a compound system, insufficient printability and the like.

The present application relates to the field of environmental protection additives, specifically disclosing a natural gas low-temperature combustion-supporting environmental protection additive and its preparation method. The natural gas low-temperature combustion-supporting environmental protection additive comprises the following substances in parts by weight: 10 to 50 parts of dimethyl carbonate, 0 to 10 parts of methyl tert-butyl ether, 10 to 20 parts of methanol, and 15 to 20 parts of dispersed catalytic particles; the dispersed catalytic particles are carbon aerogels adsorbed with nano-Pt particles. The natural gas low-temperature combustion-supporting environmental protection additive of the present application uses dimethyl carbonate, methyl tert-butyl ether, and methanol as liquid matrices, and a carbon aerogel material adsorbed with the precious metal Pt as a catalytic material. The environmental protection additive material is effectively coated and loaded in the boiling gas phase. A uniform bonding form is formed between the gas-phase environmental protection additive and the natural gas, so that the methane in the natural gas opens the gas-hydrogen-oxygen bond under the action of the environmental protection additive at 80 to 100°C, effectively catalyzing the combustion of natural gas in an oxygen-rich state, further improving the activity of natural gas in a low-temperature environment.

The invention provides a low-energy-consumption preparation process of tetramethylammonium bicarbonate, and relates to the technical field of chemical synthesis. The preparation process comprises the following steps: inputting trimethylamine, dimethyl carbonate and a solvent methanol into a reactive distillation tower, carrying out a quaternization reaction to generate methyl carbonate tetramethylammonium, and carrying out a hydrolysis reaction on a first liquid phase obtained by rectification and water vapor to generate TMAB; the reacted material is input into a methanol removal tower for rectification, an obtained second gas phase is heated and pressurized, one part of the second gas phase is input into a subsequent methanol recovery tower, the other part of the second gas phase exchanges heat with water to generate steam, the steam is input into a tower kettle of the methanol removal tower, and high-purity methanol is extracted from the side of the methanol recovery tower. The number of reaction equipment is reduced, and the energy utilization rate is increased; the steam grade is improved by utilizing a heat pump technology, and steam latent heat is integrated between the methanol removal tower and the methanol recovery tower through thermal coupling, so that the overall process energy consumption is remarkably reduced while the product quality is ensured.

The invention discloses a preparation process of a cefpodoxime mother nucleus 7-AMCA, and relates to the technical field of 7-AMCA. According to the technical scheme, the method comprises the following steps: adding dimethyl carbonate and a boron trifluoride-dimethyl carbonate complex into a reaction bottle A, and dropwise adding an alkylation reagent; adding D-7ACA, and reacting at room temperature; adding purified water, sodium pyrosulfite and edetate disodium into the reaction bottle B; transferring the feed liquid in the reaction bottle B into a reaction bottle A, adding an organic solvent into the mixed liquid at room temperature, and extracting and separating the liquid to obtain a water phase; dropwise adding an alkaline solution into the water phase, adjusting the pH value to 2.8-3, and cooling to grow crystals; dropwise adding an alkaline solution, adjusting the pH value to 4.5-5.2, and cooling to grow crystals; and filtering out mother liquor, washing to be colorless, leaching by using an organic solvent, pumping, and drying in vacuum to obtain the cefpodoxime mother nucleus 7-AMCA. According to the invention, D-7ACA is taken as a starting raw material, the process flow is improved, the preparation process of 7-AMCA is optimized, and the purposes of improving the product quality and increasing the yield are achieved.

The invention relates to preparation of a cefazolin compound, in particular to a preparation method of a cefazolin acid three-position intermediate TDA. The preparation method comprises the following steps: carrying out condensation reaction on 7-ACA and MMTD serving as raw materials, dimethyl carbonate serving as a solvent and a boron trifluoride dimethyl carbonate complex and glacial acetic acid serving as catalysts to obtain condensation reaction liquid; adding EDTA (Ethylene Diamine Tetraacetic Acid) and sodium pyrosulfite into water, carrying out stirring reaction, transferring the condensation reaction liquid into water, and continuously carrying out heat-preservation stirring, so as to obtain a hydrolysis reaction liquid; and adding a sodium carbonate solution into the hydrolysis reaction solution while stirring, adjusting the pH value, growing crystals, and then performing suction filtration, washing and drying to obtain a finished product. A boron trifluoride dimethyl carbonate complex-glacial acetic acid catalysis method is adopted, the product quality and yield are guaranteed in industrial production, meanwhile, the reagent usage amount and the waste liquid generation amount are reduced, the production cost and the environment pressure are reduced, normal reaction is maintained at normal pressure, and the reaction is prevented from being too severe.

The invention provides a battery monomer and a preparation method thereof, a battery device and a power utilization device, the battery monomer comprises a positive pole piece, an isolating membrane, a negative pole piece and an electrolyte, the positive pole piece and the negative pole piece are laminated, and the isolating membrane is arranged between the positive pole piece and the negative pole piece; the positive pole piece comprises a positive pole main body part and a positive pole lug part, and the ratio of the long side size to the short side size of the positive pole main body part is (3-8): 1; the isolating membrane comprises a base membrane and a bonding layer arranged on at least one side of the base membrane, and the bonding layer is a continuous layer of a porous structure; the electrolyte comprises a first solvent, and the first solvent comprises one or more of dimethyl carbonate and linear carboxylic ester with a structure as shown in a formula (1); in the formula (1), R1 and R2 respectively and independently comprise C1-C5 alkyl or halogenated alkyl. The battery monomer has relatively high energy density, relatively good cycle performance and relatively low self-discharge.

The invention relates to a battery monomer, a battery device and a power utilization device, the battery monomer comprises an electrode assembly and an electrolyte, and the volume average particle size Dv50 of graphite particles of a negative electrode active material layer is 7.8-12.5 [mu] m; the electrolyte comprises a carboxylic ester solvent with the mass content of 8%-30%, a cyclic carbonate solvent with the mass content of 25%-35% and a linear carbonate solvent with the mass content of 18%-45%, and the linear carbonate solvent comprises dimethyl carbonate, an unsaturated ester additive with the mass content of 0.05%-5% and a lithium salt additive with the mass content of 0.2%-1.5%; the amount of electrolyte in the battery cell is 2.8 g / Ah to 3.2 g / Ah. According to the invention, rapid charging and use reliability of the single battery can be considered.