1338 results about "Methyl carbonate" patented technology

The invention relates to a carrier type solid base catalyst for synthesizing dimethyl carbonate, which belongs to the technical field of catalytic material. The catalyst's formula is KF / M<2+>-N<3+>-(O), wherein M<2+>-N<3+>-(O) represents the composite metal oxide, M<2+> can be divalent metal ion (Mg<2+> or Ca<2+> ) and N<3+> can be trivalent metal ion (Fe<3+> and / or Al<3+>). The catalyst is prepared from potassium fluoride and composite metal oxide at a certain weight ratio by immersing the potassium fluoride into the composite metal oxide, wherein the composite metal oxide is prepared from hydrotalcite precursor and in nucleation / crystallization isolation method by calcining at a certain temperature. The catalyst has the advantages of nanoscaled particle size, high specific surface area and high activity, selectivity in catalytic reaction and simple preparation, and can be reused as it can be centrifugally separated after reacting.

The invention discloses a non-aqueous electrolyte for a lithium iron phosphate battery. The non-aqueous electrolyte comprises 70 to 85 weight percent of carbonic ester compound, 3 to 20 weight percent of various function additives and 11 to 17 weight percent of lithium hexafluorophosphate, wherein the carbonic ester compound is one of ethylene carbonate, propylene carbonate, butylene carbonate, dimethyl carbonate and diethyl carbonate or a mixture of more of the ethylene carbonate, the propylene carbonate, the butylene carbonate, the dimethyl carbonate and the diethyl carbonate; and the additives comprise one of 0.5 to 10 percent of film-forming additive, 0.5 to 10 percent of high-temperature additive, 0.5 to 10 percent of low-temperature additive, 0.5 to 10 percent of overcharge-preventing additive and 0.001 to 2 percent of stability additive, and a mixture of more of the additives. The non-aqueous electrolyte for the lithium iron phosphate battery has the advantages that the solubility and dissociation of the lithium hexafluorophosphate are improved, and electric conductivity is improved; the low temperature resistance of a solid electrolyte interphase (SEI) is reduced; the overall stability of the battery is improved, the overall service life of the battery is prolonged, the compatibility of an electrolyte and a cathode is improved, circulation of the battery is improved, and the service life is prolonged; and the non-aqueous electrolyte can have high performance at high temperature.

The metal oxide catalyst for urea alcoholysis process of synthesizing methyl carbonate consists of 1-3 kinds oxides of Li, Mg, Ni, Zn, Pb, Al, Fe, Mo, Zr and La, and has ZnO as main component accounting for 35-95 wt%. When it consists of three kinds of metal oxide, the other two except ZnO have the same weight percentage. It is prepared through thermal decomposition process, precipitation process, or coprecipitation process. The catalyst is easy to prepare, separate, recover and regenerate, and has high catalytic activity for urea alcoholysis process of synthesizing methyl carbonate, yield up to 49.7%, no corrosion of equipment and no environmental pollution.

The invention discloses various embodiments of Li-ion electrolytes containing flame retardant additives that have delivered good performance over a wide temperature range, good cycle life characteristics, and improved safety characteristics, namely, reduced flammability. In one embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a fluorinated co-solvent, a flame retardant additive, and a lithium salt. In another embodiment of the invention there is provided an electrolyte for use in a lithium-ion electrochemical cell, the electrolyte comprising a mixture of an ethylene carbonate (EC), an ethyl methyl carbonate (EMC), a flame retardant additive, a solid electrolyte interface (SEI) film forming agent, and a lithium salt.

A lithium ion electrochemical cell having high charge / discharge capacity, long cycle life and exhibiting a reduced first cycle irreversible capacity, is described. The stated benefits are realized by the addition of at least one carbonate additive to an electrolyte comprising an alkali metal salt dissolved in a solvent mixture including ethylene carbonate, dimethyl carbonate, ethyl methyl carbonate and diethyl carbonate. The preferred additive is either a linear or cyclic carbonate containing covalent O-X and O-Y bonds on opposite sides of a carbonyl group wherein at least one of the O-X and the O-Y bonds has a dissociation energy less than about 80 kcal / mole.

The invention provides a method for preparing ethyl methyl carbonate through an ester exchange method, and relates to a method for preparing a chemical raw material. A first catalyst prepared by the method simultaneously has macropore and micropore structures, wherein the macropores can obviously improve the mass transfer effect; and the micropores can obviously improve the specific surface area of a carrier and simultaneously improve the dispersity of active centers. Meanwhile, the prepared first catalyst simultaneously has an alkali active center and a Lewis acid catalytic active center. The prepared 15%MgO-5%MgCl2-2%La2O3 / Al2O3-SiO2 is used in a dimethyl carbonate and ethanol ester exchange fixed bed continuous reaction; when the reaction temperature is 200 DEG C and the space velocity is 30h<-1>, the catalyst is not inactivated after 5000h of continuous reaction, the dimethyl carbonate conversion rate can be kept at 70%, the ethanol conversion rate can be kept at 80%, and the yield of the product ethyl methyl carbonate is 56%; and after the reaction, the catalyst can be reused through simple filtration treatment, and the activity of the catalyst can still be kept unchanged after the catalyst is reused for multiple times.

The invention discloses a lithium-ion secondary battery and a manufacturing method thereof. The lithium-ion secondary battery comprises an anode material, a cathode material, a diaphragm and electrolyte, wherein, the anode material and the cathode material are coated in a metal casing, the diaphragm is arranged between the anode material and the cathode material, and the electrolyte is filled in the diaphragm; the anode material is prepared by mixing a Ni-Co-Mn ternary material with a lithium manganate material base on a proportion of 1-9:9-1 by weight parts; the cathode material is made of graphite; the electrolyte is prepared by mixing ethylene carbonate, dimethyl carbonate with methyl ethyl carbonate based on the volume ratio of 1:1:1; and the diaphragm is porous polypropylene, polyethylene or a modified polymer of the porous polypropylene and the polyethylene. The invention has the advantages of excellent safety performance, least production cost and larger specific capacity, and through safety tests such as overcharge, over-discharge, short circuit, needling, extrusion, heavy impact, hot box and the like, the safety performance meets the standard testing requirements of UL1642, IEC60949-3 and GB / T18287-2004, and products meet the requirements and reach RoHS instruction requirement.

The invention belongs to the technical field of medicaments, and provides application of a cleavable polyethylene glycol (PEG) lipid derivative to preparation of a PEGylated preparation for relieving or avoiding accelerated blood clearance. In the application, liquid microparticle preparations such as liposome, vesicles, emulsions, microemulsion, micelles, nanoparticles and the like are modified by the cleavable PEG lipid derivative such as PEG-cholesteryl hemisuccinate, PEG-cholesteryl methyl carbonate, PEG-alpha tocopheryl hemisuccinate and the like; and the measurement of variation of preparation elimination in tissues such as animal blood plasma, liver, spleen and the like after a cleavable PEG lipid derivative-modified medicinal preparation is repeatedly injected proves that repeated injection of cleavable PEG lipid derivative-modified microparticle preparations only causes light accelerated blood clearance or avoids the accelerated blood clearance, namely the accelerated blood clearance can be relieved or avoided. The invention discloses new application of the cleavable PEG lipid derivative.

The invention relates to the field of fuels, and discloses smokeless diesel oil and a preparation method thereof. The smokeless diesel oil comprises 70-95wt% of common diesel oil, 2-25wt% of dimethyl carbonate and 0-10wt% of a multifunctional compound additive. According to the smokeless diesel oil provided by the invention, particulate matter emission in the using process of means of conveyance (comprising various motor vehicles and ships) taking diesel oil as a fuel and machinery for engineering, mining and agriculture and forestry taking diesel engines as power can be greatly reduced or even eliminated without affecting other emission indexes. The smokeless diesel oil is clean and environment-friendly diesel oil, and is simple and convenient and feasible. The fuel system of the diesel engine needs not to be changed.