13results about How to "Low purity requirement" patented technology

The invention provides a method for preparing high-purity lithium sulfide from lithium carbonate, and belongs to the technical field of lithium material preparation, and the method comprises the following steps: heating a ball-milled mixture of industrial-grade lithium carbonate and an alumina additive to 750-900 DEG C, and carrying out heat preservation and calcination to generate lithium oxide; performing hydrolysis reaction on lithium oxide in hot water, and filtering to obtain a high-purity lithium hydroxide solution; mixing the lithium hydroxide solution with the sulfur-containing protein, and performing spray drying to obtain a mixed precursor; calcining the mixed precursor at a low temperature of 210-340 DEG C in an inert atmosphere; and heating to 550-660 DEG C, calcining at a high temperature, introducing hydrogen sulfide gas, reacting lithium hydroxide to generate lithium sulfide, and cooling to obtain the high-purity lithium sulfide. The invention provides the method for preparing the high-purity lithium sulfide, the purity, the production efficiency and the raw material utilization rate of the lithium sulfide are remarkably improved, and the technical defects of low purity, incomplete raw material reaction, non-uniform precursor mixing, complicated process, difficulty in large-scale production and the like in the traditional lithium sulfide preparation method are overcome.

The present invention provides a methanol reforming hydrogen production and power generation system, including a liquid inlet module, a methanol water reforming hydrogen production module, a power generation module, a stack heat dissipation module and an electronic control module. The methanol reforming hydrogen production and power generation system of the present invention adopts a hydrogen-rich stack, which reduces the purity requirements of the hydrogen entering the stack; secondly, the system adopts selective catalytic technology, and as long as the temperature required by the design is reached, it can produce hydrogen that meets the requirements of the hydrogen-rich stack. The structural design is simple, reducing the pressure required to be borne by the palladium tube, thereby reducing the production process requirements; in addition, an inverter is added inside the system, which can boost the electric energy generated by the stack to adapt to the applicable scope of the mains power usage scenario; energy storage batteries are also added inside the system, which can realize power generation without an external power supply.

This invention provides the application of a mixture of methylstyrene with high para-isomer content in the preparation of polystyrene substitute copolymers, belonging to the field of polymer material synthesis technology. This invention is the first to directly utilize a low-cost mixture of methylstyrene isomers to replace high-purity styrene. Through a "boiling-condensation" cycle in the fluidized bed polymerization process, efficient and constant-temperature heat dissipation is achieved, effectively overcoming the heat transfer difficulties and temperature runaway risks of traditional bulk polymerization. This facilitates control of the polymerization mechanism and yields random copolymers with a narrow molecular weight distribution and mechanical properties comparable to general-purpose polystyrene. This method is simple and controllable, significantly reduces raw material costs, and combines economic benefits with environmental value. The resulting copolymers can be used in general plastics, packaging materials, and other fields.

The application relates to a purification method of a bifluorosulfonylimide lithium salt, comprising the following steps: modifying a polytetrafluoroethylene film by using plasma and formic acid, immersing the polytetrafluoroethylene film in bifluorosulfonylimide acid after the modification is completed, heating and drying to obtain a modified polytetrafluoroethylene film; dispersing lithium carbonate in dimethyl carbonate, then adding bifluorosulfonylimide acid, obtaining a reaction liquid after the reaction is completed, filtering the reaction liquid to obtain a filtrate, concentrating the filtrate once to obtain a bifluorosulfonylimide lithium electrodialysis crude solution; using the modified polytetrafluoroethylene film to purify the bifluorosulfonylimide lithium electrodialysis crude solution by electrodialysis, then concentrating and crystallizing the obtained electrodialysis liquid to obtain battery-grade bifluorosulfonylimide lithium. The method provided by the application can reduce the purity requirement of raw material lithium carbonate from battery grade to industrial grade, which is beneficial to industrial production.

The invention relates to the technical field of chemical materials, and discloses a preparation method of an anti-yellowing agent HN-130, which comprises the following steps: respectively dissolving hexamethylene diisocyanate and unsymmetrical dimethylhydrazine in a solvent to prepare a hexamethylene diisocyanate-solvent mixed solution and an unsymmetrical dimethylhydrazine-solvent mixed solution; dropwise adding the hexamethylene diisocyanate-solvent mixed solution into the unsymmetrical dimethylhydrazine-solvent mixed solution at a set temperature, and meanwhile, keeping constant temperature and continuously stirring until the hexamethylene diisocyanate-solvent mixed solution and the unsymmetrical dimethylhydrazine-solvent mixed solution are fully reacted; the method provided by the invention has low requirements on the purity of raw materials, wherein the purity of unsymmetrical dimethylhydrazine is greater than or equal to 90%; the method provided by the invention is simple in process and high in operability; the solvent can be recycled, and the solvent purification process is simple and wide in application range; compared with the existing synthesis process, the anti-yellowing agent HN-130 prepared by the method provided by the invention has the advantages of high yield, high product purity and low chromaticity.

The present invention belongs to the technical field of preparation of carbide materials, and discloses a method for preparing β-SiC powder, comprising the following steps: adding blue charcoal, water glass, an organic acid and a metal salt to water, mixing evenly, and then hydrothermally treating at a constant temperature of 100-200°C for 1-10h to obtain a carbon-silicon composite precursor; placing the carbon-silicon composite precursor under an argon atmosphere, performing a carbon thermal reduction reaction, obtaining a reaction product, and purifying the reaction product to obtain β-SiC powder. The present invention uses a hydrothermal method to fully crosslink and mix water glass and blue charcoal at a molecular scale to form a carbon-silicon composite precursor composite, thereby significantly improving the yield of silicon carbide, and since the present method can achieve the mixing of raw materials at a molecular scale, the requirements for raw material purity can be reduced. In the crosslinking mixing process, an organic acid is added to neutralize the alkaline substances in the water glass, reduce equipment corrosion, and increase the service life of the equipment.

The present invention discloses a preparation method of polyglycolic acid and the obtained polyglycolic acid, wherein the preparation method comprises: reacting raw materials including glycolide, a catalyst and an acid anhydride additive to obtain polyglycolic acid. The present invention introduces an acid anhydride additive to convert the hydroxyl functional groups in the impurities that affect polymerization into carboxyl functional groups that have little effect on polymerization, thereby reducing the requirements for the purity of glycolide, and obtaining high-viscosity PGA, thereby reducing the cost and further broadening the application range of PGA.

The application discloses a RAPD molecular marker primer for identifying the gender of Momordica grosvenori. The nucleotide sequence of the RAPD molecular marker primer is ACAGCCTGCT. The application discloses a kit containing the RAPD molecular marker primer for identifying the gender of Momordica grosvenori and application thereof. The application also discloses a method for identifying the gender of Momordica grosvenori by using the RAPD molecular marker primer. The method comprises the following steps: performing PCR amplification on total DNA of Momordica grosvenori by using the RAPD molecular marker primer, performing electrophoresis to obtain corresponding bands, and then identifying the gender of Momordica grosvenori. The RAPD molecular marker primer provided by the application is a random primer, has high specificity for male plants, can efficiently and rapidly distinguish male plants from female plants of Momordica grosvenori, and has the advantages of small DNA dosage, low purity requirement, simple experimental process, fast working progress and low cost in the identification test.

This invention discloses a method for preparing polyglycolic acid (PGA) and the PGA obtained by this method, relating to the field of PGA preparation technology. The method comprises: prepolymerizing glycolide in the presence of a catalyst to obtain a suspension; separating and removing insoluble matter from the suspension; and then performing a polymerization reaction to obtain the PGA. This invention uses low-purity glycolide as a raw material. After adding a catalyst, impurities undergo a certain degree of prepolymerization at a low temperature, allowing them to precipitate automatically. The precipitate is then separated and removed to obtain high-purity glycolide, which is then polymerized in situ at a higher temperature (retaining the initially added catalyst) to obtain high-molecular-weight PGA. This preparation method has low requirements for raw material purity, is simple and effective, and reduces the cost of PGA preparation to a certain extent.

The invention discloses a device for producing nano C-S-H based on a narrow-gap electrolytic bath and a preparation method.The device comprises an electrolytic bath assembly, the electrolytic bath assembly comprises an acid reaction liquid bin, an alkaline reaction liquid bin, a separation membrane and a bipolar plate, and the acid reaction liquid bin and the alkaline reaction liquid bin are separated through the separation membrane; the two bipolar plates are used for clamping and fixing the reaction liquid bin and the separation membrane; the at least two electrolytic cell assemblies are connected in series; the electrolysis assembly provides electric energy for the electrolytic tank assembly; the acid liquor tank is connected with each acid reaction liquid bin; the alkali liquor pool is connected with each alkaline reaction liquid bin; electrolyte in the precipitation reaction tank, the acid liquor tank and the alkali liquor tank flows to the precipitation reaction tank. According to the device, the contact area of the acidic electrolyte and the alkaline electrolyte is increased through the plurality of electrolytic bath assemblies connected in series, and the distance between the acidic reaction liquid bin and the alkaline reaction liquid bin is closer so as to improve the electrolytic efficiency; in addition, the requirement for the purity of calcium minerals and siliceous minerals is not high, and dependence on high-purity raw materials is avoided.

The invention discloses a method for removing high-concentration nitrates in wastewater, wherein the iron powder after pickling is put into the wastewater containing nitrates together with nitrite and copper ion for stirring reaction, and sulfuric acid is continuously added to control the pH value of the reaction solution to 3-5, and the reaction is stirred under room temperature and anaerobic conditions. After the reaction is completed, solid-liquid separation is performed, and the supernatant after separation is discharged as qualified wastewater, and the solid is reused for further processing of nitrate wastewater. The reductive iron powder used in the present invention has low purity requirements, and the pharmaceutical cost required for the process is relatively low; the iron powder can be recycled 1-3 times; (2) the efficiency in the treatment of high-concentration nitrate wastewater is relatively high, higher than 50% of the existing method, reaching 98%; (3) the ratio of the harmless gas nitrogen produced is relatively high.

The present application relates to a kind of poly-doped-ammonium intercalation vanadium oxide material and its preparation method and purposes, the preparation method includes the following steps: (1) the alkali leaching solution of sodium calcined vanadium residue is added to desilication agent and carries out desilication reaction, obtains desilication leaching solution;(2) the desilication leaching solution in step (1) is added to ammonium salt and carries out precipitation reaction, obtains precursor;(3) the precursor in step (2) is sequentially carried out drying treatment, calcination treatment, and the poly-doped-ammonium intercalation vanadium oxide material is prepared.The preparation process of the present application reduces the requirement for vanadium species purity in preparation process on the one hand by using the alkali leaching solution of vanadium residue as raw material, on the other hand, the associated excellent impurities therein serve as a doping source for the preparation process, making the preparation process more simplified, and the zinc ion battery prepared from the obtained vanadium oxide material has excellent electrochemical performance.

The application belongs to the field of new energy, and discloses a synthesis method of lithium tetrafluoroborate, which comprises the following steps: step 1: adding lithium halide into a non-aqueous organic solvent, and introducing boron trichloride to obtain a solution containing lithium haloborate; and step 2: introducing hydrogen fluoride into the solution obtained in step 1 to obtain a solution containing lithium tetrafluoroborate. The method is synthesized by using a solvent method, and any available lithium halide and boron trichloride are used to react to obtain an intermediate product, and then the intermediate product is fluorinated to obtain lithium tetrafluoroborate, and various lithium halides can be selected to realize the scheme of the application, the raw materials are rich in selectivity, and the production cost is significantly reduced.