9results about How to "Increase true density" patented technology

The invention belongs to the technical field of inorganic powder, and discloses low-radioactivity spherical aluminum oxide as well as a preparation method and application thereof. The preparation method comprises the following steps: adopting ultrapure water at 20-60 DEG C, and adding acid to adjust the pH value to be less than or equal to 2.5 to obtain acid liquor; taking aluminum hydroxide / boehmite / industrial alumina as raw materials, adding the raw materials into the acid liquor, and stirring and dispersing to obtain mixed slurry A; adding alkaline anion exchange resin into the mixed slurry A, carrying out hydrothermal stirring treatment for 8-12 hours, and removing the alkaline anion exchange resin to obtain mixed slurry B; carrying out suction filtration and drying on the mixed slurry B, and carrying out heat preservation treatment on the dried material at 1300-1400 DEG C for 6-9 hours; and S4, crushing and dispersing the material subjected to heat preservation treatment in the step S4, and melting and spheroidizing at 1100-1300 DEG C to obtain a low-radioactivity spherical aluminum oxide crude product. The prepared low-radioactivity spherical alumina powder is compact in structure, high in thermal conductivity, low in uranium content and suitable for EMC production and application.

This invention provides a method and system for producing needle coke from ethylene tar. The method includes the following steps: (1) ethylene tar feedstock is mixed with hydrogen-containing gas and then enters a hydrogenation reaction zone, where it is reacted sequentially with at least two hydrogenation catalyst beds; (2) the reaction effluent obtained in step (1) is separated into gaseous and liquid phase products; (3) the liquid phase product obtained in step (2) enters a coking unit, and the oil and gas generated in the reaction are separated to obtain gas, light component oil, middle distillate oil, and heavy distillate oil. After the reaction cycle is completed, the final needle coke product is obtained. In the hydrogenation reaction zone mentioned in step (1), compared with the hydrogenation catalyst in the adjacent upstream hydrogenation catalyst bed, the proportion of mesopores >30nm in the downstream hydrogenation catalyst bed is reduced, and the proportion of mesopores <5nm in the upstream hydrogenation catalyst bed is increased. The method can suppress the formation of coking precursors and produce high-quality needle coke products.

The application discloses a prebaked anode, characterized in that the raw material for preparing the prebaked anode comprises aggregate and binder, wherein the aggregate comprises calcined petroleum coke and / or coal-based coke, and the binder comprises low-ash high-caking bituminous coal. The prebaked anode product prepared according to the application has better homogeneity and better product performance, the raw material source of the prebaked anode is expanded, and the dependence of the prebaked anode raw material on petroleum coke and coal pitch is reduced.

The invention belongs to the technical field of high-performance fibers, and particularly relates to an ultra-high molecular weight polyethylene submerged fishing line which is prepared by swelling a skin structure and a core structure and then spinning, the skin structure is an ultra-high molecular weight polyethylene skin layer which contains a hydrophilic polymer aid and accounts for 5-40% of the mass of the skin structure, and the core structure is an ultra-high molecular weight polyethylene core layer which accounts for 5-40% of the mass of the core structure. The core structure is an ultra-high molecular weight polyethylene core layer which contains nano inorganic powder and accounts for 60-95% of the mass of the core structure. Through the unique design of the skin part structure and the core part structure, the fishing line can naturally sink in water, the sinking performance of the ultra-high molecular weight polyethylene fishing line is achieved, the fishing experience feeling is greatly improved, the problems that in the prior art, a sinking PE fishing line is large in production difficulty and poor in effect are solved, and the production cost is reduced. The comprehensive performance and the user experience of the fishing line are remarkably improved, and the fishing line has a wide market application prospect.

The invention discloses a hard carbon material, a preparation method thereof, a pole piece and application. The preparation method of the hard carbon material comprises the following steps: carbonizing oxidized asphalt and molecular sieves, and removing the molecular sieves to obtain the hard carbon material, the mass ratio of the oxidized asphalt to the molecular sieve is 1: (1-20). The hard carbon material prepared by the preparation method disclosed by the invention has relatively high true density and relatively high open pore volume ratio. The battery prepared from the hard carbon material has better first coulombic efficiency. The preparation method of the hard carbon material is simple to operate and beneficial to industrial production.

The application discloses a preparation process of high-processing-performance and high-capacity negative electrode material precursor, belongs to the field of production of needle coke and preparation and processing of negative electrode material precursor, and comprises a preparation stage of heavy mixed oil, a green coke reaction stage and a steam blowing and coking stage, and is characterized in that: refined product oil obtained in an oil slurry pretreatment stage is mixed with a promoter and a mixing agent according to a certain proportion to obtain the heavy mixed oil, and the needle coke is obtained through the green coke reaction stage and the steam blowing and coking stage by using the heavy mixed oil; the application has the beneficial effects that: the mixing agent and the promoter are creatively added, the fibrous and domain structure of the needle coke is improved, the true density of the needle coke is improved, the capacity and the graphitization degree of the needle coke after crushing and graphitization are improved, the operation of variable temperature and variable pressure is adopted in the green coke stage, the better fusion and coalescence of the intermediate phase are ensured, the true density is improved, and a certain amount of volatile components are reserved, the good processing performance is ensured, the yield in the crushing stage is improved, and the processing cost of the negative electrode enterprise is reduced.

This invention discloses a method for preparing high-density, large-particle-size spherical alumina powder, belonging to the field of inorganic non-metallic material preparation technology. The method uses industrial aluminum hydroxide or industrial alumina containing a transition phase as raw material. It involves introducing 1-10% α-alumina seed crystals and 1.0-3.0% composite mineralizer (containing boron and fluorine sources) by mass of the raw materials. After mechanical mixing, the mixture is calcined in air at 1350-1550℃ for 2-8 hours. Finally, the mixture is cooled, dispersed, and sieved to obtain the final product. This invention, through the synergistic effect of seed crystals and composite mineralizer, simultaneously achieves α-phase transformation, densification, grain growth, and morphology control of alumina powder under mild calcination conditions. It successfully prepares alumina powder with an α-phase content ≥96%, true density >3.96 g / cm³, median particle size D50 ≥50 μm, and a regular spherical morphology. This method is simple, low-cost, and the product is suitable for high-filling thermally conductive fillers, showing great promise for industrial application.

The present invention relates to a carbon-nitrogen doped cerium dioxide / tourmaline ozone oxidation catalyst and its preparation method and application. The catalyst raw materials include iron tourmaline powder, lees and cerium nitrate, wherein the mass percentage of the iron tourmaline powder is 50% to 80%. The catalyst has good catalytic activity, stability and recovery performance through carbon-nitrogen doping and the interaction between cerium dioxide and tourmaline, and is conducive to wide promotion in the field of water treatment.

The invention provides a negative electrode material and a battery, the negative electrode material comprises graphite, holes are formed in the surface and / or the interior of the graphite, the pore volume of the negative electrode material is V cm < 3 > / kg, the true density is D g / cm < 3 >, the specific surface area is S m < 2 > / g, the graphitization degree is G%, VS / D is larger than or equal to 0.7 and smaller than or equal to 3.95, and G is larger than or equal to 89 and smaller than or equal to 93. According to the negative electrode material and the battery provided by the invention, the rate capability and the cycle performance of the graphite negative electrode material under high-rate current can be improved.