6results about How to "Control particle size" patented technology

The application discloses a preparation method of an iron-based catalyst, the iron-based catalyst and application of the iron-based catalyst. The preparation method mainly comprises three steps: firstly, a mixed solution of an iron-based precursor and an organic template agent with uniform distribution is prepared by means of stable temperature and autogenous pressure in a solvothermal process; subsequently, a weak alkaline precipitant without alkali metal is added into the mixed solution under heating to prepare an iron-based precipitate; finally, a honeycomb-shaped iron-based catalyst for ortho-para hydrogen conversion is prepared through steps of cleaning, drying, calcining, granulating, re-cleaning and activation. By adding the organic template agent, the pore structure of the catalyst is effectively improved without affecting the crystal type of the catalyst, and the performance of the catalyst is improved; and the weak alkaline precipitant without alkali metal is adopted, so that the controllability of the preparation process of the catalyst is enhanced, the influence of impurities such as alkali metal ions on the performance of the catalyst is effectively avoided, and the method has a simple process and high practical potential.

The utility model belongs to the technical field of powder feeders, and particularly relates to a laser cladding powder feeder with a screening function, which comprises a support frame and a machine body, the machine body is arranged at the top of the support frame, a button is arranged on the front side surface of the support frame, and a screening device is arranged in the machine body; the screening device comprises a fixing plate, and the fixing plate is fixedly connected to the inner wall of the machine body. Through the arrangement of the steering device, the stop block is in contact with the stress rod, the stress rod is forced to be stressed to drive the screening plate to slide upwards on the inner wall of the rectangular groove, and when the stop block is stressed to rotate continuously, the stress rod is forced to lose force so as to drive the screening plate to reset through the elastic force of the spring, so that the screening effect is achieved; and the uniformity of the material powder is guaranteed, and the problems that the screening effect cannot be achieved and the particle size of the material powder cannot be controlled due to the fact that the stress rod cannot drive the screening plate to move are solved.

This invention discloses a method for preparing a perfluorosulfonic acid resin alcohol aqueous dispersion. The method involves: placing solid perfluorosulfonic acid resin in a high-pressure reactor, using water as a solvent, and dissolving it under high temperature and pressure for 4–20 hours under inert gas protection to obtain a perfluorosulfonic acid resin aqueous dispersion; placing the perfluorosulfonic acid resin aqueous dispersion in a glass reactor, mixing it with an organic solvent, and reacting it under certain temperature conditions for 2–8 hours to obtain a perfluorosulfonic acid resin alcohol aqueous dispersion with uniformly dispersed molecular chains after secondary dispersion. Using this invention, the process is simple, time-efficient, and suitable for industrialization. The prepared perfluorosulfonic acid resin alcohol aqueous dispersion has a moderate particle size and uniformly dispersed molecular chains, making it suitable for proton exchange membrane coating processes, and thus enabling the preparation of composite proton exchange membranes with excellent mechanical and electrochemical properties.

The invention discloses a method and a device for synthesizing lithium sulfide with a controllable particle size. The method comprises the following steps: S1, dissolving lithium sulfide; performing evaporation concentration and low-temperature drying to obtain a lithium hydrosulfide powder raw material; s2, introducing high-purity hydrogen sulfide gas into a crushing and mixing chamber, and further crushing and fully mixing under strong impact of high-speed jet flow; s3, performing vulcanization reaction through the fluidized bed reaction chamber to obtain high-purity lithium sulfide particles; and S4, after synthesis is completed, transferring into a glove box. Compared with the prior art, the method disclosed by the invention has the advantages that the ethanol is adopted as a solvent, the uniformity of a lithium sulfide initial blank shell can be ensured to the greatest extent through a recrystallization method, and the high-quality lithium sulfide with controllable particle size can be obtained more quickly by accurately controlling the pressure of high-speed jet flow and regulating and controlling the particle size of a precursor material through the crushing and mixing chamber; the purity is higher, the particle size distribution is more uniform, the operation process is simple, convenient and feasible, and the method is suitable for large-scale industrial production.

The invention belongs to the technical field of functional membrane materials, and particularly relates to a synthesis process of a nano environment-friendly functional membrane material. By adopting a composite emulsifier system with a specific ratio, the particle size and distribution in the emulsion polymerization process are effectively controlled by the generated synergistic stabilization effect, the polymer emulsion with uniform particle size and high stability is obtained, and nano silicon dioxide is uniformly dispersed in a polymer matrix after being subjected to dual modification by dopamine and a silane coupling agent, so that the nano silicon dioxide can be dispersed in the polymer matrix. The mechanical property and the thermal stability of the material are effectively enhanced. Through low-temperature initiation and staged heating crosslinking, a polymer network is formed more uniformly and compactly, so that the water resistance and barrier property of the material are remarkably improved. According to the invention, recovery of organic matters in wastewater and cyclic utilization of water are realized through a ceramic membrane separation and reverse osmosis combined process. According to the overall scheme, the comprehensive performance of the membrane material is improved, meanwhile, process feasibility and environment friendliness are considered, and the method is suitable for large-scale production of the high-performance environment-friendly membrane material.

The application discloses a modification method for realizing the conductivity of basalt fiber. The method forms a conductive polymer on the surface of the basalt fiber through an in-situ polymerization method, so that the basalt fiber is endowed with conductivity. The method can control the particle size of the conductive polymer, the coating thickness and the conductivity of the basalt fiber by adjusting experimental parameters such as the types and concentrations of monomers, oxidants and dopants and the polymerization reaction time. The method is simple and efficient in manufacturing process, and is strong in controllability of structure and performance. The modified basalt fiber has good conductivity, and the resistivity of the basalt fiber is adjustable in the range of 1~10 ‑3 Ω·cm, which widens the application of the basalt fiber in the fields of electromagnetic shielding and electrostatic protection. Moreover, the method does not damage the structure of the fiber itself while realizing the conductivity of the basalt fiber, and improves the mechanical performance of the basalt fiber to a certain extent.