5results about How to "High active site density" patented technology

This invention relates to the field of metal oxide technology, specifically to a highly dispersed nano-gadolinium oxide and its preparation method. The preparation method includes: activating surface sites through weak acid etching, pulsed ultrasonic depolymerization, and hydrothermal re-hydroxylation; adsorption using a polycarboxylic acid chelating agent; introducing hydrophobic chains and tertiary amine groups through sequential amidation; forming a strongly hydrated outer layer through beet alkalization; and finally, ultrafiltration desalting and concentration. The nano-gadolinium oxide dispersion obtained by this method has advantages such as narrow particle size distribution, low viscosity, good storage stability, and strong electrolyte resistance, making it suitable for high-end applications such as polishing slurries and coating precursors.

The present application provides a colloid bitumen dispersant and its preparation method and application, and belongs to the technical field of oil field exploitation. It comprises the following components: dispersant mother liquor containing hyperbranched complex 60-100 parts, solvent 20-30 parts, sodium dodecyl benzene sulfonate 2-5 parts, alpha-alkyl sodium sulfonate 1-3 parts, ethylenediaminetetraacetic acid disodium 2-5 parts, low carbon alcohol 5-15 parts, antioxidant 0.5-2 parts. Through the design of complex structure, the construction of green solvent system and the innovative synthesis process, the present application realizes the synchronous collapse of colloid hydrogen bond network and asphaltene pi-pi accumulation, significantly reduces the dispersant dosage and preparation energy consumption, and has broad application prospect.

The application discloses an organic-alloy composite graphite felt and a preparation method and application thereof, and comprises the following steps: preparing pretreated graphite felt; preparing precursor graphite felt by reacting triphenylphosphine-copper hydride hexamer and silver trifluoromethanesulfonate; reacting the precursor graphite felt with ammonia water and an organic reducing agent solution, and performing multi-step freeze drying to obtain the organic-alloy composite graphite felt. By constructing a unique organic-alloy composite structure on the graphite felt substrate, the active site density of the electrode surface is effectively increased, and the activation energy of the vanadium ion redox reaction is greatly reduced. Through complexation reaction, the phosphorus-containing compound and the carboxylic acid-containing compound are combined on the graphite felt and V 2+ The electrostatic attraction forms an ion cluster body with vanadium ions as the core, hinders the V 2+ agglomeration to form a precipitate, inhibits the generation selectivity of the precipitate, improves the thermal stability of the electrolyte, and further improves the battery efficiency.

The application discloses an organic-alloy composite graphite felt and a preparation method and application thereof, and comprises the following steps: preparing pretreated graphite felt; preparing precursor graphite felt by reacting triphenylphosphine-copper hydride hexamer and silver trifluoromethanesulfonate; reacting the precursor graphite felt with ammonia water and an organic reducing agent solution, and performing multi-step freeze drying to obtain the organic-alloy composite graphite felt. By constructing a unique organic-alloy composite structure on the graphite felt substrate, the active site density of the electrode surface is effectively increased, and the activation energy of the vanadium ion redox reaction is greatly reduced. Through complexation reaction, the phosphorus-containing compound and the carboxylic acid-containing compound are combined on the graphite felt and V 2+ The electrostatic attraction forms an ion cluster body with vanadium ions as the core, hinders the V 2+ agglomeration to form a precipitate, inhibits the generation selectivity of the precipitate, improves the thermal stability of the electrolyte, and further improves the battery efficiency.

The invention discloses a preparation method of silver-plated copper powder based on high-activity replacement, and belongs to the technical field of metal surface treatment. The copper powder is subjected to alkali washing, acid washing and water washing and then subjected to ultrasonic treatment for 15-25 min at the temperature of 60-70 DEG C with a 35-45 vol% ethanol water solution. The surface activated copper powder is dispersed in a solution containing 10-30 g / L of a complexing main agent and 8-15 g / L of a complexing auxiliary agent, EDTA disodium is preferably selected as the complexing main agent, and potassium sodium tartrate is preferably selected as the complexing auxiliary agent. A silver-ammonia solution with the Ag < + > concentration being 8-12 g / L and the ammonia water concentration being 2.5-4.0 mol / L is dropwise added into a reaction system at the temperature of 35-45 DEG C at the speed of 0.2-1.0 mL / min; and after the reaction is finished, centrifugally washing the silver-plated copper powder, and drying in vacuum. According to the method, ethanol mixed liquid is used for heating ultrasonic treatment of copper powder, and active site density is improved. A double-complexing slow-release system is used for controlling the reaction rate, a complexing main agent is used for preventing particle aggregation caused by rapid reduction, and a complexing auxiliary agent is used for cooperatively regulating and controlling the Ag < + > release rate, so that a silver layer uniformly grows. And dropwise adding a silver-ammonia solution in a low-temperature gradient manner to realize gradual reduction of Ag < + >. The silver content of the prepared silver-plated copper powder is 20-25%, and the silver layer coverage rate is larger than or equal to 96%.