18 results about "Displacement reactions" patented technology

The application discloses an intermediate processing liquid for an electroless nickel immersion gold (ENIG) production line and a chemical gold preparation method. The intermediate processing liquid is applied between the electroless nickel plating and immersion gold processes, and comprises (a) a pH buffer and a metal ion complexing agent: a total concentration of 50-150 g / L; (b) an adsorptive corrosion inhibitor: a concentration of 0.5-5.0 g / L; (c) a low-foam non-ionic surfactant: a concentration of 0.01-10 g / L; (d) an auxiliary antioxidant: a concentration of 0.5-30 g / L; (e) a dissolving agent: a concentration of 1-50 ml / L; (f) a pH regulator: an appropriate amount, which is added to maintain the pH value of the intermediate processing liquid at 4.0-6.5; and (g) deionized water: a balance, so that the concentrations of the above components reach the set target values; and the intermediate processing liquid has a design use temperature of 20-45 DEG C. The intermediate processing liquid removes residual nickel ions on the board surface and in micropores through strong complex cleaning, and blocks the pollution to the subsequent gold tank; meanwhile, the preferential adsorption of the corrosion inhibitor molecules at the nickel layer grain boundaries forms a controllable molecular-level protective film, effectively adjusts the immersion gold replacement reaction kinetics, and prevents the occurrence of intergranular corrosion (black plate).

The application discloses a continuous iron dissolving method for preparing iron phosphate, and comprises the following steps: S1, acid solution is added into a dynamic tubular reactor for pre-washing, and the flow of the acid solution is calibrated, and iron powder is added into the dynamic tubular reactor according to a reducing parameter; S2, a displacement reaction occurs in the dynamic tubular reactor, and the dynamic tubular reactor is in a closed and slightly negative pressure environment; acid mist and by-product hydrogen overflowing from the dynamic tubular reactor are pumped into a gas-liquid separator, and then the hydrogen is pumped into a hydrogen storage tank; S3, the iron phosphate solution obtained through the reaction of the dynamic tubular reactor is filtered through a bag filter through the gas-liquid separator, and then the iron phosphate solution is sampled and analyzed to obtain a clear iron dissolving solution. The application can accurately control the addition amount of raw materials, so that the iron powder is fully reacted in the reactor without residual iron powder, and the continuous iron dissolving process is realized. The safety problem caused by the high hydrogen concentration in the environment due to hydrogen production in the iron dissolving process is effectively solved.

This invention discloses a method for preparing high-purity terbium-iron alloy, utilizing ferric fluoride as a chemical decalcification agent in the refining stage. Compared with existing technologies that rely solely on high-temperature volatilization and physical adsorption for calcium removal, this method provides a clear chemical driving force, converting calcium dissolved in the alloy melt into an insoluble calcium fluoride slag phase through a displacement reaction, thereby achieving efficient calcium removal. This invention can reduce the calcium content in terbium-iron alloy from 0.011-0.015% in traditional processes to 0.002-0.004%, a reduction of 70-85%. This method requires no special equipment; only the addition of ferric fluoride in the refining stage is needed, resulting in low process modification costs and good industrial applicability.

The invention discloses a transition metal sulfide single crystal with a macro-size asymmetric structure as well as a preparation method and application thereof. The preparation method comprises the following steps: providing a macro-size single-layer transition metal sulfide as a precursor; placing the substrate bearing the precursor in a reaction chamber in a non-horizontal orientation manner, so that a non-zero included angle is formed between the surface of the precursor and the dominant transmission direction of reactant flow in the reaction chamber; hydrogen plasma and a heterogeneous chalcogenide element source are introduced into the reaction chamber at the same time, an atomic layer replacement reaction is carried out under the room temperature condition, chalcogenide atoms on the top layer of the precursor are replaced by heterogeneous chalcogenide atoms, and after the replacement reaction is completely carried out, the transition metal sulfide single-layer material of the Janus structure is obtained. According to the method, the preparation of the high-quality Janus TMDC single crystal with the transverse size reaching the millimeter scale is realized, the prepared Janus single crystal has high spatial uniformity on the millimeter scale, and the process is simple, controllable and large-scale.

This invention provides an iridium cobalt oxide electrocatalyst, its preparation method, and its application. First, metallic Co is electrodeposited onto a Ti fiber mat, and then it is placed in an Ir... 3+ In solution, an electrochemical displacement reaction driven by the potential difference between two metals successfully deposited the noble metal Ir onto the surface of metallic Co. Finally, calcination in air yielded an iridium-cobalt oxide electrocatalyst. This invention utilizes an electrochemical displacement reaction to synthesize an iridium-cobalt oxide electrocatalyst simply and conveniently, by altering the noble metal Ir. 3+ By controlling the coordination environment of noble metal active sites through concentration and reaction time, a highly efficient and stable iridium-cobalt oxide was successfully constructed on the surface as an oxygen-generating active center. This solves the problems of high noble metal loading, low activity, and low stability in existing acidic oxygen-generating electrocatalysts, providing a simple, rapid, low-cost, and efficient solution for industrial-scale production.

The invention belongs to the technical field of electrocatalytic materials, and discloses an electrocatalyst for selectively preparing hydrogen peroxide by controlling an oxygen reduction reaction path and application. The electrocatalyst is a composite material in which a Fe3O4 dispersion liquid, an amino-containing monomer, an aldehyde-containing monomer and a zinc salt are subjected to a Schiff base reaction in the presence of a catalyst to obtain a product, and the product and a magnetic metal salt are subjected to a replacement reaction to prepare a metal monatomic covalent organic framework which coats the surface of a magnetic matrix Fe3O4 in a shell form; the Fe3O4 dispersion liquid is prepared by mixing Fe3O4 nanoparticles and a dispersing aid, and the size of the Fe3O4 nanoparticles is smaller than or equal to 100 nm. The electrocatalyst according to the present invention is used to control an oxygen reduction reaction path (2 electron path), thereby achieving high-selectivity production of hydrogen peroxide.

The purpose of this invention is to provide a carbon framework supported and embedded Ni3ZnC 0.7 This paper describes the preparation method and application of NiPt1 single-atom alloy catalysts, belonging to the field of functional materials technology. Using a core-shell structure ZIF-8@Ni-MOF as a precursor, porous carbon-supported Ni3ZnC catalysts are prepared by controlling the pyrolysis temperature, time, and Zn / Ni molar ratio. 0.7 Ni particles; Pt single atoms are anchored in situ using current displacement to form a supported single-atom alloy catalyst. Because Pt 4+ with Ni 0 A current displacement reaction occurs, causing Ni nanoparticles to be etched into small nanoclusters, while simultaneously anchoring Pt single atoms to their surface, thus producing a Ni3ZnC coating. 0.7 The outer layer is a NiPt1 single-atom alloy. Ni3ZnC 0.7 The tunable electronic structure of Ni can alleviate OH blockage and lower the water dissociation energy barrier, providing a new pathway for the development of highly efficient alkaline HER catalysts.

The application provides a preparation method of 1,4-bis(chlorodifluoromethyl)benzene, which comprises the following steps: (1) performing a chlorination reaction on terephthaldehyde, a chlorination reagent and a catalyst to obtain 1,4-bis(dichloromethyl)benzene; (2) performing a fluorine-chlorine displacement reaction on the 1,4-bis(dichloromethyl)benzene obtained in the step (1) and a fluorination reagent to obtain 1,4-bis(difluoromethyl)benzene; (3) performing a reaction on the 1,4-bis(difluoromethyl)benzene obtained in the step (2) and an electrophilic chlorination reagent to obtain the 1,4-bis(chlorodifluoromethyl)benzene. The preparation method has the advantages of simple operation, low toxicity of raw materials, high yield and high purity, solves the problems of difficult scale production, low yield and high toxicity and high cost of raw materials in the prior art, and has great industrial value.

Disclosed in the present invention is a preparation method, comprising the following steps: S1. preparing a salt solution of metal A ions and a solution containing elemental metal B particles, the reducing ability of metal B being greater than the reducing ability of metal A; and S2. simultaneously introducing the salt solution of metal A ions and the solution containing elemental metal B particles into a reaction vessel, while synchronously applying a negative pressure to the reaction vessel, so that the salt solution of metal A ions and the solution containing elemental metal B particles both form a turbulent flow state within the reaction vessel, and performing a displacement reaction, such that surface atoms of the elemental metal B particles are replaced by elemental nanoscale metal A, thereby forming a multiphase composite core-shell material, so as to obtain a metallization slurry for a package substrate. The preparation method for a metallization slurry for a package substrate proposed by the present invention is beneficial for simplifying a preparation process, improving production efficiency, and facilitating industrial-scale production, while ensuring the uniformity of the obtained multiphase composite core-shell material, thereby ensuring the stability of the performance of the metallization slurry.

The invention relates to the technical field of preparation of patterned flexible conductive films, in particular to a roll-to-roll preparation method and device of a patterned flexible conductive film. A flexible base material passes through the unwinding module, is activated / cleaned and then enters the light projection patterning unit to obtain a metallized pattern, then chemical plating or replacement reaction is carried out through the metal deposition module to further enhance the conductivity, and finally a prepared sample is collected by the winding module. According to the invention, the roll-to-roll process, the digital light processing technology and the copper plating or replacement reaction process are combined for the first time, and efficient and continuous preparation of the patterned flexible conductive film is realized.

The invention belongs to the technical field of preparation of anhydrous aluminum trichloride, and particularly relates to a method and device for preparing anhydrous aluminum trichloride based on a low-temperature indirect chlorination method, and the method comprises the following steps: introducing chlorine gas into a molten medium material Me at 185-650 DEG C, so that the molten medium material Me and chlorine gas are subjected to chlorination reaction to generate chloride, then, AlCl3 is generated through a replacement reaction between the solid Al and chloride, aluminum chloride generated through the reaction is sublimated and enters a trap, and an anhydrous aluminum trichloride finished product is obtained after trapping; wherein the melting point of the medium material Me is 185-650 DEG C, the medium material Me can react with chlorine to generate chloride, and the chloride of the medium material Me can be subjected to replacement reaction with aluminum to generate metal or alloy of AlCl3; according to the method and the device for preparing the anhydrous aluminum trichloride based on the low-temperature indirect chlorination process, the aim of preparing the high-purity anhydrous aluminum trichloride with low cost, low energy consumption, low investment and high yield can be achieved.

The invention provides micron-sized spherical silver-coated copper powder and a preparation method thereof, and belongs to the technical field of metal powder.The preparation method comprises the following steps that copper powder is pretreated, and pretreated copper powder is obtained; under the condition of constant temperature, a part of the silver complexing solution is dropwise added into the copper powder mixed solution to obtain a reaction solution, and then the remaining silver complexing solution and the reduction solution are dropwise added into the reaction solution at the same time; and after the reaction is finished, carrying out solid-liquid separation, washing and drying to obtain the micron-sized spherical silver-coated copper powder. According to the invention, a replacement and chemical reduction method silver plating process is realized through a continuous feeding method. The method comprises the following steps: adding a small amount of silver complexing solution to perform replacement reaction with copper powder to generate silver nanoparticles on the surface of the copper powder; and then the reducing solution and the silver complexing solution are added into the copper powder at the same time, generated silver particles can be evenly deposited along the silver nanoparticles on the surface of the copper powder under the action of the reducing agent, and the utilization rate of silver ions is high.

This invention belongs to the field of oil extraction and relates to a method for characterizing the breakthrough point of bio-nano-based unblocking and injection enhancement. The method includes: measuring the porosity and permeability of the core sample; injecting a bio-nano-based unblocking agent using KCl or NH4Cl solution for displacement, and analyzing the breakthrough point of the bio-nano-based unblocking agent; flushing the pipeline with simulated formation water, shutting off the displacement device, injecting the bio-nano-based injection enhancement agent, and measuring the porosity and permeability of the core sample again; dividing the unblocking process into a linear flow model into contaminated and uncontaminated zones, determining the contaminated skin coefficient based on Darcy's formula and the definition of the skin factor, and determining the fluid viscosity in the contaminated zone and the fluid viscosity in the uncontaminated zone at any given time; deriving the relationship between pressure difference and time during the core displacement reaction process based on the fitting relationship between pressure difference and the rising and falling phases of the injected PV number, and the relationship between the unblocking agent propulsion time and the injected PV number; and determining the relationship between fluid viscosity and the unblocking agent injection time based on the relationship between pressure difference and time during the core displacement reaction process.

This invention provides an apparatus for recovering copper from waste ionic liquids, comprising: a displacement reactor and a sedimentation tank. The displacement reactor includes, from bottom to top, a water and gas distribution zone, a displacement reaction zone, a three-phase separation zone, and an effluent zone, all connected sequentially. The effluent zone surrounds the upper part of the three-phase separation zone. The water and gas distribution zone is provided with a reactor inlet and a reactor gas inlet. The displacement reaction zone includes, from bottom to top, a support layer and an aluminum particle layer. The three-phase separation zone is provided with a three-phase separator, the aqueous phase outlet of which is connected to the effluent zone. The effluent zone is connected to the sedimentation tank, and the sedimentation tank is provided with a sedimentation tank outlet, a circulating water outlet, and a sedimentation outlet at its upper, middle, and bottom parts, respectively. This invention also provides a method for recovering copper from waste ionic liquids. This apparatus is space-saving, has a high copper displacement recovery rate, strong shock resistance, and can effectively recover copper resources and reduce wastewater treatment costs, showing broad application prospects.

The application provides a gold nanoflower SERS substrate and a preparation method and application thereof, the preparation method removes the surface oxide film of an aluminum foil by using an etching solution, and realizes in-situ growth of the gold nanoflower on the surface of the aluminum foil by combining with a spontaneous displacement reaction of chloroauric acid. The preparation process is simple to operate, does not need an external power supply, raw materials are easy to obtain, and the cost is low; in addition, the substrate can be prepared in a large area, and the problems of a traditional SERS substrate, such as complicated process, high cost and difficulty in large-scale production, are effectively solved. The prepared substrate has a multi-stage rough microstructure, a high-density and uniformly-distributed SERS hot spot is formed on the surface, and the Raman signal enhancement effect is excellent. The substrate does not need sample labeling and substrate surface modification, and can quickly complete Raman spectrum detection of pseudomonas aeruginosa; in addition, the five types of carbapenemases can be accurately identified, and the detection process is efficient, and the result is stable and reliable.

The application provides a waste battery recycling method and device. The method uses a low-melting-point molten salt with reducing property as a reactant to separate elements such as Li, Co, Ni and Mn in the waste battery from oxygen elements, to generate a chlorosalt which is easier for subsequent displacement reaction, and through the displacement reaction, the elements such as Li, Co, Ni and Mn in the waste battery can be extracted step by step, and the recycling process is simplified. The waste battery recycling method has the advantages of low cost, high recovery yield and low requirement for recycling equipment.

The present disclosure describes in detail a polymerase-free, isothermal method for detecting nucleotide sequences. The method uses a target-specific hairpin oligonucleotide that also specifically interacts with a probe labeled with a fluorescent dye and a quenching group, amplifying detection of the target polynucleotide through repeated cycles of endonuclease-mediated probe cleavage to drive dissociation of the fluorophore-labeled probe fragment from the hairpin-probe complex, thereby separating the fluorescent label from the quencher.

The utility model discloses a device for replacing silver chloride with iron powder, which belongs to the technical field of gold mine, and comprises a left reaction unit and a right reaction unit, the left reaction unit comprises a left reaction kettle and a left filter, the left reaction kettle is connected with the left filter through a pipeline I, the pipeline I is provided with a left discharge valve, and the right filter is provided with a right discharge valve. A left water adding hole, a hole I and a left operation hole are formed in the top of the left reaction kettle, a stirring device is arranged in the left reaction kettle, and the left filter is connected with a suction filter; the right reaction unit and the left reaction unit have the same structure; the left reaction unit further comprises a first pump used for transferring a solution at the bottom of the left filter into the right reaction unit. The left reaction unit and the right reaction unit which are the same in structure are designed to support continuous operation, after the left reaction unit completes iron powder replacement reaction, filtrate is directly transferred to the right reaction unit to be neutralized, and silver powder loss caused by material transfer is reduced.