175results about How to "Improve mass transfer effect" patented technology

The invention discloses a p-methyl benzyl chloride production process and a production system thereof, p-xylene side chains and chlorine are subjected to a gas phase substitution reaction under micro negative pressure and visible light catalysis to generate crude methyl benzyl chloride and hydrogen chloride, and 99.0% methyl benzyl chloride, a small amount of benzyl dichloride and 31% hydrochloric acid are respectively generated through rectification and absorption; the device consists of four working sections of chlorination, rectification, hydrochloric acid absorption and distillation. According to the method, the defects in the prior art are overcome, on one hand, chlorine is introduced, and an aromatic ring chlorination reaction is carried out under visible light catalysis; on one hand, a supported catalyst filler is arranged at the bottom of a chlorination tower, and a zeolite molecular sieve modified by long-chain alkylsilane and supported by metal salt is used as a catalyst to catalyze chloromethylation reaction, on the other hand, the hydrophobicity of the modified catalyst is obviously enhanced, and meanwhile, the density of acidic sites is not reduced; the contact opportunity of the catalyst and a reaction substrate is greatly increased, and the catalytic efficiency of the catalyst is improved.

The invention discloses an internal circulation rotating impinging stream electro-catalysis device and method for treating organic wastewater, and belongs to the technical field of sewage treatment equipment. The upper part of an inner cavity of an electrochemical reactor of the device is an electrochemical reaction area, and the lower part is a rotational flow generation area; the electrochemical reaction area comprises an outer ring anode, an annular net-shaped cathode, an inner ring anode and a central fixing shaft which are sequentially and coaxially sleeved from outside to inside, and the rotational flow generation area comprises an inner spiral generator and an outer spiral generator which are arranged on a spiral central shaft in a sleeving manner. The impinging stream technology and the electro-catalysis technology are combined, internal circulation impinging stream efficient treatment on organic wastewater is achieved through the rotational flow generation area, the device has the advantages of being high in treatment efficiency, small in occupied space, low in operation energy consumption and the like, the problem that bubbles adhere to the surface of an electrode can be solved, strong turbulent flow is formed through impinging, reaction dead zones are reduced, and the service life of the device is prolonged. Mass transfer in the electrochemical degradation device is enhanced, and the purposes of automatic operation and efficient degradation are achieved.

The invention provides an amine low-water-content absorbent for capturing carbon dioxide and application of the amine low-water-content absorbent. The amine low-water absorbent comprises, by mass, 20%-50% of an absorbent main agent, 35%-70% of an auxiliary solvent and 2%-20% of water, and the range of a solvent effect factor delta of the amine low-water absorbent is 0.28-0.32. According to the method, the composition of the water-less absorbent is screened and optimized through a solvent effect factor formula, the amine water-less absorbent which is easy to desorb, low in regeneration energy consumption and low in viscosity characteristic is obtained, and wide application of the amine water-less absorbent in a carbon capture technology is promoted.

The invention discloses printing and dyeing sewage treatment equipment with a filter screen cleaning function, which comprises a sedimentation tank for treating sewage, a partition plate is fixed in the sedimentation tank, the partition plate divides the sedimentation tank into a physical treatment cavity and a biological treatment cavity, and a through hole for sewage circulation is formed in the partition plate; a rotating shaft capable of rotating transversely penetrates through the partition plate, and a motor for driving the rotating shaft to rotate is mounted at the upper end of the sedimentation tank; the rotating shaft is divided into two parts by a partition plate, and a collector for filtering sewage and a mixer for mixing the sewage are respectively arranged on the two parts of the rotating shaft. According to the invention, suspended matters in sewage can be blocked by the filter strip, the rotating filter strip changes the matching position with the through hole, the suspended matters are easily separated from the filter strip, the outer side fan plate pushes the sewage to move towards the rotating shaft, the filter strip adheres to the suspended matters and moves into the annular hole, the suspended matters are remained in the receiving box, and the number of times of cleaning the suspended matters is reduced.

The invention relates to a preparation method of H12MDA with low trans-trans isomer content and a catalyst used in the preparation method. The catalyst is a supported catalyst and comprises a silicon-aluminum amorphous carrier and an active component, the silicon-aluminum amorphous carrier has a micropore, mesopore and macropore structure and is prepared by carrying out hydrothermal reaction on raw materials comprising an aluminum source and a silicon source in the presence of a template agent, and the template agent is selected from 4, 4-diaminodiphenyl-methane and 2, 4-diaminodiphenyl-methane or 2, 4-diaminodiphenyl-methane or 2, 4-diaminodiphenyl-methane or 2, 4-diaminodiphenyl-methane or 2, 4-diaminodiphenyl-methane or 2, 4-diaminodiphenyl-methane or 2, 4-diaminodiphenyl-methane. The catalyst is one or a combination of two of 1, 4-diaminodiphenylmethane. The catalyst is long in service life and excellent in stability, the yield of an H12MDA target product can be increased, the content of trans-isomers in the product is reduced, and the preparation process is also simple. The invention also provides a method for preparing H12MDA through MDA catalytic hydrogenation, and the method can improve the yield of the H12MDA product and obviously reduce the content of trans-isomers in the product.

The invention belongs to the technical field of ammonia synthesis and electro-catalysis, and particularly relates to a preparation method and application of high-entropy alloy aerogel for electro-catalysis. The preparation method comprises the following steps: mixing an inorganic metal salt in a solvent to obtain a precursor solution, quickly adding a reducing agent, standing, and washing and drying the obtained product to obtain the high-entropy alloy aerogel catalyst, the inorganic salt is selected from five or more of copper salt, cobalt salt, iron salt, nickel salt, palladium salt, gold salt, ruthenium salt, platinum salt and silver salt. The three-dimensional continuous porous reticular high-entropy alloy aerogel is obtained through one-step reduction of the inorganic metal salt and standing assembly, the high-entropy alloy aerogel prepared through the method is high in reduction assembly speed, phase separation of multi-component alloy can be effectively inhibited, an amorphous alloy structure is obtained, and therefore when the high-entropy alloy aerogel is applied to ammonia production through electro-catalysis nitrate reduction, the high-entropy alloy aerogel can be used for preparing the high-entropy alloy aerogel. And excellent electrochemical activity and stability can be presented in an ultra-low overpotential range of-0.2 to + 0.2 V vs.RHE.

The invention relates to a nickel-based methanation catalyst taking a mesoporous molecular sieve SBA-16 as a carrier and application of the nickel-based methanation catalyst in carbon dioxide hydrogenation. The catalyst is prepared by preparing a mesoporous molecular sieve SBA-16 as a carrier, dissolving nickel salt in a solvent, adding an additive, and combining the SBA-16 carrier with nickel metal by an impregnation method. The catalyst has high activity and good stability, especially has excellent performance in a CO2 methanation reaction, can realize high CO2 conversion rate and high CH4 selectivity at a low temperature, and is suitable for reaction conditions with a temperature of 200-400 DEG C and a pressure of normal pressure to 5.0 MPa. The preparation method of the catalyst is simple, does not need precious metal, and has potential industrial application prospects.

The utility model relates to a tubular ultrasonic coagulation inclined tube sedimentation tank, which belongs to the field of sewage treatment equipment and comprises a lifting pump, an ultrasonic generation component and an inclined tube sedimentation tank. The ultrasonic generation assembly comprises a frequency-adjustable ultrasonic generator, a tubular ultrasonic coagulation reactor, an ultrasonic transducer, an ultrasonic amplitude-change pole and an ultrasonic emission head; the ultrasonic emission head is connected with the tubular ultrasonic coagulation reactor, and the frequency-adjustable ultrasonic generator is connected with the ultrasonic transducer; the ultrasonic amplitude-change pole is connected between the ultrasonic transducer and the ultrasonic emission head; an outlet of the lifting pump is communicated with a water inlet of the tubular ultrasonic coagulation reactor; a water outlet of the tubular ultrasonic coagulation reactor is communicated to the inclined tube sedimentation tank through a pipeline; the device is simple in structure, high in reaction speed, small in size, capable of being directly installed on a pipeline for use, adjustable in reaction strength and long in service life. The solid-liquid separation efficiency of the inclined tube sedimentation tank can be improved, and the effect of removing SS, TP, COD, algae, turbidity and the like is achieved.

The invention provides a preparation method of a hydrogenated cycloolefin polymer, which comprises the following steps: reacting a cycloolefin polymer with hydrogen in the presence of a hydrogenation catalyst and a hydrogenation aid to obtain the hydrogenated cycloolefin polymer, the hydrogenation auxiliary agent is selected from one or more of aliphatic dibasic acid esters, phthalate esters and benzene polyacid esters. Compared with the prior art, in the presence of the hydrogenation catalyst and the hydrogenation auxiliary agent, the cycloolefin polymer and the hydrogen are subjected to hydrogenation reaction, and an induced dipole is induced in the adjacent cycloolefin polymer through the hydrogenation auxiliary agent molecule with an inherent dipole; the molecular attraction between the induced dipole and the inherent dipole destroys the entanglement of the original molecular chain, and the friction force between the cycloolefin polymer molecules is reduced, so that the viscosity between the polymers is reduced, and the mass transfer effect of the reaction is improved; meanwhile, intramolecular electron conjugation can be inhibited, double bonds in molecules in the hydrogenation process can be damaged more easily, the hydrogenation efficiency is improved, and then the production efficiency is improved.

The present invention relates to the field of distributed mild ammonia synthesis technology, and in particular to a plasma-assisted ammonia synthesis method based on Ni-Co bimetallic MOF. The method uses the Ni-Co bimetallic MOF material prepared by a one-step hydrothermal method as a catalyst for plasma-assisted ammonia synthesis. Relying on its enhanced gas mass transfer characteristics and the coupling effect between bimetallics, this material greatly enhances the performance of plasma-assisted ammonia synthesis: compared with the most widely used material in the field of plasma-assisted ammonia synthesis, Ni / Al2O3, the performance is enhanced by more than 30%. At the same time, in this method of using Ni-Co bimetallic MOF for plasma-assisted ammonia synthesis, the catalyst material also has good stability and cycle performance, and it can maintain the stability of structure and performance in a long period of 36h and more than 10 cycles. The excellent performance of using Ni-Co bimetallic MOF in the field of plasma-assisted ammonia synthesis makes it a huge potential for distributed ammonia synthesis process.

The invention belongs to the field of hydrogen production through water electrolysis, and particularly relates to a supported iridium oxide water electrolysis catalyst and a preparation method and application thereof. According to the preparation method disclosed by the invention, the Ti4O7 carrier with high conductivity and high specific surface area is firstly synthesized, so that the problem of poor conductivity of the traditional TiO2 powder is solved; and secondly, controllably synthesizing the porous iridium oxide catalyst with high specific surface area and high porosity on the Ti4O7 conductive carrier by controlling the use proportion of mixed molten salt through a mixed molten salt method. The supported iridium oxide catalyst synthesized by the method is high in intrinsic activity, the usage amount of noble metal is reduced, the porous structure is beneficial to charge transfer and gas transmission during water electrolysis, and the supported iridium oxide catalyst shows excellent catalytic activity and long-term stability in PEM electrolyzed water and has good commercial application potential.

The invention discloses a method for improving the texture characteristics of canned abalone. After fresh abalone is taken out, cleaned, water-controlled, shaped and salt-ground, composite protease is used to decompose collagen and elastin in the abalone meat and hydrolyze connective tissue fibers. At the same time, ultrasonic treatment is used to destroy the original muscle structure, which effectively reduces the hardness value of the abalone meat. After the treatment, the abalone meat is cleaned, water-controlled, blanched, tooth-removed and graded, and then placed in a 500V DENBA+ electrostatic wave preservation system and treated at 4°C for 1h. After that, the abalone meat is subjected to metal detection, weighing and canning, vacuum sealing, can washing, sterilization and cooling, and drying. The canned abalone treated by the above steps can improve its rubber meat texture characteristics to the greatest extent, effectively ensure the moisture of the abalone meat, and maintain its nutritional components, good flavor and taste.

The invention relates to the technical field of chemical equipment, in particular to a packed rectifying tower which comprises a tower body, a tower plate group, a liquid storage tower, a reboiler and a condenser, and a liquid inlet, a gas outlet, a gas inlet and a liquid outlet are formed in the tower body; the tower plate group comprises a first tower plate, a second tower plate... an Nth tower plate, the first tower plate, the second tower plate... the Nth tower plate are spirally inserted into the tower body, and liquid hoppers for containing liquid are arranged on the first tower plate, the second tower plate... the Nth tower plate; the liquid storage tower is used for storing liquid; the reboiler is used for heating liquid into steam; the condenser is used for cooling steam. During use, steam is upward, liquid is downward, the steam and the liquid exchange heat and mass for distillation, and the spiral tower plate group is arranged, so that the gas-liquid contact area is larger, the gas-liquid contact time is longer, the gas-liquid mass transfer effect is better, and the production efficiency is improved.

The present invention relates to a droplet-shaped fuel cell flow field structure, in which the flow field structure region is composed of a plurality of rows or columns of droplet-shaped flow field units alternately connected. Each droplet-shaped flow field unit includes a droplet-shaped support structure and flow channel structures on both sides of the support structure. The droplet-shaped flow field units are connected head to tail through a direct flow channel. The droplet-shaped fuel cell flow field structure of the present invention can increase the turbulence of the gas in the flow channel, has the advantages of good mass transfer effect and low pressure drop, and can significantly improve the performance of the fuel cell. At the same time, the droplet-shaped fuel cell flow field structure of the present invention is simple and easy to process, which is conducive to the large-scale production and application of fuel cells.

The invention discloses an anion exchange membrane electrode and a preparation method and application thereof, and belongs to the technical field of new energy material and catalytic electrode preparation, the method comprises the following steps: S1, preparing an anode catalyst slurry comprising a hydrophobic covalent organic framework material, an anode catalyst, an anion exchange ionomer and a solvent; s2, preparing a cathode catalyst slurry of which the components comprise a cathode catalyst, an anion exchange ionomer and a solvent; and S3, respectively spraying or coating the anode catalyst slurry and the cathode catalyst slurry on two side surfaces of an anion exchange membrane or a gas diffusion layer, and carrying out heat treatment to obtain the anion exchange membrane electrode. The method provided by the invention can solve the problems of large gas-liquid-ion three-phase mass transfer resistance, easy shielding of active catalytic sites by ionomers and unbalanced water management in the membrane electrode assembly in the existing AEMWE device.

The invention discloses an absorbent for carbon dioxide capture. The absorbent is a binary anhydrous phase change absorbent composed of functionalized ionic liquid triethylene tetramine-3-bromophenolate and an alcohol solvent polyethylene glycol 200, the mass fraction ratio of the functionalized ionic liquid triethylene tetramine-3-bromophenolate to the alcohol solvent polyethylene glycol 200 is (1: 9)-(5: 5), and the corresponding absorption load is 0.97-2.37 mol CO2 / kg absorbent. According to the invention, the structural adjustability of the ionic liquid is fully utilized, and the multi-amino functionalized ionic liquid with high absorption load is designed and synthesized by adjusting the types of anion and cation donors.

The invention discloses a wide-temperature-range gas diffusion layer and a preparation method and application thereof. The wide-temperature-range gas diffusion layer comprises a microporous layer and a carbon fiber substrate layer arranged on the surface of the microporous layer; the microporous layer comprises a labyrinth network structure formed by graphene, a single-walled carbon nanotube, a multi-walled carbon nanotube and a water repellent agent; the carbon fiber substrate layer comprises carbon fibers, single-walled carbon nanotubes, multi-walled carbon nanotubes and a water repellent agent. The gas diffusion layer material which is adjustable in porosity, has a certain water retention capacity and is suitable for the air-cooled PEMFC is successfully prepared by using graphene, carbon nanotubes and carbon fibers as raw materials through vacuum filtration assistance and heat treatment methods, the transmission diversity of liquid water in the gas diffusion layer can be effectively improved, and the gas diffusion layer material has a good application prospect. And the transmission distance is prolonged, the performance of the fuel cell under low humidity is improved, the mass transfer capability is improved, and the fuel cell has a relatively wide working temperature range.

The invention discloses a flow channel structure of a redox flow battery, and particularly relates to a three-dimensional staggered snake-shaped flow channel structure and an all-vanadium redox flow battery, the flow channel structure comprises two parts, and the two parts are positioned on the two sides of an electrode in the thickness direction and are respectively processed on the side surface, close to an electrode, of a bipolar plate and the side surface, close to a diaphragm, of the electrode; an inlet of the runner structure is formed in the bipolar plate side part, and an outlet is formed in the electrode side part; the flow channel structure of each part is snake-shaped, and the flow channel structures of the two parts are distributed in a staggered manner in the plane direction of the electrode. The technical problem that the convective mass transfer effect of reactive ions in the thickness direction of the electrode is improved by changing pressure gradient distribution in the electrode is solved. Under the same electrolyte flow supply and different current densities, the flow channel structure promotes the mass transfer process of reactive ions in the electrode, the brought overpotential loss is lower than that of a traditional flow channel, and the limiting current density is higher. In a charge-discharge experiment, the flow battery disclosed by the invention is smaller in overpotential and higher in charge-discharge capacity.

The invention discloses a biological coupling treatment device and method for high-salt organic wastewater, and relates to the technical field of wastewater treatment.The biological coupling treatment device comprises a pretreatment unit, a biological treatment unit, a physical and chemical treatment unit, a desalination unit and a post-treatment unit, the bio-membrane reactor comprises a biological reaction tank and an MBR membrane assembly, activated sludge is arranged in the biological reaction tank, an aeration assembly and a limiting assembly are arranged at the bottom of the MBR membrane assembly, a flow pushing assembly is arranged on the bottom side in the biological reaction tank, and the MBR membrane assembly comprises a frame. According to the invention, the aeration structure is optimized, the permeability of the MBR membrane is guaranteed, the cleaning frequency is reduced, the service life of the membrane is prolonged, in addition, the aeration structure is optimized, so that bubbles are uniformly distributed, and the oxygen content of each region is kept uniform.

The present invention discloses a high-pressure water electrolysis hydrogen production device, including an electrolytic cell stack and a high-pressure clamping structure. The electrolytic cell stack includes a plurality of pole plates and membrane electrodes that are alternately stacked in sequence. Titanium felt and carbon paper are respectively arranged on both sides of the membrane electrode, and a carbon paper pressing groove is arranged on the pole plate near the carbon paper side. The high-pressure clamping structure clamps the electrolytic cell stack, and the carbon paper is pressed into the carbon paper pressing groove. During the clamping installation, excessive compression of the carbon paper is avoided, thereby improving the service life of the water electrolytic cell. The carbon paper pressing groove controls the compression amount of the carbon paper, so that the compression of the carbon paper is always within a limit. The moderate compression of the carbon paper improves the mass transfer capacity of hydrogen while ensuring that the high-pressure water electrolysis hydrogen production device does not leak, thereby improving the performance of the water electrolytic cell.

The invention relates to a microfluid chip for enhancing mass transfer. The microfluid chip comprises a cover plate and a microchannel formed by combining the cover plate and a sheet-shaped substrate with a groove, a single unit flow channel is in a one-to-two, two-to-three, three-to-two and two-to-one flow channel mode, and eight times of opening and closing are carried out in total; according to the invention, through the design of a plurality of separating and combining structures, the switching of near-wall liquid levels is realized at the same time, and the condition that a granular catalyst, a biomacromolecule or a polymer material is easy to block in a microfluidic chip is improved; meanwhile, the runner lengths of the opening and closing channels are consistent, and the residence time distribution is reduced; as the mixing is strengthened mainly by forming the chaotic flow through multiple times of splitting and combining, the micro-channel size can still have a good mass transfer strengthening effect at a millimeter level, and the forming difficulty is greatly reduced compared with that of a micro-fluidic chip with strengthened mixing. The technical problems that the micro-channel reactor is easy to block and the equipment processing difficulty is high are solved, and the purposes of improving the chemical production efficiency, mixing multiple substances and transferring mass can be achieved.

The invention belongs to the technical field of synthesis of organic compounds, and particularly discloses a continuous production system and a production method of 1-(4-chlorphenyl)-3-pyrazole alcohol. The method is used for solving the problems of low production efficiency, high operation cost and danger and large wastewater discharge of a traditional intermittent hydrogen peroxide oxidation process. The production system comprises a raw material premixing tank, a conveying pump, an air source, an ejector, a reaction unit, a pH adjusting tank, a continuous filter, a temporary storage tank, a continuous dryer and an ion resin exchanger, the reaction unit comprises a plurality of static mixing tubular continuous flow reactors which are connected in series, static mixing elements are arranged in the static mixing tubular continuous flow reactors, and heat exchange jackets are arranged outside the static mixing tubular continuous flow reactors; heat exchange jackets or coil pipes are arranged on the outer side walls of the raw material premixing tank and the pH adjusting tank; and the ion resin exchanger is provided with a backwashing port. According to the invention, full-process continuous production is realized, green and safe preparation is realized, and the production efficiency, the product yield and the product purity are improved.

The invention relates to gradient hydrophilic and hydrophobic carbon paper and a preparation method thereof.The preparation method comprises the following steps that 1, pretreated carbon paper is soaked in nano-silica dispersion liquid, taken out, dried and subjected to heat treatment, and hydrophilic treated carbon paper is obtained; and (2) spraying hydrophobic modified silane dispersion liquid on the surface of one side of the carbon paper subjected to hydrophilic treatment, drying and then carrying out heat treatment to obtain the carbon paper with gradient hydrophilicity and hydrophobicity in the thickness direction. Compared with the prior art, the method has the advantages that gradient hydrophilic and hydrophobic properties are constructed in the thickness direction of the carbon paper, the water drainage and gas transmission properties of the carbon paper are effectively improved, the process is simple, and the cost is low.

The invention discloses an efficient low-carbon vertical tank supergravity mixed magnesium smelting device and method.The device comprises a furnace body and a supergravity solid-liquid mixing system, and the supergravity solid-liquid mixing system comprises a first-stage material gathering taper pipe fixedly arranged in the furnace body and a second-stage material gathering taper pipe provided with a discharging port; a liquid-solid mixing reaction material tank internally and fixedly connected with a solid raw material distributing plate is arranged above the first-stage material gathering taper pipe, the liquid-solid mixing reaction material tank is fixedly connected with a solid raw material feeding pipe provided with a solid raw material feeding vacuum valve, and the solid raw material feeding pipe is rotationally connected with the furnace body and connected with a transmission assembly. A liquid-state reducing agent atomizing disc is fixedly arranged in the liquid-solid mixing reaction material tank and is rotationally connected with a liquid-state reducing agent feeding pipe provided with a liquid-state reducing agent feeding vacuum valve; the furnace body is connected with the magnesium steam collecting system, the magnesium steam collecting system is connected with the vacuumizing system, and a slag outlet is formed in the bottom of the furnace body and connected with a sealing piece. According to the invention, the reaction efficiency is improved, the energy consumption is reduced, and energy conservation and emission reduction are realized.

The invention discloses a process for continuously synthesizing m-trifluoromethyl acetophenone oxime by adopting a microchannel reactor. The process comprises the following steps: reacting m-trifluoromethyl aniline with sodium nitrite and sulfuric acid to obtain a diazonium salt solution; the method comprises the following steps: adding a copper salt catalyst, acetaldoxime, sodium acetate and water into a temperature-controlled stirring kettle as an initial circular reaction solution, and regulating the pH value of the circular reaction solution in real time by adding alkali liquor; the method comprises the following steps: quickly mixing a diazonium salt solution, an organic extraction solvent and a circular reaction solution through a micro-mixer, carrying out reaction and product in-situ extraction on the obtained mixed solution in a micro-channel reactor, and then separating through a phase splitter to obtain a water phase and an organic phase; the water phase returns to the temperature control reaction kettle for continuous recycling, and the organic phase is subjected to post-treatment to obtain the m-trifluoromethyl acetophenone oxime. The method disclosed by the invention is simple in process, continuous in operation, short in reaction period, high in safety controllability and high in production efficiency, and effectively solves the problems in the intermittent kettle type process for preparing the m-trifluoromethyl acetophenone oxime by utilizing the m-trifluoromethyl aniline at present.

The present invention relates to a device and method for removing hydrogen sulfide from sulfur-containing produced water in oil and gas fields, comprising a pretreatment system and a hydrogen sulfide removal system; the pretreatment system is connected to the sulfur-containing produced water; the pretreatment system comprises a gravity sedimentation tank, a mixing tank, a flotation separator, a filter and a buffer tank connected in sequence, and the sulfur-containing produced water is connected to the gravity sedimentation tank; the hydrogen sulfide removal system comprises a hollow fiber supported liquid membrane assembly, a water purification tank and a receiving phase liquid tank connected in sequence; the hollow fiber supported liquid membrane assembly comprises a membrane shell and a hollow fiber supported liquid membrane bundle tube arranged from outside to inside; sealing baffles are respectively arranged on the two side ports of the membrane shell, the shell side is provided with a shell side inlet and a shell side outlet, and the tube side is provided with a tube side inlet and a tube side outlet; the tube side inlet is connected to the buffer tank, and the tube side outlet is connected to the water purification tank; the shell side outlet and the shell side inlet are connected through the receiving phase liquid tank. The present invention can make the extraction and stripping processes proceed simultaneously.

The present invention relates to the field of fuel cells, and in particular, provides a fuel cell double-catalyst layer cathode, a preparation method and a fuel cell. The fuel cell double-catalyst layer cathode comprises a first catalytic layer for being arranged on one side of a proton exchange membrane and a second catalytic layer for being arranged on one side of a gas diffusion layer; the first catalytic layer and the second catalytic layer are each independently a platinum-cobalt alloy catalytic layer based on a carbon carrier; the specific surface area of ​​the first catalytic layer is 500-900 m 2 / g, the secondary pore size is 20~50nm; the specific surface area of ​​the second catalytic layer is 50~150 m 2 / g, and the secondary pore size is 70-100nm. The present invention can take into account both the mass transfer capacity and the water retention capacity of the cathode catalyst layer of the fuel cell.

The invention belongs to the field of application of electro-catalytic materials, and particularly relates to a multi-element metal oxide integrated electrode and a preparation method thereof. The electrode is prepared by a one-step Joule thermal method and comprises the following steps: step 1, pretreating the surface of a carbon-based substrate by using a polyethyleneimine aqueous solution and drying; 2, dissolving the transition metal salt and precious metal salt hydrate in ethanol to obtain a precursor solution; 3, uniformly dripping the precursor solution on the surface of a carbon-based substrate for dipping, and carrying out vacuum drying; and 4, rapidly heating the carbon-based substrate by using electric Joule thermal equipment to prepare the catalytic electrode. The method is simple, the multi-metal oxide integrated electrode which is high in activity, low in cost and uniform in dispersion is rapidly synthesized in a short time, and the catalyst can effectively support efficient oxygen evolution reaction under acidic and alkaline conditions; the preparation method is suitable for large-scale industrial production of the electrolyzed water OER catalytic electrode, and can be widely applied to the application fields of electrolytic cells and fuel cells.

The invention provides a circulating biological filter based on packaged nitrifying bacteria and an operation method thereof.The circulating biological filter comprises a conical bottom area V1, a cylindrical reaction area V2 and a three-phase separation area V3, the bottom of the three-phase separation area V3 is communicated with the cylindrical reaction area V2, the bottom of the cylindrical reaction area V2 is communicated with the conical bottom area V1, and the conical bottom area V1 is communicated with the cylindrical reaction area V2. The three-phase separation area V3 is formed by a conical bottom inner cavity, the cylindrical reaction area V2 is formed by a reaction area inner cavity, and the conical bottom area V1 is formed by an overflow weir inner cavity. By optimizing the proportion of each part of the biological filter of the three-phase biological fluidized bed, the height-diameter ratio is reduced; and the flow guide cylinder and the flow guide cover are arranged, and air is utilized for pushing, so that an aerobic environment required by nitrifying bacteria can be ensured, the filler can be fully fluidized, the mass transfer effect is enhanced, and a good treatment effect on ammonia nitrogen pollutants in aquaculture tail water is achieved.

The invention relates to a device and method for preparing a magnesium / aluminum dissimilar metal joint, and relates to the technical field of welding metallurgy technology and material scientificity, the device comprises a welding table, a plate fixing assembly, a magnetic field assembly and a welding tool, a sealing plate is arranged on the welding table in a surrounding mode, and cooling water is poured into the sealing plate; the plate fixing assembly, the magnetic field assembly and a working head of the welding tool are all located below the liquid level. Trapezoid grooves are formed in the welding positions of the magnesium alloy and the aluminum alloy and filled with mixed powder of the magnesium alloy and the aluminum alloy according to a certain proportion, and component optimization is conducted on welding seams; the welding process is carried out underwater, a copper base plate is adopted, the temperature of a weld joint area in the welding process can be rapidly reduced and dispersed, a magnetic field is applied, under the stirring effect of electromagnetic force, molten plastic flowing metal has a better mass transfer effect on the microscale, element segregation is reduced, and therefore generation of magnesium-aluminum intermetallic compounds is restrained; and the cracking behavior in the welding process is reduced, so that the strength and the preparation efficiency of the magnesium / aluminum dissimilar metal joint are improved.