214 results about "Activated alumina" patented technology

The invention relates to a preparation method and application of a porous material for preparing methanol through carbon dioxide adsorption and conversion. When the material is prepared, firstly, 4, 4 '4' '-(1, 3, 5-triazine-2, 4, 6-trimethylene) triphenylamine and 1, 2-acenaphthequinone are treated in a mixed solvent containing dioxane / acetonitrile / 6M acetic acid, and AT-COF is obtained; further synthesizing by adopting an impregnation method to obtain IrRu-COF; and finally, uniformly mixing the active gamma-aluminum oxide and the IrRu-COF material to form a carrier dispersion liquid, and then carrying out PEI loading, vacuum impregnation, washing and drying to obtain the PEI functionalized gamma-Al2O3 / COF composite catalyst. The technical closed loop from low-concentration CO2 capture to solar driven conversion is realized, the process flow is simple, and the energy consumption is low.

The invention belongs to the field of hydrometallurgy, and particularly discloses a high-purity vanadium oxide electrode and a preparation method thereof. The method comprises the following steps: pre-treating the alkaline vanadium leaching solution by using an activated aluminum oxide adsorption column to obtain a pre-treated solution; adding a composite impurity removal agent taking modified lignosulfonate as a main agent into the pretreatment liquid for primary impurity removal to obtain primary impurity-removed filtrate; adding a calcium hydroxide suspension and a flocculating agent into the primary impurity-removed filtrate for secondary impurity removal to obtain secondary impurity-removed filtrate; purifying the secondary impurity-removed filtrate by using an ion exchange column to obtain a purified solution; ammonium salt is added into the purified liquid for vanadium precipitation, and ammonium metavanadate crystals are obtained; calcining the ammonium metavanadate crystal to obtain high-purity vanadium pentoxide; and preparing the high-purity vanadium oxide electrode by using the high-purity vanadium pentoxide. According to the scheme, the high-purity vanadium pentoxide is prepared by taking the alkaline vanadium leaching solution as a raw material through a multi-stage deep impurity removal process, and the high-purity vanadium oxide electrode is prepared by taking the alkaline vanadium leaching solution as the raw material.

The invention relates to the field of refractory materials, in particular to a dry ramming mass for an intermediate frequency furnace and a preparation method thereof.The dry ramming mass is prepared from, by weight, 45-55 parts of fused corundum, 8-12 parts of fused magnesia, 15-20 parts of tabular corundum, 3-5 parts of fused spinel, 3-4 parts of activated aluminum oxide, 1-2 parts of silicon carbide, 1-2 parts of silica sol and 0.5-1 part of boric acid. 3.5-4.5 parts of a binding agent and 3-5 parts of an anti-penetrating agent; wherein the anti-penetrating agent is chromium oxide coated nickel aluminate microspheres. The invention solves the two major problems of easy penetration and thermal shock peeling of the traditional furnace lining, is especially suitable for harsh smelting environments of high manganese steel, stainless steel and the like, and has long service life and convenience in construction.

The invention relates to a method for extracting lithium from a lithium-containing sodium aluminate solution and preparing lithium carbonate, and belongs to the technical field of lithium recovery. The method comprises the following steps: adding an extracting agent into a lithium-containing sodium aluminate solution, and carrying out extraction reaction to obtain a lithium-removed sodium aluminate solution and a lithium-rich extracting solution; carrying out reverse extraction on the lithium-rich extraction liquid by taking water as a reverse extraction agent to obtain a lithium-containing solution; adding activated aluminum oxide into the lithium-containing solution, and carrying out adsorption reaction to obtain solid-phase aluminum oxide; eluting the solid-phase aluminum oxide with acid to obtain a lithium-rich solution; and adding a carbon source into the lithium-rich solution, and sequentially precipitating, separating and washing to obtain lithium carbonate. According to the method, a complex impurity removal process does not need to be carried out on the lithium-containing sodium aluminate solution, the high-concentration lithium salt solution is obtained after the lithium ions are directly extracted from the lithium-containing sodium aluminate solution and then are subjected to reverse extraction, adsorption and desorption, and industrial-grade lithium carbonate can be obtained by supplementing a carbon source, so that the preparation cost of the lithium carbonate is greatly reduced. The method has the advantages of good selectivity, high recovery rate, cyclic continuous production, economy and environmental protection.

The invention relates to a chlorine dioxide sustained-release ball, which relates to the technical field of environmental protection and disinfection, and comprises an activated alumina ball and an inorganic porous layer from inside to outside, wherein the activated aluminum oxide ball is loaded with sodium chlorite and a porous film, and the inorganic porous layer is loaded with the porous film. The chlorine dioxide sustained-release ball disclosed by the invention realizes the goals of high load, long period, constant-speed release and stable physical form.

The present invention discloses a vertical continuous calcination furnace for activated alumina balls, which comprises a vertical furnace body. The top of the furnace body is a feed inlet, and the bottom is a discharge outlet. A hot air distributor is installed in the middle of the vertical furnace body. The hot air distributor is provided with a number of air distribution holes, and the hot air distributor is connected to a burner. The burner provides hot air for the interior of the vertical furnace body through the hot air distributor. An air extraction port is provided at the top of the vertical furnace body, and the air extraction port is connected to an induced draft fan. The hot air enters downward from the middle and lower part of the furnace body and turns back upward under the action of the induced draft fan to heat the balls.

The present invention discloses a method for preparing dimethyl disulfide by methyl mercaptan sulfidation, which includes: (1) loading a yttrium-modified alumina catalyst in a shell-and-tube fixed-bed reactor, and then filling a solution of dimethyl disulfide and / or dimethyl polysulfide into the shell-and-tube fixed-bed reactor; (2) mixing liquid methyl mercaptan and liquid sulfur evenly through a pipeline mixer and continuously introducing them into the bottom of the shell-and-tube fixed-bed reactor to carry out a sulfidation reaction to generate a crude sulfide including dimethyl disulfide, dimethyl polysulfide, and hydrogen sulfide gas; (3) successively passing the crude sulfide through a first-stage, a second-stage, and a third-stage distillation column to remove hydrogen sulfide, methyl mercaptan, and dimethyl polysulfide respectively, so as to obtain high-quality dimethyl disulfide. The present invention uses a yttrium-modified activated alumina catalyst, which can greatly improve the activity of the catalyst and its selectivity for dimethyl disulfide, and make the single-pass conversion rate of dimethyl disulfide reach more than 90%.

The present invention relates to a carbon-coated cloth for efficiently absorbing VOCs in the air and a preparation method thereof, comprising: ball-milling a mixture of first activated carbon and water until the activated carbon particles are evenly distributed, adding a modifier, and dispersing the mixture through ultrasonic impregnation to obtain a spray liquid; spraying the spray liquid onto a receiving substrate and drying it to obtain a highly absorbent skeleton layer; uniformly mixing a second activated carbon and activated alumina impregnated with an active component to obtain an adsorbent material; laying a first hot-melt adhesive web on the unsprayed surface of the highly absorbent skeleton layer, hot-pressing the surface, and then flattening the adsorbent material, followed by laying a second hot-melt adhesive web and hot-pressing and fixing it, and finally laying a melt-blown cloth to obtain the carbon-coated cloth. The present invention achieves high performance in high-humidity environments by disposing coconut shell activated carbon having a pore structure dominated by mesopores and carrying highly absorbent groups upstream of the receiving substrate. Furthermore, the moisture content of the VOCs in the mixed gas decreases after passing through the receiving substrate, and the active component also facilitates their adsorption on the microporous activated carbon.

The utility model discloses an activated aluminum oxide quantitative conveying device, and relates to the field of conveying devices.The activated aluminum oxide quantitative conveying device comprises a charging barrel, a discharging assembly used for controlling the weight is arranged on the charging barrel, the discharging assembly comprises a discharging pipe fixedly connected to the bottom end of the charging barrel, and a first electromagnetic valve is installed at the bottom end of the discharging pipe; the upper end and the lower end of the side wall of one side of the discharging pipe are fixedly connected with first fixing blocks, and a threaded rod is rotatably connected between the two first fixing blocks. Through cooperative arrangement of the threaded rod, the quantitative cylinder, the moving block and other structures, during use, the threaded rod is driven to rotate through the rotating assembly, the position of the quantitative cylinder on the discharging pipe is adjusted, and the capacity of the quantitative cylinder is adjusted; then the first electromagnetic valve is opened to convey materials in the charging barrel into the quantitative barrel through the discharging pipe, then the first electromagnetic valve is closed, the second electromagnetic valve is opened to discharge the materials in the quantitative barrel for conveying, and the problem that the applicability is reduced due to the fact that the one-time conveying amount of activated aluminum oxide cannot be controlled according to requirements is avoided as much as possible.

This application relates to the field of organic synthesis technology, specifically disclosing a process for preparing tert-butyl vinyl ether. The raw materials include solid tert-butanol, acetylene, tetrahydrofuran solvent, and potassium hydroxide catalyst, supplemented with auxiliary materials such as type 3A molecular sieves and activated alumina adsorbents. The preparation method involves: after dehydration and purification of the raw materials, the materials are introduced into a reaction vessel; temperature and pressure are controlled, and the reaction endpoint is monitored using an infrared spectrometer; byproducts are quenched and acetylene is recovered; the process involves multi-stage condensation, water washing to remove impurities, distillation separation, and solvent purification and recycling, with simultaneous integration of waste heat recovery and continuous material feeding. The tert-butyl vinyl ether prepared by this process, as an important fine chemical intermediate, can be used in coatings, adhesives, and polymer material modification, possessing advantages such as high purity and good stability. The preparation method achieves efficient utilization of materials and energy through multi-stage synergistic linkage, combining the advantages of green environmental protection, continuous and stable operation, and high resource utilization.

The invention belongs to the technical field of purification and regeneration of industrial oil products, and relates to a composite adsorbent for regeneration of phosphate fire-resistant oil and a preparation method of the composite adsorbent. The catalyst comprises the following components in percentage by mass: 40-60% of a mesoporous silicon-aluminum molecular sieve, 20-35% of surface modified activated aluminum oxide, 10-20% of organic alkali functionalized silica gel and 3-8% of a metal deactivator. According to the invention, the overall adsorption capacity and selectivity of various degradation products in the phosphate fire-resistant oil are obviously improved, and the adsorption loss of effective components of the base oil is effectively reduced.

The invention discloses a synthesis process of tungsten hexafluoride, and relates to the technical field of special gas synthesis. The process comprises the following steps: mixing ammonium fluoride and hydrofluoric acid to prepare an activation solution, carrying out ultrasonic activation treatment on tungsten powder to obtain pretreated tungsten powder, and reacting the pretreated tungsten powder with fluorine gas at a certain temperature and pressure to prepare a liquefied crude product tungsten hexafluoride; the preparation method comprises the following steps: by taking aluminum sec-butoxide and the like as raw materials, carrying out sol-gel and ethanol supercritical drying and calcining to prepare highly porous activated aluminum oxide; gasifying the crude tungsten hexafluoride, adsorbing with activated aluminum oxide, and rectifying to obtain purified tungsten hexafluoride liquid; and finally, dissolving in liquid sulfur dioxide, treating under illumination with the wavelength of 395nm, and carrying out distillation separation to obtain high-purity tungsten hexafluoride. According to the method, the activation pretreatment is combined with multi-stage purification, so that the purity and the synthesis efficiency of tungsten hexafluoride are remarkably improved.

The application discloses a novel white clay bed, which comprises a bed body (6), a liquid inlet (1) arranged at the lower part of the bed body (6), a liquid outlet (7) arranged at the upper part of the bed body (6), a liquid distributor (2) arranged above the liquid inlet (1), a coalescence water removal filler (3), a baffle (4) and a honeycomb-shaped integrated regenerant (5) arranged above the liquid distributor (2) in sequence. The novel white clay bed can eliminate the secondary powder formed by the mutual friction of active alumina particles in the white clay bed, greatly reduce the water entrained by the working liquid into the white clay bed, prolong the service life of the regenerant and be favorable to the stable operation of a hydrogen peroxide device.

The invention relates to a three-way catalyst as well as a preparation method and application thereof. The three-way catalyst comprises a carrier and an active coating coated on the surface of the carrier, the active coating comprises a bottom layer, a middle layer and an upper layer from inside to outside; the bottom layer comprises an oxygen storage material layer, and the oxygen storage material layer comprises activated aluminum oxide and a rare earth oxygen storage material; the middle layer comprises a Pd coating, and the upper layer comprises a Pt-Rh-Ru coating. The three-way catalyst provided by the invention adopts a three-layer coating structure, so that the poisoning effect of sulfur in gas on noble metal palladium is effectively reduced, and the performance and durability of the catalyst are greatly improved. Activated aluminum oxide and a rare earth oxygen storage material are selected as bottom layer materials of the catalyst, the oxygen storage performance of the catalyst is greatly improved, and the catalyst has obvious performance advantages when coping with engine loads with large air-fuel ratio fluctuation.

The invention belongs to the technical field of refractory materials, and particularly provides a nano-sol-based low-carbon environment-friendly refractory castable and a preparation process thereof, and the nano-sol-based low-carbon environment-friendly refractory castable comprises composite aerogel powder, modified nano-silica sol, compact corundum, brown corundum, white corundum, alumina, silicon carbide, activated alumina and spherical asphalt. The low-carbon environment-friendly refractory castable based on the nano sol has the advantages of being low in carbon, environmentally friendly, excellent in heat insulation performance, high in thermal shock resistance and high in mechanical strength, and is suitable for high-temperature industries such as metallurgy and building materials.

The invention discloses a neutral ramming material for an intermediate frequency furnace, and belongs to the technical field of steel smelting. Comprising the following raw materials in parts by weight: 35-40 parts of microporous sintered corundum particles with the particle size of 3-5mm, 35-40 parts of microporous sintered corundum particles with the particle size of 1-3mm, 20-25 parts of magnesium aluminate spinel particles with the particle size of 1-3mm, 9-11 parts of activated aluminum oxide micro powder, 5-7 parts of modified cordierite fine powder, 1-2 parts of pretreated boron nitride, 0.5-1.5 parts of nano aluminum oxide and 0.2 part of nano aluminum oxide. 0.4 part by weight of zinc borosilicate glass powder, 0.6-0.8 part by weight of high-temperature organic silicon resin and 0.05-0.1 part by weight of anti-burst fiber. The prepared neutral ramming material for the intermediate frequency furnace has good compression strength, thermal shock resistance and slag resistance.

The application discloses a kind of halloysite-based adsorbents and its preparation method and application, belong to fluoride removal agent material technical field, soluble Al 3+ Salt solution is dropped into 50~95 ℃ halloysite and alkali metal Cl ‑ In the suspension formed by salt solution, pH value is controlled to be 8~11, co-precipitation reaction, Al 3+ And Cl ‑ Form [AlCl4] ‑ Coordination, hydrolysis boehmite type alumina and load in halloysite, obtain composite product;The composite product is calcined at 400~700 ℃, and halloysite-based adsorbent is obtained.The crystal form of the alumina loaded under the condition of pH=8~11 synthesized in the application is boehmite, and it can be converted into active alumina with relatively large adsorption activity to fluoride ion by calcining at 400~700 ℃, and the active alumina is mainly loaded in the inner / outer tube of halloysite, which is a wormhole porous structure, and the loading of active alumina improves the micropore ratio of the adsorbent, thereby improving the adsorption performance.

Described is a catalyst obtained by supporting magnesium and cerium on activated alumina, firing same to immobilize the metals, and then impregnating same with palladium and performing reduction thereon, and is applied, when hydrogen peroxide is prepared by means of an anthraquinone process, to operation solution regeneration or hydrogenation, and thus an efficient regeneration conversion rate or synthesis yield is achieved.

The present invention discloses an eggshell-type magnesia-aluminum spinel hollow sphere and a preparation method thereof; after electrofused magnesia, activated alumina powder and an additive are ball-milled and premixed, using polystyrene spheres as spherical supports, phenolic resin solution is added, and according to the concentration of the phenolic resin solution and the stirring speed, the thickness of the resin layer on the surface of the polystyrene spheres is jointly controlled. By controlling the particle size of the ball-milled premix, the thickness of the shell layer is controlled; it is formed and sieved in a granulator, and then through steps such as drying and heat treatment, magnesia-aluminum spinel hollow spheres are synthesized at low temperature. The present invention uses inexpensive and easily obtainable raw materials, has the characteristics of low cost and simple preparation process, and the prepared magnesia-aluminum spinel hollow spheres have excellent high-temperature resistance.

The utility model relates to the technical field of drying machines, in particular to a drying machine capable of easily removing water vapor, which comprises a machine body, a partition plate is fixedly mounted in the machine body, through holes are formed in the surface of the partition plate, and a shell is fixedly mounted in a cavity between the partition plate and the machine body. According to the drying device, the through holes are formed in the partition plate, and the heating pipe is installed below the partition plate, so that hot air can uniformly flow through the whole drying area, the removal efficiency of water vapor is improved, and uniform distribution of temperature in the drying area is ensured, so that evaporation of water on the surface of an object is accelerated; evaporated water vapor is treated through the absorption layer on the top of the drying machine, the absorption layer adopts activated aluminum oxide as a drying agent and has strong adsorption capacity, the activated aluminum oxide drying agent can efficiently absorb moisture in air and prevent the water vapor from flowing back to a drying area, and therefore the low-humidity environment in the drying cavity is maintained, it is ensured that the moisture is effectively discharged, and the drying efficiency is improved. Therefore, drying of the object is accelerated.

The invention discloses a calcium hexaluminate repairing material, a preparation method thereof and application of the calcium hexaluminate repairing material in repairing of a water beam or a stand column of a steel rolling heating furnace. The calcium hexaluminate repairing material comprises a base material, an additive and water, each 100 parts by mass of the base material comprises the following raw materials: 70-80 parts by mass of calcium hexaluminate, 5-15 parts by mass of activated alumina micro powder, 10-20 parts by mass of calcium aluminate cement and 4-9 parts by mass of aluminum dihydrogen phosphate; the additive comprises a water reducing agent accounting for 0.1-0.2% of the mass of the base material; and the mass of the water is 10-20% of the mass of the base material. The calcium hexaluminate repairing material provided by the invention solves the problems of pouring construction, long repairing time and the like after the existing heating furnace water beam is damaged, has the advantages of high strength and low linear change rate, can reduce the consumption of refractory materials, greatly shortens the repair cycle, meets the requirement of fast-paced production of steel mills, and has wide application prospects. The method is of great significance in improving the production efficiency and reducing the energy consumption and carbon emission of the heating furnace.

The application discloses a long-acting antibacterial adsorption filler and a preparation method thereof, and comprises the following steps: S1, preparation of composite activated alumina; S2, preparation of aminated composite alumina; S3, preparation of organically modified composite alumina; and S4, preparation of the long-acting antibacterial adsorption filler. The long-acting antibacterial adsorption filler is prepared by loading cerium and bismuth composite oxides on an activated alumina substrate, and then bridging with a silane coupling agent, and sequentially introducing maleic anhydride, 2,3-epoxypropyl trimethyl ammonium chloride and 2-mercaptothiazoline, so that the finally-prepared filler integrates multiple functions such as physical adsorption, chemical adsorption, contact sterilization and slow-release sterilization. The method effectively solves the technical problems of single function of a traditional adsorbent, inability to sterilize and easy secondary pollution, and achieves omnibearing and long-acting purification of indoor air pollutants.

This invention discloses a method for preparing a composite-layer reinforced long-life zirconia sizing nozzle. The method involves uniformly mixing yttrium-stabilized zirconia fine powder, high-purity calcium hexaaluminate fine powder, activated alumina fine powder, and calcium aluminate cement, adding deionized water and stirring until homogeneous, casting into a mold, demolding, and drying to obtain a composite layer preform. The composite layer preform is then isostatically pressed, sintered, cooled, crushed, ball-milled, and sieved to obtain composite layer powder. Activated alumina fine powder, yttrium oxide fine powder, calcium aluminate cement, and the composite layer powder are then uniformly mixed, water is added, and the mixture is rolled to obtain a mud. This mud is then bonded to the inner wall of the nozzle body's inner bore, dried, isostatically pressed, and sintered to obtain the finished product. The composite layer in this invention has the characteristics of being non-wetting and non-reactive with molten steel. The prepared nozzle exhibits excellent thermal shock resistance, erosion resistance, scour resistance, and high strength, improving the cleanliness of molten steel during continuous casting and contributing to the improvement of billet quality.

The invention belongs to the technical field of nano powder material preparation, and particularly relates to a method for preparing nano tungsten powder from activated aluminum oxide and nano tungsten powder.The method comprises the following steps that S1, tungsten oxide and activated aluminum oxide balls are evenly mixed according to the mass ratio of 1: (1-2), and a premix is obtained; s2, heating and reducing the premix in a hydrogen atmosphere to obtain a mixture; s3, the mixture is screened, and nano tungsten powder and activated aluminum oxide balls are obtained; the high water absorption performance of activated aluminum oxide is utilized, water vapor generated in a system is efficiently adsorbed, and it is ensured that the particle size of tungsten powder is stably controlled at the nanoscale; the porous structure can physically block mutual contact and combination of nucleated tungsten particles, and agglomeration of tungsten powder is effectively reduced; the method has the advantages of high process compatibility, capability of fine adjustment based on the existing process, controllable raw material cost, better economical efficiency, no complex process in the operation process and easiness in realization of large-scale stable production.

This invention relates to the field of deactivated alumina regeneration technology, and discloses a method for regenerating deactivated alumina and its application: (1) cleaning deactivated alumina by contacting it with a cleaning solvent to obtain purified alumina I; (2) purging the purified alumina I by contacting it with water vapor to obtain purified alumina II; (3) soaking the purified alumina II in an alkaline solution to obtain regenerated alumina. The method for regenerating deactivated alumina provided in this invention yields regenerated alumina with high activity and low production cost, effectively reducing environmental pollution problems caused by the treatment of deactivated activated alumina, and has good social benefits, making it suitable for industrial promotion.

The invention provides a rare earth co-doped high-toughness alumina-based ceramic ball and a preparation method thereof, and relates to the field of ceramic materials. The preparation method of the rare earth co-doped high-toughness alumina-based ceramic ball comprises the following steps: raw material pretreatment, ingredient mixing, dispersion granulation, molding and sintering. The ingredient mixing method comprises the following steps: uniformly mixing the activated alumina powder, the yttrium-stabilized zirconia, the compound additive and the La source to obtain a premix; the La source is at least one of the following components: La2O3, La (NO3) 3 and LaCl3; the compound additive is prepared from rutile type titanium dioxide and cerium dioxide. According to the preparation method of the rare earth co-doped high-toughness alumina-based ceramic ball, on the premise of low production cost, the phase distribution of a ceramic material can be optimized, the strength, toughness and abrasion resistance of the large-size ceramic ball are synchronously improved, and the volume density of the ceramic ball is stably kept to be not lower than 3.80 g / cm < 3 >.

The invention relates to the technical field of tert-butyllithium preparation, in particular to a tert-butyllithium preparation method which comprises the following steps: preparing raw materials, dissolving lithium and washing oil, mixing the raw materials to start reaction, dropwise adding a modifier, carrying out heat preservation treatment, cooling, settling and taking clear liquid. According to the method, trace impurities on the surface of lithium are removed in the pretreatment link, the PVP coating can block contact of water, oxygen and lithium in a long-acting mode, lithium is prevented from going bad in the earlier stage of storage and reaction, and meanwhile the compatibility of lithium and organic solvents such as n-pentane is enhanced; the interference of impurities on the reaction can be eliminated in a high-purity state of the chlorinated tert-butane, byproducts such as lithium tert-butoxide are prevented from being generated, the moisture in the system is strictly limited by deep dehydration, a stable anhydrous environment is provided for synthesis of the tert-butyllithium, and the reaction efficiency is guaranteed; the operation of deep dehydration and impurity removal by activated aluminum oxide creates a high-cleanliness solvent system for the reaction, avoids the action of water and polar impurities with tert-butyllithium or reaction intermediates, and prevents product decomposition or impurity generation.

The invention discloses an activated aluminum oxide modified activated carbon fiber felt and a preparation method and application thereof, and belongs to the technical field of adsorption materials, and the preparation method comprises the following steps: S1, preparing an activated activated carbon fiber felt; s2, adding urea and aluminum chloride hexahydrate into deionized water, stirring and dissolving, then adding the activated activated carbon fiber felt, stirring and mixing uniformly, transferring into a reaction kettle for reaction, cooling, taking out, washing and drying to obtain an aluminum oxide precursor modified activated carbon fiber felt; s3, transferring the alumina precursor modified activated carbon fiber felt into a tubular furnace, performing annealing treatment in a nitrogen atmosphere, and cooling to room temperature to obtain an activated alumina modified activated carbon fiber felt; the preparation method is simple and easy to implement, the used materials are wide in source and low in cost, and the prepared activated aluminum oxide modified activated carbon fiber felt shows excellent fluorine ion removal rate and removal efficiency on a water body containing low-concentration fluorine ions and has wide application prospects.

This invention relates to the field of compound preparation technology and discloses a method for the asymmetric synthesis of R-6,8-dichlorooctanoate by hydrogenation catalyzed by a composite catalyst. The method includes the following steps: S1. Activation of the alumina support; S2. Preparation of the composite catalyst; S3. High-pressure hydrogenation; S4. Chlorination. The activated alumina support and ruthenium-palladium mixed catalyst of this invention exhibit high selectivity (over 99%) and optical purity (over 98%) in the hydrogenation reduction of 6-carbonyl-8-chlorooctanoate to R-6-hydroxy-8-chlorooctanoate under suitable temperature and pressure. The activated alumina support and ruthenium-palladium mixed catalyst also demonstrate high inhibition of dechlorination and ester reduction during carbonyl reduction under suitable temperature and pressure. The high-pressure hydrogenation process provides a novel process route for the carbonyl reduction of compounds. The use of the same solvent in both high-pressure hydrogenation and chlorination reduces the difficulty of subsequent post-processing and makes the method more suitable for industrial production.

The utility model relates to the technical field of water treatment, in particular to a multi-stage adsorption filter gradient filling device which comprises a filling shell, a charging assembly, an electric telescopic column and a connecting assembly, the filling shell is internally connected with the inner shell; the charging assembly is connected to the filling shell. The loading assembly comprises a motor, a rotating shaft rod and a spiral blade; the driving end of the motor is connected with a rotating shaft rod which rotationally penetrates through the filling shell, and the periphery of the rotating shaft rod is connected with spiral blades which are connected into the inner shell. The electric telescopic columns are connected to the two sides of the filling shell. The connecting assembly is connected to the filling shell; the connecting assembly comprises a mounting frame, two ends of the mounting frame are connected with mounting blocks respectively, the mounting blocks are connected with a filling shell, and the filling shell is connected with the inner wall of the inner shell. According to the gradient filling device, activated aluminum oxide, zeolite and biochar are filled in a spiral layered manner and are sequentially conveyed into the filter, so that multiple pollutants are synergistically removed, the raw material filling efficiency is improved, the water treatment working efficiency is improved, and the practicability of the gradient filling device for the multi-stage adsorption filter is conveniently improved.