2999 results about "Calcination" patented technology

An integrated carbon honeycomb structure material and its preparation method are disclosed, belonging to the field of carbon materials technology. Based on a co-sacrificial template low-temperature pyrolysis strategy, the target material can be obtained through three main steps: preparation of a metal salt-colloidal microsphere template precursor, precursor pressing and molding, and subsequent calcination and carbonization. This technology has the characteristics and advantages of simple preparation process, regular and controllable macroscopic structure of the sample (such as shape, area, and thickness), rich and tunable chemical composition, and three-dimensional interconnection of graphene carbon matrix. It has great application potential in many fields such as electrochemical energy storage, catalysis, gas separation, adsorption, and electromagnetic shielding.

The invention discloses a high-content steel slag-based functionalized nano-composite cementing material and a preparation method thereof, and belongs to the technical field of solid waste resource comprehensive utilization. The nano composite cementing material is prepared from the following raw materials in parts by mass: 50 to 65 parts of steel slag, 10 to 20 parts of fly ash, 10 to 25 parts of carbide slag, 8 to 15 parts of desulfurized gypsum, 0.3 to 1.0 part of nano silicon dioxide and 0.003 to 0.03 part of silane coupling agent. On the basis of a solid waste synergism theory and an internal alkali excitation effect, quaternary solid wastes such as steel slag and fly ash are optimized and compounded by adopting methods of mechanical-thermal activation, addition of modified nano silicon dioxide, synergistic gelling between solid wastes and the like; the paint is prepared through gradient grinding and a medium-temperature wet curing process. The preparation method is simple, high-temperature calcination is not needed, cement clinker and exogenous excitant do not need to be added, the obtained cementing material can replace part of cement to be applied to the fields of road bases, mine filling, low-carbon building material products and the like, resource utilization and high-value utilization of regional bulk industrial solid waste can be achieved, and carbon emission and production cost are effectively reduced.

The invention discloses a preparation method of an In2O3-Cu-Cu2O ternary heterojunction catalyst and a preparation method of the In2O3-Cu-Cu2O ternary heterojunction catalyst. The method comprises the following steps: at room temperature and normal pressure, firstly, dissolving indium chloride tetrahydrate in a mixed solvent of ethylenediamine-ethylene glycol (the volume ratio is 1: 20-1: 30) and dihydric alcohol amine to obtain a homogeneous solution; then transferring the solution to a hydrothermal kettle, adding deionized water and Cu2O powder with different volumes, and carrying out hydrothermal crystallization at 160-200 DEG C for 10-14 hours; and centrifuging the obtained precipitate, alternately washing with water and alcohol for 2-3 times, carrying out vacuum drying at 60 DEG C for 5-7 hours, heating to 600 + / -10 DEG C at a speed of 3-5 DEG C / min in an N2 atmosphere, calcining for 3 hours, and cooling along with a furnace to obtain a target product. By adjusting the adding amount of the deionized water, the mass proportion of the three phases of In2O3, Cu and Cu2O can be continuously adjusted and controlled, and controllable preparation from'rich copper 'to'rich cuprous oxide' and'stable ternary 'is achieved.

This invention discloses a method for preparing a CuZnAlGa-based layered double hydroxide (TLH)-derived catalyst for methanol production from carbon dioxide-rich syngas. Using Cu, Zn, Al, and Ga metal salts as precursors, Na₂CO₃ and NaOH as precipitants, and a mixed alcohol-water solution as an auxiliary solvent, co-precipitation is performed under controlled temperature and pH to obtain a LDH-like catalyst precursor. After high-temperature calcination and in-situ reduction in a hydrogen atmosphere, a layered framework structure of Cu nanoparticles immobilized by oxides is obtained. The LDH-like structure provides lattice confinement, preventing Cu particle aggregation, and the interaction between Cu and the oxides enhances the catalyst surface's adsorption capacity for CO and CO₂, thereby improving the activity and stability of methanol production from carbon dioxide-rich syngas.

The invention provides a biochar composite porous material for heavy metal contaminated soil remediation and a preparation method and application of the biochar composite porous material. The preparation method comprises the steps that biomass raw materials are subjected to high-temperature pyrolysis carbonization and then smashed, ground and sieved, and biochar powder is obtained; dispersing in a phosphoric acid solution to obtain a biochar solution, and filtering, washing and drying after a hydrothermal activation reaction to obtain activated biochar; dispersing in a chitosan solution, carrying out ultrasonic oscillation, filtering, washing and drying to obtain modified charcoal; mixing sodium bentonite, attapulgite and deionized water, uniformly mixing the modified charcoal, the functional slurry and a sodium carboxymethyl cellulose solution to obtain composite slurry, performing compression molding to obtain a green body, and then drying and calcining the green body. The biochar composite porous material prepared by the invention can simultaneously play multiple roles of physical adsorption, chemical chelation, ion exchange and the like in a heavy metal contaminated soil treatment process, so that efficient fixation of various heavy metal ions is realized.

The invention belongs to the technical field of petroleum processing, and particularly relates to a catalyst and a preparation method and application thereof. The raw materials of the catalyst comprise a metal active component, a carrier and an auxiliary agent, the metal active component is sulfides of Mo and Ni elements, the carrier is spherical gamma-Al2O3 of 0.5-1 mm, and the auxiliary agent is P; the carrier is modified by using the metal active component and the auxiliary agent to serve as the catalyst. The high-activity catalyst is synthesized by adopting the strategy of changing the roasting temperature, adding the additive for doping modification and changing the molar ratio of metal active components, the additive is combined with surface aluminum atoms, the framework strength is enhanced, pore channel collapse caused by acid / water erosion is reduced, the water resistance and acid resistance of the catalyst are improved, and the catalytic reaction activity is further improved. The catalyst disclosed by the invention is accurate and controllable in structure, can be synthesized in batches, and can be applied to the co-catalytic hydrogenation process of biomass pyrolytic oil and / or a model compound thereof and petroleum distillate oil and / or VR.

The invention belongs to the technical field of solid waste concrete, and discloses fireproof sound-insulation heat-preservation light-weight high-strength all-solid waste concrete and a preparation method thereof.The fireproof sound-insulation heat-preservation light-weight high-strength all-solid waste concrete is prepared from an all-solid waste fireproof cementing material, all-solid waste light aggregate, water and a functional additive; the all-solid-waste fireproof cementing material comprises an alkaline activator component and an active powder component, the alkaline activator component comprises red mud and carbide slag in a mass ratio of (1.5-2.5): 1, and the active powder component comprises granulated blast furnace slag and low-temperature activated calcined coal gangue powder in a mass ratio of (1.0-1.8): 1; the all-solid-waste lightweight aggregate comprises coarse aggregate and fine aggregate in a mass ratio of (1-1.5): 1, wherein both the coarse aggregate and the fine aggregate comprise high-temperature expanded and roasted coal gangue lightweight aggregate; wherein the low-temperature activated and calcined coal gangue powder is obtained by performing gradient temperature control calcination on coal gangue at 650-800 DEG C and then grinding the coal gangue until the specific surface area is greater than or equal to 500m < 2 > / kg; the high-temperature expanded and roasted coal gangue lightweight aggregate is obtained by roasting and expanding coal gangue at 1100-1300 DEG C and then screening and grading.

The invention discloses a high belite iron aluminate cement clinker, which is prepared from the following raw materials in parts by weight: 39 to 73 parts of carbide slag, 8 to 37 parts of low-grade bauxite, 10 to 16 parts of ardealite, 1 to 31 parts of fly ash and 3 to 9 parts of steel slag. According to the cement clinker, the resource utilization rate of industrial solid waste in cement preparation can be remarkably increased, and dependence on natural raw materials and high-grade raw materials is reduced; impurities in various solid wastes can be used as in-situ mineralizing agents and activating agents, and on the basis of realizing high-added-value resource utilization of various industrial solid wastes and low-grade bauxite, efficient synthesis of target minerals at a relatively low temperature is promoted; and gradient temperature control calcination and gradient cooling processes are further combined, so that sufficient crystallization and development of a target mineral phase can be effectively promoted, a clinker microstructure is optimized, excellent early strength and continuously increased later strength of the cement are ensured, and the common problems of strength shrinkage and the like of the traditional solid waste-based cement can be effectively avoided.

The invention relates to the technical field of lime shaft kilns, in particular to a full-automatic Kawasaki rotating lime shaft kiln device, and aims to solve the problems that during combustion of an existing lime shaft kiln, due to the fact that flame heat is concentrated on a local part, a disordered and uniform temperature field cannot be formed, and the calcination temperature of limestone is not uniform; limestone processing is achieved through the combustion mechanism on the supporting seat, the soaking assembly in the thermal insulation shell guides materials and cooperates with the combustion assembly for preheating, a flame jet device of the combustion assembly jets flames, the flames act with heating gas blown out by the high-pressure air pump to form a uniform temperature field, and the material guiding plate guides the materials to enter the rotating processing part. And the processing component disperses the materials through the rotating and material uniformizing assembly, so that the limestone is uniformly heated, and the uniform effect during limestone calcination is improved.

The application relates to a continuous macro-preparation device and method of a soft and elastic ceramic superfine fiber material, which sequentially comprises a feeding and liquid preparation system, a multi-jet uniform electrostatic spinning system, a low-temperature calcination system and a winding system. Raw materials are mixed, low-temperature dispersed and vacuum concentrated to obtain a sol; the sol and a polymer flow into a polymer mixing device to be mixed and bubble removed; the mixed sol flows into an inorganic component content control device to be pumped by negative pressure to obtain a spinning solution; the spinning solution flows into a multi-jet electrostatic spinning module to adjust and control the temperature, humidity and multi-directional differential speed during spinning to obtain a fiber membrane material or a fiber flake material; the fiber material is sequentially transmitted to a drying area, a microwave pretreatment area, a polymer removal area, an oxygen-poor atmosphere heat treatment area and a cooling area to be calcined in multiple temperature zones to obtain the soft and elastic ceramic superfine fiber material; and winding and packaging are realized to realize the continuous macro-manufacture of the soft and elastic ceramic superfine fiber material.

The utility model discloses a lepidolite spodumene roasting flue gas multi-pollutant efficient treatment device which comprises a high-temperature dust removal and denitration integrated tower, a fan, a flue gas deacidification tower and a flue gas heat exchanger, the high-temperature dust removal and denitration integrated tower is communicated with a kiln tail of a roasting kiln, and a cooling section of the flue gas heat exchanger is communicated with the high-temperature dust removal and denitration integrated tower and the fan. Flue gas is subjected to heat exchange in the cooling section and then conveyed to the flue gas deacidification tower through a fan, a gas outlet of the flue gas deacidification tower is communicated with the heating section of the flue gas heat exchanger, the flue gas is subjected to heat exchange with flue gas of the high-temperature dust removal and denitration integrated tower in the flue gas heat exchanger to be heated, and the flue gas is discharged through a chimney communicated with the heating section on the flue gas heat exchanger. The device disclosed by the utility model can be used for cooperatively treating various pollutants including dust, SO2, HF, HCL, nitrogen oxides, dioxin, heavy metals and the like, so that high-efficiency treatment on flue gas is realized, and good economic benefits are achieved.

The invention discloses a vanadium oxide-based supported platinum catalyst and a preparation method and application thereof, and the preparation method comprises the following steps: a) carrying out high-temperature heat treatment on a V precursor to obtain orange V2O5 carrier powder; b) adding V2O5 powder, a Pt metal precursor and a sacrificial reagent into the solution, carrying out ultrasonic treatment, stirring, and reacting under the irradiation of a xenon lamp to obtain a dark brown suspension; c) centrifuging, washing, drying, grinding and roasting the dark brown suspension to obtain dark brown powder; and d) carrying out three times of high-temperature heat treatment on the dark brown powder under different protective gases, and sequentially carrying out three processes of oxidation, reduction and partial oxidation to obtain the vanadium oxide-based platinum-loaded catalyst. The catalyst prepared according to the invention is applied to a carbon monoxide oxidation reaction, and has the advantages of excellent catalytic performance, long-time stability and good recycling stability at a high space velocity.

The invention relates to a nano silicon carbide whisker and a preparation method thereof, and the preparation method comprises the following steps: (1) carrying out acid process treatment on fly ash by using an acid solution, so that the content of key impurity elements in the fly ash accounts for 2-11% of the total mass of the treated fly ash, and obtaining acid-treated fly ash; (2) mixing the acid-treated fly ash with a first carbon source to obtain a mixture; and (3) covering the mixture with a second carbon source, roasting in a reducing atmosphere to obtain a roasted material which comprises a nano silicon carbide whisker layer and a total impurity layer positioned below the silicon carbide whisker layer, and removing the total impurity layer to obtain the nano silicon carbide whisker. According to the preparation method, the low-cost fly ash is taken as a raw material, the advantages of low preparation cost and relatively high product yield can be taken into account through the synergistic effect of moderate acid treatment, raw material position setting and roasting in the reducing atmosphere, and good morphology and relatively high purity of the nano silicon carbide crystal whiskers are ensured.

The invention discloses an energy system and method for coupling calcium-based thermochemical heat storage and carbon capture. The energy system comprises a calcination unit, a carbon dioxide pretreatment storage unit, a calcium oxide heat exchange storage unit, a carbonation reaction unit and a heat utilization unit which are arranged based on a boiler. The calcining unit takes green valley electricity as energy to drive calcining reaction to realize heat storage, and generated CaO is processed by the calcium oxide heat exchange storage unit and then is stored for use in a heat release stage; generated COs are stored for standby application after passing through the carbon dioxide pretreatment storage unit; in the heat release stage, CaO and the desulfurized flue gas are subjected to heat release carbonation reaction in the carbonation reaction unit, and heat is released; caCO3 generated by the carbonation reaction can be used for the next heat storage stage; and the heat released by the carbonation reaction is conveyed to the heat utilization unit for heat exchange. Through coupling of calcium-based thermochemical heat storage and carbon capture, green electricity and off-peak electricity are fully utilized, and efficient storage and gradient utilization of energy are achieved.

The invention belongs to the field of functional nano materials, and relates to a method for large-scale preparation of monoclinic phase vanadium dioxide nano powder, a heat insulation film and application of the heat insulation film, and large-scale preparation of the monoclinic phase vanadium dioxide nano powder is successfully achieved by combining a coprecipitation method with low-temperature calcination. The obtained product has excellent size uniformity (the average particle size is 65 + / -10 nm) and an adjustable phase change characteristic (61-68 DEG C). The polymer-based composite film prepared based on the nano powder shows excellent optical performance, and the method has the advantages of mild reaction conditions (less than or equal to 600 DEG C), controllable product morphology and phase transition temperature and the like, and provides a reliable solution for industrial production of nano functional materials for intelligent windows.

The invention discloses a preparation method of a hydrofining catalyst for petrochemical engineering. The preparation method comprises the following steps: step a, carrier pretreatment: putting an aluminum oxide precursor into a dilute nitric acid solution with the mass fraction of 1-5%, dipping for 2-4 hours, and drying at 120-150 DEG C for 3-6 hours; the comprehensive performance of the catalyst is remarkably improved by modifying the alumina carrier with phosphoric acid and optimizing an active component loading process; a gradient acid center is constructed on the surface of the carrier through phosphoric acid treatment to promote adsorption and dissociation of the sulfur / nitrogen-containing compound; the dispersion degree of the active phase is enhanced and high-temperature sintering is inhibited by a bimetal synergistic loading strategy; the pore structure evolution is effectively controlled by a segmented drying and stepped heating roasting process, a through type mesoporous network is formed, and the macromolecular diffusion efficiency is improved; the obtained catalyst is improved in activity in diesel oil hydrodesulfurization, improved in mechanical strength and prolonged in service life.

The invention discloses a preparation method and application of a high-valence nickel monatomic catalyst, through the synergistic effect of nickel-phenanthroline complexing and inert template anchoring, dense and stable anchoring sites are provided for nickel atoms, atom migration and agglomeration in the high-temperature pyrolysis process are effectively inhibited, and the high-valence nickel monatomic catalyst is prepared. Meanwhile, by combining with an air-inert atmosphere two-step calcination procedure, air pre-oxidation is carried out, and a nickel precursor is stabilized in a carrier framework to prevent the nickel precursor from being reduced into a metal state in subsequent high-temperature inert calcination, so that the nickel precursor is locked in an electron-deficient high valence state, and a nickel-loaded material with the nickel loading capacity of 2.9-9.2 wt% and the nickel loading capacity of 9.2-9.2 wt% is prepared. And the nickel element stably exists mainly in the form of Ni < 3 + > or a higher-valence monatomic form, so that the three-in-one breakthrough of high load, high valence and high stability is realized. When the obtained catalyst activates persulfate, high-valence metal oxygen species are preferentially generated, various new pollutants are degraded, and the catalyst has high activity, selectivity and high stability.

The invention belongs to the technical field of catalysts, and discloses an ammonia decomposition hydrogen production catalyst and a preparation method and application thereof. The preparation method of the catalyst for hydrogen production through ammonia decomposition comprises the following steps: in an inert atmosphere, successively carrying out calcination and acid treatment on a carbon carrier to prepare an acid-treated graphitized carbon carrier; adding a ruthenium precursor, a rare earth element precursor and an alkali metal precursor into ethanol, and mixing to prepare a mixed solution; then adding a graphitized carbon carrier into the mixed solution, and mixing; then adding urea and a surfactant, continuously mixing, and standing to obtain a solid precipitate; and finally, carrying out heat treatment on the solid precipitate in a reducing atmosphere. The catalyst takes a highly graphitized carbon material as a carrier, an alkali metal is doped to provide an alkaline environment, and a rare earth metal oxide and Ru form dual-assistant synergistic regulation of an interface, so that low-temperature high-activity ammonia decomposition hydrogen production and long-acting stable operation are realized.

The invention discloses a coal gangue distributed homogeneous high-temperature activation calcination method and system, and relates to the technical field of resources and environments, the system comprises a coal gangue powder preparation and feeding system, a coal gangue powder distributed homogeneous high-temperature activation calcination system, a high-temperature powder cooling system, a finished product collection system and a flue gas purification system; the coal gangue powder distributed homogeneous high-temperature activation calcining system comprises a primary cyclone preheating system and a distributed homogeneous high-temperature activation furnace; the air inlet end of the primary cyclone preheating system is communicated with the coal gangue powder preparing and feeding system, the primary cyclone preheating system is communicated with the homogeneous high-temperature activation furnace, materials in the distributed homogeneous high-temperature activation furnace are separated by the gas-solid cyclone separator and then are divided into two parts by the distributor, one part enters the high-temperature powder cooling system, and the other part enters the high-temperature powder cooling system; and the other part returns to the distributed homogeneous high-temperature activation furnace for circulation. According to the method, large-scale treatment of high-temperature activation and calcination of the coal gangue is realized, and the uniformity and controllability of product quality are remarkably improved.

This invention discloses a method for preparing high-purity zirconium oxide, belonging to the field of compound preparation technology. The method provides a breakthrough adjustment of the final concentration state and the cooling process after concentration and evaporation of an acidic zirconium oxychloride solution under the action of an oxidant. Simultaneously, crystallization is achieved through a two-stage concentration and evaporation process, followed by calcination to obtain hafnium-free zirconium oxide. The resulting zirconium oxide not only has a high yield but also high purity. Furthermore, the technical solution of this invention avoids the generation of ammonia nitrogen wastewater as in existing technologies, thus not only avoiding environmental impact but also significantly reducing production costs through the recycling of hydrochloric acid condensation, achieving a green and environmentally friendly effect.

The invention provides a process for preparing high-purity lithium sulfide based on industrial waste salt recycling, which comprises the following steps: S1, mixing sulfur-containing waste salt and a waste carbon material, granulating, reducing, calcining, separating and purifying to obtain solid sodium sulfide; s2, mixing and ball-milling the obtained solid sodium sulfide and lithium chloride, adding a mixture of a catalyst and ethanol, and performing catalytic reaction to obtain a lithium sulfide crude product; and S3, purifying and drying the obtained lithium sulfide crude product to obtain the lithium sulfide. The method not only can break through the bottleneck of the existing production route, but also can realize the strategic direction of high-value utilization of bulk solid wastes, and has far-reaching significance for promoting sustainable development and green transformation of the battery industry.

The invention provides a modified ferric sodium phosphate pyrophosphate positive electrode material and a preparation method and application thereof.According to the preparation method, mature sanding, spray drying and calcining processes are adopted, and the ferric sodium phosphate pyrophosphate / carbon positive electrode material with a porous spherical structure and high phase purity is prepared by optimizing the combination of raw materials; and the performance breakthrough of high specific capacity, super-large rate capability and excellent super-large rate cycle performance is realized. The provided preparation method is simple and convenient in technological process, high in controllability and suitable for industrialization, the selected raw materials are wide in source and low in cost, the energy consumption in the technological process is relatively low, and the comprehensive production cost has remarkable advantages; the synthesized ferric sodium pyrophosphate / carbon positive electrode material obtains excellent dynamic performance, electrochemical performance and structural stability at an ultra-large rate at 20 DEG C based on special morphology characteristics and relatively high phase purity.

The invention discloses a preparation method and application of a rare earth element doped ruthenium oxide catalyst, and the preparation method comprises the following steps: (1) dissolving a rare earth metal salt, a ruthenium metal salt, dopamine hydrochloride and a Tris-HCl buffer agent in water to obtain a mixed solution, and carrying out in-situ polymerization reaction, solid-liquid separation and drying to obtain a powder precursor; and (2) carrying out high-temperature calcination on the powder precursor obtained in the step (1) to obtain the rare earth doped ruthenium oxide catalyst. Rare earth metal salt and ruthenium salt precursors are dispersed on an in-situ constructed porous carbon substrate, and the rare earth element doped ruthenium oxide nanosheet is generated by oxidation under a high-temperature condition through a self-sacrifice template method. The method has the characteristics of high efficiency and no pollution. The rare earth element doped ruthenium oxide disclosed by the invention is used as a catalyst for the anodic reaction of the acidic electrolyzed water, and shows excellent catalytic activity and wide application prospect.

The invention belongs to the related field of ultra-precision polishing technology, and discloses an ultrasound-piezoelectricity-photocatalysis assisted chemical mechanical polishing method which comprises the following steps: mixing a basic polishing abrasive, a piezoelectric material and a photocatalyst, calcining and grinding, and processing to obtain a modified abrasive; preparing a polishing solution containing a piezoelectric catalysis carrier and a photocatalysis carrier at the same time; the polishing process is completed through a chain of mechanical stress, a piezoelectric electric field, efficient carrier separation and more active species participating in reaction. The invention further discloses a matched polishing device. Compared with the prior art, the method has the advantages that the material removal rate can be effectively increased, the polishing time can be effectively shortened, the surface quality can be further improved, the subsurface damage can be reduced, in addition, a more environment-friendly polishing solution can be used, the waste liquid treatment cost is reduced, the environment is protected, and the method is suitable for industrial production. Therefore, the polishing device is especially suitable for various high-hardness materials to realize the polishing application occasions of low-damage and ultra-smooth surfaces of the high-hardness materials.

The invention relates to the technical field of lime manufacturing, and provides a process and a system for manufacturing high-purity lime. The process comprises the steps of raw material pretreatment, plasma surface pretreatment, segmented atmosphere calcination, sound wave reinforced mass transfer, heat energy comprehensive utilization and intelligent control, rapid cooling, flue gas treatment and finished product packaging. The system comprises a raw material pretreatment unit, a plasma surface pretreatment unit, a multi-section gradient atmosphere calcining kiln, a sound wave reinforced mass transfer system, a heat energy comprehensive utilization and intelligent control system, a carbon dioxide capturing and recycling unit and a finished product cooling and packaging unit. Through raw material deep purification, surface activation treatment, gradient calcination and atmosphere accurate control, sound wave mass transfer reinforcement, intelligent optimization regulation and control, rapid cooling and flue gas purification and resource recovery, the purity and the reaction activity of a calcium oxide product are synergistically improved, and the production energy consumption and pollutant emission are remarkably reduced; and high-efficiency, clean and resource production of the high-purity lime is realized.

The application discloses a preformed methane reforming catalyst and a preparation method thereof. The catalyst comprises a nickel-active alumina first functional component, a cerium oxide nanocluster second functional component and an alumina inert phase. The preparation method comprises preforming an inert phase pretreatment, hydrothermal treatment, calcination and reduction. The preformed inert phase after pretreatment is used as a carrier, which greatly improves the catalyst strength, pertinently weakens the metal-carrier interaction, avoids bed layer temperature drop and carbon deposition caused by local high strength reaction, and improves the operation stability. The first functional component with a layered structure and the second functional component rich in oxygen vacancies further improve the catalyst activity and stability, and the performance indicators are overall superior to those of the existing catalyst products. The preparation method is simple and easy to implement, has no special requirements on equipment, and is conducive to the popularization and application in the fields of methane steam reforming and methane dry reforming.

The invention discloses geopolymer cement based on coal gangue activation reaction as well as a preparation method and application thereof, and relates to the technical field of building materials. The invention relates to a coal gangue concrete, which is prepared from the following raw materials in percentage by mass: 50 to 70 percent of activated coal gangue powder, 5 to 15 percent of alkali activator, 10 to 30 percent of auxiliary cementing material and water, wherein the water accounts for 30 to 40 percent of the total mass of the activated coal gangue powder, the alkali activator and the auxiliary cementing material. Through a composite activation process of medium-temperature calcination decarburization and superfine grinding, the activity of silicon-aluminum components in the coal gangue is effectively excited, the reaction efficiency is remarkably improved, the mixing amount of the coal gangue reaches 50%-70%, the resource utilization rate of solid waste is greatly increased, and efficient activation and resource utilization of the coal gangue are achieved. By adopting the methyl sodium silicate and sodium silicate composite activator, the reaction rate and the product structure are regulated and controlled, and the workability and the setting and hardening behaviors of slurry are improved, so that the obtained geopolymer cement has relatively high early and later strength and excellent durability.

The invention relates to the technical field of gelling materials, in particular to a gelling material based on high-doping-amount shield muck and a preparation method and application thereof.The preparation method comprises the following steps that after original shield muck is sequentially subjected to mechanical crushing, forced homogenization and drying to constant weight, gradient heating calcination is conducted, then rapid cooling is conducted immediately, and the high-doping-amount shield muck is obtained; carrying out two-stage ball milling and sieving to obtain active shield muck powder; preparing a solid dry blend; preparing a composite alkali activator solution; and mixing the composite alkali activator solution with the solid dry blend, primarily stirring and infiltrating, adding the residual mixing water, stirring to obtain uniform geopolymer slurry, and compacting and molding to obtain the cementing material. The problems that in the prior art, a high-performance geopolymer cementing material based on shield muck is low in activity, insufficient in strength, small in shield muck mixing amount, single in performance and poor in volume stability are solved.

The invention relates to the field of preparation of concrete materials, and particularly discloses a high-matching-degree concrete shrinkage compensation additive and application thereof. The additive comprises the following components in parts by weight: 3-20 parts of aluminoferrite mineral powder and 6-26 parts of a modified regulating agent. Wherein the preparation of the modified regulating agent comprises the following steps: (1) mixing a composite modifier composed of dihydrate gypsum powder, a regulating agent and sulfate, calcining in stages, and quenching after the calcination is completed, so as to obtain the beta-type modified semi-hydrated gypsum. And (2) uniformly mixing the beta-type modified semi-hydrated gypsum with anhydrous gypsum powder, then uniformly mixing the obtained mixed powder with liquid polyethylene glycol, standing and aging to obtain the modified regulating agent. According to the high-matching-degree concrete shrinkage compensation additive, expansion can be precisely regulated and controlled in stages, and the adopted industrial solid waste serves as the raw material, so that the cost is reduced, and resource utilization is achieved.

The invention relates to the technical field of battery material recovery, and particularly discloses a method for efficiently recovering lithium and ferrous sulfate heptahydrate in retired lithium iron phosphate through total leaching and green impurity removal. Comprising the following steps: 1, adding strong base and a carbon source into black powder, and calcining at high temperature in an inert atmosphere; step 2, dissolving in pure water after calcining, and carrying out suction filtration to obtain a lithium salt solution and ferrous hydroxide; 3, sulfuric acid is added into ferrous hydroxide for suction filtration, and graphite and a ferric salt solution are obtained; drying the ferric salt solution to obtain ferrous sulfate heptahydrate; step 4, adding alkali into the lithium salt solution to obtain a purified lithium salt solution; 5, introducing carbon dioxide into the purified lithium salt solution, and adding alkali to generate lithium carbonate precipitate; and 6, finally carrying out heat preservation, suction filtration, washing and drying to obtain a lithium carbonate finished product. The technical problems that in the prior art, a traditional decommissioned lithium iron phosphate battery grading recycling technology is complex in production process, more waste liquid pollution is generated, and the production cost is relatively high are solved.