743results about How to "Calcination temperature is low" patented technology

A method for preparing nanometer gahnite. The preparation method is as below: dissolving zinc salt in water, adding an aluminum source, stirring for 10-30 min, adding a pore-enlarging agent, stirring, ageing at 20-100 DEG C for 30-60 min, drying, and calcining at 500-1200 DEG C. The molar ratio of the raw materials is as below: Zn:Al:water=1:2:16-35; calculated by the weight of zinc oxide being 100%, the addition amount of the pore-enlarging agent is 0.5-30%; and the pore-enlarging agent is one or more selected from sucrose, glycerol, ammonium carbonate, ammonium hydrogen carbonate, polystyrene latex and polyethylene glycol.

A ceramic anode structure obtainable by a process comprising the steps of: (a) providing a slurry by dispersing a powder of an electronically conductive phase and by adding a binder to the dispersion, in which said powder is selected from the group consisting of niobium-doped strontium titanate, vanadium-doped strontium titanate, tantalum-doped strontium titanate, and mixtures thereof, (b) sintering the slurry of step (a), (c) providing a precursor solution of ceria, said solution containing a solvent and a surfactant, (d) impregnating the resulting sintered structure of step (b) with the precursor solution of step (c), (e) subjecting the resulting structure of step (d) to calcination, and (f) conducting steps (d)-(e) at least once.

The present invention belongs to the field of nano fluorescent material. Lanthanum oxide (or yttrium or gadolinium oxide), ytterbium oxide and erbiom oxide (or thulium or holmium oxide) are first dissolved in acid to prepare solution; complexone and sodium or potassium molybdenate are added into the solution to produce precipitate, which is centrifugally separated and water washed to prepare aqueous gel, aqueous gel or further prepared alcoholic gel is finally cinerated in a high temperature furnace or heated in a hydrothermal reactor to obtain the nano level up converting fluorescent material. The said material has lanthanum molybdenate as matrix and ytterbium molybdenate and erbium molybdenate as dopant. The material thus prepared has small and homogeneous size, average size 50-60 nm and high light glowing strength and may meet the requirement as biological molecular fluorescent mark material.

Belonging to the field of molecular sieve synthesis, the invention relates to a method for preparing a 3A type zeolite molecular sieve. The preparation method of a 3A type zeolite molecular sieve is characterized by comprising the steps of: 1) calcination of kaolin, thus obtaining metakaolin; 2) preparation of a 4A molecular sieve: mixing metakaolin and a NaOH aqueous solution uniformly, thus obtaining a mixture; filtering the mixture, washing the filter cake with distilled water, and conducting filtration again, drying the filter cake from second filtration at a temperature of 90-100DEG C for 2-4h, thus obtaining the 4A molecular sieve; 3) preparation of a 3A type zeolite molecular sieve: reacting the 4A molecular sieve with a KCl solution in a reaction vessel for 3-5h at a temperature of 70-90DEG C, then conducting cooling, washing, and filtering, drying the obtained filter cake at a temperature of 90-100DEG C for 2-4h, thus obtaining the 3A type zeolite molecular sieve. The method of the invention has simple process and low calcination temperature, and the prepared 3A type zeolite molecular sieve has great calcium ion exchange capacity and good performances.

The invention provides a preparation method and use of a Bi2O3/Bi2O4 phase heterojunction photocatalyst. The preparation method comprises the following steps: firstly, mixing 2.8 g of bismuth salt with 0-1.87 g of alkali uniformly to prepare a paste; then, placing a mixture into a muffle furnace and calcining at 100-450 DEG C for 0.5-4.0 h; washing a calcined substance with deionized water; and drying at 60 DEG C to obtain earthy yellow to reddish brown solids which are the Bi2O3/Bi2O4 heterojunction photocatalyst. The Bi2O3/Bi2O4 phase heterojunction photocatalyst prepared in the invention isused for degrading organic pollutants in water, and has higher visible light catalyzing activity than a commercial Bi2O3 photocatalyst.

A process for preparing high-activity lime by vacuum calcining of lime stone includes such steps as crushing lime stone, loading in tank, heating in electric vacuum furnace at 750-900 deg.C under 100-1000 Pa, and quick cooling. Its activity is 380-450 ml.

A process for preparing rutile-type titanium pigment powder by dual-effect crystal seed method includes such steps as preparing dual-effect crystal seeds, hydrolyzing titanium liquid while adding the crystal seeds while plays the role of crystal nucleus of hydrolized metatitanic acid particle, and calcining where it plays the role of the crystal nucleus for rutile-type phase change. Its advantages are low calcining temp, low cost and high output.

The invention discloses belite-sulphoaluminate-ferrous aluminate cement which comprises the following components by mass percent: 38-70% of beta-C2S, 27-37% of C4A3S-(refer to the description) and 3-25% of C4AF. The invention further discloses a preparation method of the belite-sulphoaluminate-ferrous aluminate cement. The preparation method comprises the following steps: with industrial waste residue and industrial gypsum as the raw materials, mixing the raw materials with aluminous corrective addition namely bauxite or tailing bauxite, forming, performing hydrothermal reaction, crushing, calcining and grinding to obtain the belite-sulphoaluminate-ferrous aluminate cement. According to the invention, the low-carbon belite-sulphoaluminate-ferrous aluminate cement is prepared at low temperature; in addition, limestone is not used, so that no carbon dioxide is generated to increase the environmental pressure; moreover, the calcining temperature is low, so that the energy consumption is low, and the preparation method is a low-carbon and environment friendly preparation method.

The invention discloses a production process of building envelope products and belongs to the field of civil engineering. Light calcined magnesia power or mixture of light calcined magnesia power and quicklime is proportionally mixed with mineral admixtures such as granulated blast-furnace slag, coal ash, silica fume, red mud tailing powder and slag to obtain cementing material, the cementing material is mixed with aggregate and water into mixture used for producing building envelope material, and the building envelope material is finally hardened under CO2 environment into building envelope products such as building blocks, plates and tiles by means of mixing, forming, precuring and the like. The production process is low in production energy consumption, CO2 emitted from industrial waste residue and in industrial production is effectively utilized, and the building envelope products are new energy-saving environment-friendly products.

The invention discloses a preparation method of a catalyst for preparing propylene by virtue of propane dehydrogenation. The catalyst comprises an aluminum oxide carrier and active components with the following contents in percentage by mass calculated based on the carrier: 1-3% of calcium silicate salt, 1-3% of cerium oxide, 0.1-2.0% of a platinum group metal, 0.5-5.0% of potassium, 0.2-5.0% of cerium or samarium, 0.3-10% of halogen, 1-5% of a pore forming agent and the balance of impurities, wherein the molar ratio of cerium or samarium to the platinum group metal is 7:8; the platinum group metal is platinum; and halogen is chlorine. The preparation method comprises the following steps: soaking, drying and roasting the aluminum oxide carrier by using a soluble compound solution of cerium or samarium and a calcium silicate salt solution, then soaking, drying and roasting by using a solution containing compounds of the platinum group metal and hydrogen halide, and then soaking, drying and roasting by using a potassium salt solution; and then mixing cerium oxide and the pore forming agent with corresponding amounts, and roasting for 3 hours at 600 DEG C to obtain the catalyst for preparing propylene by virtue of propane dehydrogenation.

The invention provides an alpha/beta-Bi2O3 phase heterojunction photocatalyst as well as a preparation method and application thereof. The method comprises the following steps: firstly dissolving 2-4mmol of a bismuth source material in 70mL of a reductive solvent, magnetically stirring for 30 minutes under the room temperature, then adding 0-2.0mL of aniline into the solution, and continuing to stir for 10 minutes; transferring the mixed solution into a reactor, putting the mixed solution in a drying oven for carrying out solvothermal reaction for 8-12 hours at the temperature of 150-180 DEG C to obtain a bismuth-based precursor; washing, drying and grinding the precursor, putting the precursor in a muffle furnace for calcining for 0.5-2.0 hours at the temperature of 300 DEG C to obtain yellowish green powder which is the alpha/beta-Bi2O3 phase heterojunction photocatalyst. The prepared alpha/beta-Bi2O3 phase heterojunction photocatalyst is used for degrading organic pollutants in water; compared with commercial TiO2 (P25), pure-phase alpha-Bi2O3 and pure-phase beta-Bi2O3 photocatalysts, the alpha/beta-bismuth oxide phase heterojunction photocatalyst has higher visible-light catalytic activity.

A process for extracting aluminum hydroxide (or oxide) from coal gangue and using the residual dregs to prepare cement includes such steps as calcining coal gangue, mixing with lime or calcium carbide dregs and water, steam pressure reaction to generate the resultant containing hydrated calcium silicoaluminate and calcium hydroxide, calcining to obtain the dodecylcalcium hepatoaluminate and dicalcium silicate, extracting in sodium carbonate solution, adding lime for desiliconizing, carbonizing to obtain aluminum oxide, calcining to obtain aluminum oxide, and using the SiCa dregs to prepare cement.

The invention relates to a preparation method of Eu-doping calcium titanate CaTiO3:Eu<3+> fluorescent powders, which comprises the steps as follows: a soluble europium salt, a calcium salt and Ti(OC4H9)4 are weighed according to the mole ratio that is 1:49:50 to 1:4:5 among Eu<3plus>, Ca<2plus> and Ti<4plus>, and are respectively dissolved in absolute ethyl alcohol, and the confected solution is stirred for ample dissolution; (2) a mixed ethanol solution of the europium salt and the calcium salt is added in an ethanol solution of Ti(OC4H9)4, and a sol is obtained through stirring; (3) the sol is placed at the temperature ranging from 0 to 50 DEG C to obtain a wet gel which is put in a baking box for drying; (4) the dried gel is milled into powders, the obtained powders are calcined for 2 to 8 hours to obtain the CaTiO3:Eu<3plus> fluorescent powders. In the preparation method, the prepared CaTiO3:Eu<3plus> fluorescent powders have high chemical durability, small grain size, pure crystalling phase and low calcination temperature; the preparation method has simple technology, and is easy for industrialized production.

The invention provides a method for growing multi-walled carbon nano tubes on the surface of micron silicon carbide powder in situ. The method comprises the steps of firstly oxidizing, acid-washing and alkali-washing the surface of the silicon carbide powder to remove silicon oxide and other impurities on the surface; secondly wrapping the surface of silicon carbide with a layer of uniformly distributed nano-catalyst particles by adopting the method of chemical codeposition, then putting the powder into a quartz tube furnace, and preparing the carbon nano tubes on the surface of silicon carbide in situ through catalytic cracking by utilizing the method of chemical vapor deposition. By adopting the method, uniform distribution of the carbon nano tubes on the surface of micron silicon carbide can be achieved, the difficulty that the carbon nano tubes are easy to agglomerate is solved, and a basis is provided for preparing high-performance multi-scale composite materials. The method is simple and has high feasibility. The prepared carbon nano tubes are uniformly dispersed on the surface of silicon carbide and are controllable in quantity.

The invention provides a method for preparing target-used Ru powder and relates to the technical field of precious metal powder production. The method for preparing the target-used Ru powder comprises the steps as follows; 1) solvation, 2) precipitation, 3) centrifugal filtration, 4) drying, 5) crushing, 6) calcination, 7) reduction and 8) powder preparation. According to the method, oxidation reaction is performed by means of chlorine gas to oxidize Ru (III) in a solution into Ru (IV), simultaneously, the concentration of Ru is controlled in a range of 45-55 g/L, the concentration of hydrochloric acid is controlled in a range of 8-12 mol/L, the oxidizing temperature is controlled in a range of 90-100 DEG C, and the mixing speed is 60-90 revolutions/min, so that 99.9% of (NH4)2RuCl6(IV) in the solution can be precipitated, the (NH4)2RuCl6(IV) is separated from impurities, and the purity of the (NH4)2RuCl6(IV) is improved.

The invention relates to an ultrathin high-purity ceramic wafer and a preparation process thereof. Ceramic powder of the ceramic wafer is a mixture of micron powder and nanometer powder, and the nanometer powder accounts for 10-30% the volume of the ceramic powder; the median diameter of the micron powder is smaller than or equal to 3.0 microns; the median diameter of the nanometer powder is smaller than or equal to 0.2 micron; the micron powder particles are in contact with one another, and gaps among the micron powder are filled with the nanometer powder; preparation processes of tape casting zone generation and solid phase sintering are adopted, the ceramic powder serves as the solid phase of a sizing agent, and the mass of the ceramic mass accounts for 65% or above of that of the sizing agent; the solid phase sintering temperature is 100 DEG C or above lower than that of the theoretical sintering temperature of the micron powder. According to the ultrathin high-purity ceramic wafer and the preparation process thereof, the mixture of the micron powder and the nanometer powder serves as the ceramic powder, the volume ratio of the micron powder and the nanometer powder is reasonably regulated, and the sintering temperature is lowered without adding a sintering agent; an ultrathin ceramic plate which is flat in surface is prepared through the processes of raising the solid content and raising the sintering temperature, and the ceramic wafer still maintains a high heat-conducting property and does not change the dielectric property.

The invention belongs to the technical field of manufacturing of lithium battery cathode materials, and specifically relates to a method for compositely coating a lithium battery cathode material withtungsten oxide and nitrogen-doped carbon. A coating layer is formed on the surface of the lithium battery positive electrode material by polymerization of a carbon precursor and precipitation of a tungsten precursor. Curing and bonding of coating layer are realized through a calcining process. According to the present invention, the method has characteristics of low cost, low energy consumption and simple operation, and the lithium battery positive electrode material prepared through the method has characteristics of excellent electronic conductivity and excellent electrochemical stability.

The invention relates to road delayed-coagulation cement and a preparation method thereof. The road delayed-coagulation cement comprises special cement clinker, limestone waste, modified steel slag powder and phosphorus gypsum. According to the road delayed-coagulation cement, a cement raw material is prepared from carbon-containing shale, the phosphorus gypsum serves as mineralizing agents of clinker calcination, steel slag powder is prepared in a crushing, iron removing and grinding manner, the steel slag powder and the limestone waste serve as cement admixtures, and the phosphorus gypsum serves as a cement delayed coagulant. By the aid of the technical scheme, the prepared road delayed-coagulation cement has the advantages that coagulation time is suitable, early strength is high, laterstrength is rapidly increased, breaking strength is high, abrasion resistance is good, dry shrinkage performance is low and the like. Efficient resource utilization of solid waste such as the carbon-containing shale, the limestone waste, steel slag and the phosphorus gypsum is achieved, and the road delayed-coagulation cement has important economic benefits and social benefits.

The invention relates to a method for producing cement clinker through utilization of a stainless steel cold-rolled dehydrated sludge ingredient. The method comprises that: stainless steel cold-rolled dehydrated sludge and other materials of a cement green stock are evenly mixed to prepare the cement green stock; the cement green stock comprises the following compositions in percentage by weight: 70 to 79 percent of limestone, 10 to 14 percent of clay, 1 to 8 percent of the stainless steel cold-rolled dehydrated sludge, 5.3 percent of coal ash, 0 to 3 percent of iron ore powder and 0 to 0.5 percent of gypsum; and the prepared cement green stock is sintered to form silicate cement clinker. The obtained cement clinker and a corresponding cement product have no essential difference with the prior silicate cement clinker and a cement product in composition and performance; the quality of the cement clinker and the corresponding cement product meets the index requirement of national corresponding product standard and can be used as a normal high-quality commodity; and the method effectively utilizes and processes industrial sludge containing harmful metal elements, achieves the effects of resource optimization and utilization and has remarkable environment-friendly benefit.