A kind of conbustion synthesis aerosol method prepares novel porous powder in conjunction with phase separation method
Method
Technical field
The present invention relates to a kind of preparation methods of novel porous powder.
Background technique
Porous ceramic film material is that a kind of inside has the inorganic non-metallic material for being largely mutually communicated or being closed hole, is had
Permeability is good, density is low, hardness is high, large specific surface area, thermal conductivity are small, high temperature resistant, the excellent performance such as corrosion-resistant, thus wide
It is applied to the fields such as chemical industry, the energy, metallurgy, environmental protection, medicine, food generally, as filtering, separation, diffusion, heat-insulated, sound absorption, changes
The element materials such as work filler, bioceramic, chemical sensor, catalyst and catalyst carrier also act as fire proofing material, electrolysis
Liquid partition etc..In occasions such as heat-insulated, high temperature, abrasion, corrosion, due to the build-in attribute of ceramic material, porous ceramics is with respect to other
For porous material, there is greater advantage.
The method overwhelming majority for preparing porous material at present all relies on the auxiliary of template (widely used preparation is more
The template Polymeric sponge methods of hole ceramics, addition pore creating material method, extrusion moulding etc.), template is directed to the system of template
Standby, assembling and removal, preparation process is complicated, and energy consumption is high, and the period is long, and environmental pollution is larger.Conventional mould method is to several factors
Sensitivity needs to consider target material to structure collapse is avoided in effective infiltration of template and template removal processes, this causes to prepare
Requirement of the process to operating environment is very harsh, further increases preparation cost.Therefore, develop it is some it is simple, without template, fast
The method that speed, low cost prepare porous material has highly important scientific meaning and practical application value.
Summary of the invention
The present invention is to solve the existing preparation method period is long, energy consumption is high, at high cost, can only small lot production the problem of,
A kind of method that conbustion synthesis aerosol method prepares novel porous powder in conjunction with phase separation method is provided.
The method that conbustion synthesis aerosol method of the present invention prepares novel porous powder in conjunction with phase separation method, it is characterised in that should
Method includes the following steps:
It is uniformly mixed after raw material is dried respectively, is sieved, is fitted into high-pressure reactor, under reaction atmosphere, ignites
Raw material carries out high-temp combustion synthetic reaction, and high-temperature fusant is obtained after fully reacting, after keeping the temperature 1~60s, opens high-pressure reactor
Nozzle, in high-pressure reactor under high pressure gas effect, melt high flow rate sprays, and by air quenching, it is compound micro- to obtain eutectic
Powder;Selective etch is carried out to powder using acid, alkali or organic solution, obtains voluminous powder;The raw material is active metal, oxygen
Agent and inert additwe;The oxidant is the mixing of one or both of nitrate and oxygen, when selection nitrate is made
For oxidant, when reaction atmosphere is air, the mass ratio of active metal and nitrate is 1:(0.20~1), active metal with it is lazy
Property additive mass ratio be 1:(0.20~6);When selecting oxygen as oxidant, reaction atmosphere is oxygen, the oxygen
Pressure be 5~50MPa, the mass ratio of active metal and inert additwe is 1:(1~7);When selection nitrate and oxygen are made
For oxidant, reaction atmosphere is oxygen, and the pressure of the oxygen is 5~50MPa, and the mass ratio of active metal and nitrate is 1:
X, wherein 0<x<1, the mass ratio of active metal and inert additwe is 1:Y, wherein 0.2<y<7.
Further, the active metal powder is one or more of aluminium powder, iron powder, magnesium powder, yttrium powder, chromium powder composition
Mixture.
Further, the nitrate is one or more of aluminum nitrate, ferric nitrate, magnesium nitrate, zirconium nitrate, yttrium nitrate
The mixture of composition.
Further, the inert additwe is aluminium oxide, magnesia, zinc oxide, chromium oxide, zirconium oxide, iron oxide, oxygen
Change the mixture of one or more of yttrium composition.
Further, the system selection principle of the raw material:Reaction product is eutectic system, and eutectic system is mutually to separate
System, the eutectic system be binary eutectic system, ternary eutectic system or multi-element eutectic system;Such as Al2O3-MgO(MgO/
MgAl2O4), Al2O3-ZnO(ZnO/ZnAl2O4), Cr2O3-ZrO2(Cr2O3/ZrO2), Fe2O3-ZrO2(Fe2O3/ZrO2), MgO-
ZrO2(MgO/ZrO2), ZrO2-Y2O3(Y2O3/ZrO2), MgO-Al2O3-ZrO2、MgO-Cr2O3-ZrO2Deng.
The high-pressure reaction vessel include including reactor 1, tabletting 4, nozzle 5, nozzle holder 6, sealing preload piece 8, on
Slide plate 10, lower skateboard 11 and actuator 9, the device bottom thickness direction along reactor 1 are provided with two-stage ladder circular hole, the first ladder circle
The diameter that hole 2 is located at the top of the second ladder circular hole 3 and the first ladder circular hole 2 is greater than the diameter of the second ladder circular hole 3;
The nozzle holder 6 forms coaxial integral structure by circular plate type frame body portion 6-1 and cylindrical portion 6-2, along nozzle branch
The central axes of frame 6 are provided with jack 6-3, and the end face of cylindrical portion 6-2 is provided with ring groove 6-4, and nozzle holder 6 inserts insertion two-stage ladder
In circular hole, cylindrical portion 6-2 and the second ladder circular hole 3 cooperate, and circular plate type frame body portion 6-1 and the first ladder circular hole 2 cooperate, circular plate type
The lower surface of frame body portion 6-1 is overlapped on the step surface of two-stage ladder circular hole, and ring groove 6-4 is embedded with sealing preload piece 8;Spray
The lower surface of the circular plate type frame body portion 6-1 of mouth bracket 6 is provided with seal groove, and the first sealing ring 7 is provided in seal groove;
The upper surface of circular plate type frame body portion 6-1 is arranged in the tabletting 4, and tabletting 4 and 2 screw thread of the first ladder circular hole connect
It connects, the center of tabletting 4 is provided with tabletting through-hole;
Nozzle 5 is arranged in the tabletting through-hole of tabletting 4 and the jack 14 of nozzle holder 6, and it is pre- that the bottom surface of nozzle 5 is against sealing
The upper surface of tight part 8, the upper face of upper slide 10 are in contact with the device bottom outer surface of reactor 1, and the contact setting of lower skateboard 11 exists
Slide plate through-hole is had on the lower section of upper slide 10, upper slide 10 and lower skateboard 11, the aperture of slide plate through-hole guarantees that sealing is pre-
Tight part 8 passes through, and the slide plate through-hole face on lower skateboard 11 seals preload piece 8, and upper slide 10 drives horizontal shifting by actuator 9
It is dynamic;Hydraulic cylinder is connected by pressure converter 12 with upper slide 10.
Raw material is packed into reactor by the present invention, and exothermic reaction sharply occurs after igniting for material system, generates a height
Warm environment reaches all raw material fusing points or more, forms melt.Reactor is closed, because the reasons such as gas expansion exist under high temperature action
Hyperbaric environment is formed in reactor, melt by certain soaking time, is sprayed from spout, formed under hyperbaric environment effect
Powder.
Porous MgAl is prepared in the process of the present invention2O4It is former when selecting metal nitrate as oxidant for powder
It manages as follows:
Conbustion synthesis aerosol method prepares MgO/MgAl2O4Eutectic powder part, with the nitric acid of the aluminium of high reproducibility and high oxidative
Aluminium is as reactant, and using magnesia and aluminium oxide as diluent, reactional equation is:
10Al+2Al(NO3)3→6Al2O3+3N2↑ (1)
Al2O3+MgO→MgAl2O4 (2)
2Al+N2→2AlN (3)
On the one hand the high pressure generated in reaction derives from the expansion of air at high temperature in powder hole, on the other hand come
The nitrogen for decomposing the gas generated and reaction (1) generation derived from aluminum nitrate does not have enough time reacting.It is general to pass through adjusting reaction temperature
Or adjust the content of metal powder and oxidant to adjust reaction pressure, the needs that consideration and melt for reaction safety spray,
Pressure general control is between 3~30MPa.
Then, with the hydrochloric acid of 1mol/L to the MgO/MgAl of preparation2O4Composite ceramic powders carry out pickling, and MgO is dissolved in hydrochloric acid
And MgAl2O4It is insoluble, it removes MgO and forms hole.Distribution of the MgO in powder determines the form of hole.
As selection O2When as oxidant, the principle is as follows:
Aluminothermy conbustion synthesis prepares MgO/MgAl2O4Eutectic powder part, with the aluminium and O of high reproducibility2As reactant, with
As diluent, reactional equation is for magnesia and aluminium oxide:
4Al+3O2→2Al2O3 (4)
Al2O3+MgO→MgAl2O4 (5)
Then etching principle, process are same as described above.
As selection metal nitrate and O2When being used as oxidant simultaneously, aforementioned two kinds of reaction principles are existed simultaneously.Metal powder
Preferentially reacted with oxygen.
Beneficial effects of the present invention:
The method of the present invention, using active metal as reducing agent, as oxidant, two-phase occurs high for metal nitrate or oxygen
Exothermic reaction provides heat source, and the various oxygen not reacted with reactant such as aluminium oxide, zirconium oxide, magnesia, zirconium oxide are added
Compound controls reaction temperature and ingredient as diluent, can prepare grain diameter between 0.5~30 μm, in regular spherical, hole
Diameter submicron order voluminous powder, gained voluminous powder can be used as preparation have hierarchical porous structure porous ceramics matrix
Material.
First raw material is packed into reaction vessel after mixing, ignited, the highly exothermic conbustion synthesis of fast and stable occurs
Reaction, makes temperature reach the fusing point of system or more, and control nozzle arrangements make melt keep the temperature the regular hour, make ingredient in liquid phase shape
State uniformly mixes, and the product of melting is spurted into fast quickly cooling in air by the high pressure then generated in closed container using reaction
But, eutectic powder is formed.Selective etch is carried out to powder using (heat or room temperature) acid, alkali or organic solution later, is obtained more
Hole powder.Reaction process is fast (in the several seconds to reaction can be completed between a few minutes), and ultrahigh in efficiency, quality of dusting every time is at several kilograms
Between to tens kilograms (1~30 kilogram).The preparation efficiency of powder is very high, can be produced in enormous quantities.
The present invention prepares eutectic powder using conbustion synthesis aerosol method, carries out selective etch with acid, alkali or organic solution
The solvable phase (mutually separating) in eutectic structure is removed, to form sequential holes, is prepared into voluminous powder.This method is without outside
Heat source, the heat released when by raw material autoreactivity carry out the technology of inorganic refractory synthesis.In the present invention, system is sent out
Raw exothermic reaction, generates a high temperature and high pressure environment, and temperature is made to reach raw material fusing point or more, forms melt.Melt is in high compression ring
Under the effect of border, is sprayed from spout, form metastable composite granule by air quenching.Whole process belongs to quick far from equilibrium state
Process of setting.By changing technological parameter, eutectic powder, solid solution powder can be prepared.Equipment is simple, short preparation period, former
Expect low, energy-efficient, environmentally protective, the achievable industrialized production of price, there is extensive adaptability.
Detailed description of the invention
Fig. 1 is the structural schematic diagram of high-pressure reactor used in the method for the present invention;
Fig. 2 is the structural schematic diagram of nozzle holder in high-pressure reactor used in the method for the present invention;
Fig. 3 for 1 reference of embodiment MgO-Al2O3Phasor;
Fig. 4 is the exterior appearance figure for the eutectic composite micro-powder that 1 step 4 of embodiment obtains;
Fig. 5 is the porous MgAl that 1 step 5 of embodiment obtains2O4The exterior appearance figure of powder;
Fig. 6 is the porous MgAl that 2 step 4 of embodiment obtains2O4The exterior appearance figure of powder.
Specific embodiment
The technical solution of the present invention is not limited to the following list, further includes between each specific embodiment
Any combination.
Specific embodiment one:Present embodiment conbustion synthesis aerosol method prepares novel porous powder in conjunction with phase separation method
Method, it is characterised in that this method includes the following steps:
It is uniformly mixed after raw material is dried respectively, is sieved, is fitted into high-pressure reactor, under reaction atmosphere, ignites
Raw material carries out high-temp combustion synthetic reaction, and high-temperature fusant is obtained after fully reacting, after keeping the temperature 1~60s, opens high-pressure reactor
Nozzle, in high-pressure reactor under high pressure gas effect, melt high flow rate sprays, and by air quenching, it is compound micro- to obtain eutectic
Powder;Selective etch is carried out to powder using acid, alkali or organic solution, obtains voluminous powder;The raw material is active metal, oxygen
Agent and inert additwe;The oxidant is the mixing of one or both of nitrate and oxygen, when selection nitrate is made
For oxidant, when reaction atmosphere is air, the mass ratio of active metal and nitrate is 1:(0.20~1), active metal with it is lazy
Property additive mass ratio be 1:(0.20~6);When selecting oxygen as oxidant, reaction atmosphere is oxygen, the oxygen
Pressure be 5~50MPa, the mass ratio of active metal and inert additwe is 1:(1~7);When selection nitrate and oxygen are made
For oxidant, reaction atmosphere is oxygen, and the pressure of the oxygen is 5~50MPa, and the mass ratio of active metal and nitrate is 1:
X, wherein 0<x<1, the mass ratio of active metal and inert additwe is 1:Y, wherein 0.2<y<7.
Illustrate present embodiment in conjunction with Fig. 1 and Fig. 2, the high-pressure reaction vessel includes including reactor 1, tabletting 4, nozzle
5, nozzle holder 6, sealing preload piece 8, upper slide 10, lower skateboard 11 and actuator 9, along the device bottom thickness direction of reactor 1
It is provided with two-stage ladder circular hole, the first ladder circular hole 2 is located at the top of the second ladder circular hole 3 and the diameter of the first ladder circular hole 2 is big
In the diameter of the second ladder circular hole 3;
The nozzle holder 6 forms coaxial integral structure by circular plate type frame body portion 6-1 and cylindrical portion 6-2, along nozzle branch
The central axes of frame 6 are provided with jack 6-3, and the end face of cylindrical portion 6-2 is provided with ring groove 6-4, and nozzle holder 6 inserts insertion two-stage ladder
In circular hole, cylindrical portion 6-2 and the second ladder circular hole 3 cooperate, and circular plate type frame body portion 6-1 and the first ladder circular hole 2 cooperate, circular plate type
The lower surface of frame body portion 6-1 is overlapped on the step surface of two-stage ladder circular hole, and ring groove 6-4 is embedded with sealing preload piece 8;Spray
The lower surface of the circular plate type frame body portion 6-1 of mouth bracket 6 is provided with seal groove, and the first sealing ring 7 is provided in seal groove;
The upper surface of circular plate type frame body portion 6-1 is arranged in the tabletting 4, and tabletting 4 and 2 screw thread of the first ladder circular hole connect
It connects, the center of tabletting 4 is provided with tabletting through-hole;
Nozzle 5 is arranged in the tabletting through-hole of tabletting 4 and the jack 14 of nozzle holder 6, and it is pre- that the bottom surface of nozzle 5 is against sealing
The upper surface of tight part 8, the upper face of upper slide 10 are in contact with the device bottom outer surface of reactor 1, and the contact setting of lower skateboard 11 exists
Slide plate through-hole is had on the lower section of upper slide 10, upper slide 10 and lower skateboard 11, the aperture of slide plate through-hole guarantees that sealing is pre-
Tight part 8 passes through, and the slide plate through-hole face on lower skateboard 11 seals preload piece 8, and upper slide 10 drives horizontal shifting by actuator 9
It is dynamic;Hydraulic cylinder is connected by pressure converter 12 with upper slide 10.
In present embodiment on the one hand nitrate and oxygen serve as the effect of oxidant, on the other hand provide suitable pressure
Spray melt from container.
Present embodiment prepares eutectic powder using conbustion synthesis aerosol method, carries out selectivity with acid, alkali or organic solution
Etching removes the solvable phase (mutually separating) in eutectic structure, to form sequential holes, is prepared into voluminous powder.This method is not necessarily to
External heat source, the heat released when by raw material autoreactivity carry out the technology of inorganic refractory synthesis.In the present invention, body
Exothermic reaction occurs for system, generates a high temperature and high pressure environment, and temperature is made to reach raw material fusing point or more, forms melt.Melt is in height
It presses under environmental activity, is sprayed from spout, form metastable composite granule by air quenching.Whole process belongs to far from equilibrium state
Rapid solidification.By changing technological parameter, eutectic powder, solid solution powder can be prepared.Equipment is simple, manufacturing cycle
Short, low, energy-efficient, environmentally protective, the achievable industrialized production of cost of material has extensive adaptability.
Specific embodiment two:The present embodiment is different from the first embodiment in that:The active metal powder is
The mixture of one or more of aluminium powder, iron powder, magnesium powder, yttrium powder, chromium powder composition.It is other same as the specific embodiment one.
Specific embodiment three:The present embodiment is different from the first embodiment in that:The nitrate be aluminum nitrate,
The mixture of one or more of ferric nitrate, magnesium nitrate, zirconium nitrate, yttrium nitrate composition.It is other with one phase of specific embodiment
Together.
Specific embodiment four:The present embodiment is different from the first embodiment in that:The inert additwe is oxygen
Change the mixture of one or more of aluminium, magnesia, zinc oxide, chromium oxide, zirconium oxide, iron oxide, yttrium oxide composition.It is other
It is same as the specific embodiment one.
Specific embodiment five:The present embodiment is different from the first embodiment in that:The system of the raw material selects
Principle:Reaction product is eutectic system, and eutectic system is the system that can be mutually separated, and the eutectic system is binary eutectic
System, ternary eutectic system or multi-element eutectic system.It is other same as the specific embodiment one.
Elaborate below to the embodiment of the present invention, following embodiment under the premise of the technical scheme of the present invention into
Row is implemented, and gives detailed embodiment and specific operating process, but protection scope of the present invention is not limited to following realities
Apply example.
Following embodiment is all made of high-pressure reaction vessel progress, and the high-pressure reaction vessel includes reactor 1, tabletting 4, spray
Mouth 5, nozzle holder 6, sealing preload piece 8, upper slide 10, lower skateboard 11 and actuator 9, along the device base thickness degree side of reactor 1
To two-stage ladder circular hole is provided with, the first ladder circular hole 2 is located at the top of the second ladder circular hole 3 and the diameter of the first ladder circular hole 2
Greater than the diameter of the second ladder circular hole 3;
The nozzle holder 6 forms coaxial integral structure by circular plate type frame body portion 6-1 and cylindrical portion 6-2, along nozzle branch
The central axes of frame 6 are provided with jack 6-3, and the end face of cylindrical portion 6-2 is provided with ring groove 6-4, and nozzle holder 6 inserts insertion two-stage ladder
In circular hole, cylindrical portion 6-2 and the second ladder circular hole 3 cooperate, and circular plate type frame body portion 6-1 and the first ladder circular hole 2 cooperate, circular plate type
The lower surface of frame body portion 6-1 is overlapped on the step surface of two-stage ladder circular hole, and ring groove 6-4 is embedded with sealing preload piece 8;Spray
The lower surface of the circular plate type frame body portion 6-1 of mouth bracket 6 is provided with seal groove, and the first sealing ring 7 is provided in seal groove;
The upper surface of circular plate type frame body portion 6-1 is arranged in the tabletting 4, and tabletting 4 and 2 screw thread of the first ladder circular hole connect
It connects, the center of tabletting 4 is provided with tabletting through-hole;
Nozzle 5 is arranged in the tabletting through-hole of tabletting 4 and the jack 14 of nozzle holder 6, and it is pre- that the bottom surface of nozzle 5 is against sealing
The upper surface of tight part 8, the upper face of upper slide 10 are in contact with the device bottom outer surface of reactor 1, and the contact setting of lower skateboard 11 exists
Slide plate through-hole is had on the lower section of upper slide 10, upper slide 10 and lower skateboard 11, the aperture of slide plate through-hole guarantees that sealing is pre-
Tight part 8 passes through, and the slide plate through-hole face on lower skateboard 11 seals preload piece 8, and upper slide 10 drives horizontal shifting by actuator 9
It is dynamic;Hydraulic cylinder is connected by pressure converter 12 with upper slide 10.
Raw material is packed into reactor, exothermic reaction sharply occurs after igniting for material system, a hot environment is generated,
Reach all raw material fusing points or more, forms melt.Reactor is closed, because the reasons such as gas expansion are in reactor under high temperature action
Hyperbaric environment is formed, melt by certain soaking time, sprays from spout under hyperbaric environment effect, forms powder.This hair
Bright instantaneous opening device is designed to that " gate valve " formula, sealing structure guarantee the sealing under high pressure.By graphite nozzle as heat-insulated material
Material guarantees the structural strength under high temperature, by plate, sprays part, hydraulic cylinder or cylinder as power and executive component, executes ejection
Moment sprays, and in the case where not destroying any device, completes the ejection function of melt liquid under high temperature, high pressure.The device can
The high temperature of 1600~4000 DEG C of tolerance and the high pressure of 5~100MPa.
Beneficial effects of the present invention are verified by following embodiment:
Embodiment 1:
The present embodiment conbustion synthesis aerosol method prepares porous MgAl in conjunction with phase separation method2O4The method of powder, including it is following
Step:
One, by Al (NO3)3·9H2O is placed in vacuum oven and is dried, and drying temperature is 90 DEG C, and drying time is
12h is vacuumized in drying process again every 2h release cleaning steam, after the completion of dry, crossed 40 meshes, obtain aluminum nitrate;
Two, by Al, Al2O3It puts with MgO and dries in a vacuum drying oven, drying temperature is 80 DEG C, drying time 12h;
Three, by the Al (NO of Al, 1270.75g of 1287.75g3)3, 208.55g Al2O3It is mixed with the MgO of 2232.85g
It closes and agate ball is fitted into plastic bottle together, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer, mistake after mixing
Sieve.Wherein temperature sets 3100K;
Four, mixed powder is fitted into high-pressure reaction vessel, under reaction atmosphere, ignite raw material, carries out high-temp combustion conjunction
At reaction, high-temperature fusant is obtained after fully reacting, after keeping the temperature 40s, opens high-pressure reactor nozzle, the high pressure in high-pressure reactor
Under gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Five, obtained powder is subjected to selective etch with hydrochloric acid, the concentration of the hydrochloric acid is 1mol/L, is stirred to react 2h
More than, 80 DEG C of drying temperature after suction filtration obtain porous MgAl2O4Powder.
The reactional equation of the present embodiment is:
10Al+2Al(NO3)3→6Al2O3+3N2↑ (1)
Al2O3+MgO→MgAl2O4 (2)
2Al+N2→2AlN (3)
On the one hand the high pressure generated in reaction derives from the expansion of air at high temperature in powder hole, on the other hand come
The nitrogen for decomposing the gas generated and reaction (1) generation derived from aluminum nitrate does not have enough time reacting.It is general to pass through adjusting reaction temperature
Or adjust the content of metal powder and oxidant to adjust reaction pressure, the needs that consideration and melt for reaction safety spray,
Pressure general control is between 3~30MPa.
Then, with the hydrochloric acid of 1mol/L to the MgO/MgAl of preparation2O4Composite ceramic powders carry out pickling, and MgO is dissolved in hydrochloric acid
And MgAl2O4It is insoluble, it removes MgO and forms hole.Distribution of the MgO in powder determines the form of hole.
Porous MgAl prepared by the present embodiment2O4Powder output is 2960g, shows that average grain diameter is through grain size analysis
6.98μm。
Fig. 3 for the reference of the present embodiment institute MgO-Al2O3Phasor, the corresponding proportion of the present embodiment is Al2O3:MgO=
0.26:0.74, belong to MgO/MgAl2O4Quasi-eutectic region.
Fig. 4 is the exterior appearance figure for the eutectic composite micro-powder that 1 step 4 of embodiment obtains, it can be seen that powder is in regular ball
Shape, and granularity is more uniform.
Embodiment 2:
The present embodiment conbustion synthesis aerosol method prepares porous MgAl in conjunction with phase separation method2O4The method of powder, including it is following
Step:
One, by Al, Al2O3It puts with MgO and dries in a vacuum drying oven, drying temperature is 80 DEG C, drying time 12h;
Two, by the Al of Al, 1618.5g of 963.4g2O3The mixing of MgO powder and agate ball with 2418.1g are packed into together
In plastic bottle, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing.Wherein temperature sets 3100K;
Three, mixed powder is fitted into high-pressure reaction vessel, O is passed through in reaction vessel2, oxygen pressure set 35MPa, draw
Raw material is fired, high-temp combustion synthetic reaction is carried out, high-temperature fusant is obtained after fully reacting, after keeping the temperature 30s, opens high-pressure reactor spray
Mouth, in high-pressure reactor under high pressure gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Four, by obtained powder hydrochloric acid selective etch, the concentration of the hydrochloric acid is 1mol/L, be stirred to react 2h with
On, 80 DEG C of drying temperature after suction filtration obtain porous MgAl2O4Powder.
The present embodiment reactional equation is:
4Al+3O2→2Al2O3 (4)
Al2O3+MgO→MgAl2O4 (5)
Then etching principle, process are same as Example 1.
Porous MgAl prepared by the present embodiment2O4Powder output is 4800g, shows that average grain diameter is through grain size analysis
7.43μm。
Fig. 5 is the porous MgAl that 1 step 5 of embodiment obtains2O4The exterior appearance figure of powder, Fig. 6 are 2 step 4 of embodiment
Obtained porous MgAl2O4The exterior appearance figure of powder.Partial size shown in Fig. 5 is less than normal, and hole gos deep into powder in submicron order, hole
It is interior and relatively uniform;Partial size shown in Fig. 6 is bigger than normal, and hole floats on surface in nanoscale, hole mostly.These results illustrate that burning is closed
It is feasible for preparing voluminous powder in conjunction with phase separation method at aeroponics.
Embodiment 3:
The present embodiment conbustion synthesis aerosol method prepares porous MgAl in conjunction with phase separation method2O4The method of powder, including it is following
Step:
One, by Al (NO3)3·9H2O is placed in vacuum oven and is dried, and drying temperature is 90 DEG C, and drying time is
12h is vacuumized in drying process again every 2h release cleaning steam, after the completion of dry, crossed 40 meshes, obtain aluminum nitrate;
Two, by Al, Al2O3It puts with MgO and dries in a vacuum drying oven, drying temperature is 80 DEG C, drying time 12h;
Three, by the Al (NO of Al, 969.15g of 1101.3g3)3, 770.95g Al2O3It is mixed with the MgO of 2158.6g, and
Agate ball is fitted into plastic bottle together, and ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing;Wherein
Temperature sets 3100K;
Four, mixed powder is fitted into high-pressure reaction vessel, O is passed through in reaction vessel2, oxygen pressure set 10MPa, draw
Raw material is fired, high-temp combustion synthetic reaction is carried out, high-temperature fusant is obtained after fully reacting, after keeping the temperature 40s, opens high-pressure reactor spray
Mouth, in high-pressure reactor under high pressure gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Five, by obtained powder hydrochloric acid selective etch, the concentration of the hydrochloric acid is 1mol/L, be stirred to react 2h with
On, 80 DEG C of drying temperature after suction filtration obtain porous MgAl2O4Powder.
As selection metal nitrate and O2When being used as oxidant simultaneously, aforementioned two kinds of reaction principles are existed simultaneously.Metal powder
Preferentially reacted with oxygen.
Porous MgAl prepared by the present embodiment2O4Powder output is 3650g, shows that average grain diameter is through grain size analysis
9.11μm。
Embodiment 4:
The present embodiment conbustion synthesis aerosol method prepares porous ZnAl in conjunction with phase separation method2O4The method of powder, including it is following
Step:
One, by Al (NO3)3·9H2O is placed in vacuum oven and is dried, and separately the amount of letting off neutrality is dry in vacuum oven
Drying prescription anhydrous magnesium sulfate absorbs steam, and drying time 12h is vacuumized every 2h release cleaning steam again in drying process,
After the completion of drying, 40 meshes are crossed, aluminum nitrate is obtained;
Two, by Al, Al2O3Microwave drying, drying time 4h are carried out under conditions of 40 DEG C with ZnO;
Three, by the Al (NO of Al, 666.25g of 675g3)3、64.15gAl2O3With 3587.8gZnO mixing and agate ball one
It rises and is fitted into plastic bottle, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing;Wherein temperature is set
3200K;
Four, mixed powder is fitted into high-pressure reaction vessel, under reaction atmosphere, ignite raw material, carries out high-temp combustion conjunction
At reaction, high-temperature fusant is obtained after fully reacting, after keeping the temperature 30s, opens high-pressure reactor nozzle, the high pressure in high-pressure reactor
Under gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Five, by obtained powder hydrochloric acid selective etch, the concentration of the hydrochloric acid is 1mol/L, be stirred to react 2h with
On, 80 DEG C of drying temperature after suction filtration obtain porous ZnAl2O4Powder.
Porous ZnAl prepared by the present embodiment2O4Powder output is 1800g, shows that average grain diameter is through grain size analysis
7.58μm。
Embodiment 5:
The present embodiment conbustion synthesis aerosol method prepares porous ZrO in conjunction with phase separation method2The method of powder, including following step
Suddenly:
One, by Zr (NO3)4·5H2O is placed in vacuum oven and is dried, and drying temperature is 80 DEG C, and drying time is
12h after the completion of dry, cross 40 meshes, obtains zirconium nitrate;
Two, by Cr, Cr2O3And ZrO2It is placed in vacuum oven and dries, 80 DEG C of drying temperature, drying time 12h;
Three, by the Zr (NO of Cr, 1232.4g of 2013.7g3)4, 392.65g Cr2O3With the ZrO of 1361.25g2Mixing,
It is fitted into plastic bottle together with agate ball, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing,
Middle temperature sets 3500K;
Four, mixed powder is fitted into high-pressure reaction vessel, under reaction atmosphere, ignite raw material, carries out high-temp combustion conjunction
At reaction, high-temperature fusant is obtained after fully reacting, after keeping the temperature 40s, opens high-pressure reactor nozzle, the high pressure in high-pressure reactor
Under gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Five, powder will be obtained in draught cupboard carries out selective etch, the sulphur-phosphorus nitration mixture with hot sulphur-phosphorus mixed acid solution
Solution ratio is the concentrated sulfuric acid:The volume ratio of concentrated phosphoric acid is 10:7, it is placed on high-temperature electric resistance furnace and is reacted, obtain porous ZrO2Powder
End.
Porous ZrO prepared by the present embodiment2Powder output is 2150g, shows that average grain diameter is 9.11 μ through grain size analysis
m。
Embodiment 6:
The present embodiment conbustion synthesis aerosol method prepares porous ZrO in conjunction with phase separation method2The method of powder, including following step
Suddenly:
One, by Zr (NO3)4·5H2O is placed in vacuum oven and is dried, and drying temperature is 80 DEG C, and drying time is
12h after the completion of dry, cross 40 meshes, obtains zirconium nitrate;
Two, Mg is placed in vacuum oven and is dried, 60 DEG C of drying temperature, drying time 6h;
Three, by MgO and ZrO2It is placed in vacuum oven and dries, 80 DEG C of drying temperature, drying time 12h;
Four, by the zirconium nitrate of Mg, 899.9g of 1032g, the ZrO of the MgO of 30.95g and 3037.15g2And agate ball one
It rises and is fitted into plastic bottle, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing, and wherein temperature is set
3100K;
Five, mixed powder is fitted into high-pressure reaction vessel, under reaction atmosphere, ignite raw material, carries out high-temp combustion conjunction
At reaction, high-temperature fusant is obtained after fully reacting, after keeping the temperature 35s, opens high-pressure reactor nozzle, the high pressure in high-pressure reactor
Under gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Six, powder will be obtained and carry out selective etch with hydrochloric acid, concentration of hydrochloric acid 1mol/L used, be stirred to react time 2h with
On, 80 DEG C of drying temperature after suction filtration obtain porous ZrO2Powder.
Porous ZrO prepared by the present embodiment2Powder output is 3550g, shows that average grain diameter is 9.34 μ through grain size analysis
m。
Embodiment 7:
The present embodiment conbustion synthesis aerosol method prepares porous ZrO in conjunction with phase separation method2The method of powder, including following step
Suddenly:
One, by Zr (NO3)4·5H2O is placed in vacuum oven and is dried, and drying temperature is 80 DEG C, and drying time is
12h after the completion of dry, cross 40 meshes, obtains zirconium nitrate;
Two, by Y, Y2O3And ZrO2Microwave drying, drying time 12h are carried out under conditions of 40 DEG C;
Three, by the zirconium nitrate of Y, 516g of 1441.35g, the Y of 2516.6g2O3With the ZrO of 526.1g2And agate ball is together
It is fitted into plastic bottle, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing, and wherein temperature is set
3500K;
Four, mixed powder is fitted into high-pressure reaction vessel, under reaction atmosphere, ignite raw material, carries out high-temp combustion conjunction
At reaction, high-temperature fusant is obtained after fully reacting, after keeping the temperature 40s, opens high-pressure reactor nozzle, the high pressure in high-pressure reactor
Under gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Five, powder will be obtained and carry out selective etch with the hot hydrochloric acid of 30wt%, be stirred to react time 5h, dry temperature after suction filtration
80 DEG C of degree, obtains porous ZrO2Powder.
Porous ZrO prepared by the present embodiment2Powder output is 1300g, shows that average grain diameter is 7.26 μ through grain size analysis
m。
Embodiment 8:
The present embodiment conbustion synthesis aerosol method prepares porous ZrO in conjunction with phase separation method2The method of powder, including following step
Suddenly:
One, by Zr (NO3)4·5H2O is placed in vacuum oven and is dried, and drying temperature is 80 DEG C, and drying time is
12h after the completion of dry, cross 40 meshes, obtains zirconium nitrate;
Two, by Fe, Fe2O3And ZrO2It is placed in vacuum oven and dries, 80 DEG C of drying temperature, drying time 12h;
Three, by the zirconium nitrate of Fe, 1524.9g of 2675.3g, the Fe of 422.7g2O3With the ZrO of 377.2g2And agate ball
It is fitted into plastic bottle together, ball material mass ratio is 3:1, the mechanical mixture 4.5h on batch mixer are sieved after mixing, and wherein temperature is set
Determine 3100K;
Four, mixed powder is fitted into high-pressure reaction vessel, under reaction atmosphere, ignite raw material, carries out high-temp combustion conjunction
At reaction, high-temperature fusant is obtained after fully reacting, after keeping the temperature 40s, opens high-pressure reactor nozzle, the high pressure in high-pressure reactor
Under gas effect, melt high flow rate sprays, and by air quenching, obtains eutectic composite micro-powder;
Five, concentration of hydrochloric acid 1mol/L used is stirred to react time 2h or more, and 80 DEG C of drying temperature after suction filtration obtain porous
ZrO2Powder.
Porous ZrO prepared by the present embodiment2Powder output is 1200g, shows that average grain diameter is 6.99 μ through grain size analysis
m。