CN108178180B - A kind of preparation method of Large ratio surface cerium oxide - Google Patents
A kind of preparation method of Large ratio surface cerium oxide Download PDFInfo
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- CN108178180B CN108178180B CN201810191198.4A CN201810191198A CN108178180B CN 108178180 B CN108178180 B CN 108178180B CN 201810191198 A CN201810191198 A CN 201810191198A CN 108178180 B CN108178180 B CN 108178180B
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- 229910000420 cerium oxide Inorganic materials 0.000 title claims abstract description 30
- BMMGVYCKOGBVEV-UHFFFAOYSA-N oxo(oxoceriooxy)cerium Chemical compound [Ce]=O.O=[Ce]=O BMMGVYCKOGBVEV-UHFFFAOYSA-N 0.000 title claims abstract description 30
- 238000002360 preparation method Methods 0.000 title claims abstract description 28
- MUBZPKHOEPUJKR-UHFFFAOYSA-N Oxalic acid Chemical compound OC(=O)C(O)=O MUBZPKHOEPUJKR-UHFFFAOYSA-N 0.000 claims abstract description 118
- 235000012501 ammonium carbonate Nutrition 0.000 claims abstract description 59
- VZDYWEUILIUIDF-UHFFFAOYSA-J cerium(4+);disulfate Chemical compound [Ce+4].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O VZDYWEUILIUIDF-UHFFFAOYSA-J 0.000 claims abstract description 48
- 229910000355 cerium(IV) sulfate Inorganic materials 0.000 claims abstract description 48
- 239000007788 liquid Substances 0.000 claims abstract description 48
- 238000006243 chemical reaction Methods 0.000 claims abstract description 37
- 239000000706 filtrate Substances 0.000 claims abstract description 37
- 235000006408 oxalic acid Nutrition 0.000 claims abstract description 37
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 19
- 238000000926 separation method Methods 0.000 claims abstract description 18
- 239000000463 material Substances 0.000 claims abstract description 14
- ATRRKUHOCOJYRX-UHFFFAOYSA-N Ammonium bicarbonate Chemical compound [NH4+].OC([O-])=O ATRRKUHOCOJYRX-UHFFFAOYSA-N 0.000 claims abstract description 13
- 239000001099 ammonium carbonate Substances 0.000 claims abstract description 13
- 238000001816 cooling Methods 0.000 claims abstract description 13
- 238000007873 sieving Methods 0.000 claims abstract description 11
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 claims description 31
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 claims description 24
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 24
- 239000013078 crystal Substances 0.000 claims description 22
- 229910052938 sodium sulfate Inorganic materials 0.000 claims description 18
- 235000011152 sodium sulphate Nutrition 0.000 claims description 18
- UXVMQQNJUSDDNG-UHFFFAOYSA-L Calcium chloride Chemical compound [Cl-].[Cl-].[Ca+2] UXVMQQNJUSDDNG-UHFFFAOYSA-L 0.000 claims description 17
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 claims description 13
- 239000011575 calcium Substances 0.000 claims description 13
- 229910052791 calcium Inorganic materials 0.000 claims description 13
- 238000003756 stirring Methods 0.000 claims description 13
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 12
- 238000001354 calcination Methods 0.000 claims description 12
- 229910000019 calcium carbonate Inorganic materials 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 12
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 12
- ZNCPFRVNHGOPAG-UHFFFAOYSA-L sodium oxalate Chemical compound [Na+].[Na+].[O-]C(=O)C([O-])=O ZNCPFRVNHGOPAG-UHFFFAOYSA-L 0.000 claims description 11
- 229940039790 sodium oxalate Drugs 0.000 claims description 11
- 229940039748 oxalate Drugs 0.000 claims description 7
- -1 sulfate radical Chemical class 0.000 claims description 7
- NLXLAEXVIDQMFP-UHFFFAOYSA-N Ammonia chloride Chemical compound [NH4+].[Cl-] NLXLAEXVIDQMFP-UHFFFAOYSA-N 0.000 claims description 6
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 claims description 6
- 238000001704 evaporation Methods 0.000 claims description 6
- 239000012263 liquid product Substances 0.000 claims description 6
- 238000002156 mixing Methods 0.000 claims description 6
- 239000012452 mother liquor Substances 0.000 claims description 6
- IPGOVDXOBDFUBM-UHFFFAOYSA-N oxalic acid;sodium Chemical compound [Na].OC(=O)C(O)=O IPGOVDXOBDFUBM-UHFFFAOYSA-N 0.000 claims description 6
- 239000007787 solid Substances 0.000 claims description 6
- 238000005406 washing Methods 0.000 claims description 6
- 230000002572 peristaltic effect Effects 0.000 claims description 5
- 244000025254 Cannabis sativa Species 0.000 claims description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 claims 1
- 239000000460 chlorine Substances 0.000 claims 1
- 229910052801 chlorine Inorganic materials 0.000 claims 1
- 239000011734 sodium Substances 0.000 claims 1
- 229910052708 sodium Inorganic materials 0.000 claims 1
- 230000003197 catalytic effect Effects 0.000 abstract description 6
- MWUXSHHQAYIFBG-UHFFFAOYSA-N nitrogen oxide Inorganic materials O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 12
- VBIXEXWLHSRNKB-UHFFFAOYSA-N ammonium oxalate Chemical compound [NH4+].[NH4+].[O-]C(=O)C([O-])=O VBIXEXWLHSRNKB-UHFFFAOYSA-N 0.000 description 11
- 239000003054 catalyst Substances 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 4
- 239000004215 Carbon black (E152) Substances 0.000 description 4
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 4
- 229910002091 carbon monoxide Inorganic materials 0.000 description 4
- 229930195733 hydrocarbon Natural products 0.000 description 4
- 150000002430 hydrocarbons Chemical class 0.000 description 4
- 230000003647 oxidation Effects 0.000 description 4
- 238000007254 oxidation reaction Methods 0.000 description 4
- 230000001376 precipitating effect Effects 0.000 description 4
- 229910052684 Cerium Inorganic materials 0.000 description 3
- GWXLDORMOJMVQZ-UHFFFAOYSA-N cerium Chemical compound [Ce] GWXLDORMOJMVQZ-UHFFFAOYSA-N 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 2
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000005864 Sulphur Substances 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 229910052799 carbon Inorganic materials 0.000 description 2
- 238000005516 engineering process Methods 0.000 description 2
- 230000032683 aging Effects 0.000 description 1
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000001569 carbon dioxide Substances 0.000 description 1
- 229910002092 carbon dioxide Inorganic materials 0.000 description 1
- 238000006555 catalytic reaction Methods 0.000 description 1
- 238000000975 co-precipitation Methods 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000003837 high-temperature calcination Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- 238000005120 petroleum cracking Methods 0.000 description 1
- 239000000843 powder Substances 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000002351 wastewater Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
- C01F17/00—Compounds of rare earth metals
- C01F17/20—Compounds containing only rare earth metals as the metal element
- C01F17/206—Compounds containing only rare earth metals as the metal element oxide or hydroxide being the only anion
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
- B01J23/10—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of rare earths
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/61—Surface area
- B01J35/613—10-100 m2/g
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J35/00—Catalysts, in general, characterised by their form or physical properties
- B01J35/60—Catalysts, in general, characterised by their form or physical properties characterised by their surface properties or porosity
- B01J35/61—Surface area
- B01J35/615—100-500 m2/g
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2004/00—Particle morphology
- C01P2004/60—Particles characterised by their size
- C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/12—Surface area
-
- C—CHEMISTRY; METALLURGY
- C01—INORGANIC CHEMISTRY
- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
- C01P2006/00—Physical properties of inorganic compounds
- C01P2006/80—Compositional purity
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Inorganic Chemistry (AREA)
- Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)
Abstract
The present invention discloses a kind of preparation method of Large ratio surface cerium oxide.With liquid, ceric sulfate, ammonium carbonate, oxalic acid are configured to solution, the oxalic acid solution of preparation is put into reaction kettle, the sal volatile of 0.1-0.12 times of volume of oxalic acid solution is added, then ceric sulfate solution and sal volatile are added in the liquid of bottom, temperature is at the uniform velocity reduced in simultaneous reactions kettle, reaction kettle stops cooling after charging, and this temperature is maintained to be stirred to react 1-1.5h, it is then separated by solid-liquid separation, obtains the first filtrate and the first filter residue, pure water is added in first filter residue, then it dries, is sieved after broken, obtains sieving materials；Sieving materials are calcined in rotary kiln, then by it is broken, sieve to get.Preparation process of the present invention is simple, there is biggish specific surface area at ambient and elevated temperatures, and catalytic activity is high.
Description
Technical field
The present invention relates to a kind of preparation methods of Large ratio surface cerium oxide, belong to catalyst technical field.
Background technique
The cerium oxide of Large ratio surface is applied to petroleum cracking and cracking, the fields such as purifying vehicle exhaust catalysis.Conventional work
Skill is prepared using coprecipitation, by the reunion in control powder preparation process and is added stabilizer, is made product at high temperature
Still keep biggish specific surface area.The purity of the cerium oxide of Large ratio surface on the market is greater than 99.9%, and granularity is 1-3 microns,
Fresh specific surface is to be generally less than 160m2/g, and aging specific surface area (1000 DEG C of 4hr) is less than 25m2/g.
The cerium oxide of general Large ratio surface is used for high-temperature catalytic, and high temperature can make conventional Large ratio surface cerium oxide
Specific surface drastically reduces, to affect catalytic effect.
Summary of the invention
In view of this, preparation process is simple, in room temperature the present invention provides a kind of preparation method of Large ratio surface cerium oxide
With have biggish specific surface area under high temperature, catalytic activity is high.
The present invention solves above-mentioned technical problem by following technological means:
A kind of preparation method of Large ratio surface cerium oxide, is following steps:
(1) match liquid, technical pure ceric sulfate is configured to the ceric sulfate solution that concentration is 180-185g/L, and constant temperature arrives
Temperature is 40 ± 2 DEG C, technical pure ammonium carbonate is configured to the sal volatile that concentration is 550-600g/L, and constant temperature to temperature is
40 ± 2 DEG C, technical pure oxalic acid is configured to the oxalic acid solution that concentration is 100-105g/L, and constant temperature to temperature is 40 ± 2 DEG C；
(2) it reacts, the oxalic acid solution of preparation is put into reaction kettle, and constant temperature to temperature is 40 ± 2 DEG C, in reaction kettle
Cooling coil is set, is then stirred, the ammonium carbonate of 0.1-0.12 times of volume of oxalic acid solution is added in mixing speed 100-120r/min
Solution, addition, which finishes, to be continued to stir 15-30min, and as bottom liquid, ceric sulfate solution and sal volatile are then added to bottom
In liquid, temperature is at the uniform velocity reduced in simultaneous reactions kettle, the rate for reducing temperature is 5-6 DEG C/h, and ceric sulfate solution and ammonium carbonate are molten
The volume flow ratio of liquid is 6-6.2:1, and the ceric sulfate solution and sal volatile total volume for amounting to addition are bottom liquid product
1-1.5 times, the time that ceric sulfate solution and sal volatile is added is 3-4 hours, and reaction kettle stops cooling after charging,
And this temperature is maintained to be stirred to react 1-1.5h, it is then separated by solid-liquid separation, obtains the first filtrate and the first filter residue, by the first filter residue
The conductivity 150-250 μ S/cm of pure water to washing water is added, then dries to moisture content and is lower than 1%, after broken
150-200 mesh is crossed, sieving materials are obtained；
(3) it calcines, step (2) sieving materials is calcined in rotary kiln, calcination temperature is 340-360 DEG C, calcination time 5-6
Hour, then by it is broken, sieve to get.
Ceric sulfate solution, sal volatile and the oxalic acid solution prepared in the step (1) make after secondary filter
With the aperture of filter medium is 0.5-1 microns.
It is at the uniform velocity to be added that bottom liquid process, which is added, with sal volatile in ceric sulfate solution in the step (2), and equipment is added
For at least one of peristaltic pump or metering pump.
Calcium chloride solution is added in first filtrate obtained in the step (2), is stirred to react 1-2 hours, then filters, washes
It washs, condensing crystallizing obtains ammonia chloride crystal after filtrate and wash water are merged, and filter residue is added sodium carbonate liquor and carries out pulp, then again
Temperature is 70-75 DEG C after reaction 1-2 hours, then filters, obtains the filtrate and calcium carbonate filter residue containing sodium sulphate and sodium oxalate,
Containing the filtrate of sodium sulphate and sodium oxalate by being concentrated into Baume degrees as 50-52, being subsequently cooled to temperature is 10-15 DEG C, is carried out
It is separated by solid-liquid separation, obtains the oxalic acid sodium crystal that purity is 98% or more, the mother liquor of separation of solid and liquid will obtain pure after moisture evaporating completely
The sodium sulfate crystal for spending > 97%, obtained calcium carbonate filter residue are added hydrochloric acid solution and obtain calcium chloride solution return use.
The molal quantity of calcium is the total moles of sulfate radical, oxalate and carbonate in the first filtrate in the calcium chloride solution of addition
Several 1.05-1.1 times, the sodium carbonate of addition are 1.05-1.1 times of calcium molal quantity in filter residue.
Present invention utilizes the solubility that the solubility of ammonium oxalate is significantly smaller than oxalic acid, ammonium oxalate is in 40 DEG C of solubility
It is 4.45 that 8.18,30 DEG C, which are 6.09,20 DEG C, and the solubility of oxalic acid is 21.2,30 DEG C in 40 DEG C of solubility and is 14.3,20 DEG C and is
9.5, ammonium carbonate is added in oxalic acid, generation obtains ammonium oxalate, so that ammonium oxalate partially crystallizable is precipitated, ceric sulfate is then added
Solution and sal volatile, then Ce (IV) ion can be using this ammonium oxalate crystal as nucleus growth, to ammonium oxalate be wrapped up, together
When, in continuous reaction process, temperature is gradually decreased, while constantly obtaining Ce (IV) precipitating, also constantly there is oxalic acid
The crystal of ammonium is precipitated, so that Ce (IV) precipitating is mixed with ammonium oxalate crystal, in high-temperature burning process, the grass of package
The ammonium oxalate of sour ammonium and mixed growth can resolve into ammonia, carbon dioxide gas, vapor and vapor away, to obtain hollow knot
The cerium oxide of structure and loose porous Large ratio surface, the cerium oxide hole that the present invention obtains is big, and is hollow structure, at high temperature
Its specific surface area is much larger than existing product on the market, and catalytic performance is superior.
The index of finally obtained Large ratio surface cerium oxide of the invention is as follows:
The beneficial effects of the present invention are:
1. so that Ce (IV) precipitating is wrapped on ammonium oxalate nucleus, while constantly existing by using ammonium oxalate as nucleus
Then reaction process cooling said high-temperature calcination, so that careless so that ammonium oxalate crystal is constantly precipitated with Ce (IV) precipitating together
Sour ammonium decomposes, so that cerium oxide becomes hollow and loose porous structure, and the cerium oxide for other techniques preparation that compares,
Hole is bigger, and what hole was blocked at high temperature lacks, and hollow structure, so that specific surface area at ambient and elevated temperatures is all larger than
Existing cerium oxide, catalytic effect are more preferable.
2. preparation process waste water yield is few, ammonium root therein, oxalate, sulfate radical realize recycling, so that preparation
Environmental friendly property is good.
3. passing through conventional depositing technology and calcine technology, it can it prepares this large surface and accumulates virtue cerium oxide, technique letter
It is single, it is at low cost.
Specific embodiment
Below with reference to specific embodiment, the present invention is described in detail, a kind of Large ratio surface cerium oxide of the present embodiment
Preparation method, be following steps:
(1) match liquid, technical pure ceric sulfate is configured to the ceric sulfate solution that concentration is 180-185g/L, and constant temperature arrives
Temperature is 40 ± 2 DEG C, technical pure ammonium carbonate is configured to the sal volatile that concentration is 550-600g/L, and constant temperature to temperature is
40 ± 2 DEG C, technical pure oxalic acid is configured to the oxalic acid solution that concentration is 100-105g/L, and constant temperature to temperature is 40 ± 2 DEG C；
(2) it reacts, the oxalic acid solution of preparation is put into reaction kettle, and constant temperature to temperature is 40 ± 2 DEG C, in reaction kettle
Cooling coil is set, is then stirred, the ammonium carbonate of 0.1-0.12 times of volume of oxalic acid solution is added in mixing speed 100-120r/min
Solution, addition, which finishes, to be continued to stir 15-30min, and as bottom liquid, ceric sulfate solution and sal volatile are then added to bottom
In liquid, temperature is at the uniform velocity reduced in simultaneous reactions kettle, the rate for reducing temperature is 5-6 DEG C/h, and ceric sulfate solution and ammonium carbonate are molten
The volume flow ratio of liquid is 6-6.2:1, and the ceric sulfate solution and sal volatile total volume for amounting to addition are bottom liquid product
1-1.5 times, the time that ceric sulfate solution and sal volatile is added is 3-4 hours, and reaction kettle stops cooling after charging,
And this temperature is maintained to be stirred to react 1-1.5h, it is then separated by solid-liquid separation, obtains the first filtrate and the first filter residue, by the first filter residue
The conductivity 150-250 μ S/cm of pure water to washing water is added, then dries to moisture content and is lower than 1%, after broken
150-200 mesh is crossed, sieving materials are obtained；
(3) it calcines, step (2) sieving materials is calcined in rotary kiln, calcination temperature is 340-360 DEG C, calcination time 5-6
Hour, then by it is broken, sieve to get.
Ceric sulfate solution, sal volatile and the oxalic acid solution prepared in the step (1) make after secondary filter
With the aperture of filter medium is 0.5-1 microns.
It is at the uniform velocity to be added that bottom liquid process, which is added, with sal volatile in ceric sulfate solution in the step (2), and equipment is added
For at least one of peristaltic pump or metering pump.
Calcium chloride solution is added in first filtrate obtained in the step (2), is stirred to react 1-2 hours, then filters, washes
It washs, condensing crystallizing obtains ammonia chloride crystal after filtrate and wash water are merged, and filter residue is added sodium carbonate liquor and carries out pulp, then again
Temperature is 70-75 DEG C after reaction 1-2 hours, then filters, obtains the filtrate and calcium carbonate filter residue containing sodium sulphate and sodium oxalate,
Containing the filtrate of sodium sulphate and sodium oxalate by being concentrated into Baume degrees as 50-52, being subsequently cooled to temperature is 10-15 DEG C, is carried out
It is separated by solid-liquid separation, obtains the oxalic acid sodium crystal that purity is 98% or more, the mother liquor of separation of solid and liquid will obtain pure after moisture evaporating completely
The sodium sulfate crystal for spending > 97%, obtained calcium carbonate filter residue are added hydrochloric acid solution and obtain calcium chloride solution return use.
The molal quantity of calcium is the total moles of sulfate radical, oxalate and carbonate in the first filtrate in the calcium chloride solution of addition
Several 1.05-1.1 times, the sodium carbonate of addition are 1.05-1.1 times of calcium molal quantity in filter residue.
Embodiment 1
A kind of preparation method of Large ratio surface cerium oxide, is following steps:
(1) match liquid, technical pure ceric sulfate is configured to the ceric sulfate solution that concentration is 181g/L, and constant temperature is to temperature
It is 41 DEG C, technical pure ammonium carbonate is configured to the sal volatile that concentration is 585g/L, and constant temperature to temperature is 41 DEG C, it will be industrial
Pure oxalic acid is configured to the oxalic acid solution that concentration is 103g/L, and constant temperature to temperature is 41 DEG C；
(2) it reacts, the oxalic acid solution of preparation is put into reaction kettle, and constant temperature to temperature is 40 DEG C, built in reaction kettle
Then cooling coil stirs, mixing speed 110r/min, and the sal volatile of 0.11 times of volume of oxalic acid solution is added, and is added
It finishes and continues to stir 20min, as bottom liquid, then ceric sulfate solution and sal volatile are added in the liquid of bottom, while anti-
Answering at the uniform velocity reduces temperature in kettle, the rate for reducing temperature is 5.5 DEG C/h, the volume flow of ceric sulfate solution and sal volatile
Than for 6.1:1, the ceric sulfate solution and sal volatile total volume that amount to addition are 1.25 times of bottom liquid product, sulfuric acid is added
The time of high cerium solution and sal volatile is 3.5 hours, and reaction kettle stops cooling after charging, and this temperature is maintained to stir
1.35h is reacted, is then separated by solid-liquid separation, obtains the first filtrate and the first filter residue, pure water is added to washing in the first filter residue
The 180 μ S/cm of conductivity of water is washed, then dries to moisture content and is lower than 1%, 180 meshes are crossed after broken, are sieved
Material；
(3) it calcines, step (2) sieving materials is calcined in rotary kiln, calcination temperature is 355 DEG C, and calcination time 5.5 is small
When, then by it is broken, sieve to get.
Ceric sulfate solution, sal volatile and the oxalic acid solution prepared in the step (1) make after secondary filter
With the aperture of filter medium is 0.8 micron.
It is at the uniform velocity to be added that bottom liquid process, which is added, with sal volatile in ceric sulfate solution in the step (2), and equipment is added
For peristaltic pump.
Calcium chloride solution is added in first filtrate obtained in the step (2), is stirred to react 1.5 hours, then filters, washes
It washs, condensing crystallizing obtains ammonia chloride crystal after filtrate and wash water are merged, and filter residue is added sodium carbonate liquor and carries out pulp, then again
After temperature is 73 DEG C of reactions 1.2 hours, then filters, obtain the filtrate and calcium carbonate filter residue containing sodium sulphate and sodium oxalate, contain
Having the filtrate of sodium sulphate and sodium oxalate process to be concentrated into Baume degrees is 51, and being subsequently cooled to temperature is 12 DEG C, is separated by solid-liquid separation,
The oxalic acid sodium crystal that purity is 98% or more is obtained, the mother liquor of separation of solid and liquid will obtain purity >'s 97% after moisture evaporating completely
Sodium sulfate crystal, obtained calcium carbonate filter residue are added hydrochloric acid solution and obtain calcium chloride solution return use.
The molal quantity of calcium is the total moles of sulfate radical, oxalate and carbonate in the first filtrate in the calcium chloride solution of addition
Several 1.08 times, the sodium carbonate of addition are 1.08 times of calcium molal quantity in filter residue.
The index of finally obtained Large ratio surface cerium oxide of the invention is as follows:
Embodiment 2
A kind of preparation method of Large ratio surface cerium oxide, is following steps:
(1) match liquid, technical pure ceric sulfate is configured to the ceric sulfate solution that concentration is 182g/L, and constant temperature is to temperature
It is 40 DEG C, technical pure ammonium carbonate is configured to the sal volatile that concentration is 585g/L, and constant temperature to temperature is 40 DEG C, it will be industrial
Pure oxalic acid is configured to the oxalic acid solution that concentration is 103g/L, and constant temperature to temperature is 40 DEG C；
(2) it reacts, the oxalic acid solution of preparation is put into reaction kettle, and constant temperature to temperature is 41 DEG C, built in reaction kettle
Then cooling coil stirs, mixing speed 108r/min, and the sal volatile of 0.105 times of volume of oxalic acid solution is added, and is added
It finishes and continues to stir 23min, as bottom liquid, then ceric sulfate solution and sal volatile are added in the liquid of bottom, while anti-
Answering at the uniform velocity reduces temperature in kettle, the rate for reducing temperature is 5.3 DEG C/h, the volume flow of ceric sulfate solution and sal volatile
Than for 6.05:1, the ceric sulfate solution and sal volatile total volume that amount to addition are 1.45 times of bottom liquid product, sulphur is added
The time of the high cerium solution of acid and sal volatile is 3.8 hours, and reaction kettle stops cooling after charging, and this temperature is maintained to stir
Reaction 1.15h is mixed, is then separated by solid-liquid separation, obtains the first filtrate and the first filter residue, pure water is added extremely in the first filter residue
Then the 225 μ S/cm of conductivity of washing water is dried to moisture content and is lower than 1%, 185 meshes are crossed after broken, are sieved
Material；
(3) it calcines, step (2) sieving materials is calcined in rotary kiln, calcination temperature is 352 DEG C, and calcination time 5.7 is small
When, then by it is broken, sieve to get.
Ceric sulfate solution, sal volatile and the oxalic acid solution prepared in the step (1) make after secondary filter
With the aperture of filter medium is 0.85 micron.
It is at the uniform velocity to be added that bottom liquid process, which is added, with sal volatile in ceric sulfate solution in the step (2), and equipment is added
For metering pump.
Calcium chloride solution is added in first filtrate obtained in the step (2), is stirred to react 1.4 hours, then filters, washes
It washs, condensing crystallizing obtains ammonia chloride crystal after filtrate and wash water are merged, and filter residue is added sodium carbonate liquor and carries out pulp, then again
After temperature is 73 DEG C of reactions 1.8 hours, then filters, obtain the filtrate and calcium carbonate filter residue containing sodium sulphate and sodium oxalate, contain
Having the filtrate of sodium sulphate and sodium oxalate process to be concentrated into Baume degrees is 51, and being subsequently cooled to temperature is 13 DEG C, is separated by solid-liquid separation,
The oxalic acid sodium crystal that purity is 98% or more is obtained, the mother liquor of separation of solid and liquid will obtain purity >'s 97% after moisture evaporating completely
Sodium sulfate crystal, obtained calcium carbonate filter residue are added hydrochloric acid solution and obtain calcium chloride solution return use.
The molal quantity of calcium is the total moles of sulfate radical, oxalate and carbonate in the first filtrate in the calcium chloride solution of addition
Several 1.08 times, the sodium carbonate of addition are 1.09 times of calcium molal quantity in filter residue.
The index of finally obtained Large ratio surface cerium oxide of the invention is as follows:
Embodiment 3
A kind of preparation method of Large ratio surface cerium oxide, is following steps:
(1) match liquid, technical pure ceric sulfate is configured to the ceric sulfate solution that concentration is 184g/L, and constant temperature is to temperature
It is 40.5 DEG C, technical pure ammonium carbonate is configured to the sal volatile that concentration is 585g/L, and constant temperature to temperature is 40 DEG C, by work
The pure oxalic acid of industry is configured to the oxalic acid solution that concentration is 101g/L, and constant temperature to temperature is 40 DEG C；
(2) it reacts, the oxalic acid solution of preparation is put into reaction kettle, and constant temperature to temperature is 41 DEG C, built in reaction kettle
Then cooling coil stirs, mixing speed 115r/min, and the sal volatile of 0.115 times of volume of oxalic acid solution is added, and is added
It finishes and continues to stir 25min, as bottom liquid, then ceric sulfate solution and sal volatile are added in the liquid of bottom, while anti-
Answering at the uniform velocity reduces temperature in kettle, the rate for reducing temperature is 5.3 DEG C/h, the volume flow of ceric sulfate solution and sal volatile
Than for 6.12:1, the ceric sulfate solution and sal volatile total volume that amount to addition are 1.35 times of bottom liquid product, sulphur is added
The time of the high cerium solution of acid and sal volatile is 3.8 hours, and reaction kettle stops cooling after charging, and this temperature is maintained to stir
Reaction 1.3h is mixed, is then separated by solid-liquid separation, obtains the first filtrate and the first filter residue, pure water is added to washing in the first filter residue
The 215 μ S/cm of conductivity of water is washed, then dries to moisture content and is lower than 1%, 190 meshes are crossed after broken, are sieved
Material；
(3) it calcines, step (2) sieving materials is calcined in rotary kiln, calcination temperature is 355 DEG C, and calcination time 5.7 is small
When, then by it is broken, sieve to get.
Ceric sulfate solution, sal volatile and the oxalic acid solution prepared in the step (1) make after secondary filter
With the aperture of filter medium is 0.8 micron.
It is at the uniform velocity to be added that bottom liquid process, which is added, with sal volatile in ceric sulfate solution in the step (2), and equipment is added
For peristaltic pump.
Calcium chloride solution is added in first filtrate obtained in the step (2), is stirred to react 1.7 hours, then filters, washes
It washs, condensing crystallizing obtains ammonia chloride crystal after filtrate and wash water are merged, and filter residue is added sodium carbonate liquor and carries out pulp, then again
After temperature is 73 DEG C of reactions 1.7 hours, then filters, obtain the filtrate and calcium carbonate filter residue containing sodium sulphate and sodium oxalate, contain
Having the filtrate of sodium sulphate and sodium oxalate by being concentrated into Baume degrees is 51.5, and being subsequently cooled to temperature is 13 DEG C, carries out solid-liquid point
From obtaining the oxalic acid sodium crystal that purity is 98% or more, the mother liquor of separation of solid and liquid will obtain purity > after moisture evaporating completely
97% sodium sulfate crystal, obtained calcium carbonate filter residue are added hydrochloric acid solution and obtain calcium chloride solution return use.
The molal quantity of calcium is the total moles of sulfate radical, oxalate and carbonate in the first filtrate in the calcium chloride solution of addition
Several 1.06 times, the sodium carbonate of addition are 1.09 times of calcium molal quantity in filter residue.
The index of finally obtained Large ratio surface cerium oxide of the invention is as follows:
The products application of the embodiment 1 of phase homogenous quantities, embodiment 2, embodiment 3 is catalyzed in purifying vehicle exhaust, is implemented
Example 1 makes nitrogen oxides in vehicle exhaust, carbon monoxide, hydrocarbon oxidation catalyst conversion ratio be respectively 99%, 99.1% and
98.7%, embodiment 2 makes nitrogen oxides in vehicle exhaust, carbon monoxide, the hydrocarbon oxidation catalyst conversion ratio to be respectively
99.1%, 99.2% and 98.8%, embodiment, 3 make nitrogen oxides in vehicle exhaust, carbon monoxide, hydrocarbon oxidation catalyst
Conversion ratio is respectively 99.2%, 99.2% and 98.9%, and the Large ratio surface cerium oxide conventional on the market of phase homogenous quantities makes
The equal < 96% of nitrogen oxides, carbon monoxide, hydrocarbon oxidation catalyst conversion ratio in vehicle exhaust.
Finally, it is stated that the above examples are only used to illustrate the technical scheme of the present invention and are not limiting, although referring to compared with
Good embodiment describes the invention in detail, those skilled in the art should understand that, it can be to skill of the invention
Art scheme is modified or replaced equivalently, and without departing from the objective and range of technical solution of the present invention, should all be covered at this
In the scope of the claims of invention.
Claims (5)
1. a kind of preparation method of bigger serface cerium oxide, which is characterized in that be following steps:
(1) match liquid, technical pure ceric sulfate is configured to the ceric sulfate solution that concentration is 180-185g/L, and constant temperature is to temperature
Be 40 ± 2 DEG C, by technical pure ammonium carbonate be configured to concentration be 550-600g/L sal volatile, and constant temperature to temperature be 40 ±
2 DEG C, technical pure oxalic acid is configured to the oxalic acid solution that concentration is 100-105g/L, and constant temperature to temperature is 40 ± 2 DEG C；
(2) it reacts, the oxalic acid solution of preparation is put into reaction kettle, and constant temperature to temperature is 40 ± 2 DEG C, it is cold built in reaction kettle
But then coil pipe stirs, mixing speed 100-120r/min, and the ammonium carbonate that 0.1-0.12 times of volume of oxalic acid solution is added is molten
Liquid, addition, which finishes, to be continued to stir 15-30min, and as bottom liquid, ceric sulfate solution and sal volatile are then added to bottom liquid
In, temperature is at the uniform velocity reduced in simultaneous reactions kettle, the rate for reducing temperature is 5-6 DEG C/h, ceric sulfate solution and sal volatile
Volume flow ratio be 6-6.2:1, amount to addition ceric sulfate solution and sal volatile total volume be bottom liquid product 1-
1.5 times, the time that ceric sulfate solution and sal volatile is added is 3-4 hours, and reaction kettle stops cooling after charging, and
It maintains this temperature to be stirred to react 1-1.5h, is then separated by solid-liquid separation, obtain the first filtrate and the first filter residue, the first filter residue is added
Enter the conductivity 150-250 μ S/cm of pure water to washing water, then dries to moisture content and be lower than 1%, the mistake after broken
150-200 mesh, obtains sieving materials；
(3) it calcines, step (2) sieving materials is calcined in rotary kiln, calcination temperature is 340-360 DEG C, and calcination time 5-6 is small
When, then by it is broken, sieve to get.
2. a kind of preparation method of bigger serface cerium oxide according to claim 1, it is characterised in that: the step
(1) ceric sulfate solution, sal volatile and the oxalic acid solution prepared in use after secondary filter, the aperture of filter medium
It is 0.5-1 microns.
3. a kind of preparation method of bigger serface cerium oxide according to claim 1, it is characterised in that: the step
(2) it is at the uniform velocity to be added that bottom liquid process, which is added, with sal volatile in ceric sulfate solution in, and it is peristaltic pump or metering pump that equipment, which is added,
At least one of.
4. a kind of preparation method of bigger serface cerium oxide according to claim 1, it is characterised in that: the step
(2) calcium chloride solution is added in the first filtrate obtained in, is stirred to react 1-2 hours, is then filtered, washed, by filtrate and wash water
Condensing crystallizing obtains ammonia chloride crystal after merging, and filter residue is added sodium carbonate liquor and carries out pulp, and then temperature is 70-75 DEG C anti-again
It after answering 1-2 hours, then filters, obtains the filtrate and calcium carbonate filter residue containing sodium sulphate and sodium oxalate, contain sodium sulphate and grass
The filtrate of sour sodium is 50-52 by being concentrated into Baume degrees, and being subsequently cooled to temperature is 10-15 DEG C, is separated by solid-liquid separation, is obtained pure
The oxalic acid sodium crystal that degree is 98% or more, the mother liquor of separation of solid and liquid will obtain the sodium sulphate of purity > 97% after moisture evaporating completely
Crystal, obtained calcium carbonate filter residue are added hydrochloric acid solution and obtain calcium chloride solution return use.
5. a kind of preparation method of bigger serface cerium oxide according to claim 4, it is characterised in that: the chlorine of addition
The molal quantity for changing calcium in calcium solution is 1.05-1.1 times of the total mole number of sulfate radical, oxalate and carbonate in the first filtrate,
The sodium carbonate of addition is 1.05-1.1 times of calcium molal quantity in filter residue.
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| JPH05270823A (en) * | 1992-03-23 | 1993-10-19 | Santoku Kinzoku Kogyo Kk | Multiple oxide capable of absorbing and desorbing oxygen and its production |
| CN104386732A (en) * | 2014-11-17 | 2015-03-04 | 赣州有色冶金研究所 | Method and system for preparing nano cerium oxide by adopting adsorption and isolation agent |
| CN106800307A (en) * | 2017-01-22 | 2017-06-06 | 海城海美抛光材料制造有限公司 | A kind of preparation method of particle in the small apparent density cerias of more than 60um |
| CN106953111A (en) * | 2016-12-09 | 2017-07-14 | 北京科技大学 | A kind of preparation method of samarium doping cerium oxide solid electrolyte powder |
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Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05270823A (en) * | 1992-03-23 | 1993-10-19 | Santoku Kinzoku Kogyo Kk | Multiple oxide capable of absorbing and desorbing oxygen and its production |
| CN104386732A (en) * | 2014-11-17 | 2015-03-04 | 赣州有色冶金研究所 | Method and system for preparing nano cerium oxide by adopting adsorption and isolation agent |
| CN106953111A (en) * | 2016-12-09 | 2017-07-14 | 北京科技大学 | A kind of preparation method of samarium doping cerium oxide solid electrolyte powder |
| CN106800307A (en) * | 2017-01-22 | 2017-06-06 | 海城海美抛光材料制造有限公司 | A kind of preparation method of particle in the small apparent density cerias of more than 60um |
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