national academy of science of ukraine frantsevich institute for problems of materials science
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Manufacturing of the cordierite ceramics as a single-phase product is among enough difficult physicochemical and technological processes. - PowerPoint PPT PresentationTRANSCRIPT
National Academy of Science of UkraineFrantsevich Institute for Problems of Materials Science
SYNTHETIC CORDIERITE AND PRODUCTS BASED ON IT
Manufacturing of the cordierite ceramics as a single-phase product is among enough difficult physicochemical and technological processes.
Complexity of a cordierite (2MgO2Al2O35SiO2) synthesis with the high (95-98 vol. %) contents of a main phase determines by that cordierite forming oxides like magnesia, alumina, silicon oxide have high melting points - 2800, 2030 and 1700 оС accordingly, and sintering at 1600 оС. In the same a time the low temperature of incongruous melting cordierite - 1460 оС does not allow to elevate the temperature of its synthesis above 1400 оС.
Thermal resistant ceramic material (synthetic cordierite) Thermal resistant ceramic material (synthetic cordierite) Fundamental bases of the directed synthesis of cordierite with the low (2-3 vol. %) contents of extrinsic phases by solid-phase sintering in an interval of temperatures 1000-1380 оС and crystallization of quenched glasses are developed in IPMS NASU. The area of the compositions close to stochiometric cordierite, with min. low thermal expansion is determined.
Area of compositions of threefold system 2MgO2Al2O35SiO2, close to stochiometric cordierite, with min. low thermal expansion, made by:
а) crystallization of quenched glasses; б) solid-phase synthesis.
а б
The manufacturing methods for new high spalling-resistant dense and porous (22-24, 45-50 %) ceramic materials with reduced TKLE (0,8-1,2 оС-110-6 in limits 20-800 оС, fig. 2) and increased mechanical strength for carrying agents of catalysts and sooty filters are developed on the basis of synthetic cordierite.
Dilatometric curves of the cordierite exploratory samples, obtained by a solid-phase synthesis (1), crystallization of quenched glasses (2), quartz glass (3), and a sample cut from the catalytic block of Сornіng Corporatіon production.
Open porosity,%Density, g/cm3
Temperature coefficient of expansion 20-800 оС, оС10-6
Maximum operating temperature, °C
22-241,90
1,0-1,21200
Properties of porous ceramics based on synthetic cordierite
Аuthors: Frantsevich Institute for Problems of Materials Science, NAS of Ukraine, Department 4, Doctor V. Pavlikov, Doctor V. Garmash, Phone. +380(44)4242001, e-mail:[email protected]
National Academy of Science of UkraineFrantsevich Institute for Problems of Materials Science
CATALYTIC NEUTRALIZERS FOR AUTOMOBILES WITH GASOLINE ENGINECATALYTIC NEUTRALIZERS FOR AUTOMOBILES WITH GASOLINE ENGINE
The catalytic converter intended for complex сleaning from CO, NOx, CxHy of exhaust gases of the automobiles using not ethylated variety of benzine.
The converter represents the synthetic cordierite ceramic block with cellular structure of the cylindrical form with volume from 1 litre. On a surface of internal channels the shallow layer of the secondary carrying agent from adamant is put, which improves in dozens of times (up to 15-16 m2/g) specific surface and ternary platinum-paladium-ruthenic catalyst. The contents of active components - platinum metals is 3,5 g on kg of the ceramic carrying agent. Complex catalyst with replacement of a part of platinum with oxide of rare-earth metal is developed and passes test.
Ceramic block Catalytic afterburner Advantages
Material Dimen-sions of the block, mm
Number of chan-nels in a cross-section on1sm2
Dimen-sions of the chan-nel,mm
Thick-ness of a wall, mm
Starting СО, NOx, CxHy oxidizing reaction temperature, oC
Temperature of 100 % СО,NOx, CxHy, conversion, оС
1. Reduced starting oxidizing reaction temperature 2. Reduced temperature of 100 %transformation 3. Economy of platinum metals - up to 30 %
Synthetic cordierite
d=95-100h=100-200
49 1х1 0,2 230,50 % conversion
400
Walker
Linda Gobex
IPMS
СО removal
IPMS Walker
Linda Gobex
СхНу removal
0102030405060708090
100
170 230 280 370 420 450T, oC
Co
nve
rsio
n, %
CO NO CxHy
Results of the test performance catalytic converter at different temperatures
Аuthors: Frantsevich Institute for Problems of Materials Science, NAS of Ukraine, Department 4, Doctor V. Pavlikov, Doctor V. Garmash, Phone. +380(44)4242001, e-mail:[email protected]
National Academy of Science of UkraineFrantsevich Institute for Problems of Materials Science
CERAMIC PARTICULATE FILTER WITH CATALYTIC COATINGCERAMIC PARTICULATE FILTER WITH CATALYTIC COATING
The filter represents the ceramic cylindrical monolyte with cellular structure and volume up to 3 litres. Material of the block is synthetic cordierite. On a surface of internal channels and pores the shallow layer of the secondary carrying agent and the catalyst on the basis of oxides of transition metals is put.
Ceramic material - synthetic cordierite
Open porosity , % 55-60
Average pore size, micron 10-15
Density, g / sm3 1,5
Coefficient of thermal expansion in the temperature range 20-800 оС, оС-1 10-6 0,6-0,9
Limiting operating temperature, оС 1200
Specific surface, m2 / m3 700-1000
General surface, m2 5
Ceramic sooty filter with a catalytic coat Commercial advantages
1. Cylindrical monolite dimensions, mm d=120 mm; h=150 mm Temperature of soot oxidizing is comparable to temperature of EIC’s exhausts – automatic filter regeneration
2. Dimensions of the channel, mm 44
3. Wall thickness of the channel, mm 1
4. Catalytic coat on the basis of oxides of the transition metals
Oxidizing of soot at 380-400 оС
5. Trapping of particles depending on their size, % 95, starting with 10 nm Trapping of soot nano particles
6. Hydraulic resistance at air consumption 300 kg/h, sm of water column
40-60
7. Temperature of 100 % СО,NOx, CxHy, conversion, оС
420
Developed sooty filters can be used for making two-stage system of catalytic neutralization of exhaust gases, starting from low temperatures (start and warming-up of the drive) when traditional catalytic neutralizers are insufficiently effective (so-called problem of "cool start”).
C
0
20
40
60
100
%
74
94 9890
76
60
t=25
0 o
COt=
300 o
C
t=38
5 o
C
t=25
0 oC
t=30
0 oC
t=38
5
o C
8065
D NOx
Аuthors: Frantsevich Institute for Problems of Materials Science, NAS of Ukraine, Department 4, Doctor V. Pavlikov, Doctor V. Garmash, Phone. +380(44)4242001, e-mail:[email protected]
Test results efficiency particulate filter with catalytic coating at different temperatures
National Academy of Science of UkraineFrantsevich Institute for Problems of Materials Science
CERAMIC FILTERS FOR MELTS OF METALSCERAMIC FILTERS FOR MELTS OF METALS
Filters with honeycomb and cellular structure for refining (filtration) metal melts at a temperature operation up to 1650 ° C are based on synthetic mullite and mulite-zircon using domestic raw materials (kaolin, zircon, alumina). In combination with low temperature synthesis of mullite (1500-1550 ° C) ceramic filters based on mullite and mulite-zircon can be competitive in the CIS markets.
Аuthors: Frantsevich Institute for Problems of Materials Science, NAS of Ukraine, Department 4, Doctor V. Pavlikov, Doctor V. Garmash, Phone. +380(44)4242001, e-mail:[email protected]
Material mullite, mulite-zircon
Channel sizes, mm 0,5-4
Channels of 1 cm2 8-47
Thickness of the channel wall, mm 1
Maximum operating temperature, ° C 1650
Porosity,% 50-70
Specific surface, cm2 / g >4х104
Compressive strength, MPa >10
Coefficient of thermal expansionin the temperature range 20-800 оС, оС-110-6
5,8
Number of cycles (initial-maximum operating temperature)
5
Key performance of ceramic filters