Transcript synthetic cordierite - Інститут Проблем Матеріалознавства ім.І.М

National Academy of Science of Ukraine
Frantsevich 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 (2MgO2Al2O35SiO2) 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)
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.
а
б
Area of compositions of threefold system 2MgO2Al2O35SiO2, close to stochiometric cordierite, with
min. low thermal expansion, made by:
а) crystallization of quenched glasses; б) solid-phase synthesis.
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-110-6 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.
0,15
Properties of porous ceramics based on
synthetic cordierite
- - - Corning Corp.
D l/l, %
0,1
0,05
3
4
2
1
Open porosity,%
Density, g/cm3
Temperature coefficient of
expansion 20-800 оС, оС10-6
Maximum operating temperature, °C
0
-0,05
0
100
200
300
400 500
T, oC
600
700
22-24
1,90
1,0-1,2
1200
800
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.
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 Ukraine
Frantsevich Institute for Problems of Materials Science
CATALYTIC NEUTRALIZERS FOR AUTOMOBILES WITH GASOLINE ENGINE
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
The catalytic converter intended for
agent from adamant is put, which improves in dozens of times (up to 15-16
complex сleaning from CO, NOx, CxHy m2/g) specific surface and ternary platinum-paladium-ruthenic catalyst.
of exhaust gases of the automobiles
The contents of active components - platinum metals is 3,5 g on kg of the
using not ethylated variety of benzine.
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
Number
of channels in a
crosssection
on1sm2
Dimensions of
the block,
mm
Synthetic
cordierite
d=95-100
49
h=100200
СО removal
100
80
IPMS
60
40
20
0
100 175
100
80
60 IPMS
40
20
0
100 175
Advantages
1. Reduced starting
oxidizing reaction
temperature
2. Reduced
temperature of 100
%transformation
3. Economy of
platinum metals - up to
30 %
Dimensions
of the
channel,mm
Thickness of
a wall,
mm
Starting СО, NOx,
CxHy oxidizing
reaction
temperature, oC
Temperature
of 100 %
СО,NOx,
CxHy,
conversion,
оС
1х1
0,2
230,
50 % conversion
400
Results of the test performance catalytic converter at
different temperatures
Walker
Linda Gobex
220
250 280
t ex. gases
350
425
СхНу removal
Walker
Linda Gobex
220
250
tex.gases
280
350
425
Conversion, %
effectiveness, %
effectiveness, %
Material
Catalytic afterburner
100
90
80
70
60
50
40
30
20
10
0
170
230
280
CO
370
T, oC
NO CxHy
420
450
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 Ukraine
Frantsevich Institute for Problems of Materials Science
CERAMIC 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.
Limiting operating temperature, оС
Specific surface,
m2
/
m3
20
1200
0
700-1000
5
General surface, m2
DNOx
DD
DCO
Test results efficiency particulate filter with catalytic
coating at different temperatures
Ceramic sooty filter with a catalytic coat
Commercial advantages
1.
Cylindrical monolite dimensions, mm
2.
Dimensions of the channel, mm
3.
Wall thickness of the channel, mm
4.
Catalytic coat on the basis of oxides of the
transition metals
5.
Trapping of particles depending on their size, %
6.
Hydraulic resistance
at air consumption 300 kg/h, sm of water
column
40-60
Temperature of 100 % СО,NOx, CxHy,
conversion, оС
420
7.
60
t=38 oC
5
0,6-0,9
t=300o C
Coefficient of thermal expansion in the
temperature range 20-800 оС, оС-1  10-6
40
t=250o C
1,5
C
t=385 o C
Density, g / sm3
65
60
o
10-15
t=300 C
Average pore size, micron
90
76
74
80
o
55-60
t=250
Open porosity , %
94 98
100
%
Ceramic material - synthetic cordierite
d=120 mm; h=150 mm
44
1
Temperature of soot oxidizing is
comparable to temperature of EIC’s
exhausts – automatic filter
regeneration
Oxidizing of soot at 380-400
оС
95, starting with 10 nm
Trapping of soot nano particles
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”).
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 Ukraine
Frantsevich Institute for Problems of Materials Science
CERAMIC 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.
Key performance of ceramic filters
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 expansion
in the temperature range 20-800 оС,
оС-110-6
5,8
Number of cycles (initial-maximum
operating temperature)
5
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]