CA1155827A - Catalyst structure including glass fiber product - Google Patents
Catalyst structure including glass fiber productInfo
- Publication number
- CA1155827A CA1155827A CA000390256A CA390256A CA1155827A CA 1155827 A CA1155827 A CA 1155827A CA 000390256 A CA000390256 A CA 000390256A CA 390256 A CA390256 A CA 390256A CA 1155827 A CA1155827 A CA 1155827A
- Authority
- CA
- Canada
- Prior art keywords
- catalyst
- glass
- cloth
- glass fiber
- holding layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Landscapes
- Catalysts (AREA)
Abstract
ABSTRACT OF THE DISCLOSURE
A catalyst structure comprises a shape retaining metal core of the desired shape, a particle holding layer attached to the core and made of a glass fiber product and catalyst particles held in the layer.
A catalyst structure comprises a shape retaining metal core of the desired shape, a particle holding layer attached to the core and made of a glass fiber product and catalyst particles held in the layer.
Description
1 155~27 The present invention relates to novel catalyst struc-tures prepared with use of glass fiber products.
Granular catalysts 5 to 10 mm in size have been generally used for vapor-phase catalytic reaction systems. Such catalysts have been found empirically favorable with respect to minimizing pressure loss of the reactant gas in the catalyst layer and minimizing clogging of the catalyst layer, and further from the viewpoint of economy. On the other hand, however, such granular catalysts do not permit gaseous reactants to diffuse into the catalyst effectively, that is, fail to permit a high rate of mass transfer. A great difference therefore occurs in the reactant concentration within the grains or pellets, with the result that the catalyst is low in the effectiveness factor defined by Thiele et al. Thus there is the likelihood that almost all the charge of catalyst is unable to function substantially effectively.
The low catalyst effectiveness factor poses a serious problem with expensive noble metal catalysts and is very unfavorable A ~,~
1 ~55827 economically even in th. case oL re~Lallvely incxpensive catalysts o~ metallic oxides ln resp(-ct oi` the pressure loss of l~eactant gaC;eS~ ~he size o~ the reactor, -the ~electivi-ty oL react;ion, etc.
Generally catalysts for use in indus-tries must f`ulfill the Lollowing requirements:
1) High activity per unit weight o~ the catalys-t.
Granular catalysts 5 to 10 mm in size have been generally used for vapor-phase catalytic reaction systems. Such catalysts have been found empirically favorable with respect to minimizing pressure loss of the reactant gas in the catalyst layer and minimizing clogging of the catalyst layer, and further from the viewpoint of economy. On the other hand, however, such granular catalysts do not permit gaseous reactants to diffuse into the catalyst effectively, that is, fail to permit a high rate of mass transfer. A great difference therefore occurs in the reactant concentration within the grains or pellets, with the result that the catalyst is low in the effectiveness factor defined by Thiele et al. Thus there is the likelihood that almost all the charge of catalyst is unable to function substantially effectively.
The low catalyst effectiveness factor poses a serious problem with expensive noble metal catalysts and is very unfavorable A ~,~
1 ~55827 economically even in th. case oL re~Lallvely incxpensive catalysts o~ metallic oxides ln resp(-ct oi` the pressure loss of l~eactant gaC;eS~ ~he size o~ the reactor, -the ~electivi-ty oL react;ion, etc.
Generally catalysts for use in indus-tries must f`ulfill the Lollowing requirements:
1) High activity per unit weight o~ the catalys-t.
2) High activity per unit vol~ne of the reactor.
3) ~alall pressure loss of the reactant gases in the catalyst layer.
4) High overall strength enabling -the catalys-t to fully vli-thstand the impact of charging.
5) High surface strength against -the external forces to be exerted on the catalyst during use.-/
~) Reduced variations in activi-ty despite the lapse of time.
7) ~ow CoGt.
The true activity of a catalyst, free fro~
rnass transfer resistance, per unit weight thereof is dependent on the composition of the catalyst, the structure of the crystals thereof, etc. and is inherent in the catalyst, but the actual activity varies with the grain eiæe, the pore structure of the grain, the flow rate, i.e.
linear velocity, of the reactant gas, etc. Generally the activity increases with decreasing grain size, ncrea~in~ Pore size, incre~sin~ l)ore vollime an~i nc~ea~in~ L`low rate of` the react~lrlt ~;ac,. Nevertheless, the~e l~lctors contribu-ting to the lncreElse ol'' ac-tivi-ty are entirely in conI'lict with the require~ments in respect of` the reac-tant gas pressure lo~,s and catalyst strength.
Accordingly it is extremely dilficult -to l`ull'ill all the f`oregoing requirements l) to 7).
In order to satisfy -t'le above requirements l) to 7), several catalysts OI the honeycomb tvpe have been ~eveloped in recent years. These catalysts include those prepared by forming a paste from a catalytic component and a binder, extruding the paste into a honeycomb body and baking the body under suitable condi-tions, and those prepared by making a honeycomb s-tructure from ceramics having no catalytic ac-tivity and depositing a cataly-tic component on the surface of the structure with a binder.
Ylith the former catalysts, there is the need to form a honeycomb body with a large wall thicknese~ and to obtain a compacted baked 'body which is less amenable to the diffusion of reactant gases into the catalyst, in order to give the desired strength to the catalyst. It is therefore impossible to afford an improved catalyst effectiveness f'actor. Thus difficulties are encountered in improving both strength and activity at the same time.
With the latter oase, the to~gh ceramics horeycomb structure has ideal overall strength, fulfilling the requirement 4), but the use of the binder reduces the inherent activity of the catalyst. Further the layer of deposited catalytic component, which is made very thin to assure high surface strength 5) and high activity per unit weight 1), reduces the activity per unit volume of the reactor 2) and impairs the stability of reaction.
SUMMARY OF THE INVENTION
The main object of the present invention, which has been accomplished in view of the foregoing problems, is to provide novel catalyst structures better adapted to meet the foregoing require-ments 1) to 7) for industrial catalysts.
The invention provides a catalyst structure comprising a shape retaining metal core having a desired shape, a catalyst particle holding layer attached to the core and made of a glass fiber product having a plurality of filament-to-filament inter-stices, and catalyst particles held in the interstices of the hold-ing layer.
The invention will further be described, by way of example, only, with reference to the accompanying drawings, wherein:-~ - 4 -.~, BRIF,i~ S~RIP~ N ~ Hl, ~RA~'IlNG', !~'igs. 1 ~ln,d 2 are sectional views showing sandwich-type c~-talys-t c,truc-turec,;
l~'igs. 3 and 4 arC,- front views partl,y in section and showing col~nnar catalyst structures;
l~'ig. 5 is a gr.lph showing the relation between the concentra-tion of slurry and t;he amount of' ~articles held by glass clo-th;
~ ig. 6 is a view in vertical section showing a reactor;
E'ig. 7 is a graph showing reactivi-ties and selectivities at varying reaction temperatures; and Fig. 8 is a pers?ective view showing a reactor.
DESCRIPTION 0~' THE PRE~'ERRED E~IBOD~IENl'S
The ~hape retaining core gives the desired overall ~trength to the catalyst structure. The core is in the shape of a flat plate or cylinder or is otherwise shaped suitably in accordance with the shape of the reactor. The core is made generally of steel.
IJseful glass fiber products include nonv~oven fabric, paper, rnat, cloth and roving cloth of glass fibers.
Throu~r,hout the specification and the appended claims, these terms rnean the follovling.
The glass nonwoven fabric or glass paper is a planar web of glass filaments which are bonded to one another ~Jit~l an adhesive. 'l`he web is nonvloverl f~bric when long t'lber~ are used, or is paper ~hen short i`ibers are used.
The glass mat is ~repared by forming a wad of specified -thickness i`rom rovings Or glas~ f`ilaments anci rll2,h-ing -the wad into a mat.
The gla5S cloth is woven of' yarns made by twisting from a multiplicity of glass filaments about 5 to 15 ~ in diameter. The weaving method is plain weave~ twill weave, satin weave or the like.
The glass roving cloth is prepared by forming rovings from long glass iibers and ~eevin~ the rovings into a cloth without twisting.
All of' these glass f'iber products ~ e i'ilament-to-filament interstices which hold particles therein and permit dif'fusion of gaseous reactants there-through. Thus these glass f'iber products are useful as a component of the catalyst structure of the invention.
Since the glass nonwoven fabric, paper and mat each have a large number of f'ilament-to-filament interstices, and further because component filaments thereof are easily shiftable relative to one another when subjected to an external ~'orce, they hold a large amount of' cataly~t particles therein. Accordingly these non-~loven fabric, paper and mat are well suited as ~ass f'iber ~r;duct3 L'or formin~ pa~-tlc~le holdin~~L-~!er~-.
i~`ibers are incor~orclted into t;he ~ C; cloth with increacecl tension and wi-th a reduced number of filament--to-filarnent interstice6, whi1e the component 1'i1aments thereof' are lescs shiftable relative to one another, therefore hold a smal]er amount of catalyst par~icles therebetween, but will not permit the release of such p~rticles therefrom when subjected, for exam~le, to vibration. Accordingly the glass cloth is well suited as a glass fiber product for forming the layer for preventing release of particles.
The glass roving cloth as it is is similar to usual cloth, but when the roving cloth is subjected to a needling, brushing or like process to nap one side thereof, the napped surface is given suitable properties to hold ~articles. Accordingly when glass roving cloth having a napped surf'ace is fitted to the core with the napped surface inside, the roving cloth serves as a glass fiber product having the functions of both the particle holding layer and the release preventing layer.
I]seful catalyst particles are those not larger than 100 mesh. Especially particles in the range of 1 to 20 ~ are most preferable since they are easy to hold but diff'icult to release. Particles srnaller than 1 ~ in size are ~omewhat easily releasable but are still satisfacto-1 ~55827 rily IsabLe t~n(ler conc.l~;ions ~'ree ol' st;rong n~echanicalvibrstion. Although par~lc]es exceed:Lng 20 ~ in size have ~il`f`icul-ty in entering ~'ilarnent-to-:t`il.ament inter-~tices of ',he ]ayer, a sufficient amount of` such particles can be held in the la,~er if` the layer is pressed with ruhber rollers a~ i~creased nu~lber of -times as wi]l be described later.
To cause a glass fiber product to hold catalyst particles ? the Produc~ is immersed in a slurry comprlsing water or a suitable dispersing medium and catalyst particles and having a viscosity oI` 100 to l~00 cps. It is deirable to press the glass fiber product wi-th rubber rollers in the slurry to force the slurry into the filament-to-filament in-terstices and the~Je,by cause the product to hold -the par-ticles effectively To squeeze an excess of the slurry from the glass fiber product, the product is then passed between rubber rollers under a pressure of 5 to 30 kg per unit length (m) of the rollers. The wet product is thereafter fitted to a shape retaining core and fixed thereto with fasteners.
The glass f'iber product thus fitted to the core is dried and, when desired, baked. The fiber product may be dried first and then attached to the core. In this case the product will release some amount of dust during handling, so that care should be taken to assure a good work enviror~lent.
In this way, a calaLyct structure of' t,his invention ic~ obt;ained.
~ l'he cat21yst structures o~ this in~rention can be in various forms. Llligs. 1 to 4 sho~ t;~pic21 examples.
l'he catalyst structure shown in ~`ig. 1 is of the candwich type. This drawing shows a metal core 1 in the f'orm of a flat plate, a pair of planar particle holding layers 2 fitted to the opposite sides of the core 1, and fasteners 3 for fixing the layers 2 to the core 1. The catalyst structure shown in ~ig. 2 further includes ~lanar layers 4 for preventing release of catalyst particles which layers are fitted to -the outer sides of the pair of particle holding layers. Fig. 3 shows a columnar catalyst structure comprising a cylindrical metal core 11, a particle holding layer 12 f'i-tted around the core 11, and fasteners 13 for fixing -the layer 12 to the core 11.
Fig. 4 shows a catalyst structure further comprising a release preventing layer 14 covering the particle holding layer 12.
The catalyst structures thus constructed according to the invention have the f'ollowing advantages.
The core, which is made of metal, gives high mechanical strength to the structure.
The particle holding layer, which is a glass _g _ fiber ~?roduc-l, ellec-tively hol~ a large amount of`
cataly~!t particles therein without using any binder, permits efficient cll1`fusion of reactant gases through the interior of` the str~cture Wit~! a reduced pressure loss and a3~ure~ efiective contact between -the gases an~ the catalyst, enablin~ the catalyst to exhibit exceedingly high activity.
The materi~ls of the structure are all inexpensive and easily available.
Accordingly the Gatalyst structures of the invention are ideal and fulfill all the f`oregoing requirements l) to 7).
Reference ~xample l ! Different kinds of particulate materials were checked for differences in the amount of particles held by glass cloth.
A glass cloth was prepared which was 0.2 mm in thickness, 200 g/m2 in weight and l9 yarns/25 mm in yarn density and which was woven of yarns each having one twist/25 mm and composed of 800 glass filaments 14 ~m in diameter. Surries of varying concentrations were prepared by adding water to 200- to 500-mesh particles of r-alumina. A piece of the glass cloth was immersed in each of the slurries and pressed with rollers ~wice in the slurry. The piece o~ glass cloth thus im~regn~ted with the ~ url~y ~.as dried ~t 100 C for l 'rlour and th~n baked or f'i~r?(l at 4()0 C f'or 3 hours.
The amount ol parlicles held in each of' the cloth pieces thus treated ~as measured.
The same proced~lre as above was repeated cxcept that in place of the Y-alumina particles, silica-alurnina partlcles or magnesia ~articles, the same as the r-alumina particles in size, were used. The ~mount of particles held in each of the resulting clo-th pieces was measured.
The relation between the concentration of slurry and the amount of' particles held in the glass cloth was deterrnined f'or each kind of the particles. ~'ig. 5 is a graph showing the results. The graph reveals that the arnount of each kind of particles increases with the increase of the slurry concentration.
Reference ExamPle 2 Diff'erent kinds of glass fiber products were caused to hold particles therein and checked for differences in the amount of the particles.
The same glasæ cloth as used in Reference Example 1 was used as a glass fiber product. Water was added to 200- to 500-rnesh magnesia particles to prepare a slurry havin~ a concentration of 25~ by weight. In the sarne manner as in Reference Example l, the glass cloth was caused -t,o hol(l magrlesia part,ic~es, an~l the ~mount of particlec held therein was meas~red.
The C,eme procedure ac, above was repeated with the exceo-tion oL using ~lass non~oven fabric, mat or roving cloth na-pped on one side ~by needling with 108 needles/cm2) instead of the glass cloth. The amount of magnesia particles held in each of the resulting glass fiber products was measured.
Table 1 shows the results.
rl'able 1 Glass fiber product Particles K d Weight* Amount Amount held/weight 1n (kg/m ) (kg/m3) of fiber product -~loth 1000 550 0.55 Nonwoven 600 520 0.87 Mat 80 650 8.1 Napped roving 470 620 1.32 cloth * Y~eight of product per apparent unit volume of the product.
** Weight of particles per apparent unit volume of the fiber product.
Example 1 ~he same glass cloth as used in Reference Example 1 was caused to hold magnesia particles in the same manner as in ~`~eference Exam~11e 2, and ~Nas then attached to -the opposite ~ides o~` a core o~ stainle~s steel pla-te, 35 mm x 50 mm x 1.5 mm, whereby a cat~lyst struc-~ure A of the sandwich type sho~n in l~'ig. 1 was prepared. Catalys-t structures B, C and D ~ere prepared in the same manner as above except tha-t glass lionwoven fabric, glass mat or glass roving cloth naped on one side was used for the particle holding layers in place of the glass cloth. The roving cloth, the same as -the one used in Reference Example 2, was attached to the steel plate with the napped surface inside.
Example 2 ~ lass nonwoven fabric, mat and cloth were caused to hold magnesia particles therein in -the same manner as in Reference Example 2. In the same manner as in Example 1, the glass nonwoven fabric was attached to a steel panel serving as -the core to provide particle holding layers therei)n. The glass cloth having magnesia particles held therein as above was placed over the holding layers to provide particle release preventing layers thereon, whereby a catalyst structure E of the ~ame construction as shown in Fig. 2 was prepared.
Further a catalyst structure F was prepared in the same manner a~ above except that the above glass mat having magnesia particles held therein was used in place of the glass nonllJo~en f`abrlc to nrovide particle holding layers.
'['~ble ,' shows thc thicknesses and weights of the layers lncluded in the catalyst s-tructures prepared in the foregoing exa~ples, and also the Qmounts of magnesia held ln -the layers.
Tab]e 2 Cata- Holding la~er Preventing ~yer Thick- Amount lyst ness of of` mag-struc- ~'iber Weight ~iber Weight layer* nesia ture product (g~m2) product (g/m2) (mm) (g/m2) A Cloth 200 - - 0.2 llO
Non-B woven 300 - - 5 260 fabric C hiat 400 - - 3 1900 ! Napped J
roving 570 - - 1.2 - 260 cloth Non-E woven 300 Cloth 200 0.8 380 fabric F ~lat 400 Cloth 200 3.1 1900 * The thickness of the particle holding layer or the combined thickness of the holding layer and the particle release preventing layer.
Reference Example 3 The catalyst structures A to ~` were tested for abra~ion resistance.
~ he catalyst structure A was fixed to the center of a 30-mesh metal screen having a diameter of 300 mm, 200 g of alumina ba'lls with a diame-ter of' 5 mm were -~laced into the screen, and the screen was vibrated on an automa-tic screening device (290 vibraiions/min ~ith an amplitude of 30 mm) f'or 4 hours. The amount of catalyst released was measured l hour, 2 hours and 4 hours af'ter the start of the vibration to determine the amount of' particles held in the struc-ture. The same p-rocedure as above was repeated for the catalyst structures B to P'.
Table 3 shows the results.
Table 3 Catalyst Amount of magnesia held (g/m ) structure Initial In 1 hour In 2 hours In 4 hours _ B 260 180 llO 40 1900 llO0 620 120 ~ able 3 reveals that all the structures have great ability to hold particles.
Reference Example 4 The catalyst structures A to F were tested f'or re~i~tance to vibrations.
l'he catalyst structure A was fixed to a 6-mesh metal ~creen and ~ubjected to vibrations for 2 hours by a 50-H~ vibrator mounted on the structure A. The amount of` particles released was measured 0.5 hour, 1 hour and 2 hours after the start of the vibration to determine the amount of particles held in the structure.
I~he same procedure as above was repeated for the catalyst structures ~ to ~. Table 4 shows the results.
Table 4 Catalyst Amount of magnesia held (g/m2~
structure Initial In 0.5 hour In 1 hour In 2 hours B 260 202 145 J~
C 1830 1620 1400 -~ 1250 Table 4 reveals that all the catalysb structures have high resistance to vibrations.
Example 3 A 300 g quantity of a-alumina particles not larger than 200 mesh in size were placed into a solution o~ 11.8 g of a~monium metavanadate, 3.8 g of ammonium molybdate tetrahydrate and 8 g of oxalic acid in 130 g ol water. 'l~he mixture was eva~orated to dryness wi-th stirring in a vacuum at a temperature of up to 60 C
and was iurther fired at 400 C for 3 hours. The fired product was pulverized to obtain 200- to 500-mesh catalyst particles, to which water was aclded to ~prepare a ~lurry having a concentration of 25~ by weight.
A strip of glass roving cloth napped on one side and having a thickness of 1.2 mm, wid-th of 20 mm and weight of 570 g/m2 was immersed in the slurry and pressed with rollers twice in the slurry. The strip thus impregnated with the slurry was fitted, with the nap inside, around a mild steel cylinder 18 mm in diameter and 80 mm in length and fastened thereto at its upper and lower portions. The strip was then dried at 100 ~ for 1 hour and thereafter fired at 400 C for 1 hour, whereby a columnar catalyst structure was prepared which had the construction shown in Fig. 3, with the roving cloth covering measuring 60 mm in length. The amount of particles held in the cloth layer was 240 g/m2.
Activit~ test ~ he columnar catalyst structure (having about 0.9 g of catalyst particles held therein) indicated at 22 and prepared in Example 3 was placed into a large-diameter portion 21, 23 mm in inside diameter, of a reactor of quartz as seen in ~ig. 6. The reactor was 1 ~55827 controlled to a predetermined reaction temper~lture. A
benzene-~ir gaseous mixture (with a benzene concentration o~ ~.8 to o.gqO) was led in~o the reactor throu~h a small-diameter portion 23 at a flow rate of 60 N~/h, and the resulting outflow was collected from the upper end of the large-diameter portion 21 to measure the amount of maleic anhydr~ide formed by the oxida~ion of benzene. The same procedure as above was repeated at vary1ng reaction temperatures. The same procedure as above was further repeated at varying reaction tempera-tures with thè exceptlon o~ using a benzene-air mixture having an increased benzene concentr~ation of 1.2 to 1.3%.
~or comparison, 0.9 g of 6- -to 8-mesh I a-alumina 300 grains were admixed with 9 g o~ - to 8-mesh ~ilica glass grains to obtain a catalyst ln the ~orm of~small pellets, which~was tested for activity under the same conditions as above. ~ig. 6 further shows a heater 24, a molten salt bath 25 and a the~rmo-couple 26.
Reactivities and selectivities were calculated ~rom the above measurements at each of the reaction temperatures acoording to the following equations.
Reactivity - (1 ~ Benzene cConncnn of ¢htargeW)x 100 I
1 1558~7 ~Mount Or maleic anhydride ~electivity = lor~med (mol/h) x lO0 Amount o~ benzene reac-ted (mol/h) The resul-ts are shown in l~'ig. 7, which reveals that the columnar catalyst structure of Example 3 is much more excellent than the pellet cat~lyst in both reactivity and selectivity.
Example 4 To a slurry composed of 30 parts by weight of anatase-type TiO2 particles not larger than 200 mesh and 70 parts by weight of water made acidic with sulfuric acid and having a pH of 2 to 3 was added ammonium meta-vanadate in an amount corresponding to 0.05 in atomicratio relative to the TiO2. The mixture was stirred at room temperature for 5 hours to dissolve -the ammonium metavanadate in the slurry and cause the TiO2 to adsorb the vanadate radical, affording a slurry of TiO2 retaining vanadium therein. Glass roving cloth weighing 300 g/m2 was immersed in the slurry and pressed with rollers twice in the slurry. ~he cloth thus impregnated with the ~lurry was attached to the opposite sides of a stainless steel plate, 50 mm x 29 mm x 0.3 mm, then dried at 150 C for 1 hour and thereafter fired at 400 C for 3 hour~, whereby a catalyst structure G of the sandwich type shown in Fig. l was prepared.
Cata~yst structures H to N were prepared in the same manner as above wi-th the exception of' using the glass fiber products shown in Table 5 in place o~ the glass roving cloth. The napped roving clo-th was used with the nap inside.
Table 5 ~atalyst Glass fiber productNumber ~ 2*
G Xoving cloth (300 ~/m ) O
H Napped roving cloth (300 g/m2) 162 I Napped roving cloth (300 g/m2) 216 J Roving cloth (570 g/m2) 0 K Napped roving cloth (570 g/m2~ 108 L Napped roving clo-th (570 g/m2) .J 216 1~ Nonwoven fabric, (300 g/m ) 1 0.8 mm in thickness N ~loth, 0.2-mm-thick (200 g/m2) * The number of needles used for napping.
Comparison Example One hundred parts by weight of TiO2 powder (not larger than 44 ~ in particle size, and 150 m2/g in ~urface area) and 100 parts by weight of colloidal silica (containing about 2010 by weight of SiO2) serving as a binder were thoroughly mixed together to obtain a slurry.
The slurry was applied to the opposite sides of 18-mesh metal net-ting (30 mm x 50 mm in size an(l macle of ~1rires, 0.5 mm in diameter, of SUS 304 steel), then dried et 100 C ~`or 1 hour and thereafter fired at 400 ~ for 3 hours, whereby a 'liO2 carrier was ~`ormed on the netting in the ~orm of a plate abou-t 0.8 mm in thickness. ri`he netting was immersed in a 2N oxalic acid solut~ion of ammonium metavanadate (1.0 mole/liter) at room temperature for 30 minutes, then withdrawn from the solution, there-after dried at 100 ~ for 1 hour and further fired at about 400 ~ for 3 hours, affording a catalyst 0 having the catalytic component suPported on the metal ne-tting.
Activity test Into a tubular stainless steel reactor 32 having a reactant gas flow channel 31, 6 mm x 30 mm, were placed three catalyst structures 33 as arranged in a row longitudinally of the channel and supported by metal nets 34 a~ shown in ~'ig. 7. A test reaction gas having the composition shown in Table 6 vras passed through the reactor 32 at a flow rate of13 N~/min to test the catalyst for activity to reduce N0 with NH3.
l'able ~
Component Proportion (by volume) N0 Abou-t 150 ppm NH3 About 150 ppm H20 10~/f C o 2 1 05o 2 5%
N2 Balance In this way, the catalyst struct~lres G to N
and catalyst 0 were te~ted for activity at va.rying reaction temperatures to calculate values K defined by:
K = -(AV) x ~n(l-x) l~
where: AV = ~'low rate of reaction gas (Nm3jh) Geometric surface area of cataly~t (m ) x - N0 reactivity 'The relation between K and the amount of TiO2 supported was established. Table 7 shows the results.
Table 7 t,atalystAmount of K
structureT .' 2 200 C 250 C 300 C 350 G 62 10.3 29.8 47.8 69.0 H 255 30.7 66.4 98.9 132 I 3t)5 32.1 ~7-9 100 137 J 7'0 10.9 28.2 41.4 54.1 K 362 35.1 67.0 103 141 L 361 36.7 73.4 122 172 120 17.5 42.2 70.0 99.5 N 65 9.8 24.9 36.2 47-3 0 400 12.3 26.3 40.9 49.4 Table 7 reveals that the catalyst structures G to N of Example 4 have higher K values per unit amount of TiO2 and higher activity than the catalyst 0 of ~omparison Example.
~) Reduced variations in activi-ty despite the lapse of time.
7) ~ow CoGt.
The true activity of a catalyst, free fro~
rnass transfer resistance, per unit weight thereof is dependent on the composition of the catalyst, the structure of the crystals thereof, etc. and is inherent in the catalyst, but the actual activity varies with the grain eiæe, the pore structure of the grain, the flow rate, i.e.
linear velocity, of the reactant gas, etc. Generally the activity increases with decreasing grain size, ncrea~in~ Pore size, incre~sin~ l)ore vollime an~i nc~ea~in~ L`low rate of` the react~lrlt ~;ac,. Nevertheless, the~e l~lctors contribu-ting to the lncreElse ol'' ac-tivi-ty are entirely in conI'lict with the require~ments in respect of` the reac-tant gas pressure lo~,s and catalyst strength.
Accordingly it is extremely dilficult -to l`ull'ill all the f`oregoing requirements l) to 7).
In order to satisfy -t'le above requirements l) to 7), several catalysts OI the honeycomb tvpe have been ~eveloped in recent years. These catalysts include those prepared by forming a paste from a catalytic component and a binder, extruding the paste into a honeycomb body and baking the body under suitable condi-tions, and those prepared by making a honeycomb s-tructure from ceramics having no catalytic ac-tivity and depositing a cataly-tic component on the surface of the structure with a binder.
Ylith the former catalysts, there is the need to form a honeycomb body with a large wall thicknese~ and to obtain a compacted baked 'body which is less amenable to the diffusion of reactant gases into the catalyst, in order to give the desired strength to the catalyst. It is therefore impossible to afford an improved catalyst effectiveness f'actor. Thus difficulties are encountered in improving both strength and activity at the same time.
With the latter oase, the to~gh ceramics horeycomb structure has ideal overall strength, fulfilling the requirement 4), but the use of the binder reduces the inherent activity of the catalyst. Further the layer of deposited catalytic component, which is made very thin to assure high surface strength 5) and high activity per unit weight 1), reduces the activity per unit volume of the reactor 2) and impairs the stability of reaction.
SUMMARY OF THE INVENTION
The main object of the present invention, which has been accomplished in view of the foregoing problems, is to provide novel catalyst structures better adapted to meet the foregoing require-ments 1) to 7) for industrial catalysts.
The invention provides a catalyst structure comprising a shape retaining metal core having a desired shape, a catalyst particle holding layer attached to the core and made of a glass fiber product having a plurality of filament-to-filament inter-stices, and catalyst particles held in the interstices of the hold-ing layer.
The invention will further be described, by way of example, only, with reference to the accompanying drawings, wherein:-~ - 4 -.~, BRIF,i~ S~RIP~ N ~ Hl, ~RA~'IlNG', !~'igs. 1 ~ln,d 2 are sectional views showing sandwich-type c~-talys-t c,truc-turec,;
l~'igs. 3 and 4 arC,- front views partl,y in section and showing col~nnar catalyst structures;
l~'ig. 5 is a gr.lph showing the relation between the concentra-tion of slurry and t;he amount of' ~articles held by glass clo-th;
~ ig. 6 is a view in vertical section showing a reactor;
E'ig. 7 is a graph showing reactivi-ties and selectivities at varying reaction temperatures; and Fig. 8 is a pers?ective view showing a reactor.
DESCRIPTION 0~' THE PRE~'ERRED E~IBOD~IENl'S
The ~hape retaining core gives the desired overall ~trength to the catalyst structure. The core is in the shape of a flat plate or cylinder or is otherwise shaped suitably in accordance with the shape of the reactor. The core is made generally of steel.
IJseful glass fiber products include nonv~oven fabric, paper, rnat, cloth and roving cloth of glass fibers.
Throu~r,hout the specification and the appended claims, these terms rnean the follovling.
The glass nonwoven fabric or glass paper is a planar web of glass filaments which are bonded to one another ~Jit~l an adhesive. 'l`he web is nonvloverl f~bric when long t'lber~ are used, or is paper ~hen short i`ibers are used.
The glass mat is ~repared by forming a wad of specified -thickness i`rom rovings Or glas~ f`ilaments anci rll2,h-ing -the wad into a mat.
The gla5S cloth is woven of' yarns made by twisting from a multiplicity of glass filaments about 5 to 15 ~ in diameter. The weaving method is plain weave~ twill weave, satin weave or the like.
The glass roving cloth is prepared by forming rovings from long glass iibers and ~eevin~ the rovings into a cloth without twisting.
All of' these glass f'iber products ~ e i'ilament-to-filament interstices which hold particles therein and permit dif'fusion of gaseous reactants there-through. Thus these glass f'iber products are useful as a component of the catalyst structure of the invention.
Since the glass nonwoven fabric, paper and mat each have a large number of f'ilament-to-filament interstices, and further because component filaments thereof are easily shiftable relative to one another when subjected to an external ~'orce, they hold a large amount of' cataly~t particles therein. Accordingly these non-~loven fabric, paper and mat are well suited as ~ass f'iber ~r;duct3 L'or formin~ pa~-tlc~le holdin~~L-~!er~-.
i~`ibers are incor~orclted into t;he ~ C; cloth with increacecl tension and wi-th a reduced number of filament--to-filarnent interstice6, whi1e the component 1'i1aments thereof' are lescs shiftable relative to one another, therefore hold a smal]er amount of catalyst par~icles therebetween, but will not permit the release of such p~rticles therefrom when subjected, for exam~le, to vibration. Accordingly the glass cloth is well suited as a glass fiber product for forming the layer for preventing release of particles.
The glass roving cloth as it is is similar to usual cloth, but when the roving cloth is subjected to a needling, brushing or like process to nap one side thereof, the napped surface is given suitable properties to hold ~articles. Accordingly when glass roving cloth having a napped surf'ace is fitted to the core with the napped surface inside, the roving cloth serves as a glass fiber product having the functions of both the particle holding layer and the release preventing layer.
I]seful catalyst particles are those not larger than 100 mesh. Especially particles in the range of 1 to 20 ~ are most preferable since they are easy to hold but diff'icult to release. Particles srnaller than 1 ~ in size are ~omewhat easily releasable but are still satisfacto-1 ~55827 rily IsabLe t~n(ler conc.l~;ions ~'ree ol' st;rong n~echanicalvibrstion. Although par~lc]es exceed:Lng 20 ~ in size have ~il`f`icul-ty in entering ~'ilarnent-to-:t`il.ament inter-~tices of ',he ]ayer, a sufficient amount of` such particles can be held in the la,~er if` the layer is pressed with ruhber rollers a~ i~creased nu~lber of -times as wi]l be described later.
To cause a glass fiber product to hold catalyst particles ? the Produc~ is immersed in a slurry comprlsing water or a suitable dispersing medium and catalyst particles and having a viscosity oI` 100 to l~00 cps. It is deirable to press the glass fiber product wi-th rubber rollers in the slurry to force the slurry into the filament-to-filament in-terstices and the~Je,by cause the product to hold -the par-ticles effectively To squeeze an excess of the slurry from the glass fiber product, the product is then passed between rubber rollers under a pressure of 5 to 30 kg per unit length (m) of the rollers. The wet product is thereafter fitted to a shape retaining core and fixed thereto with fasteners.
The glass f'iber product thus fitted to the core is dried and, when desired, baked. The fiber product may be dried first and then attached to the core. In this case the product will release some amount of dust during handling, so that care should be taken to assure a good work enviror~lent.
In this way, a calaLyct structure of' t,his invention ic~ obt;ained.
~ l'he cat21yst structures o~ this in~rention can be in various forms. Llligs. 1 to 4 sho~ t;~pic21 examples.
l'he catalyst structure shown in ~`ig. 1 is of the candwich type. This drawing shows a metal core 1 in the f'orm of a flat plate, a pair of planar particle holding layers 2 fitted to the opposite sides of the core 1, and fasteners 3 for fixing the layers 2 to the core 1. The catalyst structure shown in ~ig. 2 further includes ~lanar layers 4 for preventing release of catalyst particles which layers are fitted to -the outer sides of the pair of particle holding layers. Fig. 3 shows a columnar catalyst structure comprising a cylindrical metal core 11, a particle holding layer 12 f'i-tted around the core 11, and fasteners 13 for fixing -the layer 12 to the core 11.
Fig. 4 shows a catalyst structure further comprising a release preventing layer 14 covering the particle holding layer 12.
The catalyst structures thus constructed according to the invention have the f'ollowing advantages.
The core, which is made of metal, gives high mechanical strength to the structure.
The particle holding layer, which is a glass _g _ fiber ~?roduc-l, ellec-tively hol~ a large amount of`
cataly~!t particles therein without using any binder, permits efficient cll1`fusion of reactant gases through the interior of` the str~cture Wit~! a reduced pressure loss and a3~ure~ efiective contact between -the gases an~ the catalyst, enablin~ the catalyst to exhibit exceedingly high activity.
The materi~ls of the structure are all inexpensive and easily available.
Accordingly the Gatalyst structures of the invention are ideal and fulfill all the f`oregoing requirements l) to 7).
Reference ~xample l ! Different kinds of particulate materials were checked for differences in the amount of particles held by glass cloth.
A glass cloth was prepared which was 0.2 mm in thickness, 200 g/m2 in weight and l9 yarns/25 mm in yarn density and which was woven of yarns each having one twist/25 mm and composed of 800 glass filaments 14 ~m in diameter. Surries of varying concentrations were prepared by adding water to 200- to 500-mesh particles of r-alumina. A piece of the glass cloth was immersed in each of the slurries and pressed with rollers ~wice in the slurry. The piece o~ glass cloth thus im~regn~ted with the ~ url~y ~.as dried ~t 100 C for l 'rlour and th~n baked or f'i~r?(l at 4()0 C f'or 3 hours.
The amount ol parlicles held in each of' the cloth pieces thus treated ~as measured.
The same proced~lre as above was repeated cxcept that in place of the Y-alumina particles, silica-alurnina partlcles or magnesia ~articles, the same as the r-alumina particles in size, were used. The ~mount of particles held in each of the resulting clo-th pieces was measured.
The relation between the concentration of slurry and the amount of' particles held in the glass cloth was deterrnined f'or each kind of the particles. ~'ig. 5 is a graph showing the results. The graph reveals that the arnount of each kind of particles increases with the increase of the slurry concentration.
Reference ExamPle 2 Diff'erent kinds of glass fiber products were caused to hold particles therein and checked for differences in the amount of the particles.
The same glasæ cloth as used in Reference Example 1 was used as a glass fiber product. Water was added to 200- to 500-rnesh magnesia particles to prepare a slurry havin~ a concentration of 25~ by weight. In the sarne manner as in Reference Example l, the glass cloth was caused -t,o hol(l magrlesia part,ic~es, an~l the ~mount of particlec held therein was meas~red.
The C,eme procedure ac, above was repeated with the exceo-tion oL using ~lass non~oven fabric, mat or roving cloth na-pped on one side ~by needling with 108 needles/cm2) instead of the glass cloth. The amount of magnesia particles held in each of the resulting glass fiber products was measured.
Table 1 shows the results.
rl'able 1 Glass fiber product Particles K d Weight* Amount Amount held/weight 1n (kg/m ) (kg/m3) of fiber product -~loth 1000 550 0.55 Nonwoven 600 520 0.87 Mat 80 650 8.1 Napped roving 470 620 1.32 cloth * Y~eight of product per apparent unit volume of the product.
** Weight of particles per apparent unit volume of the fiber product.
Example 1 ~he same glass cloth as used in Reference Example 1 was caused to hold magnesia particles in the same manner as in ~`~eference Exam~11e 2, and ~Nas then attached to -the opposite ~ides o~` a core o~ stainle~s steel pla-te, 35 mm x 50 mm x 1.5 mm, whereby a cat~lyst struc-~ure A of the sandwich type sho~n in l~'ig. 1 was prepared. Catalys-t structures B, C and D ~ere prepared in the same manner as above except tha-t glass lionwoven fabric, glass mat or glass roving cloth naped on one side was used for the particle holding layers in place of the glass cloth. The roving cloth, the same as -the one used in Reference Example 2, was attached to the steel plate with the napped surface inside.
Example 2 ~ lass nonwoven fabric, mat and cloth were caused to hold magnesia particles therein in -the same manner as in Reference Example 2. In the same manner as in Example 1, the glass nonwoven fabric was attached to a steel panel serving as -the core to provide particle holding layers therei)n. The glass cloth having magnesia particles held therein as above was placed over the holding layers to provide particle release preventing layers thereon, whereby a catalyst structure E of the ~ame construction as shown in Fig. 2 was prepared.
Further a catalyst structure F was prepared in the same manner a~ above except that the above glass mat having magnesia particles held therein was used in place of the glass nonllJo~en f`abrlc to nrovide particle holding layers.
'['~ble ,' shows thc thicknesses and weights of the layers lncluded in the catalyst s-tructures prepared in the foregoing exa~ples, and also the Qmounts of magnesia held ln -the layers.
Tab]e 2 Cata- Holding la~er Preventing ~yer Thick- Amount lyst ness of of` mag-struc- ~'iber Weight ~iber Weight layer* nesia ture product (g~m2) product (g/m2) (mm) (g/m2) A Cloth 200 - - 0.2 llO
Non-B woven 300 - - 5 260 fabric C hiat 400 - - 3 1900 ! Napped J
roving 570 - - 1.2 - 260 cloth Non-E woven 300 Cloth 200 0.8 380 fabric F ~lat 400 Cloth 200 3.1 1900 * The thickness of the particle holding layer or the combined thickness of the holding layer and the particle release preventing layer.
Reference Example 3 The catalyst structures A to ~` were tested for abra~ion resistance.
~ he catalyst structure A was fixed to the center of a 30-mesh metal screen having a diameter of 300 mm, 200 g of alumina ba'lls with a diame-ter of' 5 mm were -~laced into the screen, and the screen was vibrated on an automa-tic screening device (290 vibraiions/min ~ith an amplitude of 30 mm) f'or 4 hours. The amount of catalyst released was measured l hour, 2 hours and 4 hours af'ter the start of the vibration to determine the amount of' particles held in the struc-ture. The same p-rocedure as above was repeated for the catalyst structures B to P'.
Table 3 shows the results.
Table 3 Catalyst Amount of magnesia held (g/m ) structure Initial In 1 hour In 2 hours In 4 hours _ B 260 180 llO 40 1900 llO0 620 120 ~ able 3 reveals that all the structures have great ability to hold particles.
Reference Example 4 The catalyst structures A to F were tested f'or re~i~tance to vibrations.
l'he catalyst structure A was fixed to a 6-mesh metal ~creen and ~ubjected to vibrations for 2 hours by a 50-H~ vibrator mounted on the structure A. The amount of` particles released was measured 0.5 hour, 1 hour and 2 hours after the start of the vibration to determine the amount of particles held in the structure.
I~he same procedure as above was repeated for the catalyst structures ~ to ~. Table 4 shows the results.
Table 4 Catalyst Amount of magnesia held (g/m2~
structure Initial In 0.5 hour In 1 hour In 2 hours B 260 202 145 J~
C 1830 1620 1400 -~ 1250 Table 4 reveals that all the catalysb structures have high resistance to vibrations.
Example 3 A 300 g quantity of a-alumina particles not larger than 200 mesh in size were placed into a solution o~ 11.8 g of a~monium metavanadate, 3.8 g of ammonium molybdate tetrahydrate and 8 g of oxalic acid in 130 g ol water. 'l~he mixture was eva~orated to dryness wi-th stirring in a vacuum at a temperature of up to 60 C
and was iurther fired at 400 C for 3 hours. The fired product was pulverized to obtain 200- to 500-mesh catalyst particles, to which water was aclded to ~prepare a ~lurry having a concentration of 25~ by weight.
A strip of glass roving cloth napped on one side and having a thickness of 1.2 mm, wid-th of 20 mm and weight of 570 g/m2 was immersed in the slurry and pressed with rollers twice in the slurry. The strip thus impregnated with the slurry was fitted, with the nap inside, around a mild steel cylinder 18 mm in diameter and 80 mm in length and fastened thereto at its upper and lower portions. The strip was then dried at 100 ~ for 1 hour and thereafter fired at 400 C for 1 hour, whereby a columnar catalyst structure was prepared which had the construction shown in Fig. 3, with the roving cloth covering measuring 60 mm in length. The amount of particles held in the cloth layer was 240 g/m2.
Activit~ test ~ he columnar catalyst structure (having about 0.9 g of catalyst particles held therein) indicated at 22 and prepared in Example 3 was placed into a large-diameter portion 21, 23 mm in inside diameter, of a reactor of quartz as seen in ~ig. 6. The reactor was 1 ~55827 controlled to a predetermined reaction temper~lture. A
benzene-~ir gaseous mixture (with a benzene concentration o~ ~.8 to o.gqO) was led in~o the reactor throu~h a small-diameter portion 23 at a flow rate of 60 N~/h, and the resulting outflow was collected from the upper end of the large-diameter portion 21 to measure the amount of maleic anhydr~ide formed by the oxida~ion of benzene. The same procedure as above was repeated at vary1ng reaction temperatures. The same procedure as above was further repeated at varying reaction tempera-tures with thè exceptlon o~ using a benzene-air mixture having an increased benzene concentr~ation of 1.2 to 1.3%.
~or comparison, 0.9 g of 6- -to 8-mesh I a-alumina 300 grains were admixed with 9 g o~ - to 8-mesh ~ilica glass grains to obtain a catalyst ln the ~orm of~small pellets, which~was tested for activity under the same conditions as above. ~ig. 6 further shows a heater 24, a molten salt bath 25 and a the~rmo-couple 26.
Reactivities and selectivities were calculated ~rom the above measurements at each of the reaction temperatures acoording to the following equations.
Reactivity - (1 ~ Benzene cConncnn of ¢htargeW)x 100 I
1 1558~7 ~Mount Or maleic anhydride ~electivity = lor~med (mol/h) x lO0 Amount o~ benzene reac-ted (mol/h) The resul-ts are shown in l~'ig. 7, which reveals that the columnar catalyst structure of Example 3 is much more excellent than the pellet cat~lyst in both reactivity and selectivity.
Example 4 To a slurry composed of 30 parts by weight of anatase-type TiO2 particles not larger than 200 mesh and 70 parts by weight of water made acidic with sulfuric acid and having a pH of 2 to 3 was added ammonium meta-vanadate in an amount corresponding to 0.05 in atomicratio relative to the TiO2. The mixture was stirred at room temperature for 5 hours to dissolve -the ammonium metavanadate in the slurry and cause the TiO2 to adsorb the vanadate radical, affording a slurry of TiO2 retaining vanadium therein. Glass roving cloth weighing 300 g/m2 was immersed in the slurry and pressed with rollers twice in the slurry. ~he cloth thus impregnated with the ~lurry was attached to the opposite sides of a stainless steel plate, 50 mm x 29 mm x 0.3 mm, then dried at 150 C for 1 hour and thereafter fired at 400 C for 3 hour~, whereby a catalyst structure G of the sandwich type shown in Fig. l was prepared.
Cata~yst structures H to N were prepared in the same manner as above wi-th the exception of' using the glass fiber products shown in Table 5 in place o~ the glass roving cloth. The napped roving clo-th was used with the nap inside.
Table 5 ~atalyst Glass fiber productNumber ~ 2*
G Xoving cloth (300 ~/m ) O
H Napped roving cloth (300 g/m2) 162 I Napped roving cloth (300 g/m2) 216 J Roving cloth (570 g/m2) 0 K Napped roving cloth (570 g/m2~ 108 L Napped roving clo-th (570 g/m2) .J 216 1~ Nonwoven fabric, (300 g/m ) 1 0.8 mm in thickness N ~loth, 0.2-mm-thick (200 g/m2) * The number of needles used for napping.
Comparison Example One hundred parts by weight of TiO2 powder (not larger than 44 ~ in particle size, and 150 m2/g in ~urface area) and 100 parts by weight of colloidal silica (containing about 2010 by weight of SiO2) serving as a binder were thoroughly mixed together to obtain a slurry.
The slurry was applied to the opposite sides of 18-mesh metal net-ting (30 mm x 50 mm in size an(l macle of ~1rires, 0.5 mm in diameter, of SUS 304 steel), then dried et 100 C ~`or 1 hour and thereafter fired at 400 ~ for 3 hours, whereby a 'liO2 carrier was ~`ormed on the netting in the ~orm of a plate abou-t 0.8 mm in thickness. ri`he netting was immersed in a 2N oxalic acid solut~ion of ammonium metavanadate (1.0 mole/liter) at room temperature for 30 minutes, then withdrawn from the solution, there-after dried at 100 ~ for 1 hour and further fired at about 400 ~ for 3 hours, affording a catalyst 0 having the catalytic component suPported on the metal ne-tting.
Activity test Into a tubular stainless steel reactor 32 having a reactant gas flow channel 31, 6 mm x 30 mm, were placed three catalyst structures 33 as arranged in a row longitudinally of the channel and supported by metal nets 34 a~ shown in ~'ig. 7. A test reaction gas having the composition shown in Table 6 vras passed through the reactor 32 at a flow rate of13 N~/min to test the catalyst for activity to reduce N0 with NH3.
l'able ~
Component Proportion (by volume) N0 Abou-t 150 ppm NH3 About 150 ppm H20 10~/f C o 2 1 05o 2 5%
N2 Balance In this way, the catalyst struct~lres G to N
and catalyst 0 were te~ted for activity at va.rying reaction temperatures to calculate values K defined by:
K = -(AV) x ~n(l-x) l~
where: AV = ~'low rate of reaction gas (Nm3jh) Geometric surface area of cataly~t (m ) x - N0 reactivity 'The relation between K and the amount of TiO2 supported was established. Table 7 shows the results.
Table 7 t,atalystAmount of K
structureT .' 2 200 C 250 C 300 C 350 G 62 10.3 29.8 47.8 69.0 H 255 30.7 66.4 98.9 132 I 3t)5 32.1 ~7-9 100 137 J 7'0 10.9 28.2 41.4 54.1 K 362 35.1 67.0 103 141 L 361 36.7 73.4 122 172 120 17.5 42.2 70.0 99.5 N 65 9.8 24.9 36.2 47-3 0 400 12.3 26.3 40.9 49.4 Table 7 reveals that the catalyst structures G to N of Example 4 have higher K values per unit amount of TiO2 and higher activity than the catalyst 0 of ~omparison Example.
Claims (5)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. A catalyst structure comprising a shape retaining metal core having a desired shape, a catalyst particle holding layer attached to the core and made of a glass fiber product having a plurality of filament-to-filament interstices, and catalyst particles held in the interstices of the holding layer.
2. A catalyst structure as defined in claim 1 wherein the particle holding layer comprises a product selected from the group consisting of glass fiber nonwoven fabric, paper, mat, cloth and roving cloth.
3. A catalyst structure as defined in claim 1 wherein the particle holding layer comprises glass fiber roving cloth napped on its inner side.
4. A catalyst structure comprising a shape retaining metal core having a desired shape, a catalyst particle holding layer attached to the core and made of a glass fiber product having a relatively large number of filament-to-filament interstices, a catalyst particle release preventing layer attached to the outer side of the holding layer and made of a glass fiber product having a relatively small number of filament-to-filament interstices, and catalyst particles held in the interstices of the holding layer.
5. A catalyst structure as defined in claim 4 wherein the holding layer comprises a glass fiber product selected from the group consisting of glass nonwoven fabric, glass paper and glass mat, and the preventing layer comprises glass cloth.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000390256A CA1155827A (en) | 1981-11-17 | 1981-11-17 | Catalyst structure including glass fiber product |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CA000390256A CA1155827A (en) | 1981-11-17 | 1981-11-17 | Catalyst structure including glass fiber product |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1155827A true CA1155827A (en) | 1983-10-25 |
Family
ID=4121431
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000390256A Expired CA1155827A (en) | 1981-11-17 | 1981-11-17 | Catalyst structure including glass fiber product |
Country Status (1)
| Country | Link |
|---|---|
| CA (1) | CA1155827A (en) |
-
1981
- 1981-11-17 CA CA000390256A patent/CA1155827A/en not_active Expired
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1726698B1 (en) | Inorganic fiber aggregate, method for producing inorganic fiber aggregate, honeycomb structure and method for producing honeycomb structure | |
| EP1371406B1 (en) | Honeycomb structural body | |
| US3331787A (en) | Method of preparing an oxidation catalyst | |
| US4233183A (en) | Process for producing plate-shaped denitrating catalyst | |
| KR0150449B1 (en) | Attrition resistant catalyst support | |
| MX2007002990A (en) | Catalyst carrier substrate coated with washcoat comprising fibrous material. | |
| JP2003508216A (en) | Catalyst for selective oxidation of carbon monoxide and its production | |
| GB2026336A (en) | Plate-shaped denitrating catalysts | |
| AU761031B2 (en) | Exhaust emission control catalyst structure and device | |
| EP0375391A1 (en) | A catalyst for removing nitrogen oxides and a process for producing the same | |
| US7348289B2 (en) | Catalyst body | |
| US20040137194A1 (en) | Honeycomb structural, body, method of manufacturing the structural body, and method of measuring outer pepipheral distortion of the structural body | |
| CA1122584A (en) | Process for producing plate-shaped denitrating catalysts | |
| CA1155827A (en) | Catalyst structure including glass fiber product | |
| US4383941A (en) | Catalyst structure including glass fiber product | |
| DE3634360C2 (en) | ||
| GB2108860A (en) | Catalyst structure | |
| US4108218A (en) | Method of preparing a reaction chamber | |
| JPH0620559B2 (en) | Catalyst for catalytic combustion reaction and method for producing the same | |
| GB2193907A (en) | Ribbed catalyst bodies | |
| JPH0722709B2 (en) | Method for producing denitration catalyst using ceramics paper | |
| Sweeting et al. | Reticulated ceramics for catalyst support applications | |
| WO2020221891A1 (en) | Multi-functional catalysts for the oxidation of no, the oxidation of nh3 and the selective catalytic reduction of nox | |
| JP3104717B2 (en) | Production method of iron oxide catalyst for gas treatment | |
| JPS6121702B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |