AU606421B2 - Method for preparing a zeolite catalyst bound with a refractory oxide of low acidity - Google Patents

Description

17,259/88 PCT WORLD INTELLE ALROE RCNXT\0 INTERNATIONAL APPLICATION PUB LIsH6 0 Co ERATION TREATY (PCT) (51) International Patent Ciassification'4 Interna..onal Pubiicatlop Numnber', WO 88/ 08329 BOWl 29/04 Al 43) International Publication Date; 3 Novembc7 1988 (03.11.88) (21) International Application Ntimlor; PCT/UjS88/0 1446 (74) Agents; ROBERTS, Peter, William et at.; Mobil Oil Corporation, 3225 Gallows Road, Fairfax, VA 22037- (22) International Filing Dattes 2 May 1988 101 0)5.88) 001 (US).

(31) Priority ApplicatiVn Number; 044,639 (81) Designated States'. AT (European patent), AU, BE (European patent), DE (European patent), DK, FX (Eu- (32) Priority Date-, I May 1987 (01.05,87) ropean patent), GB (European patent), IT (Eutvpean patent), JP, NL (European patent), SE (European pa- (33) Priority Cou'try; US tent), (71) Appliz-ant; MOBIL OIL CORPORATION Published 150 L.ast 42nd Street, New York, NY 10017 With intgr,,ationqlsearch report.

(72) Inventors: A0I3SW Robert, Pete. P-311 I-teather Ridge Apartments, Mantua, NJ 0805! ANGEVINE, Ph IlipJa 713 Maegus D~rive, Woodbury, NJ 08096 (UjS). I-IERST, Joseph, Anthony 60 Bryant Road, JP. 5 JAN 1989 Turrsville, 14J 08012 McWILLIAMIS, John,...

Paul 117 South American Street, Woodbury, NJ ASRLA 08096

ASRLA

I -2 DEC 1988 I1lis 0tt11Wft v flt.4dP" thec 8 i,'imdni t i i I und PATC-NT OFFICE (54)T~tl; l~i~41 ,trd is corrit ibr (4Tlc METHOD FOR PREPARING A ZiiOITE CATALYST ROU ND) WVTI A Rf.FRACTORY OXID13, O 0~7) Abstract Itt a method for preparing a. low acidity refractory oxchi ml~tia 1co1it& ,afalyst, ther ks prc'vided a sbstartny homtogenous mixture of zcofite, watet and a lowv acidity refralctoryv oxidc bindcr Containing at, leas4t an etisopwtttn u ou f said hinder in a eolloid4t state to provido an emrdbl as teitutQ being substintially free of added aj koli met base and/o basi; s4l.14h extrudablc mass, is then exttrkidcd, drfied mnd Q4lcined, to vroduce a prodluct of similar crwsh strength. to an alumina-bound niatcrial, WO 88/08329 PCT/US88/0 1446 NfETHOD MR~ PREPARING A ZEOLITE CATALYST BOUND) WITH A RE1zACTORY OX1IDE OF LOW- ACIDITY BACKGROUND OF THE INVENTION This in vention relates to a method for preparing a mechanically stable zeolite catalyst CqMpoSition possessing a refractory oxide binder of low acidity, eqg,, a silica binder, The term "zoolite", as used herein. designates the class of porous crystalline silicateF,* which contain silicon and oxygen atoms as the major components, Other framework components can be present in minor amount, usually les$ than about 14 mole and preferably less than 40, These components include aluminum, gallium, Irgn, boron, etc,, and combinations thereof. The crystalline alumninosillcates constitute an especially well known type of Zeolite, It is well known that extrusion is one way of obt,,iAng a zeoiteCotating material which Wa a high degree of tent for various applications, betth Catalytic and non- catal~tic, i~s Some aluinnosilicate zeoliltes have long bee usd as ca'Ziyst for Pr wide variety of orgv- ni ronvorsion processes., In general, aluminoilicate Zeolltes are incorporated with a matrix, or binder, material In, order to impar't mechanical stability thereto, The most commonly used matrix materials 4 1i~qhave iveluded alumina and/or clays since these- materials are fairly easy to: extrude and provide extrudates of Food physical It has long been. recognized that Sil~kca is a desirable matrix and that it possesses advantages over alumina for ,some Catalytic reactions# In this connection, Patent No.

4,013,732 5p ,Qitfcally discloses, Z$M-5 with a silica matrix and U.S. Pat~in Nos* ,84.1, "41 and 3,102,06 broadly disclose the use of 1W q-5 with. a silica matrix.

L.

WO 88/08329 WO 8/0329PCT/CS88/ 01446 -2- U.S. Patent No. 4,582,8.15 describes a method for preparing silica-rich solids said to possess improved crush strength compared to that of known silica-bound materiaL. The method comprises mixing sillca-rich solids, preferably a mixture of silica with a zeolite such as ZSM-4 (Omega), ZSM-ll, ZSM-l2, ZSM-23t ZSM-35, 4 $M-38, ZSM-48, Beta, X, Y, Lt ferrierite, mordenite, dachiardite, clinoptilolite, offretite, erionite, gmelinite or chabazito with water and ain alkali metal base such as sodium hydroxide or a basic salt suc~i as an alkali-metal carbonate, borate, phosphate or silicate as an extrusion aid followed by mulling, extruding and subsequently dr'ying the extrudate, It is thought that substitution of alkali metal for hydrogen in the silanol groups on the surfaces of siliceous materials such as the foregoinog zeolites is responsible for their improved crush strength, The resulting 6xrrudate Is said to possess superior crush strength and iuf ficient integrity to withistand treatments with acids so that it is possible to steam, acid extract or calcine them, To avoid trapping the alk~ali metal of~ the extrusion aid in the extrudato, the alkali metal is ordinarily removed by exchange under acidl.- conditions using dilute nitric acid in. D1 ammonium nitrate solution, Silica-bound ;eolite cata %Ysts prepared in accordance with the method described In O'aent No. 4,58Z*,l5 are indicated to be useful In hydrocarbon cornvorsi ,ns such as hydrocracking, lsomeritlont hydrogenation, dehydrogenuation, polynerizationj re~orming, catalytic cracking and catalytic hydrocracking.

It has now been discovered that a low acidlity tefractory oxIde'-bound Zoolite possosslng excellent mechanical stability and low binder acidity, mak~ng it especially useful as a catalyst for certain kinds of hydrocarbon cnrlos can be prepared by a method which comprlsest WO 88/08329 WO 8808329PCT/US88/01446 3 a) providing a substantially homogeneous mixture of zeolite, water and a low acidity refractory oxide binder containi~ig at least an extrusion-facilitating amount of said binder in a colloidal state to :.ovide an extrudable mass, said mixture being substantially of added alkali metal base and/or basic salt; b' extruding the extrudable mass resultinS from step c) drying the extrudate resulting from step and d) calcining the dried extrudate resulting from step The calcined extrudate can be subjected to other operations such as base exchange, dealumination, steaming and impregnating with catalytically active metal(s), the details of whi-h are well known in the art, Unlike alumina binders, low acidity refractory oxide binders such as silica do not interact with zoolites to any appreciable extent. Consequently, 6-elltes can bo bound with low acidity refractory oxides In accordance with the method of this invention without increasing the zeolite's intrinsic jctivity as might occur with an alumina binder In some types of hydrocarbon onversions, eg., hydroprocesstng, reforming, catalytic cracking and catalytic hydrocracking, the use of low-acidity refractory oxido-boupid zeolltes having lower levels of inherept activity than their alumina-bound counterparts can result In lower coke production and significant increases in cycle length, On the czontriry, the zeolito's intrinsic catalytic activy may actually be decreased by binding the zeolite with low acidity r-_fractory oxides, such as silica. More particularly, zeo~ite activity may be reduced by binding zeolites such as ZSM-S, Yo beta, etc.

with low acidity refractory oxides such as $ioz and V014~ It is believed that this reduction in, activity is a result of a chemical reaction of the binder with the o:oolitot whereby high

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WO 88/08329 PCT/US88/01446 -4acidity oxides such as alumina in the zeolite framework become replaced by low acidity rofractory oxides from, the binder. For example, zeol? te* with a silica to alumina molar ratio 70 or less may become enriched with framework silicon content by binding the zeolite w'ith silica and treating ttie mixture at elevated temperatures, Zeolites treated in this manner may exhibit lower exchaange capacities, hexanle cracking as measured by alpha value) and toluene disprQportionation activities, and shifts in x-ray diffraction patterns.

When employed in a low pressure hydrocracking

(LPHC)

process, a silica-bound, low sodium, framework dealuminated zeolite ultrastable 'I (USY) zeolite, has been found to provide signiificantly better results than a comparable alumina-bound USY z-'olite.

Since the low~ acidity refractory oxide-bound zeolite catalysts of the present invention are capable of maintaining their structural in-cegrlty in low pR solt ln, ti-eolt dispersed in such a blader can be tr,.ated with an acid solution to effect dealumination. 'This effectively results in a reduction in manufacturing costs of low acidity zeolite, catalysts since extrudates are easier to handle than powders, The method of this Invention is not limited to any particular zolte and in general May be employed with all $ta I~licates, particularly the aluminosilicates whether or 23 not previously dealuminated to increase the framework sillca~aiumina ratio, Typical Zeolites Include ZSM&4 (Omega), ZSN4-St ZSM-1l, ZSM-1614 ZSN-2, ZSM-23, "SM-35, Z$M-8, Z$SS, ,ttX, Y and L~ as well as erierite, aiozdcaitdhidt, clinoptilltt offrotlte, erioaitet gmollnlte and Qhabazite.

The original. catlor~ ssoii with each of the Zeolites utilizod herein can be replaced by a wide variety of other cations employing techniques well knowit in the art, Typical replncirg cations including hydroniumt, ammoniums alkyl amnmonium, anel metal cations., Sui.-Kbe metal cations include WO 88/08329 WO 8808329PCT/US88/O 1446 metals such as rare earth metals, as well as metals of Groups IIA and B of* the Periodic Table, zinc, and Group V111 of the Periodic Table, e, g. platinum and palladium, Typical ion-exchange techniques call for contacting the selected zeolite with a salt of the desired replacing cation. Although a wide variety of salts call be employed, particular preference is given to chlorides, nitrates and.

sulfa tes. Representative io;'t-exchange techniques are disclosed in a wide- variety of patents including U.S. Patent Nos, 3,140,249; 3,140t251; and 3,140,25.3, Following contact with a solution of the desired replacing ciaxon, the zeolite is then preferably washed with water andt dried at a temperature of 0,5-3150C (l50-600"F) and thereafter calcined In air, ,or other inert gas, at a temperature of ZO-8150C (500-1500"F) for I to 48 hours or more. Catalysts of improved selectivity and other beneficial properties can be obtained by subjecting, the ;eolite to treatment with steam at elevated temperatures ranging from 260 to 650 0 C ($00 to 1200 0 F) and preferably from 400 to $40 0 C (750 to 100011T)., The treatment can be accomplished in an atmosphere of 100% steam, or In An atmosphere consisting of steam or ammonia and some other gas which is essentially inert to the zeolites. A similar treatment can be accomplished at low~er temperatures and elevated pressure, from 180 to 370 0

C

(3509 to~ about 701F) at fr(rn 1000-20000G kPa (10 to '100 atmospheres), If so desired, the 4"eolite can be treated wi th reagents prilor to steaming and with organics still contalIed from synithesia to remove alumina from the outside surface, or calcined ia air or Inert atmosphere to remove the organics and then ion exchanged to the ammoniunt form or other desired metal exchanged form tt is a special attribute of the low acidity refractory oxide-bound teolite extrudata herein that it has sueflcieint Integrity to withstand treatment with acids, so that WO 88/08329 PCT/US88/0 1446 -6it is possible to extrude an aluininosilicate zeolite such as zeolite Y and steam, acid extract, calcine or effect combinations thereof to produce a stable high silica-to-alumina Y in an easily handled form. Processes for deal uminiz La., Y a~e well known in the art, see Rabo, Zeolite Chem~istry anC,- Catalysis, AC$ Monograph 171(1976) Chapter 4.

The binder material used herein can be select' d from among any of the low acidity refractory oxides of metals of Groups IVA and IVB of the Periodic Table of the Elements.

Particular-ly useful are thcQ oxides of silicon, germanium, titanium and zirconlium~ with silica being especially preferred.

Combinations of such oxides with other oxides are also usef\il provided that at least about 40 weight percent$ and preferaoly at least 50 weight percent, of the total oxide is one or a combination of the aforesaid Group IVA and/or Group IVB metal oxides. Thus, mixtures of oxides which can be used to provide the binder material herein include silica-alumina silica-magnesia, sllica-zirconia, silica-thoria, silica-berylliaf silica-titania, titania,;irconia, silica-aluinn-thoria, 5111ca-41umina- zirconla, silica-alumina-magnesia, and silica-magnesia-Zirconia.

It is an important requirement of the method of the invention herein that the low acidity refractory oxide contains at least an eXtruslon-faCilitating amount of the oxide in colloidal forni, preferably with water as t.he dispersant4 In general, however, at least part Qf tito low acidity refractory oxide is added In dry particulate form$ eq. amorphous precipitated silica, s0 as to control the moisture content of the blnder/zeolite/water Mixture at a level to ensure satisfactory extrusion, Preferably the moisture Conltent of -the mixtturo does not exceed 50%* and preferably Is at least 40%s by wO.Xht., No alkali metal base or basic Salt is added to the mixture 4 WO 88/08329 PCT/US88/Gi446 7 The colloidal Group IVA and or Group IVB metal oxide component of the binder can represent anywhere from 1 to weight percent or more of the total binder. For example, in the case of silica, amounts of colloidal silica ranging from 2 to 60 weight percent, preferably 5 to 50 weight percent, of the total binder generally provide entirely acceptable results.

The relative proportions of zeolite and low acidity refractory oxide binder can vary widely, with the zeolite content ranging from between 1 to 99 weight percent, and more usually in the range of from 4 to 90 weight percent, of the total extrudate (dry basis).

Extrudates of 1/16 inch (1.6mm) obtained in accordance with this invention typically have a crush strength of from to 24 pounds (2 llkg) when the crushing force is applied over a 1/8 inch (3.2mm) length. This is equivalent to a crush strength range of 40 to 192 Ib/linear inch (700 3430kg/m).

In addition, the low acidity refractory oxide-bound extrudates of this invention are also characterized by a high porosity, between 0.43 to 1 cc/gram (measured by mercury porosimeter and helium absorption), The extrudates of this invention can find utility in a wide variety of processes which are both catalytic and noncatalytic. Quite obviously, the materials can be used as sorbents, Additionally, the materials can be used as catalysts for a wide variety of organic conversions. Moreover, since a low acidit, refractory oxide, such as silica, has low catalytic activity, the incorporation of a zeolite in the silica can lead to some unusual catalytic effects. The low acidity refractory oxide can also be used as a support for a catalytic material, a hydrogena.ion component such as platinum, palladium, cobalt, molybdenum, iron, tungsten, nickel or mixtures of the same. The catalytic metals in the form ot their oxides or salts can also be added to the low acidity refractory oxide during the mulling step with pH adjustment, if necessary, to t, L WO 88/08329 WO 8808329PCT/US88/0 1446 8 stabilize the colloidal oxide component of the mixture. In particular, the low acidity refractory oxide-bound zeolite extrudates of the invention find utility in catalytic cracking, typically under conditions including a temperature of at least 315 0 C (6000F), generally 400-6000W (7500-11000F), and pressures between 100 and 1500 kPa (atmospheric and 200 psig).

If desired, the cracking can be conducted in the presence of hydrogen, preferably with the hydrogen partial pressure being no greater than 7000 kPa, The invention will now be more particularly described with reference to the Examples, in which all parts are by welgh'. unless otherwise specified, txample, I (Comparative) This example illustrates the preparation of an is alumina-bound USY catalyst to provide a basis for comparison -4tth silica-bound USY catalysts prepared in accordance with the method of this invention (Eixamples On a dry basis, weight parts of U, ;:eoite (Z-14US, W.R. Grace) were intimately admixed wiith S5 weight parts finiely divided alpha alumina monohydrate (Kaiser and an extrudable mass Was obtained by mulling. The moisture :ontent of the mix was adJusted to 46-48 weight percent by addition of delonlzed water# After additional mling, the resulting paste was extruded using a 211 (5cm) lDonnot extruder to yield 1/16"1 (l.6inm) diameter extrudates, The extrudates were subsequently dried at 121 0 C (Z50"F) for 1$ hours In air and then calcined at $400C (10004F) for 3 hours in air flowing at 3 or v/v/mm,. Heating rates of 2 or 3OC/min 0~ or SOP/mitt) were used, WO 88/08329 PCT/US88/01446 9 Examples 2-6 parts of USY powder were mixed with 35 parts of (dry basis) of silica consisting of various ratios of an amorphous precipitated silica (PPG Industries HiSil 233 EP) and colloidal silica and were mulled to produce an homogeneous mix. The moisture content of each mix was adjusted to 42-47 weight percent with deionized water. Each mix was extruded using a 2" (5 cm) Bonnot extruder and the extrudate treated substantially the same as described in Example 1. Since the alpha activity of the bound USY extrudate (as measured by the alpha test) was less than 10, the extrudate was ammonium exchanged to remove sodium employing a three step ammonium exchange/calcination procedure. After ammonium exchanging at room temperature for 1 hour with 5 ml/g circulating IN ammonium nitrate, the extrudate was washed and dried at lZlC (2500F) in air and subsequently calcined at 540oC (10001F) for 3 hours in dry flowing air, This procedure was repeated three times so that the acidity of 'the catalyst (as measured by the alpha test) increased to a level of 2S0 to 300 and the sodium content was reduced from l,8-l.9 to 041-0,2 wt The calcinations were performed in a relatively anhydrous environment to preclude any significant steaming of the catalyst, In these Examples, the effect of colloidal silica content on the physical properties of the Zeolite was evaluated by varying the amount of colloidal silica in the extrusion mix from 175 weight percent to 2.2 weight percent (on a dry basis). Additional amorphous precipitated silica was added to maintain a 6S/3S zeollte/binder weight ratio (on a dry basis), The physical properties of the alumina and silica bound catalysts of Examples 1-6 are set forth in Table 1, While two commercial sources o£ colloidal silica were used, a clear correlation was observed between crush strength and colloidal silica content demonstrating the critical role of colloidal silica as a binding agent.

TABLE 1 c Yroperties of Bound USY Catalysts 0 00 jExample, 1 2 3 4 5 6 IWt, I Amorphocus precipitated Silica '0.0 17.5 26.2 30.6 30.6 32.8 WI Colloidal Silica 0.0 17.5 8.8 4.4 4.4 2.2 Colloidal Silica Source (Alumina- EM1 1 EM Ludox, Ludox, bound) Science Science Science IIS-30 Scdium cntent, ppm 870 1170 f4S 1580 ]580 1650 Alrha Activity 300 266 255 279 321 263 Unit Cell Size-, Angstrox!s 24,52 24.51 24.52 ND 24.61 24.56 fLensity., g/cc Real 2.735 2.38 2.35 2.32 2.35 2.33 Particle 0.94 0.89 0.10 0.84 0,84 0.84 Surface Area, 1Wf2 g 476 439 4 09 434 413 430 PoCre Volum~e, cc/g 0.00.70 0.68 0.68 0.76 0.77 Avp. Pore LDiameter, A 59 64 67 63 74 71 P$D. I of Pores Uith 0-3D A Uia: er 316 33 33 32 33 27 30-50 7 4 3 2 1 2 50-80 10 4 4 4 3 3 80-100 6 4 3 3 22 100-150 9 8 7 7 200-300O 2 9T 13 15 15 35+2 7 32 29 28 33 39 Crush Strength (lIb/in) '5 84 77 71 87 53 E (gr)1161 1500 1375 1268 1554 946 -0 WO 88/08329 PCT/LrS88/01* 46 EXAPLES 7-9 Weight percent zeolite beta (on a dry basis) in the form of a powder was mulled with 35 wt parts of combined aL 1 orphous precipitated silica (Hisil 233 EP) and colloidal silica to produce a homogeneous mixc, To facilitate Admixture, the moisture content of the mix was adjusted to, 45-49 Weight percent by Adjusting the amount of detonized 1'ater added, Two different amounts of colloidal S10 2 were added to obtain extrudable mixes while maintaining a 65/3$ zeolit/bne Weight ratio, The resulting mixs were extruded to yield 1,6MM (1/16"1) diameter extrudates! The eXtrudates were dried at !21"C (250 0 F) for 18 hours and were- subsequently calcined4 At 540 0 C (l0001-F) for 4 hours iii nitrogen flowing at 3 or v/v/min, This was followed by a 3 hour calcination at 1Q00OF ($400C) In air flowing at 3 or 5 v/v/min. Ne. t, each extrudste 1$ was exchanged twice at room temperature for 1I hour witha$ ind/g circulating IN amnmonium nitrate solution. After washing the eXtruda1te was then Calcined at $400C (l0001T) for 3 hours in air f 12Ovng at 3 or 5 V/v/min, F or purposes of cor'Warisoni, the physical properties zo of the foregoing8 extrudate (Examples R And 9) were Comipared With those of a Commercially available a L i boun -eolite beta (Examiple 7), The physical property datx are set forth in CTabe as fqllows: i I WO M(108329 PCT/US88/ 1446 12 TABLE 2 Physical Properties Of bound Example 7 Wt$ Amorphous Precipitated silica 0 Wt.% Colloidal Silica 0 Moisture Content, Sodium Contento ppm ND Alpha Activity US, 1Q 0ensity, g/cc Packed O Real 2,S$ Particle 09 SurEace Are4. m2/g 480 Pore Volume, cg ,74 Avg. Por'e Diameter. Anpgt'ms 61 Crush Strqngth kg/i lb/i154 ND 4 n ot determined Beta Catalysts 8 17.5 17,$ 45o7 765 344

NM

2,3 421 0. 71 6a 13f 6 261.

8.$ 342 0.52 2.34 0. $2Z 0,' 74) The E'wvegoing data clearly show the eEects of the colloidal silica as binding agent. Theo physical properties of ~lfica:b ac~iud zeolitv beta catays t are sitiilr to those o the alumina-bound zeolite Beta, WO 88/08329 WO 8808329PCT/US88/O 1446 13 Examples 10 to 12 $M4ica-bound ZSM-S extrisdates (Examples 11 and 12) were prepared substvatia11y os described in Examples 8 and 9.

The physical properties of the riljoa-bound ZSI4-5 extrudates and those of a commjercial aluminaboxid ZISM-5 extrudate (Example 10) ore set forth, in Table 3 as follows: TABLE 3, Physical Properties of Bound Zsm-s Amnorphous precipitated silica VJ Wt, 1, Colloidal Silica Sodium Con'ceatt ppm Alpha Activity hcsi~y 8/co pa fle Sjurfau Area, 4)2/g Pore Vtolume, cc/g Avg. Porce fl me e Angsttoms L' q Crtwih Strergth i*g/ma (I'/4nch) Catalysts 11 17.5, 17,$S 81 about 220, 0.91 0 96 84 85 NI) 1143(64) 2 ~31 0. $7 287 ~X 72 101 ND*not determinowd WO 88/08329 WO 8/0329PCT/US88/01446 14 Examples 13 17 Previous. examples demonstrate that silica-bound catalysts prepared by the extrusion method of this invention retain their structural integrity upon calcination and amimonium exchange. An important advantage of silica-bound zeolite catalysts is that the oxtrudatcs can be acid treated without losing their structural i-tegrity, Thus, the silica-bound USY catalyst of Example 3 was steamed for 10 hours at 540 0

C

(l0000F) to reduce the alpha activity from 253 to 50-60 and to reduce the unit cell size from 24.52 to 24.35 Angstromns. The steamed extrtqate (4xample 13) was then treated for 4 hours in a 1N HNO3 sollutIon at $SoC or 85oC (Examples 14-17), As a result of the acid treatment, the alpha activity was reduced to 6 and 'the unit cell size was reduced to 24.25 Angstroms as detorm'Mowd by x-Aynal~ysis,, Good crystallinity was retained (greocer than about 50%1), More Importantlys however, equivalent crush strengths were obtained before and after steaming an Wi treatment. The data are surnetrized in Table 4 as follows;, TABLE 4 Physical Propert4ies of Acid Treated Si02-Bound lISY Catalysts Example 3 13 16 17 11N03 4concentration Treztment Temp., oC Treatment

T

ime, lirs.

ml of !&3gCat-.

Dkilt Cell Size, A Crystallinity, 1, Alpha Activity Crush Strength, lb/in (kglm}) Na, wt% Sim2, 'Wt A1203. wt%1 Ash, wtt Surface Area, *2/g NMD not determined IN, IN' IN IN IN IN 55 55 -4 4 -5 "a 24.52

ND

,255 77 1375 (83.3) (13.6) (97.6) 24 .36 65

,ND

0.11 S3.3 13.6 97.6 24-30 65 76

ND

ND

0.05

ND

-ND

24.27

ND

6 81 1140 0.01 97-2 .2.8 98.9 24.35 60 83

ND

,ND

0.04 95.4 6.:6 98.7 24.26 55 6 74 1321 0.01 97.2 2.1 98.9 24.25 55 6 82 1464 0.05 '97.2 2.3 ,98.7 24.28 56 11000 0.98 97. 1 2.2 ,98.9 409 482 480 488 WO 88/08329 PCT/US88/01446 16 Example 18 A sodium exchanged zeolite Y (NaY) was extruded with silica in a 65/35 zeolite binder ratio. This extrudate was prepared by mixing, on a dry basis, 65 weight parts of NaY with 17.5 weight parts amorphous precipitated silica (HiSil 233 EP) and 17,5 weight parts of colloidal silica (HS-30). After mulling and water addition as appropriate, the resulting homognious mixture paste was extruded to 1/16" diameter extrudate. The extrudate was dried at 121'C. 1 gram of this catalyst was calcined 4c 5380C for four hours under high nitrogen purge such that in-situ steaming of the material was avoided. The calcined silica bound catalyst was analyzed by x-ray diffraction along with the uncalcined silica bound catalyst.

X-ray diffraction data was collected at the Brookhaven National Laboratory, National Synchrotron Light Source on the X13A powder diffractometer. The diffractometer employs parallel beam geometry with a Ge(li) incident beam monochromater and a Ge(220) analyzer crystal, rata was obtained with a 2-theta step scan of 0,01 degrees, 2 second count t1mos per step, a theta scan of 2 degrees per step, and an x-ray wavelength of 1,3208 Angstroms. The 2-theta zero and x-ray wavelength were calibrated with a National Bureau of Standards silicon metal standard, D-spacings were obtained from the measured data wit a second derivative peak search algorithm. The lattice parameters were refined with a standard least-squares refinement program.

For both samples, the expected orthorhombic unit cells were obtained, The a 0 values obtained as well as the calculated estimated standard deviations (esd) were: ao esd Uncalcined Catalyst 24.6611 0,0005 Calcined Ctalyst 24.56a 0,0006 WO 88/08329 PCT/US88/01446 17 The difference between the two a values is 0.0043 whereas the sigma 1, calculated from the esd's, equals 0.0008. On statistical grounds, the limit of significance between the two unit cells is 5.51 sigma. From a normal distribution chart, at significance levels of greater than 3.89 sigma the probability is less than 0.0001 that two equal unit cells would be found to differ to by 0.0043 Angstroms. This establishes the level of confidence at greater than 99.9999% that the two unit cells are statistically different. The calcined silica extrudate shows the unit cell contraction consistent with silica Lssertion itLo the framework of the zeolite in place of framework alumiria.

Exarnle 19 (Comparative) To show the importance of controlling the moisture content of the extrudable mass, a zeolite beta/silica mix was prepared with a 05/355 weight ratio as in examples 8 and 9 but using only colloidal silica as the low acidity, refractory oxide source.

Thus, to 397.3g tf zeolite beta crystals (ash content 75,5%), 538.5g of colloidal silica (Ludox HS-30) were gradually added and mulled, However, the resulting paste was too wet (moisture content 50.4 to be extruded.

Example The process of Example 19 was repeated but with ratio of the zeolite beta (ash content 75,5%) to colloidal silica (ash content 30%) increased to 82.5/17,5 to produce mixtures in which the moisture content was at a level suitable for extrusion, The results are shown in Table S below: r.- WrO 88/08329 18 PCT/US88/01446 'fable S Physical Properties of Silica-Bound Zeolite Beta Zeolite content, wt.% Silica content (Bi~il), wt.% Silica content (Ludoxc), wt.% 82.5 moisture content (actual), wt.% 46.5 Solids content (actual), wt.t 53.5 Solids conteit (target), wt.% 53.0 Crush strength, ib I/inch 68 kg/n 1,Ul4 flensity, g/cc Particle 0.89 Real 2.34 Sur~face area, m2~/g 513 Pore volume, cc/g- 0,70 1 Estimated from target moisture content, 44.61 55.41 55.0 76 1357 0.91 2,34 503 0.67 43.6 56.*4 56.0 0.92 2.*36 $08 o0.67 L

Claims (5)

1. 6. Theo mntjhed of Claimn 4 wherein the contenL o)f rsiliCa (dry basis) frOlla Colloidal silica roproesentsl from. to 50O Weight pe(rcent of the totalj binder., 7, The method of Claim 1 wherein th10 moisture, content of the oxtrudable maass lis4O~~ welit* I i r)
2. 8. The method of Claim I wherein the zeolito content (dry basis,1 represents from I. to 99 weight percent of the total extrudate.
3. 9. The method of Claim 1 wherein the zeolitk,,' content (dry basis) represents from 40 to 90 weight percent of the total extrudate, A method substantially as hereinbefore described with reference tQ any one of Examples 2 to 6, 8 to 9 or 11 to 12, MOI OI COPCAIN D t. So* 61 il' #$sip DAsootovmer19 PHLLIP ORONDE& FTZPARIC INTERNATIONAL SEARCH REPORT International Application NoP CT US 88/0 14 4 6 1. CLASSIFICATION OF SUBJECT MATTER (if several classification Symbols apply, Indicate all)I Aqcorln :g to International Patent Classification (IPC) or to bothv National Classification and IPC IPC BOIJ, 29/04; U q. CT, 502 64
4. 11. FIELDS SEARCHED Minimum Docujmentation Searched Classif~cation System IClassification Symbitols U'S. 502/64 Documenitation 5earched other than Minimum Documentationt to the Extent, that such Documents are Included in the FieldsS earched I.DOCU MNTS CONSIDERED TO BE RELEVANT -I Category Ii Citation of Documenit, 11-Nith indication. wherea ppropriate, of the relevant passage$ 177 Relevant to Claim No. ka US A, 4,562,815 15o~s) AVVdil M'6 1-10 TJS,A, 3,518$,Z06 ($ovirds et at) 30 Juno (Se.e aolamrn 4* lines 31-5$0) t970 1-10 "A't doumyenit dafirij Ite general stateso t e Aft otilon is niot Oqfl~tdJe1@q fa~ ll of 04(iivylo relevance Selild otuiont l t 044J4 oft d' 0 ltr lhq iliferrnationof 11 ,dd~tifflenf whiCh, MA~f throw dauil* Of itidtity 01Alnit Of Whidri is 01110d t4 Oitl~lisrn the Ojtiartr dalet Of OnothOr Clatildi of other special 1545041 Oifleejf '00" documlent 0ollothng to d 4n l diqilytil, ulio ilihubflit di ills" doqqumefif pijbliill prior to the itltenipoil~f flit daIS but laidf thlan the P1i0rity 1310q fctailfl lf doicument otibi 'hodi After the intenaILOnaflin t;1tea of Wiioitiy date AnA Mnot in dolifliC W:Illn trio D~lclo ut cited to u41dar*tai d the oh Ploil of theoty unflitnl toe nventlijr 'X1 docunieif of .Articitar rqleqrjila the clajilej nventlon Cannot no cOnill5ede nivel 0 5Oflf n b e OQnjiieqj to in1volve anl inlventive *10 dodCUnlent of particular' WOVe0iiO, the ctAlMe4i invoiltoi cannot De onqidered t:1 iniyolvit An, lily4iltve lt4 wheni thI dcoCumen-t 14 Combo~ie with One (it more othar SuCh d0o(u, MentS1L ijh Corin'tion10 bei01 OviouS to a plitS01 SltisO it the n m e b r It e atPa e t141 1 IV, WiFi'$PlCATION
5. 041. of theS Alu4il C~rolstion of tho IntertliQnal 5#11t ri 1 Oate of Ma tij of this trlnatatinl 51.44j Rqp~ft t 0 7. q A 0JUN 1988 Intt~o~aiisewl L~ht~li ignAtijf of Autl~iled Oltice0 t eli, /U 4A Ir ow r PtqT I$ A210 1it C o rd S h 4 t II M aY 19 0 81