Title of Invention

A PROCESS FOR PREPARING ZEOLITE ZSM-11

Abstract

A process for preparing the zeolite ZSM-II which comprises: (a) preparing an aqueous solution comprising sources of (I) an alkali metal oxide, alkaline earth metal oxide or mixtures thereof; (2) an oxide selected from the oxides of alum inum, boron, iron, gallium, indium, titanium, or mixtures thereof; (3) an oxide selected from oxides of silicon, germ anium or mixtures thereof; and (4) at least one 3,5-dimethylpiperidinium compound as a templating agent, (b) maintaining the aqueous solution under conditions sufficient to form crystals of ZSM-ll; and (c) recovering the crystals of ZSM-1l.

Full Text

GOVERNMENT OF INDIA, THE PATENT OFFICE 2nd M.S.O. BUILDING, 234/4, ACHARYA JAGADISH CHANDRA BOSE ROAD KOLKATTA - 700 020. COMPLETE SPECIFICATION NO. DATED:. 14-Feb-95 APPUATION NO. 170 MAS 95 DATED: 14-Feb-95 ACCEPTANCE OF THE COMPLETE SPECIFICATION ADVERTISED ON INDEX AT ACCEPTANCE — 39 O INTERNATIONAL CLASSIFICATION ^ C O 1 B 33 / 28 TITLE : " A PROCESS FOR PREPARAING ZEOLITE ZSM-11" APPLICANT : CHEVRON U.S.A. inc 555 MARKET STREET, SAN FRANCISCO, CALIFORNIA P.O.BOX 7141 SAN FRANCISCO CA 94120-7141, USA. a corporation duly organized under the laws of the state of Pennsylvania. INVENTORS 1 .YUMI NAKAGAWA. THE FOLLOWING SPECIFICATION PARTICULARLY DESCIRBES AND ASCERTAINS THE NATURE OF THIS INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED: - The present invention relates to a process for preparing zeolite ZSM-U using a templating agent comprising at least one 3,5-dimethylpiperidiniuni (3,5-DMP) compound, and to zeolite ZSM-11 in pure phase form. Zeolite ZSM-11 and methods for making it are known. For example, U.S. Patent No. 3,709,979, issued January 9, 1973 to Chu, discloses the preparation of ZSM-11 using quaternary cations of a Group S-A element, such as ammonium and phosphonium compounds, as the organic templating agent. It does not, however, disclose the 3,5-DMP compounds of this invention as templating agents. U.S. Patent No. 3,709,979 is incorporated herein by reference in its entirety. U.S. Patent No. 4,108,881, issued August 22,1978 to Rolhnan et al., teaches the synthesis of ZSM-11 using C7 and C12 alkylenediamines as the organic templating agent. U.S. Patent No. 4,894,212, issued January 16, 1990 to McWilliams et al., discloses a method for synthesizing ZSM-U using octylamine as the organic templating agent. U.S. Patent No. 4,941,963, issued July 17, 1990 to Valyocsik, discloses a method for synthesizing ZSM-11 from a reaction mixture containing a diquaternary ammonium templatmg agent. It is alleged that pure ZSM-11 has been synthesized using tetrabutylphosphonivmt, tetrabutylammonitrai and 1,8-diaminooctane (Cg) and 1,9-diaminononane (C,) . See P. A. Jacobs and J. A. Martens, Studies in Surface Science and Catalysis, 33, p. 147-166. Lok et al., in Zeolites, 3, 282-291 (1983), disclose numerous compounds which act as templating agents for the synthesis of various crystalline materials, including ZSM- 11. This article does not, however, disclose the organic templating agent of the present invention for the synthesis of ZSM-11. U.S. Patent No. 5,213,786, issued May 25, 1993 to Beck et al., discloses the synthesis of ZSM-11 using a trimethyl ammonium cation having the formula CnN+CH3)3 where n is 9, 10, 11, or 12 as the organic templating agent. These trimethylammonium compounds are said to supply the proper pore-filling and charge density balance to produce ZSM-11 at the expense of ZSM-5. It has now-been found that ZSM-11 can be prepared using 3,5-DMP compounds as the templating agent and that the resulting ZSM-11 product is in pure phase form. Accordingly, the present invention therefore provides a process for preparing the zeolite ZSM-11 which comprises: (a) preparing an aqueous solution comprising sources of (1) an alkali metal oxide, alkaline earth metal oxide or mixtures thereof; (2) an oxide selected from the oxides of aluminum, boron, iron, gallium, indium, titanium, or mixtures thereof; (3) an oxide selected from oxides of silicon, germanium or mixtures thereof; and (4) at least one 3,5-dimethylpiperidinium compound as a templating agent having the general formula wherein R1and R2independently represent an alkyl group, either branched orunbranched, substituted or unsubstituted, containing from 1 to 7 carbon atoms, with the proviso that R1and R2are not both methyl, or R1and R2together comprise a cyclic alkyl ring system, which, including the positively charged nitrogen atom, contains from 4 to 7 atoms, said ring system being unsubstituted or substituted with branched or unbranched alkyl groups, and X is an anion which is not detrimental to the formation of the ZSM-11; said aqueous solution comprises, in terms of mole ratios, the following: YO2/W2O3 15 and greater OH7Y02 0.1-0.6 Q/YO2 0.01-0.50 M*/Y02 0.01-0.50 H2O/YO2 15-100 Where Y is silicon, germanium or mixtures thereof; W is aluminum, boron, iron, gallium, indium, titanium or mixtures thereof; Q is a 3,5-dimethylpiperidinium compound; and M is an alkali metal, alkaline earth metal or mixtures thereof (b)maintaining the aqueous solution under conditions sufficient to form crystals of ZSM-11; and (c) recovering the crystals of ZSM-11. The present invention also provides this process further comprising replacing alkali and/or alkaline earth metal cations of the recovered ZSM-11, at least in part, by ion exchange with a cation or mixture of cations selected from the group consisting of hydrogen and hydrogen precursors, rare earth metals, and metals from Groups IIA, IIIA, IVA, IB, IIB, IIIB, IVB, VIB, and VIII of the Periodic Table of Elements. The present invention also provides a crystalline material composition, as-synthesized and in the anhydrous state, whose general formula, in terms of mole ratios, is (from about 1 to about 50)Q:(from about 0.5 to about 25) M2: (less than about 6.7)W203: 100 YOj wherein: Q is a 3,5-dimethylpiperidinium compound; M is alkali metal cations and/or alkaline earth metal cations; W is aluminum, boron, galliiim, indium, iron, titaniiim, or mixtures thereof; and Y is silicon, germanium, or mixtures thereof. In accordance with the present invention, there is also 02 provided the zeolite ZSM-11 having no intergrowth within its 03 crystalline structure of any other crystalline structure. 04 In particular, the zeolite ZSM-11 of this invention has no ne intergrowth of ZSM-5 crystalline structure. 06 07 The present invention further provides the zeolite ZSM-11 08 having no intergrowth with itscrystalline structure of 09 any other crystalline structure and having the X-ray diffraction pattern of Table I or Table II below. 11 12 The present invention also provides the zeolite ZSM-11 ^^ having a SiO2Al2O3mole ratio of less than 40. 14 Further provided in accordance with this invention is the zeolite ZSM-11 having a SiO2/Al203 mole ratio of less than 40 17 and having a cyclohexane micropore voliome of at least about ^^ 0.08 ml/g. 19 20 Among other factors, the present invention is based on the 21 discovery that the zeolite ZSM-11 can be made using 3,5-dimethylpiperidiniiim compounds as the organic templating ^^ agent. It is especially surprising that, by using these 3,5-dimethylpiperidinium compounds as the templating agent, ZSM-11 can be prepared in essentially pure phase form. ^^ Heretofore, it has been difficult to prepare ZSM-11 using 27 conventional templating agents without also crystallizing 28 the closely related zeolite ZSM-5. Also, the present 29 invention permits the synthesis of ZSM-11 with relatively 30 low SiOj/AljOj mole ratios, i.e., on the order of 25-40. In 31 addition, it has surprisingly been found that the ZSM-11 32 .... prepared in accordance with this invention having a SiO2/Al2O3 mole ratio of less than 40 has a high cyclohexane 02 micropore volume, ie., at least about 0.08 ml/g. 03 04 DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 05 In its process embodiment the present invention comprises: 07 08 (a) preparing an aqueous solution comprising sources 09 of oxides capable of forming ZSM-11 and at least one 3,5-dimethylpiperidinium compound; 11 12 (b) maintaining the aqueous solution under conditions 13 sufficient to form crystals of ZSM-11; and 14 (c) recovering the crystals of ZSM-11. 16 17 The Tempi at ing Aaent 18 19 The templating agents useful in the present process are 20water-soluble 3,5-dimethylpiperidinium compounds which are 21 capable of acting as a templating agent to form ZSM-11. They have a molecular structure of the general form: 23 24 25 26 27 28 29 ^° wherein R1and R2independently represent an alkyl group, 31 either branched or unbranched, substituted or unsubstituted, 32 containing from 1 to about 7 carbon atoms, with the proviso ^^ that R1and R2are not both methyl. In addition, R1and R234 together may comprise a cyclic alkyl ring system, which, 02 including the positively charged nitrogen atom, contains 03 from 4 to 7 atoms, said ring system being unsiabstituted or 04 substituted with branched or unbranched alkyl groups having, 05 e.g., one to three carbon atoms. X" is an anion which is not detrimental to the formation of the ZSM-ll, such as 07 those described below. Preferred 3,5-DMP conpounds are 08 3,5-dimethyl-N,N-diethylpiperidinium compounds; 3,5- 09 dimethyl-N-methyl-N-ethylpiperidinium compounds; spiro 3,5- dimethylpiperidinium compounds such as l-azonia-3,5,7- trimethyl-spiro[5.4] decane compounds. 12 13 The anion for the salt may be essentially any anion such as 14 halide or hydroxide which is not detrimental to the formation of the molecular sieve. As used herein, "halide" refers to the halogen anions, particularly fluorine, 17 chlorine, bromine, iodine, and combinations thereof. Thus, IB representative anions include hydroxide, acetate, sulfate, carboxylate, tetrafluoroborate, and halides such as 20 fluoride, chloride, bromide, and iodide. Hydroxide and 21 iodide are particularly preferred as anions. 22 ^^ The Preparation of ZSM-ll 24 25 • • The process of the present invention comprises forming a reaction mixture containing sources of alkali and/or 27 alkaline earth metal (M) cations; an oxide of aluminum, 28 boron, iron, gallium, indium, titanium, or mixtures thereof (W); an oxide of silicon, germanium or mixtures thereof (Y); 30 a 3,5-DMP templating agent (Q); and water, said reaction 31 • • mixture having a composition in terms of mole ratios within 32 the following ranges: 01 Reactants General Preferred 02 03 YO2/W2O3 15 and greater 25 and greater 04 OH-/YO2 0.1-0.6 0.15-0.40 05 Q/YO2 0.01-0.50 0.02-0.40 06 M+/YO2 0.01-0.50 0.03-0.40 07 H2O/YO2 15-100 20-50 08 09 In preparing the zeolite ZSM-11 according to the present invention, the reactants and the 3,5-DMP templating agent are dissolved in water and the resulting reaction mixture is 12 maxntained at an elevated temperature untxl crystals are 13 formed. The temperatures during the hydrothermal 14 crystallization step are typically maintained from about 15 100°C to about 250"C, preferably from about 140*'C to about 200*'C. The crystallization period is typically greater than 17 1 day and generally about 1 to about 40 days. Preferably 18 the crystallization period is from about 2 to about 20 days. 19 20 The hydrothermal crystallization is usually conducted under 21 pressure and usually in an autoclave so that the reaction 22 . . . mixture is subject to autogenous pressure. The reaction 23 mixture can be stirred during crystallization. 24 25 Once the crystals have formed, the solid product is 26 separated from the reaction mixture by standard mechanical 27 separation techniques, such as filtration. The crystals are 28 water-washed and then dried, e.g., at 90°C to 150°C for from 29 8 to 24 hours, to obtain the as-synthesized zeolite 30 crystals. The drying step can be performed at atmospheric or subatmospheric pressures. 01 During the hydrothermal crystallization step, the crystals 02 can be allowed to nucleate spontaneously from the reaction 03 mixture. The reaction mixture can also be seeded with 04 ZSM-11 crystals both to direct, and accelerate the 05 crystallization, as well as to minimize the formation of any 06 undesired crystalline phases. When seed crystals are used, 07" typically 0.1% to about 10% of the weight of silica used in 08 the reaction mixture are added. 09 10 Due to the unpredictability of the factors which control nucleation and crystallization in the art of crystalline oxide synthesis, not every combination of reagents, reactant 13 ratios, and reaction conditions will result in crystalline products. Selecting crystallization conditions which are effective for producing crystals may require routine 16 modifications to the reaction mixture or to the reaction conditions, such as temperature, and/or crystallization 18 time. Making these modifications are well within the 19 capabilities of one skilled in the art. 20 The ZSM-11 product made by the process of this invention has 22 • an as-synthesized composition comprising, in terms of mole 23 ratios in the anhydrous state, (from about 1 to about 24 50)Q: (from about 0.5 to about 25)M20: (less than about 25 6.7)W203: 100 YO2 where M, Q, W and Y are as defined above. 26 27 The ZSM-11 product was identified by its X-ray diffraction 28 (XRD) pattern. The X-ray powder diffraction patterns were 29 determined by standard techniques. The radiation was the 30 K-alpha/doublet of copper. A scintillation counter 31 spectrometer with a strip-chart pen recorder was used. The 32 peak heights I and the positions, as a function of 2d where 33 θ is the Bragg angle, were read from the relative 34 01 intensities, 100 x I/I0where I0 is the intensity of the 02 Strongest line or peak, and d, the interplanar spacing in 03 Angstroms corresponding to the recorded lines, can be 04 calculated. 05 The X-ray diffraction pattern of Table I is representative 07 of a calcined borosilxcate ZSM-11 made in accordance with 08 this invention. Minor variations in the diffraction pattern 09 can result from variations in the silica-to-alumina or silica-to-boron mole ratio of the particular sample due to changes in lattice constants. In addition, sufficiently 12 small crystals will affect the shape and intensity of peaks, 13 leading to significant peak broadening. 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 01 TABLE I 02 03 Calcined Borosilicate ZSM-ll 04 05 d (A) I/I,x 100 06 14.04 0.50 07 11.04 84.6 08 09 9.95 100.0 10 6.66 7.5 11 12 5.94 16.6 13 5.54 9.0 14 4.98 15.1 15 16 4.58 4.0 17 4.34 5.3 18 19 3.82 90.3 20 3.70 25.2 21 3.32 13.8 22 23 3.04 5.9 24 2.97 10.4 25 2g 2.00 20.4 27 28 The X-ray diffraction pattern of Table II is representative 29 of a calcined all-silicate ZSM-ll made in accordance with 30 this invention. 31 32 33 34 01 TABLE II 02 03 Calcined All-Silica ZSM-ll 04 05 06 d (A) I/I0x 100 07 14.18 1.8 08 11.13 100.00 09 10 10.02 53.7 11 6.69 9.1 12 13 5.98 14.3 14 5.56 9.1 15 5.01 5.6 16 17 4.60 3.6 18 4.35 3.9 19 20 3.84 53.1 21 3.71 24.1 22 3.48 2.7 23 24 3.06 7.9 25 2.98 10.9 26 27 2.00 10.5 28 29 Calcination can also result in changes in the intensities of 30 the peaks as well as minor shifts in the diffraction 31 pattern. The zeolite produced by exchanging the metal or 32 Other cations present in the zeolite with various other 33 cations (such as H+or NH4+) yields essentially the same 34 diffraction pattern, although again, there may be minor shifts in the interplanar spacing and variations in the 02 relative intensities of the peaks. Notwithstanding these 03 minor perturbations, the basic crystal lattice remains 04 unchanged by these treatments. 05 06 07 The ZSM-ll of this invention is in pure phase form. As used 08 herein, the phrase "pure phase form" refers to the fact that 09 the ZSM-ll of this invention is composed of crystals having only the structure of ZSM-ll, i.e., the crystals contain no other crystal structure as an intergrowth with the ZSM-ll 12 Structure. It is believed that, heretofore, although "pure" 13 ZSM-ll has been reported as having been prepared, these 14 materials have actually contained some amount of an 15 intergrowth of another crystal structure, typically ZSM-5. 14 One of the principal advantages of this invention is that it 17 provides ZSM-ll without these intergrowths of other crystal 18 structures. 19 20 It is believed that the peak in Tables I and II above found 21 at about d = 14A demonstrates that the ZSM-ll of this 22 invention is in pure phase form. This peak is not found in 23 X-ray diffraction patterns of ZSM-ll which contains ZSM-5 24 intergrowth, and does appear in Tables I and II where it 25 would be expected in a calculated X-ray diffraction pattern 26 for pure phase ZSM-ll. In addition, the intensities of the 27 peaks in Tables I and II above are consistent with the 28 intensities expected for a pure phase ZSM-ll. 29 30 31 The ZSM-ll of this invention can be prepared having a 32 SiO2/Al2O3 mole ratio lower than conventional ZSM-ll 32 materials. Thus, the ZSM-ll of this invention can be made 33 34 01 with a SiO/Al2O3 mole ratio less than 40, preferably 35 or 02 less, and more preferably about 30. 03 04 . . One surprising characteristic of the ZSM-11 of this 05 invention which has a SiO2/Al2O3 mole ratio below 40 is that it has a high cyclohexane micropore volume. Cyclohexane 07 micropore volume is measured by a method based on that 08 described by G. R. Landolt in Anal. Chem., Vol. 43, No.3, 09 613-615, 1971. The zeolite is dried by heating overnight at 650°F in air. It is then loaded into ampoules, placed in the adsorption chamber and evacuated to less than one 12 micron. Following this, the samples are connected to the 13 adsorbate, in this case cyclohexane. The vapor pressure of 14 the cyclohexane is measured with a pressure transducer. The 15 samples are at 22°C and measurements are usually made at relative partial pressure (P/PQ) of close to 0.15. The 17 equilibration process usually takes 3-6 hours. Once the 18 sample has equilibrated, it is removed from the chamber and 19 reweighed to determine the amount of cyclohexane adsorbed. 20 21 Using the method described above, the ZSM-11 of this 22 invention having a Si02/Al203 mole ratio below 40 has 23 micropore volumes of at least about 0.08 ml/g, preferably at 24 least about 0.09 ml/g, and more preferably at least about 25 0.10 ml/g. 26 27 Typically, the ZSM-11 crystalline material, is thermally 28 treated (calcined) prior to use as a catalyst. Usually, it 29 is desirable to remove the alkali metal cation by ion 30 exchange and replace it with hydrogen, ammonium, or any 31 desired metal ion. The zeolite can be leached with 32 chelating agents, e.g., EDTA or dilute acid solutions, to 33 increase the silica/aliimina mole ratio. The zeolite can 34 also be steamed; steaming helps stabilize the crystalline 02 lattice to attack from acids. The zeolite can be used in 03 intimate combination with hydrogenating components, such as 04 tungsten, vanadium molybdenium, rhenium, nickel cobalt, chromium, manganese, or a noble metal, such as palladium or platinum, for those applications in which a hydrogenation- 07 dehydrogenation function is desired. Typical replacing 08 cations can include hydrogen and hydrogen precursors, rare 09 earth metals, and metals from Groups IIA, IIIA, IVA, IB, 10 IIB, IIIB, IVB, VIB, and VIII of the Periodic Table of Elements. Of the replacing cations, hydrogen and cations of metals such as rare earth, Mn, Ca, Mg, Zn, Cd, Pt, Pd, 13 Ni, Co, Ti, Al, Sn, Ga, In and Fe are particularly preferred. 15 The ZSM-ll prepared by the present process is useful in 17 hydrocarbon conversion reactions. Hydrocarbon conversion 18 reactions are chemical and catalytic processes in which 19 carbon containing compounds are changed to different carbon 20 containing compounds. Examples of hydrocarbon conversion 21 reactions include catalytic cracking, hydrocracking, 22 dewaxing, alkylation, and olefin and aromatics formation 23 reactions. 24 25 The following examples demonstrate but do not limit the 26 present invention. 27 28 EXAMPLES 29 30 There are numerous variations on the embodiments of the 31 present invention illustrated in the Examples which are 32 possible in light of the teachings supporting the present 33 invention. It is therefore understood that within the scope 34 of the following claims, the invention may be practiced 02 Otherwise than as specifically described or exemplified. 03 04 Example 1 05 06 Preparation of 3.5-dimethyl-N.N-diethylpiperidinium 07 hydroxide templating agent (Template A) 08 09 200 Grams of 3,5-dimethylpiperidine, 255 grams of potassium bicarbonate and 1700 ml of methanol were added to a 3-liter 3-necked flask which was equipped with a mechanical stirrer, 12 addition funnel and reflux condenser. 794 Grams of ethyl 13 iodide was added to the resulting reaction mixture and, once 14 addition was complete, the mixture was heated for three days at reflux. After cooling, the reaction mixture was concentrated and the desired solids isolated. The product, 3,5-dimethyl-N,N-diethylpiperidinium iodide, was 18 recrystallized from hot acetone/methanol. 19 20 Ion exchange to the corresponding hydroxide was achieved 21 using Bio-Rad AG1-X8 anion exchange resin. The hydroxide ion concentration was determined by titration of the 23 resulting solution using phenolphthalein as the indicator. 24 25 Example 2 26 27 Synthesis of Aluminosilicate ZSM-11 28 29 3.66 Grams of a Template A solution (0.614 mmol OH"/g) was 30 mixed with 1.1 gram of 1.0 N KOH, 2.52 grams of water and 1.75 grams of Ludox AS-30 aqueous colloidal silica solution 32 (DuPont). Nalco 1SJ612 (alumina coated silica sol: 0.57 33 gram) was then added to the reaction mixture, which was 34 placed in a Teflon cup. The cup was sealed in a Parr 4745 02 02 reactor and heated at 170°C for 18 days. The settled 03 product of this reaction was filtered, washed with water and 04 determined by XRD to be ZSM-11. The product's SiO2/Al2O3 mole ratio was found to be 60. 06 07 Example 3 08 09 Synthesis of Borosilicate ZSM-11 10 3.66 Grams of a solution of Template A in its hydroxide form 12 (0.614 mmol OH/g) was mixed with 1.95 grams of 1.0 N NaOH 13 and 6.25 grams of water. Sodium borate (0.057 grams) was 14 . . . dissolved in this solution, and then 0.92 grams of Cabosil 15 M-5 filmed silica was added. This mixture was placed m a Teflon cup which was heated to 160°C in a Parr 4745 reactor 17 and rotated at 43 rpm. After 10 days, a settled product was 18 obtained which was filtered, washed with water and 19 determined by XRD to be ZSM-11. 20 21 Example 4 22 23 Synthesis of Borosilicate ZSM-11 24 25 3.66 Grams of a solution of Template A in its hydroxide form 26 (0.614 mmol OH-/g) was mixed with 1.36 grams of Ludox AS-30 27 aqueous colloidal silica solution (DuPont) . Sodiiam borate 28 (0.045 grams) was added to this solution and the resulting 29 mixture was stirred until all of the solid had dissolved. 30 This solution was heated to 150°C in a Blue M oven for 21 31 days. The product was isolated and determined by XRD to be 32 ZSM-11. Elemental analysis showed this material to have a 33 SiO2/BzO3 mole ratio of 116. 34 Example 5 02 03 Synthesis of Borosilicate ZSM-ll 04 05 4.40 Grams of a solution of Template A in its hydroxide form 06 (0.614 mmol Off/g) was mixed with 1.3 grams of 1.0 N NaOH 07 and 3.30 grams of water. Boric acid (0.124 gram) was 08 dissolved in this solution, followed by the addition of 0.75 09 gram of Cabosil M-5 fumed silica. This reaction mixture was placed in a Teflon cup which was heated to 160°C and rotated at 43 rpm. After 19 days, a settled product was obtained, 12 which was determined by XRD to be ZSM-ll. 13 14 Example 6 15 Synthesis of Aluminosilicate ZSM-ll 17 With SIOT/AL2O3 Mole Ratio Less Than 40 18 0.30 gram of Template A in its hydroxide form (0.614 mmol 19 OH/g) was mixed with 0.20 gram of solid KOH, 0.08 gram of 20 Reheis F2000 hydrated aluminum hydroxide and 11.4 grams of 21 water. To this solution was added 0.90 grams of Cabosil M-5 22 fumed silica (98% SiO2) . 0.18 Gram of isopropylamine was 23 next added dropwise and the resulting mixture was stirred in 24 a 23 ml Teflon cup for a Parr 4745 reactor. The reactor was 25 sealed and heated to 170°C on a rotating spit (43 rpm) of a Blue M oven. After 8 days, the reaction was complete and 27 the product was filtered, washed with water and air-dried. 28 The resulting product was determined by XRD to be ZSM-ll, 29 and had a SiO2/Al2O3 mole ratio of 31. 30 31 32 33 34 Example 7 02 03 Synthesis of Aluminoailicate ZSM-11 04 05 0.49 gram of Template A in its hydroxide form (0.614 mmol OH/g) was mixed with 0.20 grams of solid KOH, 0.08 gram of 07 Reheis F2000 hydrated alviminiim hydroxide and 11.4 grams of 08 water. To this solution was added 0.90 grams of Cabosil M-5 09 fumed silica (98% S1O2) and 0.005 gram of ZSM-11 crystals as seeds. The resulting mixture was stirred in a 23 ml Teflon cup for a Parr 4745 reactor which was then sealed and heated 12 to 170°C on a rotating spit (43 rpm) of a Blue M oven. 13 After 7 days, the reaction was complete and the product was 14 filtered, washed with water and air-dried. The resulting 15 product was determined by XRD to be ZSM-11. 16 17 Example 8 18 19 Calcination 20 21 The product from Example 6 was calcined in the following 22 manner. A thin bed of material was heated in a muffle furnace from room temperature to 120°C at a rate of 1°C per minute and held at 120°C for three hours. The temperature was then ramped up to 540°C at the same rate and held at 26 this temperature for five hours, after which it was 27 increased to 594°C and held there for another five hours. A 28 50/50 mixture of air and nitrogen was passed over the 29 zeolite at a rate of 20 standard cubic feet per minute 30 during heating. 31 32 33 34 Example 9 02 Micropore Volume of ZSM-ll 03 04 The nitrogen micropore volume of the calcined material from 05 Example 8 was found to be 0.15 cc/g, and the BET area was 382 M2/g. The cyclohexane micropore volume was determined to be 0.103 cc/g (8.0 wt%) at a P/P0 of 0.15 at temperature 08 220C. 09 The cyclohexane micropore volume was determined (temperature = 22°C; P/Po = 0.13) for those materials shown in the table 12 below. In some cases, the ZSM-ll was made using a mixture 13 of isobutylamine (IBA) and Template A(A) . 14 Sample SiO2/Al203 Cyclohexane (ml/g) IBA/Si* A/Si* 15 16 ZSM-ll" 33 0.0799 0.21 0.02 17 ZSM-ll" 33 0.095 - 0.02 18 ZSM-ll" 50 0.1057 - 0.15 e 19 20 ZSM-ll" 33 0.0913 0.21 0.02 ZSM-ll" 33 0.0875 0.15 0.02 ZSM-ll" 33 0.0897 0.10 0.02 22 ZSM-ll" 33 0.0877 0.05 0.02 23 24 ZSM-Sd - 0.0377 - 0.15f 25 ZSM-ll/ 50 0.0542 - 0.15e ZSM-5d 26 27 a Mole ratio in reaction mixture. Mole ratio in product is 28 expected to be slightly lower. b ZSM-ll in pure phase form made in accordance with this 29 invention 3Q c For comparative purposes d An intergrowth of ZSM-ll and ZSM-5 for comparative 31 purposes 32 e Template used was tetrabutylammonium cation f Template used was tetrapropylammonium cation. 33 34 01 Example 10 02 03 Ion Exchange 04 05 Ion-exchange of the calcined ZSM-11 material of Example 8 is executed using NH4NO3 to convert the zeolite from its Na+ to its corresponding NH4+ form, and ultimately, the Na+ form. 08 Typically, the same mass of NH4NO3 as zeolite is slurried in 09 water at a mass ratio of 25-50:1 water to zeolite. The exchange solution is heated at 95°C for 2 hours and then filtered or decanted. The process can be repeated up to 12 three times. Following the final exchange, the zeolite is 13 filtered, washed several times with water, and dried. This 14 NH4-11 form of ZSM-11 can then be converted to the H+ form by 15 calcination as described in Example 8 to 540°C. 16 Example 11 18 Synthesis of All-Silica ZSM-11 19 20 3.66 Grams of a solution of Template A in its hydroxide form 21 (0.614 mmol 0H7g) was mixed with 1.5 g of 1.0 N KOH and 22 6.71 g of water. 0.92 Gram of Cabosil M-5 filmed silica was 23 then added to the solution and the resulting mixture was 24 stirred until it was homogeneous. Seeds of ZSM-11 (0.006 g) 25 were added to the mixture and the resulting mixture was 26 heated to 160°C in a Parr 4745 reactor and rotated at 43 27 rpm. After three days, a settled product was obtained which 28 was filtered, washed with water and determined by X-ray 29 diffraction to be ZSM-11 in the pure phase form. 30 31 32 33 34 WE CLAIM: 1. A process for preparing the zeolite ZSM-11 which comprises: (a)preparing an aqueous solution comprising sources of (1) an alkali metal oxide, alkaline earth metal oxide or mixtures thereof; (2) an oxide selected from the oxides of aluminum, boron, iron, gallium, indium, titanium, or mixtures thereof; (3) an oxide selected from oxides of silicon, germanium or mixtures thereof; and (4) at least one 3,5-dimethylpiperidinium compound as a templating agent having the general formula wherein R1 and R2 independently represent an alkyl group, either branched orunbranched, substituted or unsubstituted, containing from 1 to 7 carbon atoms, with the proviso that R1 and R2 are not both methyl, or R1 and R2 together comprise a cyclic alkyl ring system, which, including the positively charged nitrogen atom, contains from 4 to 7 atoms, said ring system being unsubstituted or substituted with branched or unbranched alkyl groups, and X is an anion which is not detrimental to the formation of the ZSM-11; said aqueous solution comprises, in terms of mole ratios, the following: YO2/W2O3 15 and greater OH'/YO2 0.1-0.6 Q/YO2 0.01-0.50 M/YO2 0.01-0.50 H2O/O2 15-100 where Y is silicon, germanium or mixtures thereof; W is aluminum, boron, iron, gallium, indium, titanium or mixtures thereof; Q is a 3,5-dimethylpiperidinium compound; and M is an alkali metal, alkaline earth metal or mixtures thereof (b)maintaining the aqueous solution under conditions sufficient to form crystals of ZSM-U; and (c) recovering the crystals of ZSM-11, 2. The process according to claim 1 wherein X is hydroxide. 3. The process according to claim 1 wherein the 3,5-dimethylpiperidinium compound is a 3,5-dimethyl-N,N-diethylpiperidinium compound. 4. The process according to claim 1 wherem the 3,5-dimethylpiperidinium compound is a l-azonia-3, 5,7-trimethyl-spiro [5.4]decane compound. 5. The process according to claim 1 wherein the 3,5-dimethylpiperidinium compound is a 3,5-dimethyl-N-methyl-N-ethylpiperidinium compound. 6. The process according to claim 1 wherem the oxides are (1) sodium oxide (2) aluminum oxide and (3) silicon oxide. 7. The process according to claim 1 wherein the oxides are (1) potassium oxide (2) aluminum oxide and (3) silicon oxide. 8. The process according to claim 1 wherein the oxides are (1) sodium oxide (2) boron oxide and (3) silicon oxide. 9. The process according to claim 1 wherein said aqueous solution comprises, in terms of mole ratios, the following: YO2/W2O3 25 and greater OH7Y02 0.15-0.40 Q/YO2 0.02-0.40 M+/Y02 0.03-0.40 H2O/YO2 20-50 10. A process for preparing the zeolite ZSM-U substantially as herein described and exemplified.

Documents:

170-mas-95 claims.pdf

170-mas-95 correspondences-others.pdf

170-mas-95 correspondences-po.pdf

170-mas-95 description (complete).pdf

170-mas-95 form-1.pdf

170-mas-95 form-26.pdf

170-mas-95 form-4.pdf

170-mas-95 others document.pdf