HIGHLY EFFICIENT SOLIDOTHERMAL SYNTHESIS OF ZEOLITIC MATERIALS

Abstract

A process for preparing a zeolitic material having a zeolitic framework structure which exhibits a molar ratio (aAl.sub.2O.sub.3):SiO.sub.2 or a crystalline precursor thereof, comprising (i) preparing a mixture comprising H.sub.2O, one or more compounds comprising Si from which SiO.sub.2 in the zeolitic framework structure is formed, said one or more compounds comprising a silica gel exhibiting a molar ratio (c H.sub.2O):SiO.sub.2 and optionally one or more compounds comprising Al from which Al.sub.2O.sub.3 in the zeolitic framework structure is formed; (ii) subjecting the mixture obtained in (i) to crystallization at a crystallization temperature in the range of from 110 to 350 C., preferably in the range of from 190 to 350 C., and for a crystallization time in the range of from 0.1 to 48 h.

Claims

1: A process for preparing a zeolitic material having a zeolitic framework structure which exhibits a molar ratio (a Al.sub.2O.sub.3):SiO.sub.2 or a crystalline precursor thereof, wherein a is a number in the range of from 0 to 0.5, said process comprising: (i) preparing a mixture comprising H.sub.2O, one or more compounds comprising Si from which SiO.sub.2 in the zeolitic framework structure is formed, said one or more compounds comprising a silica gel exhibiting a molar ratio (c H.sub.2O):SiO.sub.2 wherein c is a number in the range of from 0 to 2.5, and optionally one or more compounds comprising Al from which Al.sub.2O.sub.3 in the zeolitic framework structure is formed, wherein said mixture comprises the one or more compounds comprising Si and optionally the one or more compounds comprising Al in amounts so that for Si expressed as SiO.sub.2 and for Al expressed as Al.sub.2O.sub.3, the mixture exhibits a molar ratio (b H.sub.2O):(a Al.sub.2O.sub.3+SiO.sub.2) wherein b is a number in the range of from 0 to 2.0; and (ii) subjecting the mixture obtained in (i) to crystallization at a crystallization temperature in the range of from 110 to 350 C., and for a crystallization time in the range of from 0.1 to 48 h, obtaining the zeolitic material having a zeolitic framework structure which exhibits a molar ratio (a Al.sub.2O.sub.3):SiO.sub.2 or the crystalline precursor thereof.

2: The process of claim 1, wherein the zeolitic framework structure of the zeolitic material exhibits framework type BEA, CHA, MFI, MEL, MOR, CDO, AEI, FER, SAV, or a mixed type of two or more thereof.

3: The process of claim 1, wherein c is in the range of from 0.01 to 2.4.

4: The process of claim 1, wherein b is in the range of from 0.01 to 2.

5: The process of claim 1, wherein the mixture prepared in (i) comprises two or more compounds comprising Si from which SiO.sub.2 in the zeolitic framework structure is formed, wherein the two or more compounds comprising Si from which SiO.sub.2 in the zeolitic framework structure is formed comprise at least one selected from the group consisting of a sodium silicate, a white carbon black, an amorphous silica powder, and a fumed silica.

6: The process of claim 1, wherein the one or more compounds comprising Al from which Al.sub.2O.sub.3 in the zeolitic framework structure is formed comprise one or more of an aluminum sulfate, a sodium aluminate, and a boehmite.

7: The process of claim 1, wherein the mixture prepared in (i) further comprises a compound comprising an alkali metal M in an amount so that for M expressed as M.sub.2O, the mixture exhibits a molar ratio (d M.sub.2O):(a Al.sub.2O.sub.3+SiO.sub.2) wherein d is a number in the range of from 0 to 0.6.

8: The process of claim 1, wherein the mixture prepared in (i) further comprises seed crystals SC comprising zeolitic material having a zeolitic framework structure exhibiting the framework type of the zeolitic material to be prepared, wherein the mixture prepared in (i) comprises the seed crystals SC in an amount so that mixture exhibits a weight ratio of the seed crystals SC relative to the mixture prepared in (i) in the range of from 0 to 5%.

9: The process of claim 1, wherein the mixture prepared in (i) further comprises an organotemplate compound OC for the zeolitic material to be prepared, wherein the mixture prepared in (i) comprises the organotemplate compound OC in an amount so that mixture exhibits a molar ratio (f OC):(a Al.sub.2O.sub.3+SiO.sub.2) wherein f is a number in the range of from 0 to 1.5.

10: The process of claim 1, wherein the mixture prepared in (i) optionally further comprises a compound comprising an alkali metal M in an amount so that for M expressed as M.sub.2O, the mixture exhibits a molar ratio (d M.sub.2O):(a Al.sub.2O.sub.3+SiO.sub.2) wherein d is a number in the range of from 0 to 0.6, wherein the mixture prepared in (i) optionally further comprises seed crystals SC comprising a zeolitic material having a zeolitic framework structure exhibiting the framework type of the zeolitic material to be prepared, wherein the mixture prepared in (i) comprises the seed crystals SC in an amount so that mixture exhibits a weight ratio of the seed crystals SC relative to the mixture prepared in (i) in the range of from 0 to 5%, wherein the mixture prepared in (i) optionally further comprises an organotemplate compound OC for the zeolitic material to be prepared, wherein the mixture prepared in (i) comprises the organotemplate compound OC in an amount so that mixture exhibits a molar ratio (f OC):(a Al.sub.2O.sub.3+SiO.sub.9) wherein f is a number in the range of from 0 to 1.5, wherein at least 99 weight-% of the mixture prepared in (i) consist of H.sub.2O, the one or more compounds comprising Si from which SiO.sub.2 in the zeolitic framework structure is formed, optionally the one or more compounds comprising Al from which Al.sub.2O.sub.3 in the zeolitic framework structure is formed, optionally the compound comprising an alkali metal M, optionally the seed crystals SC and optionally the organotemplate compound OC.

11: The process of claim 1, wherein preparing the mixture in (i) comprises grinding, wherein the grinding is carried out at a temperature of the mixture in the range of from 10 to 50 C.

12: The process of claim 1, wherein subjecting the mixture obtained in (i) to crystallization according to (ii) is carried out in a pressure-tight vessel.

13: The process of claim 1, wherein the crystallization temperature according to (ii) is in the range of from 200 to 350 C., and wherein the crystallization time according to (ii) is in the range of from 0.2 to 36 h.

14: The process of claim 1, wherein the zeolitic material obtained in (ii) or the crystalline precursor obtained in (ii) is calcined.

15: A zeolitic material having a zeolitic framework structure which exhibits a molar ratio (a Al.sub.2O.sub.3):SiO.sub.2 or a crystalline precursor thereof, obtained by a process according to claim 1, wherein a is a number in the range of from 0 to 0.5.

Description

EXAMPLES

Reference Example 1: .SUP.29.Si NMR Spectra

[0187] For the determination of the silanol concentration, the .sup.29Si MAS NMR experiments were carried out at room temperature on a VARIAN Infinity Plus-400 spectrometer using 7.0 mm ZrO.sub.2 rotors. The .sup.29Si MAS NMR spectra were collected at 79.5 MHz using a 4.0 s /4 (microsecond pi/4) pulse with 60 s recycle delay and 4000 scans. All .sup.29Si spectra were recorded on samples spun at 4 kHz, and chemical shifts were referenced to 4,4-dimethyl-4-silapentane sulfonate sodium (DSS). For the determination of the silanol group concentration, a given .sup.29Si MAS NMR spectrum is deconvolved by the proper Gaussian-Lorentzian line shapes. The concentration of the silanol groups with respect to the total number of Si atoms is obtained by integrating the deconvolved .sup.29Si MAS NMR spectra.

[0188] All .sup.29Si solid-state NMR experiments were performed using a VARIAN Infinity Plus-400 spectrometer with 300 MHz .sup.1H Larmor frequency (Varian, America). Samples were packed in 7 mm ZrO.sub.2 rotors, and measured under 5 kHz Magic Angle Spinning at room temperature. .sup.29Si direct polarization spectra were obtained using (pi/2)-pulse excitation with 5 microsecond pulse width, a .sup.29Si carrier frequency corresponding to 65 ppm in the spectrum, and a scan recycle delay of 120 s. Signal was acquired for 25 ms under 45 kHz high-power proton decoupling, and accumulated over 10 to 17 hours. Spectra were processed using Bruker Topspin with 30 Hz exponential line broadening, manual phasing, and manual baseline correction over the full spectrum width. Spectra were referenced with the polymer Q8M8 as an external secondary standard, setting the resonance of the trimethylsilyl M group to 12.5 ppm. The spectra were then fitted with a set of Gaussian line shapes, according to the number of discernable resonances. Fitting was performed using DMFit (Massiot et al., Magnetic Resonance in Chemistry, 40 (2002) pp 70-76). Peaks were manually set at the visible peak maxima or shoulder. Both peak position and line width were then left unrestrained, i.e., fit peaks were not fixed at a certain position. The fitting outcome was numerically stable, i.e., distortions in the initial fit setup as described above did lead to similar results. The fitted peak areas were further used normalized as done by DM Fit. For the quantification of spectrum changes, a ratio was calculated that reflects changes in the peak areas left hand and right hand.

Reference Example 2: XRD Spectra

[0189] X-ray powder diffraction (XRD) patterns were measured with a Rigaku Ultimate VI X-ray diffractometer (40 kV, 40 mA) using Cu(K alpha) (lambda=1.5406 Angstrom) radiation.

Reference Example 3: .SUP.13.C NMR Spectra

[0190] .sup.13C solid MAS NMR spectra were recorded on a Varian Infinity Plus 400 spectrometer. .sup.13C liquid NMR spectra were recorded on a Bruker Avance 500 spectrometer using a 5 mm QNP probe equipped with z-gradient coil.

Reference Example 4: SEM

[0191] Scanning electron microscopy (SEM) experiments were performed on Hitachi SU-1510 electron microscopes.

Reference Example 5: Nitrogen Sorption

[0192] The nitrogen sorption isotherms at the temperature of nitrogen liquid were measured using Micromeritics ASAP 2020M and Tristar system.

Reference Example 6: Sample Composition

[0193] The sample composition was determined by inductively coupled plasma (ICP) with a Perkin-Elmer 8000 emission spectrometer.

Reference Example 7: Thermogravimetry

[0194] The thermogravimetry-differential thermal analysis (TG-DTA) experiments were carried out on a Perkin-Elmer TGA 7 unit in air at heating rate of 10 C./min in the temperature range from room temperature to 1000 C.

Reference Example 8: Solid Silica Gel

[0195] The solid silica gel from Qingdao Haiyang Chemical Reagent Co, Ltd., had a pore volume of 0.9-1.0 cm.sup.3/g (BET (3H-2000PS2) made by Beishide Instrument Technology (Beijing) Co., Ltd), a pore size of 10 nm (BET), a particle size (percentage of particles for passing the sieve with 200 mesh) of >90%, a silica content of >98% (dissolved by HF, and chemical analysis), and a bulk density of 380-480 g/L (tapped and full filling 100 mL measuring cylinder).

Comparative Example 1: Hydrothermal Synthesis of RUB-36

[0196] 1.2 g of SiO.sub.2 (fumed silica; essentially no water contained) and 5.174 g of dimethyldiethylammonium hydroxide (DMDEAOH, 20 weight-% in water) were added together (1.00 SiO.sub.2:0.43 DMDEAOH:11.50 H.sub.2O) and stirred for 4 h, then transferred into an autoclave and crystallized at 140 C. for 14 d (oven: DGG-9070GD from ENXIN; the crystallization temperature referred to above is the oven temperature). The isolated yield of crystalline material of structure RUB-36 was 67.8%.

[0197] The BET specific surface area of the calcined product according to DIN 66131 (nitrogen absorption) was 288 m.sup.2/g. Furthermore, the calcined product had a micropore volume of 0.13 m.sup.3/g, determined according to DIN 66135.

[0198] FIG. 1 shows the XRD pattern of the non-calcined product, from which it is apparent that said product has a RUB-36 framework structure.

[0199] Comparative Example 1 was repeated but at different crystallization temperatures and crystallization times. Only amorphous material could be isolated after (a) 9 d at 160 C. (b) 3 d at 180 C. and (c) 12 d at 200 C. which shows that at higher temperatures and shorter times, the hydrothermal synthesis route is not possible.

Comparative Example 2: Hydrothermal Synthesis of a Zeolitic Material Having Framework Type MFI

[0200] Zeolite having a framework type MFI was synthesized under hydrothermal conditions according to Wang et al. in Chem. Commun., 2010, 46, 7418. As a typical run, 14 g of TEOS and 22 g of TPAOH (20 wt. %, diluted from TPAOH of 40 wt. %) were added into 22 g of distilled water, after fully dissolved, 0.093 g of aluminium isopropoxide was added. After stirring for 24-48 h, the gel was transferred into an autoclave and heated at 180 C. for 48 h. The organic templates were removed after calcination at 550 C. for 5 h.

Example 1: Solidothermal Synthesis of RUB-36

[0201] a) 1.2 g SiO.sub.2 solid silica gel according to Reference Example 8 (Qingdao Haiyang Chemical Reagent Co, Ltd.), 0.75 g dimethyldiethylammonium hydroxide (DMDEAOH, 50 weight-% in water) and 0.0254 g RUB-36 seed crystals (synthesized as described in Comparative Example 1 above;) were added into a mortar one by one and mixed together. After grinding for 5 minutes, the powder with molar composition of 1 SiO.sub.2:0.15 DMDEAOH:1.02 H.sub.2O was transferred to an autoclave and sealed. The solid mixture was crystallized at 200 C. for 1.5 days. [0202] The total yield was 82% based on the total raw materials (water excluded), and the yield with respect to SiO.sub.2 was 99.9%. The space-time-yield was 178 kg/m.sup.3/day. The space-time-yield reported in the literature (Gies et al.) was 5 kg/m.sup.3/day. [0203] The crystallized product RUB-36 was converted into H-form by calcination at 500 C. for 5 h. The BET specific surface area of the calcined product according to DIN 66131 is 281 m.sup.2/g. The material obtained had a micropore volume, determined according to DIN 66135, of 0.12 m.sup.3/g. FIG. 2 shows the SEM image of the non-calcined material obtained in Example 1 exhibiting the platelet morphology typical for layered zeolites. The XRD pattern is displayed in FIG. 4, pattern (d). [0204] b) The experiment was repeated, but at different crystallization temperatures. [0205] FIG. 3 shows the .sup.29Si NMR spectra of (a) RUB-36 prepared as described in Comparative Example 1 (Q3:Q4=28.3:71.7), (b) RUB-36 prepared as described in Example 1 a) at 140 C. for 20 d (Q3:Q4=26.0:74.0), (c) RUB-36 prepared as described in Example 1 a) at 180 C. for 3 d (Q3:Q4=25.4:74.6). These materials exhibit peaks at 106, 112, and 115 ppm, which are reasonably assigned to Q.sup.3 [Si(SiO).sub.3OH, 106 ppm] and Q.sup.4 [Si(SiO).sub.4, 112, and 115 ppm] silica species, respectively (see Fyfe et al.). It is noted that the Q.sup.4/Q.sup.3 ratio (74.6/25.4) of the inventive RUB-36 material according to (c) is higher than that (71.7/28.3) of the comparative material according to (a), indicating that the inventive RUB-36 materials a have higher silica condensation degree, which is very favorable for enhancement of thermal and hydrothermal stabilities of porous materials (Jomekian et al.). [0206] FIG. 4 shows XRD patterns of RUB-36 synthesized for (a) 20 d at 140 C., (b) 9 d at 160 C., (c) 3 d at 180 C., and (d) 1.5 d at 200 C. It can be seen from the XRD patterns that the crystallinity is apparently unaffected by applying higher crystallization temperatures. [0207] c) Example 1 a) was repeated at 180 C., 3 d but with different H.sub.2O/SiO.sub.2 molar ratios (a) 1.02 (b) 1.97 (c) 2.78 (c) 3.89 while keeping the DMDEA/SiO.sub.2 ratio at 0.15. Condition (a) resulted in phase pure RUB-36, (b) resulted in RUB-36 together with amorphous material, (c) resulted in amorphous material together with RUB-36 and (d) resulted solely amorphous material. [0208] Repeating Example 1 a) while further increasing the H.sub.2O/SiO.sub.2 molar ratio to 11.4 together with raising the DMDEA/SiO.sub.2 ratio to 0.43 (e), as well as a adjusting H.sub.2O:SiO.sub.2 molar ratio to 7.86 together with a DMDEA/SiO.sub.2 ratio of 0.97 (f), resulted in only amorphous materials for both conditions (e) and (f). [0209] FIG. 5 shows the .sup.13C NMR of (a) organic template as is, (b) template after 3 days at 180 C. for RUB-36 prepared according to Example 1, and (c) template after 3 days at 180 C. for RUB-36 prepared according to Comparative Example 1. [0210] It is shown that higher amounts of water present in the synthesis mixture typically for hydrothermal crystallization conditions led to decomposition of the organic template at elevated temperatures

Example 2: Solidothermal Synthesis of a Zeolitic Material Having Framework Type BEA

[0211] 1.29 g SiO.sub.2 solid silica gel according to Reference Example 8 (Qingdao Haiyang Chemical Reagent Co, Ltd.), 1.38 g of Na.sub.2SiO.sub.39H.sub.2O (analytical grade, SiO.sub.2 of 20 weight-%, Aladdin Chemistry Co., Ltd.), 0.108 g Boehmite (70 weight-% Al.sub.2O.sub.3, Liaoning Hydratight Science and Technology Development Co., LTD) and 0.06 g Beta seeds (Si/Al=12.5; XRD pattern shown in FIG. 11) were added into a mortar one by one and mixed together. After grinding for 5 minutes, the powder with molar composition of 0.18 Na.sub.2O:1 SiO.sub.2:0.03 Al.sub.2O.sub.3:1.73 H.sub.2O was transferred to an autoclave and sealed. The solid mixture was crystallized at (a) 6 d at 120 C., (b) 3 d at 140 C., (c) 1 d at 160 C., (d) 6 h at 180 C., and (e) 2 h at 200 C.

[0212] The yield for the inventive experiment (e) with respect to SiO.sub.2 was 95%. The space-time-yield was 2,523 kg/m.sup.3/day. The space-time yield reported in literature (Fan et al.) was 160 kg/m.sup.3/day.

[0213] The BET specific surface area of the ion exchanged and calcined product (e) according to DIN 66131 was 436 m.sup.2/g. Furthermore, the product had a micropore volume of 0.20 m.sup.3/g determined according to DIN 66135.

[0214] FIG. 6 shows the XRD pattern of the zeolitic product, crystallized (a) 6 d at 120 C., (b) 3 d at 140 C., (c) 1 d at 160 C., (d) 6 h at 180 C., and (e) 2 h at 200 C. from which it is apparent that the product has a BEA framework structure.

Example 3: Solidothermal Synthesis of a Zeolitic Material Having Framework Type MOR

[0215] SiO.sub.22 H.sub.2O was prepared by impregnating (water was added into the silica gel drop by drop, and the impregnated material was used directly) solid silica gel according to Reference Example 8 (Qingdao Haiyang Chemical Reagent Co, Ltd.) with demineralized water. 1.332 g of this SiO.sub.22H.sub.2O, 0.181 g of NaAlO.sub.2 (Sinopharm Chemical Reagent Co., Ltd.), 0.068 g NaOH (analytical grade, 96%, Sinopharm Chemical Reagent Co., Ltd.) and 0.03 g MOR seeds (prepared by crystallizing a synthesis gel with the composition of 0.16 Na.sub.2O:1 SiO.sub.2:0.07 Al.sub.2O.sub.3:2.14 H.sub.2O at 180 C. for 48 h; the XRD pattern so shown in FIG. 12) were added into a mortar one by one and mixed together. After grinding for 5 minutes, the powder with molar composition of 0.22 Na.sub.2O:1 SiO.sub.2:0.07 Al.sub.2O.sub.3:2.09 H.sub.2O was transferred to an autoclave and sealed. The solid mixture was crystallized at 240 C. for 1.5 h.

[0216] The yield with respect to SiO.sub.2 was 99.9%. The space-time-yield was 4,609 kg/m.sup.3/day. The space-time yield reported in literature (Ren et al.) was 67 kg/m.sup.3/day.

[0217] The obtained powder was subdued to triple ion-exchange with 1 M NH.sub.4NO.sub.3 solution at 80 C. for 2 h, followed by calcination at 550 C. for 4 h.

[0218] The BET specific surface area of the product in its H-form according to DIN 66131 was 383 m.sup.2/g. The Langmuir Surface Area according to DIN 66131 was 502 m.sup.2/g. Furthermore, the product had a micropore volume of 0.18 m.sup.3/g, determined according to DIN 66135.

[0219] FIG. 7 shows the XRD pattern of the zeolitic product from which it is apparent that the product has a MOR framework structure.

Example 4: Solidothermal Synthesis of a Zeolitic Material Having Framework Type MFI

Example 4a

[0220] 0.262 g of solid silica gel according to Reference Example 8 (Qingdao Haiyang Chemical Reagent Co, Ltd.), 1.422 g of Na.sub.2SiO.sub.39H.sub.2O (analytical grade, SiO.sub.2 of 20 weight-%, Aladdin Chemistry Co., Ltd.), 0.24 g TPABr (tetrapropylammonium bromide, analytical grade, 98%, Aladdin Chemistry Co., Ltd.) 0.46 g NH.sub.4Cl and 0.03 g MFI seeds (pure silica; the XRD pattern is shown in FIG. 13) were added into a mortar one by one and mixed together. After grinding for 5 minutes, the powder with molar composition of 0.53 Na.sub.2O:1 SiO.sub.2:0.1 TPABr:4.81 H.sub.2O was transferred to an autoclave and sealed. The solid mixture was crystallized at 240 C. for 0.5 h.

[0221] The total yield was 96.7% based on the total raw materials (water excluded), and the yield with respect to SiO.sub.2 was 99.9%. The space-time yield was 12,800 kg/m.sup.3/day. The space-time yield reported in literature (Hsu et al.) was 530 kg/m.sup.3/day.

[0222] The obtained powder was subjected to calcination at 550 C. for 5 h in order to remove the template followed by triple ion-exchange with 1 M NH.sub.4NO.sub.3 solution at 80 C. for 2 h, followed by calcination at 500 C. for 5 h. The yield based on SiO.sub.2 was 94.9% and the space-time yield was 11,028 kg/m.sup.3/day.

[0223] The BET specific surface area of the product in its H-form according to DIN 66131 was 408 m.sup.2/g. The Langmuir surface area according to DIN 66131 was 562 m.sup.2/g. Furthermore, the product had a micropore volume of 0.18 cm.sup.3/g, determined according to DIN 66135.

[0224] FIG. 8a shows the XRD pattern of the zeolitic product from which it is apparent that the product has a MFI framework structure.

Example 4b

[0225] 1.2 g of solid silica gel (Qingdao Haiyang Chemical Reagent Co, Ltd.), 0.293 g of NaOH (analytical grade, 96%, Sinopharm Chemical Reagent Co., Ltd.) and 0.625 g tetraethylammonium hydroxide (TEAOH; 35% in water, TCl) were added into a mortar one by one and mixed together. After grinding for 5 min, the powder with molar composition of 0.183 Na.sub.2O:1 SiO.sub.2:0.074 TEAOH:1.13 H.sub.2O was transferred to an autoclave and sealed. The solid mixture was crystallized at 200 C. for 3 h.

[0226] The yield with respect to SiO.sub.2 was 96.7%. The space-time yield was 2,792 kg/m.sup.3/day. The template was removed via calcination.

[0227] FIG. 8b shows the XRD pattern of the zeolitic product from which it is apparent that the product has a MFI framework structure.

Example 4c

[0228] 0.008 g of boehmite (Al.sub.2O.sub.3 of 70 wt. %, Liaoning Hydratight Co) was added into 1.0 g of Tetrapropylammonium hydroxide (TPAOH, 40 wt. %, Shanghai Aladdin Bio-Chem Technology Co., LTD), after fully dissolved, the mixture was fully grinded with 1.0 g of fumed silica (Shanghai Tengmin Industrial Co). Then, the powder mixture was transferred into an autoclave and sealed. After heating at 140 C. for 300 min (or alternatively at 180 C. for 180 min, or at 200 C. for 72 min), the sample was fully crystallized.

[0229] The H-form was then obtained by calcination at 550 C. for 5 h.

[0230] The yield with respect to SiO.sub.2 was more than 97%.

[0231] The BET specific surface area of the product in its H-form according to DIN 66131 was 434 m.sup.2/g. Furthermore, the product had a micropore volume of 0.182 cm.sup.3/g, determined according to DIN 66135.

[0232] FIG. 8c shows the XRD pattern of the zeolitic product obtained from which it is apparent that the product has a MFI framework structure.

Example 5: Solidothermal Synthesis of a Zeolitic Material Having Framework Type CHA

[0233] 1.026 g of solid silica gel according to Reference Example 8 (Qingdao Haiyang Chemical Reagent Co, Ltd.), 1.059 g of Na.sub.2SiO.sub.39H.sub.2O (analytical grade, SiO.sub.2 of 20 weight-%, Aladdin Chemistry Co., Ltd.), 0.456 g of Al.sub.2(SO.sub.4).sub.318 H.sub.2O (analytical grade, 99%, Sinopharm Chemical Reagent Co., Ltd.), 0.6 g N,N,N-trimethyladamantylammonium hydroxide (65% in H.sub.2O, BASF) and 0.025 g CHA seeds (seed crystals were synthesized by conventional hydrothermal crystallization for 7 days at 160 C. employing a synthesis gel of the following composition: 0.12 Na.sub.2O:1 SiO.sub.2:0.03 Al.sub.2O.sub.3:20.0 H.sub.2O; the XRD pattern is shown in FIG. 14) were added into a mortar one by one and mixed together. After grinding for 5 minutes, the powder with molar composition of 0.18 Na.sub.2O:1 SiO.sub.2:0.03 Al.sub.2O.sub.3:0.09 N,N,N-trimethyladamantylammonium hydroxide:2.76 H.sub.2O was transferred to an autoclave and sealed. The solid mixture was crystallized at 240 C. for 1.5 h.

[0234] The yield with respect to SiO.sub.2 was 99.2%. The space-time-yield was 4,738 kg/m.sup.3/day.

[0235] The crystallized product Na-CHA was converted into H-form by triple ion-exchange with 1 M NH.sub.4NO.sub.3 solution at 80 C. for 2 h, followed by calcination at 500 C. for 5 h.

[0236] FIG. 9 shows the XRD pattern of the zeolitic product obtained from which it is apparent that the product in its Na-form as well after ion exchange as H-form has a CHA framework structure/

[0237] The experiment was repeated but at different crystallization temperatures. FIG. 10 shows the XRD pattern of the zeolitic product obtained from (a) 5 d at 160 C., (b) 2 d at 180 C., (c) 12 h at 200 C., (d) 5 h at 220 C. and (e) 1.5 h at 240 C. from which it is apparent that the product has a CHA framework structure.

Example 6: Investigating the Effect of H.SUB.2.O/Si Ratio

[0238] The effect of varying the H.sub.2O/Si ratio in the overall raw mixture employed based on the protocol of Example 4c was investigated, wherein the heating step in the sealed autoclave was carried out at 180 C. for 24 h.

[0239] FIG. 16 shows the SEM images of zeolites having framework type MFI synthesized with different ratios of H.sub.2O/Si of the raw mixtures. Clearly, with increase of water amount, the sizes of crystals are increasing. For instance, a sample based on example 4c wherein the overall H.sub.2O/Si ratio in the raw materials used was 1:1 gave a crystal size at about 100-200 nm. However, when the H.sub.2O/Si ratios are increased to 3:1, 5:1, and 9:1, the sizes of obtained samples are increased to 500 nm, 3 m, and 5 m respectively. Accordingly, our results show that employing less water is helpful to decrease the zeolite crystal size within a certain scale of H.sub.2O/Si ratio. Apparently, the increase of water amount leads to the decrease of nucleation concentration, which is of great significance for the formation of smaller zeolite crystal size, as the lower nucleus concentration means the relatively lower speed of nucleation and higher speed of nucleus growth.

Example 7: Methanol-to-Olefins (MTO) Reaction with Zeolitic Material Having Framework Type MFI

[0240] The MTO reaction was carried out with a fixed-bed tubular steel reactor with an inner diameter of 8 mm and a length of 30 cm at atmospheric pressure. After 0.50 g of catalyst (20-40 mesh) from example 4c (according to the invention) or from comparative example 2, was loaded in the middle of tubular steel between two layers of quartz wool, it was pretreated in flowing nitrogen at 500 C. for 2 h and cooled down to the reaction temperature of 480 C. The methanol was injected into the catalyst bed by a pump with weight hourly space velocity (WHSV) of 1.0 h.sup.1. The products from the reactor were analyzed on-line by an Agilent 6890N gas chromatograph equipped with an FID detector and a PLOT-Al.sub.2O.sub.3 capillary column (50 m0.53 mm25 m). Selectivity to the products of interest was expressed as mass percentage of each product among all the detectable products except dimethyl ether.

[0241] FIG. 15 shows dependences of catalytic conversion of methanol and product selectivities on the reaction time with the Example 4c zeolite and Comparative Example 2 zeolite. Clearly, at early stage of catalytic reaction, the two catalysts are both very active, giving full conversion of methanol. For example, at reaction time of 1.0 h, the major products include alkanes (C.sub.1-C.sub.5), light olefins (ethylene, propylene, and butane), and aromatics. Notably, both of the two catalysts give very high propylene selectivity, while Example 4c gives 54.0%, which is even higher than the Comparative Example 2 at 52.9%. The total olefin (ethylene, propylene and butylene) selectivity of Example 4c and Comparative Example 2 are 81.9% and 82.1%, respectively, which are comparable. However, Example 4c gives lower ethylene selectivity at 9.6% and higher butylene selectivity at 18.3% respectively, whereas Comparative Example 2 catalyst gives 12.7% and 16.7% respectively. This phenomenon means Example 4c possesses higher selectivity for larger-sized olefins, ie, propylene and butylene, than the Comparative Example 2 catalyst, which may indicate the advantage of Example 4c at mass transfer during the catalytic reaction. Regarding the low value-added methane, Example 4c gives selectivity at 1.95% and Comparative Example 2 gives selectivity at 3.28%. Furthermore, compared to the Comparative Example 2 catalyst, the Example 4c catalyst exhibits remarkably prolonged catalyst lifetime. Notably, the lifetime of Example 4c was nearly three times longer than Comparative Example 2. The TG-DTA curves of the two deactivated catalysts show that Example 4c has the slower rate of coke deposition.

[0242] These results show that Example 4c which was synthesized in 3 h under solvent-free conditions has improved catalytic properties in the methanol-to-olefins reaction than the conventional hydrothermal synthesized ones.

SHORT DESCRIPTION OF THE FIGURES

[0243] FIG. 1 shows the XRD pattern of the un-calcined zeolitic product obtained in Reference Example 1. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0244] FIG. 2 shows the SEM image of the un-calcined zeolitic product obtained in Example 1 exhibiting the platelet morphology typical for layered zeolites

[0245] FIG. 3 shows the .sup.29Si NMR spectra offrom top to bottom(a) RUB-36 prepared according to Comparative Example 1 at 140 C. (Q3:Q4=28.3:71.7), (b) RUB-36 prepared according to Example 1 at 140 C. (Q3:Q4=26.0:74.0), (c) RUB-36 prepared according to Example 1 at 180 C. (Q3:Q4=25.4:74.6).

[0246] FIG. 4 shows XRD patterns of RUB-36 prepared according to Example 1from bottom to topsynthesized for (a) 20 d at 140 C., (b) 9 d at 160 C., (c) 3 d at 180 C., and (d) 1.5 d at 200 C. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0247] FIG. 5 shows the .sup.13C NMR of (a) organic template as is, (b) template after 3 days at 180 C. for RUB-36 prepared according to Example 1, and (c) template after 3 days at 180 C. for RUB-36 prepared according to Comparative Example 1.

[0248] FIG. 6 shows the XRD pattern of the zeolitic products (BEA) from Example 2from bottom to top , crystallized (a) 6 d at 120 C., (b) 3 d at 140 C., (c) 1 d at 160 C., (d) 6 h at 180 C., and (e) 2 h at 200 C. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0249] FIG. 7 shows the XRD pattern of the zeolitic product obtained in Example 3 from which it is apparent that the product has a MOR framework structure. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0250] FIG. 8a shows the XRD pattern of the zeolitic product obtained in Example 4a from which it is apparent that the product has a MFI framework structure. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0251] FIG. 8b shows the XRD pattern of the zeolitic product obtained in Example 4b from which it is apparent that the product has a MFI framework structure. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0252] FIG. 8c: shows the XRD pattern of the zeolitic product obtained in Example 4c from which it is apparent that the product has a MFI framework structure. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0253] FIG. 9 shows the XRD pattern of the zeolitic product obtained from Example 5 from which it is apparent that the product in its Na-form as well after ion exchange as H-form has a CHA framework structure. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0254] FIG. 10 shows the XRD pattern of the zeolitic products obtained from Example 5 prepared using different crystallization conditions. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0255] FIG. 11 shows the XRD pattern of the seed crystal material (BEA) used in Example 2. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0256] FIG. 12 shows the XRD pattern of the seed crystal material (MOR) used in Example 3. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0257] FIG. 13 shows the XRD pattern of the seed crystal material (MFI) used in Example 4. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0258] FIG. 14 shows the XRD pattern of the seed crystal material (CHA) used in Example 5. In the figure, the diffraction angle 2 theta in is shown along the abscissa and the intensities are plotted along the ordinate.

[0259] FIG. 15 shows dependences of catalytic conversion of methanol and product selectivities on the reaction time over the example 4c and comparative example 2 zeolites.

[0260] FIG. 16 shows the SEM images of zeolites having framework type MFI synthesized with different ratios of H.sub.2O/Si of example 6.

CITED LITERATURE

[0261] WO 2016/058541 A1 [0262] H. Gies, U. Mller, B. Yilmaz, M. Feyen, T. Tatsumi, H. Imai, H. Zhang, B. Xie, F. S. Xiao, X. Bao, W. Zhang, T. De Baerdemaker, D. De Vos, Chem. Mater. 2012, 24, pp. 2536 [0263] W. Fan, C.-C. Chang, P. Domath, Z. Wang, U.S. Pat. No. 9,108,190 B1, 2015 [0264] L. Ren, Q. Guo, H. Zhang, L. Zhu, C. Yang, L. Wang, X. Meng, Z. Feng, C. Li, F.-S. Xiao, J. Mater. Chem., 2012, 22, pp. 6564 [0265] C.-Y. Hsu, A. S. T Chiang, R. Selvin, R. W. Thompson, J. Phys. Chem. B., 2005, 109, pp. 18813 [0266] C. A. Fyfe, D. H. Brouwer, A. R. Lewis, J.-M. Chezeau, J. Am. Chem. Soc., 2001, 123, pp. 6882 [0267] A. Jomekian, S. Mansoon, B. Bazooyar, A. Moradian, J. Porous Mater., 2012, 19, pp. 979 [0268] R. W. Wang, W. T. Liu, S. Ding, Z. T. Zhang, J. X. Li, S. L. Qiu, Chem. Commun., 2010, 46, 7418.