Process for preparing an arylpropene

Abstract

A process for preparing an arylpropene from a diarylpropane by gas phase thermolysis in the presence of boron containing zeolitic material comprising a membered ring (MR) pore system greater than 10 MR.

Claims

1. A process for preparing a compound of formula (I) ##STR00078## comprising contacting a compound of formula (II) ##STR00079## in the gas phase with a solid catalyst comprising a boron containing zeolitic material comprising a membered ring (MR) pore system greater than 10 MR, wherein k is, independently from each other, 0, 1, 2 or 3; R.sub.1 is, independently from each other, hydroxy, C.sub.1-C.sub.6 alkoxy, di(C.sub.1-C.sub.6-alkyl) aminyl; wherein in the boron containing zeolitic material, the molar ratio of silicon, calculated as elemental silicon, relative to boron, calculated as elemental boron, is in the range of from 1:1 to 100:1.

2. The process of claim 1, wherein the boron containing zeolitic material comprises a 12 MR pore system.

3. The process of claim 1, wherein the MR pore system of the boron containing zeolitic material consists of the 12 MR pore system.

4. The process of claim 1, wherein the MR pore system of the boron containing zeolitic material consists of the 12 MR pore system, wherein the boron containing zeolitic material has framework type BEA.

5. The process of claim 1, wherein the boron containing zeolitic material comprises a 12 MR pore system and a 10 MR pore system, wherein the boron containing zeolitic material has framework type MWW.

6. The process of claim 1, wherein the boron containing zeolitic material consists of the 12 MR pore system and the 10 MR pore system, wherein the boron containing zeolitic material has framework type MWW.

7. The process of claim 1, wherein C.sub.1-C.sub.6 alkoxy is selected from the group consisting of methoxy, ethoxy, n-propoxy, 1-methylethoxy, n-butoxy, 1-methylpropoxy, 2-methylpropoxy, 1,1-dimethylethoxy, n-pentoxy, 1-methylbutoxy, 2-methylbutoxy, 3-methylbutoxy, 1,1-dimethylpropoxy, 1,2-dimethylpropoxy, 2,2-dimethylpropoxy, 1-ethylpropoxy, n-hexoxy, 1-methylpentoxy, 2-methylpentoxy, 3-methylpentoxy, 4-methylpentoxy, 1,1-dimethylbutoxy, 1,2-dimethylbutoxy, 1,3-dimethylbutoxy, 2,2-dimethylbutoxy, 2,3-dimethylbutoxy, 3,3-dimethylbutoxy, 1-ethylbutoxy, 2-ethylbutoxy, 1,1,2-trimethylpropoxy, 1,2,2-trimethylpropoxy, 1-ethyl-1-methylpropoxy, and 1-ethyl-2-methylpropoxy, and wherein in di(C.sub.1-C.sub.6-alkyl) aminyl, the C.sub.1-C.sub.6-alkyl is selected from the group consisting of methyl, ethyl, propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, 2-pentyl, 2-methylbutyl, 3-methylbutyl, 1,2-dimethylpropyl, 1,1-dimethylpropyl, 2,2-dimethylpropyl, 1-ethylpropyl, n-hexyl, 2-hexyl, 2-methylpentyl, 3-methylpentyl, 4-methylpentyl, 1,2-dimethylbutyl, 1,3-dimethylbutyl, 2,3-dimethylbutyl, 1,1-dimethylbutyl, 2,2-dimethylbutyl, 3,3-dimethylbutyl, 1,1,2-trimethylpropyl, 1,2,2-trimethylpropyl, 1-ethylbutyl, 2-ethylbutyl and 1-ethyl-2-methylpropyl.

8. The process of claim 1, wherein the compound of formula (I) is a compound of formula ##STR00080## and the compound of formula (II) is a compound of formula ##STR00081## wherein the compound of formula (I) is a compound of formula ##STR00082## and the compound of formula (II) is a compound of formula ##STR00083##

9. The process of claim 1, wherein in the boron containing zeolitic material, the molar ratio of silicon, calculated as elemental silicon, relative to boron, calculated as elemental boron, is in the range of from 5:1 to 50:1.

10. The process of claim 1, wherein in the boron containing zeolitic material, the molar ratio of silicon, calculated as elemental silicon, relative to boron, calculated as elemental boron, is in the range of from 10:1 to 20:1.

11. The process of claim 1, wherein at least 99 weight % of the boron containing zeolitic material consists of boron, silicon, oxygen, and hydrogen.

12. The process of claim 1, wherein the solid catalyst further comprises a binder material, wherein at least 99.9 weight-% of the binder material consist of silica.

13. The process of claim 1, wherein contacting the compound of formula (II) with the solid catalyst comprising a boron containing zeolitic material is carried out under thermolytic conditions at a temperature of the gas phase in the range of from 250 to 650 C., and at an absolute pressure of the gas phase in the range of from 0.1 to 2.0 bar.

14. The process of claim 1, wherein contacting the compound of formula (II) with the solid catalyst comprising a boron containing zeolitic material is carried out under thermolytic conditions at a temperature of the gas phase in the range of from 300 to 400 C., and at an absolute pressure of the gas phase in the range of from 0.8 to 1.1 bar.

15. The process of claim 1, wherein contacting the compound of formula (II) with the solid catalyst comprising a boron containing zeolitic material is carried out in the presence of a diluent, and wherein the gas phase further comprises a carrier gas.

16. The process of claim 1, wherein contacting the compound of formula (II) with the solid catalyst comprising a boron containing zeolitic material is carried out in continuous mode, at a catalyst load in the range of from 0.01 to 5 kg (compound of formula (II))/kg (catalyst)/h.

17. The process of claim 1, wherein contacting the compound of formula (II) with the solid catalyst comprising a boron containing zeolitic material is carried out in continuous mode, at a catalyst load in the range of from 0.1 to 0.5 kg (compound of formula (II))/kg (catalyst)/h.

18. The process of claim 1, further comprising cooling the reaction mixture, obtained from contacting the compound of formula (II) in the gas phase with the solid catalyst, to a temperature in the range of from 0 to 40 C.

19. The process of claim 1, wherein the compound of formula (I) comprises a compound of formula (I-a) ##STR00084## and a compound of formula (I-b) ##STR00085## said process further comprising separating the compound of formula (I-a) from the compound of formula (I-b), by distillation.

20. The process of claim 2, wherein the compound of formula (I) comprises a compound of formula (I-a) ##STR00086## and a compound of formula (I-b) ##STR00087## said process further comprising separating the compound of formula (I-a) from the compound of formula (I-b), by distillation.

21. A process for increasing the selectivity of solid catalyst gas-phase thermolysis of a compound of formula (II) ##STR00088## with respect to the compound of formula (I-a) ##STR00089## wherein k is, independently from each other, 0, 1, 2 or 3; R.sub.1 is, independently from each other, hydroxy, C.sub.1-C.sub.6 alkoxy, di(C.sub.1-C.sub.6-alkyl) aminyl, which comprises utilizing a boron containing zeolite material comprising a membered ring (MR) pore system greater than 10 MR, wherein in the boron containing zeolitic material, the molar ratio of silicon, calculated as elemental silicon, relative to boron, calculated as elemental boron, is in the range of from 1:1 to 100:1.

Description

EXAMPLES

Reference Example 1: Preparation of Zeolitic Materials

Reference Example 1.1: Preparation of a Boron Containing Zeolitic Material Having Framework Type MWW

(1) A zeolitic material of framework structure type MWW was prepared according to reference example 1.1 of WO 2013/117536 A. This spray-dried zeolitic material having an MWW framework structure had a boron (B) content of 1.9 wt. %, a silicon (Si) content of 41 wt. %, and a total organic carbon (TOC) content of 0.18 wt. %. 150 g of this calcined spray-dried material and 19.75 g Ludoxe AS-40 and 7.5 g Walocel (from Wolf Walsrode), together with 158 ml de-ionized water, were mixed in a kneader (koller) for 1 h. The resulting formable mass was extruded to obtain strands having a diameter of 2 mm. The strands were heated with 3 K/min to a 120 C. and dried at this temperature for 12 h under air. Then, the dried strands were heated with 2 K/min to 500 C. and calcined at that temperature for 5 h under air with an air flow of 80 l/h. The resulting catalyst material had a bulk density of 380 g/l.

Reference Example 1.2: Preparation of a Catalyst Comprising a Boron Containing Zeolitic Material Having Framework Type BEA

(2) A boron-containing zeolitic material was prepared according to Example 6, section 6.1, of WO 2013/117537 A. In a kneader, 15 kg of this boron containing zeolitic material were added. To the zeolitic material, 0.45 kg of HNO.sub.3 (53 weight-%) dissolved in 2 L de-ionized H.sub.2O were added under mixing conditions. The mixture was further mixed for 5 min before 0.75 kg Walocel were added. The material was further mixed for 5 min before 2 kg of Ludox AS-40 were admixed with 3 L of de-ionized H.sub.2O. After another 5 min of mixing, 6 L of de-ionized H.sub.2O are added. After 25 min kneading time, an additional amount of 0.5 L de-ionized H.sub.2O were added, followed, after another 15 min of kneading, by 0.2 L de-ionized H.sub.2O. The resulting paste was extruded in an extrusion press under a pressure of 120-200 bar. The extrudates (strands having a diameter of 2 mm) were dried in an oven at a temperature of 120 C. for 16 h. The calcination was performed in a convection muffle kiln using the following temperature program: 470 min at 470 C., heating to 500 C. in 15 min and keeping the extrudates at this temperature for 300 min. The final strands had a diameter of 2 mm size. The resulting catalyst material had a bulk density of 523 g/l.

Reference Example 1.3: Preparation of a Catalyst Comprising a Boron Containing Zeolitic Material Having Framework Type ZBM-11

(3) 75 kg of a ZBM-11 zeolitic material (a boron containing zeolitic material of mixed framework type MFI and MEL, prepared according example 7 of EP 0 007 081 A, however with a different ratio Si:B) exhibiting a molar ratio of Si relative to B of 18:1 was mixed with 3.75 kg Walocel (from Wolf Walsrode) in a kneader (koller) for 5 min. Then, 6.0 kg NH.sub.4OH was admixed with 12 l de-ionized water, and the mixture was added to the mixture of the zeolitic material and Walocel. After 10 min, 9.9 Ludox AS-40 were added and the resulting mixture was kneaded. After 20 min, 44 l de-ionized water were added. After 50 min, Zusoplast 126/3 (from Zschimmer & Schwarz) were added and further 4 l de-ionized water were added. The kneaded mass was subjected to extrusion under 65-80 bar wherein the extruder was cooled with water during the extrusion process. The extrusion time was in the range of from 15 to 20 min. The power consumption during extrusion was 2.4 A. A die head was employed allowing for producing cylindrical strands having a diameter of 2.0 mm. At the die head out outlet, the strands were not subjected to a cutting to length. The strands were dried at a temperature of 150 C. overnight under air. Then, the dried strands were calcined at a temperature of 650 C. under air in a continuous-type with rotary kiln at an air flow of 100 m.sup.3/h at a material throughput of about 15 kg/h. The resulting catalyst material had a bulk density of 100 g/l.

Reference Example 1.4: Preparation of a Catalyst Comprising a Zeolitic Material Having Framework Type MWW

(4) A zeolitic material of framework structure type MWW was prepared according to example 1.2 of WO 2014/122152 A. This spray-dried zeolitic material having an MWW framework structure had a boron content of 0.08 weight-%, a silicon content of 45 weight-%, a total organic carbon (TOC) content of <0.1 weight-%, and a BET specific surface area determined via nitrogen adsorption at 77 K according to DIN 66131 of 451 m.sup.2/g. 3.5 kg of this calcined spray-dried material was kneaded in a kneader (koller) with 0.226 kg Walocel for 5 min. Then, under kneading conditions, 2.26 kg Ludox AS-40 were added continuously. After 5 min, the addition of de-ionized water (6.0 l) was started. After further 25 min, 0.6 l de-ionized water were added. After a total kneading time of 45 min, the kneaded mass was extrudable. The kneaded mass was subjected to extrusion under 65-80 bar wherein the extruder was cooled with water during the extrusion process. The extrusion time was in the range of from 15 to 20 min. The power consumption during extrusion was 2.4 A. A die head was employed allowing for producing cylindrical strands having a diameter of 2.0 mm. At the die head out outlet, the strands were not subjected to a cutting to length. The strands were dried at a temperature of 120 C. for 12 h under air. Then, the dried strands were calcined at a temperature of 500 C. under air for 5 h. The resulting catalyst material had a bulk density of 348 g/l.

Reference Example 1.5: Preparation of a Catalyst Comprising a Zeolitic Material Having Framework Type BEA

(5) 300 g of a boron-free H-beta zeolitic material exhibiting a molar ratio of Si relative to Al of 12.5:1 (CP814E from Zeolyst) and 39.47 g Ludoxe AS-40 and 10.0 g Walocel (from Wolf Walsrode), were mixed in a kneader (koller) for 10 min. The obtained mass was admixed with 275 ml de-ionized water and kneaded for further 50 min. The resulting formable mass was extruded to obtain strands having a diameter of 2 mm. The strands were heated with 3 K/min to a 120 C. and dried at this temperature for 12 h under air. Then, the dried strands were heated with 2 K/min to 500 C. and calcined at that temperature for 5 h under air with an air flow of 80 l/h. The resulting catalyst material had a bulk density of 420 g/l.

Reference Example 2: Determination of Parameters

Reference Example 2.1: NH3-TPD

(6) The temperature-programmed desorption of ammonia (NH.sub.3-TPD) was conducted in an automated chemisorption analysis unit (Micromeritics AutoChem II 2920) having a thermal conductivity detector. Continuous analysis of the desorbed species was accomplished using an online mass spectrometer (OmniStar QMG200 from Pfeiffer Vacuum). The sample (0.1 g) was introduced into a quartz tube and analyzed using the program described below. The temperature was measured by means of a Ni/Cr/Ni thermocouple immediately above the sample in the quartz tube. For the analyses, He of purity 5.0 was used. Before any measurement, a blank sample was analyzed for calibration. 1. Preparation: Commencement of recording; one measurement per second. Wait for 10 minutes at 25 C. and a He flow rate of 30 cm.sup.3/min (room temperature (about 25 C.) and 1 atm); heat up to 600 C. at a heating rate of 20 K/min; hold for 10 minutes. Cool down under a He flow (30 cm.sup.3/min) to 100 C. at a cooling rate of 20 K/min (furnace ramp temperature); Cool down under a He flow (30 cm.sup.3/min) to 100 C. at a cooling rate of 3 K/min (sample ramp temperature). 2. Saturation with NH.sub.3: Commencement of recording; one measurement per second. Change the gas flow to a mixture of 10% NH.sub.3 in He (75 cm.sup.3/min; 100 C. and 1 atm) at 100 C.; hold for 30 minutes. 3. Removal of the excess: Commencement of recording; one measurement per second. Change the gas flow to a He flow of 75 cm.sup.3/min (100 C. and 1 atm) at 100 C.; hold for 60 minutes. 4. NH.sub.3-TPD: Commencement of recording; one measurement per second. Heat up under a He flow (flow rate: 30 cm.sup.3/min) to 600 C. at a heating rate of 10 K/min; hold for 30 minutes. 5. End of measurement.

(7) Desorbed ammonia was measured by means of the online mass spectrometer, which demonstrates that the signal from the thermal conductivity detector was caused by desorbed ammonia. This involved utilizing the m/z=16 signal from ammonia in order to monitor the desorption of the ammonia. The amount of ammonia adsorbed (mmol/g of sample) was ascertained by means of the Micromeritics software through integration of the TPD signal with a horizontal baseline.

Reference Example 2.2: BET Specific Surface Area

(8) The BET specific surface area values were determined via nitrogen adsorption at 77 K according to DIN 66131.

Example 1: Preparing a Compound of Formula (I) (Anethole) Starting from a Compound of Formula (II) (1,1-bis(4-Methoxyphenyl)Propane)

(9) The first zone (15 cm) of a gas phase oven, equipped with electrical heating means and having an inner diameter of 4 cm, was filled with quartz rings. The downstream zone (20 cm) was then filled with with catalyst strands according to the Reference Examples 1.1 to 1.5. The first 15 cm filled with quartz rings was used as evaporating zone for the dimer and the diluent thereof (water). (The term dimer as used in this context refers to a mixture consisting of 70 mol-% 1,1-bis(4-methoxyphenyl)propane, 28 mol-% 1-(4-methoxyphenyl)-1-(2-methoxyphenyl) propane, and 2 mol-% 1,1-bis(2-methoxyphenyl)propane.) Water was introduced into the reactor as diluent. The dimer and the water were introduced into the evaporation zone as separate streams. As carrier gas, technical nitrogen was used at a volume flow of 20 L/h. The thermolytic reaction was carried out at a temperature of the gas phase of 375 C. (B-MWW, B-BEA, ZBM-11) or 350 C. ([ ]-MWW and BEA), and a catalyst loading of 0.2 kg (dimer)/kg (catalyst)/h. The reaction mixture was condensed in a downstream cooling apparatus at a temperature of 5 C. The water was separated by phase separation, and the resulting organic phase was analyzed by gas chromatography.

(10) The results obtained are given in Table 1 below:

(11) TABLE-US-00001 TABLE 1 Results according to Example 1 Molar BET NH.sub.3-TPD/ Zeolitic material Pore ratio specific surface mmol(NH.sub.3)/g Conv. Select. Select. (ref. ex. #) system/MR Si/B area/m.sup.2/g (zeolitic material) dimer .sup.1)/% (I) .sup.2)/% (I-a) .sup.3)/% B-MWW (1.1) 10 + 12 14 448 0.37 88.4 92.2 58.2 B-BEA (1.2) 12 14 498 0.30 68.5 79.7 59.5 ZBM-11 (1.3) 10 18 380 0.37 <20 0 0 [ ]-MWW .sup.4) (1.4) 10 + 12 >200 462 0.04 0 0 0 BEA (1.5) 12 500 1.08 68.4 74.5 53.3 .sup.1) Conversion of the dimer (1,1-bis(4-methoxyphenyl)propane plus 1-(4-methoxyphenyl)-1-(2-methoxyphenyl)propane plus 1,1-bis(2-methoxyphenyl)propane). .sup.2) Selectivity (I) is defined as the sum of the molar amounts of the compounds of formula (I-a) and the para-substituted cis-isomer of formula (I-b), divided by the molar amount of converted dimer (1,1-bis(4-methoxyphenyl)propane plus 1-(4-methoxyphenyl)-1-(2-methoxyphenyl)propane plus 1,1-bis(2-methoxyphenyl)propane). .sup.3) Selectivity (I-a) is defined as the molar amount of the compound of formula (I-a) divided by the molar amount of converted dimer (1,1-bis(4-methoxyphenyl)propane plus 1-(4-methoxyphenyl)-1-(2-methoxyphenyl)propane plus 1,1-bis(2-methoxyphenyl)propane). .sup.4) The abbreviation [ ]-MWW describes the deboronated zeolite of framework type MWW.

(12) Results

(13) From the examples, it can be seen that a boron containing zeolitic material having a 10 MR pore system (ZBM-11) is not active as a catalyst in the above-discussed reaction whereas a boron containing zeolitic material having a pore system of greater than 10 (B-MWW: 12 MR; B-BEA: 12 MR) is active.

(14) As can be seen from the comparison of a zeolitic material having a 12 MR pore system which, however, does not contain a substantial amount of boron ([ ]-MWW), and the B-MWW material, the presence of a sufficient amount of boron is mandatory to render the zeolitic material having a pore system of greater than 10 MR an active catalyst in the above-discussed reaction.

(15) The influence of boron is also shown by the comparison of a boron-free zeolitic material having a pore system greater than 10 MR (BEA, 12 MR) and the respective boron containing zeolitic material (B-BEA): in particular with respect to the most decisive parameter, the selectivity with regard to the valuable product, an increase from 74.5% to 79.7% could be achieved, i.e. an improvement in selectivity of about 7%.

(16) In particular, it was shown that the yield with regard to the compound of formula (I-a) (in %), calculated as the selectivity (I-a) times the conversion dimer, is very high for B-BEA (41.1%), and even higher for B-MWW.

(17) Cited Prior Art CN 102491884 A SU 261380 SU 355144 Maslozhirovaya Promyshlennost (1974), volume 9, pages 29-30 CN 103058835 A DE 2418974 B1 WO 2013/117536 A WO 2013/117537 A WO 2014/122152 A EP 0 007 081 A