The methanol-to-olefin (MTO) reaction was investigated in a bench-scale, fixed-bed reactor using an extruded catalyst composed of a commercial SAPO-34 (65 weight percentage, wt-%) embedded in an amorphous SiO2 matrix (35 wt-%). The texture properties, acidity and crystal structure of the pure SAPO-34 and its extruded form (E-SAPO-34) were analyzed and results indicated that the extrusion step did not affect the properties of the catalyst. Subsequently, E-SAPO-34 was tested in a temperature range between 300 and 500 °C, using an aqueous methanol mixture (80 wt-% water content) fed at a weight hour space velocity (WHSV) of 1.21 h−1. At 300 °C, a low conversion was observed combined with catalyst deactivation, which was ascribed to oligomerization and condensation reactions. The coke analysis showed the presence of diamandoid hydrocarbons, which are known to be inactive molecules in the MTO process. At higher temperatures, a quasi-steady state was reached during a 6 h reaction where the optimal temperature was identified at 450 °C, which incidentally led to the lowest coke deposition combined with the highest H/C ratio. Above 450 °C, surges of ethylene and methane were associated to a combination of H-transfer and protolytic cracking reactions. Finally, the present work underscored the convenience of the extrusion technique for testing catalysts at simulated scale-up conditions.
. [J]. Frontiers of Chemical Science and Engineering, 2018, 12(2): 226-238.
Ignacio Jorge Castellanos-Beltran, Gnouyaro Palla Assima, Jean-Michel Lavoie. Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst. Front. Chem. Sci. Eng., 2018, 12(2): 226-238.
Bellussi G, Pollesel P. Industrial applications of zeolite catalysis: Production and uses of light olefins. Studies in Surface Science and Catalysis, 2005, 158(2): 1201–1212 https://doi.org/10.1016/S0167-2991(05)80466-5
Mokrani T, Scurrell M. Gas conversion to liquid fuels and chemicals: The methanol route—catalysis and processes development. Catalysis Reviews, 2009, 51(1): 1–145 https://doi.org/10.1080/01614940802477524
4
Plotkin J S. The changing dynamics of olefin supply/demand. Catalysis Today, 2005, 106(1): 10–14
5
Chen X, Yan Y. Study on the technology of thermal cracking of paraffin to alpha olefins. Journal of Analytical and Applied Pyrolysis, 2008, 81(1): 106–112 https://doi.org/10.1016/j.jaap.2007.09.009
6
Stöcker M. Methanol-to-hydrocarbons: Catalytic materials and their behavior. Microporous and Mesoporous Materials, 1999, 29(1-2): 3–48 https://doi.org/10.1016/S1387-1811(98)00319-9
7
Weissermel K, Arpe H J. Industrial Organic Chemistry.New York: VCH Publishers Inc., 1997, 13–55
Chen J Q, Bozzano A, Glover B, Fuglerud T, Kvisle S. Recent advancements in ethylene and propylene production using the UOP/Hydro MTO process. Catalysis Today, 2005, 106(1-4): 103–107 https://doi.org/10.1016/j.cattod.2005.07.178
10
Tian P, Wei Y, Ye M, Liu Z. Methanol to olefins (MTO): From fundamentals to commercialization. ACS Catalysis, 2015, 5(3): 1922–1938 https://doi.org/10.1021/acscatal.5b00007
11
Inui T, Phatanasri S, Matsuda H. Highly selective synthesis of ethene from methanol on a novel nickel-silicoaluminophosphate catalyst. Journal of the Chemical Society. Chemical Communications, 1990, 20(1): 205–206 https://doi.org/10.1039/C39900000205
12
Inui T. European Patent, 0418142B1, 1990-09-11
13
Wilson S, Barger P. The characteristics of SAPO-34 which influence the conversion of methanol to light olefins. Microporous and Mesoporous Materials, 1999, 26(1-2): 117–126 https://doi.org/10.1016/S1387-1811(98)00325-4
14
Chen D, Moljord K, Holmen A. A methanol to olefins review: Diffusion, coke formation and deactivation on SAPO type catalysts. Microporous and Mesoporous Materials, 2012, 164(1): 239–250 https://doi.org/10.1016/j.micromeso.2012.06.046
15
Wu X, Anthony R G G. Effect of feed composition on methanol conversion to light olefins over SAPO-34. Applied Catalysis A, General, 2001, 218(1-2): 241–250 https://doi.org/10.1016/S0926-860X(01)00651-2
16
Wolthuizen J P, Van den Berg J P, Van Hooff J H C. Low temperature reactions of olefins on partially hydrated zeolite H-ZSM-5. Studies in Surface Science and Catalysis, 1980, 5(1): 85–92 https://doi.org/10.1016/S0167-2991(08)64868-5
17
Müller S, Liu Y, Kirchberger F M, Tonigold M, Sanchez-Sanchez M, Lercher J A. Hydrogen transfer pathways during zeolite catalyzed methanol conversion to hydrocarbons. Journal of the American Chemical Society, 2016, 138(49): 15994–16003 https://doi.org/10.1021/jacs.6b09605
18
Chen D, Rebo H P, Grønvold A, Moljord K, Holmen A. Methanol conversion to light olefins over SAPO-34: Kinetic modeling of coke formation. Microporous and Mesoporous Materials, 2000, 35-36: 121–135 https://doi.org/10.1016/S1387-1811(99)00213-9
19
Dahl I M, Kolboe S. On the reaction mechanism for hydrocarbon formation from methanol over SAPO-34. Journal of Catalysis, 1996, 161(1): 304–309 https://doi.org/10.1006/jcat.1996.0188
20
Olsbye U, Bjørgen M, Svelle S, Lillerud K P, Kolboe S. Mechanistic insight into the methanol-to-hydrocarbons reaction. Catalysis Today, 2005, 106(1-4): 108–111 https://doi.org/10.1016/j.cattod.2005.07.135
21
Haw J F, Song W, Marcus D M, Nicholas J B. The mechanism of methanol to hydrocarbon catalysis. Accounts of Chemical Research, 2003, 36(5): 317–326 https://doi.org/10.1021/ar020006o
22
Michels N L, Mitchell S, Pérez-Ramírez J. Effects of binders on the performance of shaped hierarchical MFI zeolites in methanol-to-hydrocarbons. ACS Catalysis, 2014, 4(8): 2409–2417 https://doi.org/10.1021/cs500353b
23
Freiding J, Patcas F C, Kraushaar-Czarnetzki B. Extrusion of zeolites: Properties of catalysts with a novel aluminium phosphate sintermatrix. Applied Catalysis A, General, 2007, 328(2): 210–218 https://doi.org/10.1016/j.apcata.2007.06.017
24
Cui Y, Zhang Q, He J, Wang Y, Wei F. Pore-structure-mediated hierarchical SAPO-34: Facile synthesis, tunable nanostructure, and catalysis applications for the conversion of dimethyl ether into olefins. Particuology, 2013, 11(4): 468–474 https://doi.org/10.1016/j.partic.2012.12.009
25
Schmidt F, Paasch S, Brunner E, Kaskel S. Carbon-templated SAPO-34 with improved adsorption kinetics and catalytic performance in the MTO reaction. Microporous and Mesoporous Materials, 2012, 164(1): 214–221 https://doi.org/10.1016/j.micromeso.2012.04.045
26
Yang S T, Kim J Y, Chae H J, Kim M, Jeong S Y, Ahn W S. Microwave synthesis of mesoporous SAPO-34 with a hierarchical pore structure. Materials Research Bulletin, 2012, 47(11): 3888–3892 https://doi.org/10.1016/j.materresbull.2012.08.041
27
Sun Q, Ma Y, Wang N, Li X, Xi D, Xu J, Deng F, Yoon K B, Oleynikov P, Terasaki O, Yu J. High performance nanosheet-like silicoaluminophosphate molecular sieves: Synthesis, 3D EDT structural analysis and MTO catalytic studies. Journal of Materials Chemistry. A, Materials for Energy and Sustainability, 2014, 2(42): 17828–17839 https://doi.org/10.1039/C4TA03419H
28
Wang C, Yang M, Tian P, Xu S, Yang Y, Wang D, Yuan Y, Liu Z. Dual template-directed synthesis of SAPO-34 nanosheet assemblies with improved stability in the methanol to olefins reaction. Journal of Materials Chemistry. A, Materials for Energy and Sustainability, 2015, 3(10): 5608–5616 https://doi.org/10.1039/C4TA06124A
Al-Dughaither A S, De Lasa H. Neat dimethyl ether conversion to olefins (DTO) over HZSM-5: Effect of SiO2/Al2O3 on porosity, surface chemistry, and reactivity. Fuel, 2014, 138(1): 52–64 https://doi.org/10.1016/j.fuel.2014.07.026
31
Magnoux P, Roger P, Canaff C, Fouche V, Gnep N S, Guisnet M. New technique for the characterization of carbonaceous compounds responsible for zeolite deactivation. In: Proceedings of the 4th International Symposium. Amsterdam: Elsevier, 1987, 317–330
32
Gayubo A G, Aguayo A T, Sánchez del Campo A E, Tarrío A M, Bilbao J. Kinetic modeling of methanol transformation into olefins on a SAPO-34 catalyst. Industrial & Engineering Chemistry Research, 2000, 39(2): 292–300 https://doi.org/10.1021/ie990188z
33
Prakash A M, Unnikrishnan S. Synthesis of SAPO-34: High silicon incorporation in the presence of morpholine as template. Journal of the Chemical Society, Faraday Transactions, 1994, 90(15): 2291–2296 https://doi.org/10.1039/ft9949002291
34
Mores D, Stavitski E, Kox M H F F, Kornatowski J, Olsbye U, Weckhuysen B M. Space-and time-resolved in-situ spectroscopy on the coke formation in molecular sieves: Methanol-to-olefin conversion over H-ZSM-5 and H-SAPO-34. Chemistry (Weinheim an der Bergstrasse, Germany), 2008, 14(36): 11320–11327 https://doi.org/10.1002/chem.200801293
35
Hereijgers B P C, Bleken F, Nilsen M H, Svelle S, Lillerud K P, Bjørgen M, Weckhuysen B M, Olsbye U. Product shape selectivity dominates the methanol-to-olefins (MTO) reaction over H-SAPO-34 catalysts. Journal of Catalysis, 2009, 264(1): 77–87 https://doi.org/10.1016/j.jcat.2009.03.009
36
Ilias S, Bhan A. Mechanism of the catalytic conversion of methanol to hydrocarbons. ACS Catalysis, 2012, 3(1): 18–31 https://doi.org/10.1021/cs3006583
37
Hutchings G J, Hunter R. Hydrocarbon formation from methanol and dimethyl ether: A review of the experimental observations concerning the mechanism of formation of the primary products. Catalysis Today, 1990, 6(3): 279–306 https://doi.org/10.1016/0920-5861(90)85006-A
38
Salehirad F, Anderson M W. Solid-state 13C MAS NMR study of methanol-to-hydrocarbon chemistry over H-SAPO-34. Journal of Catalysis, 1996, 314(2): 301–314 https://doi.org/10.1006/jcat.1996.0386
39
Wei Z, Chen Y, Li J, Wang P, Jing B, He Y, Dong M, Jiao H, Qin Z, Wang J, Fan W. Methane formation mechanism in the initial methanol-to-olefins process catalyzed by SAPO-34. Catalysis Science & Technology, 2016, 6(14): 5526–5533 https://doi.org/10.1039/C6CY00506C
Sanati M, Hörnell C, Järäs S G. The oligomerization of alkenes by heterogeneous catalysts. Catalysis, 1999, 14(7): 236–287
42
Kotrel S, Knözinger H, Gates B C. The Haag-Dessau mechanism of protolytic cracking of alkanes. Microporous and Mesoporous Materials, 2000, 35-36: 11–20 https://doi.org/10.1016/S1387-1811(99)00204-8
43
Elliott D C. Relation of reaction, time and temperature to chemical composition of pyrolysis oils. In: Soltes E J, Milne T A, eds. Pyrolysis Oils from Biomass, 1988, Chapter 6: 55–65
44
Wei Y, Li J, Yuan C, Xu S, Zhou Y, Chen J, Wang Q, Zhang Q, Liu Z. Generation of diamondoid hydrocarbons as confined compounds in SAPO-34 catalyst in the conversion of methanol. Chemical Communications, 2012, 48(1): 3082–3084 https://doi.org/10.1039/c2cc17676a
45
Magnoux P, Rabeharitsara A, Cerqueira H S. Influence of reaction temperature and crystallite size on HBEA zeolite deactivation by coke. Applied Catalysis A, General, 2006, 304(1): 142–151 https://doi.org/10.1016/j.apcata.2006.02.040
46
Vedrine J C, Dejaifve P, Garbowski E D, Derouane E G. Aromatics formation from methanol and light olefins conversions on H-ZSM-5 zeolite: Mechanism and intermediate species. Studies in Surface Science and Catalysis, 1980, 5(1): 29–37 https://doi.org/10.1016/S0167-2991(08)64862-4
47
Luo M, Zang H, Hu B, Wang B, Mao G. Evolution of confined species and their effects on catalyst deactivation and olefin selectivity in SAPO-34 catalyzed MTO process. RSC Advances, 2016, 6(1): 17651–17658 https://doi.org/10.1039/C5RA22424A