Effect of temperature in the conversion of methanol to olefins (MTO) using an extruded SAPO-34 catalyst

Abstract

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.

Graphical abstract

Keywords

MTO / SAPO-34 / temperature / extrusion / coke / light alkanes

References

[1] 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

[2] Amghizar I, Vandewalle L A, Van Geem K M, Marin G B. New trends in olefin production. Engineering, 2017, 3(2): 171–178

[3] 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

[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

[6] Stöcker M. Methanol-to-hydrocarbons: Catalytic materials and their behavior. Microporous and Mesoporous Materials, 1999, 29(1-2): 3–48

[7] Weissermel K, Arpe H J. Industrial Organic Chemistry.New York: VCH Publishers Inc., 1997, 13–55

[8] Keil F J. Methanol-to-hydrocarbons: Process technology. Microporous and Mesoporous Materials, 1999, 29(1-2): 49–66

[9] 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

[10] Tian P, Wei Y, Ye M, Liu Z. Methanol to olefins (MTO): From fundamentals to commercialization. ACS Catalysis, 2015, 5(3): 1922–1938

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[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

[29] Leofanti G, Padovan M, Tozzola G, Venturelli B. Surface area and pore texture of catalysts. Catalysis Today, 1998, 41(1-3): 207–219

[30] 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

[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

[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

[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

[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

[36] Ilias S, Bhan A. Mechanism of the catalytic conversion of methanol to hydrocarbons. ACS Catalysis, 2012, 3(1): 18–31

[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

[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

[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

[40] Guisnet M, Magnoux P. Organic chemistry of coke formation. Applied Catalysis A, General, 2001, 212(1-2): 83–96

[41] 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

[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

[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

[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

[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

Acknowledgements

The authors are grateful to the funders of the Industrial Research Chair on Cellulosic Ethanol and Biocommodities at the University of Sherbrooke for their support. The authors would also like to thank MITACS (Grant number ITO3931) for supporting Ignacio Castellanos-Beltran and Gnouyaro palla Assima’s salaries during the project.

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