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Toluene Methylation by Methyl Mercaptan and Methanol over Zeolites – A Comparative Study Claudia Cammarano, Elodie Gay, Annie Finiels, François Fajula, and Vasile Hulea ACS Catal., Just Accepted Manuscript • DOI: 10.1021/acscatal.8b04608 • Publication Date (Web): 18 Dec 2018 Downloaded from http://pubs.acs.org on December 18, 2018
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ACS Catalysis
Toluene Methylation by Methyl Mercaptan and Methanol over Zeolites – A Comparative Study Claudia Cammarano, Elodie Gay, Annie Finiels, François Fajula and Vasile Hulea* Institut Charles Gerhardt Montpellier, UMR 5253, CNRS-UM-ENSCM, Matériaux Avancés pour la Catalyse et la Santé, 240 avenue du Professeur Emile Jeanbrau, CS 60297, 34296 Montpellier Cedex 5, France ABSTRACT: In this study, we show that the Friedel-Crafts (FC) alkylation of aromatic hydrocarbons by thiols to form C-C bond is feasible. The gas phase reaction between toluene and CH3SH catalyzed by HZSM-5 zeolite was chosen as model reaction. In the temperature range of 350 - 550 °C, the alkylation of toluene to produce xylenes was the main reaction involved in the process. The reaction between toluene and CH3SH was compared with the well-known reaction between toluene and CH3OH. Significant similarities exist, notably the ability of both CH3SH and CH3OH to generate methoxonium species on the zeolite surface and to methylate the aromatic ring in a typical FC process. The maximum alkylation yield of 41% for CH3OH was reached at 350 °C, while that of 67.3% for CH3SH was reached at 450 °C. This difference in temperature can be correlated with the energy barriers required for the formation of methoxonium species, i.e. 24.6 kcal/mol (CH3OH) and 26.4 kcal/mol (CH3SH). The high performance in alkylation proved by CH3SH was attributed to its lower consumption in the side reactions, i.e. the formation of light hydrocarbons.
KEYWORDS: C-C coupling, electrophilic substitution, heterogeneous catalysis, thiols, zeolites
The Friedel-Crafts (FC) alkylation is one of the oldest and most important C-C bond forming reactions.1,2 This catalytic reaction, performed in both liquid and gas phase, continues to be an attractive method for preparing valuable alkyl substituted arenes.3-8 Typically, FC alkylation occurs between the C-H bond in an aromatic substrate and a carbocation. The carbocations are generated in the presence of an acid catalyst, from various precursors, including alkyl halides, esters, alkenes, alkynes, alcohols, etc.9 The sulfur analogues of alcohols are the thiols (RSH). Surprisingly, despite the similarities between alcohols and thiols, there is no report in the literature focused on the electrophilic attack of RSH itself on aromatic rings. Only a theoretical study about the benzene methylation by methyl mercaptan over a zeolite catalyst has been recently published by our group.10 Note that reactions between the aromatic and sulfur compounds were widely investigated during the last decades. But the aim was to generate C-S bonds, mostly for preparing biologically and pharmaceutically active molecules. Thus, in transition-metal-catalyzed processes (metal = Pd, Cu, Ni), the aryl C-halogen or C-H bonds reacted with sulfur nucleophiles, such as thiols and disulfides to produce aryl sulfides.11-15 As known, sulfur is less basic than oxygen, and as a result the thiols are more easily involved in nucleophilic substitutions than the alcohols.16 In this study we report the first experimental results proving the C-C bond formation in the reaction between an aromatic hydrocarbon (toluene) and a thiol (CH3SH) catalyzed by an acid solid catalyst (HZSM-5 zeolite). This reaction is compared with the well-known reaction between toluene and methanol.17-24 The goal is to supply suitable answers to two
rational questions: (i) is methyl mercaptan capable to methylate the aromatic ring in a FC process? (ii) what similarity can be drawn between methylmercaptan and methanol in such a reaction? CH3SH is an industrial waste gas and an abundant contaminant in natural gas. Conventional industrial processes for CH3SH removal transform it into dimethyl disulfide, which has not found qualified applications. Therefore, there are real economic and ecological benefits to develop new methods for catalytically converting CH3SH into value added molecules. Our previous studies have already shown that CH3SH can be successfully converted to CH4 and H2S at 550 °C in the presence of protonic zeolites.25-27 The reactions between toluene (T) and CH3SH or CH3OH have been carried out at 250, 350, 450 and 550 °C, in a fixed bed flow microreactor, using HZSM-5 zeolite as catalyst (Si/Al = 15, SBET = 350 m2g-1, acidity = 1.09 mmolg-1 (ammonia TPD between 175 and 600 °C)). HZSM-5 is known to be very efficient and stable in reactions involving aromatic hydrocarbons and/or methanol. It is widely used in many petrochemical processes and other industrial applications. 28-33 For both reactions the nature and the amount of the products notably varied when the temperature increased from 250 to 550 °C (see Figure S1 in Supporting Information). Based on the experimental results, we listed in Table 1 the main reactions involved in the formation of different products, as well as the associated temperature ranges. Two general remarks can be done: (i) similar homologous reactions occurred when CH3SH and CH3OH were used as alkylating agents and (ii) the reactions involving CH3SH occurred at higher temperatures than the homologues reactions involving CH3OH.
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Table 1. Main reactions involved in the processes and related temperature range Reactions
Temperature range
Alkylation reactions : T + CH3SH → X + TMB + H 2S T + CH3OH → X + TMB + H2O
≥ 350 °C ≥ 250 °C
Reactions involving only CH3SH or CH3OH: 2CH3SH → CH3SCH3 + H2S CH3SH → C1-C3 + H2S 2CH3OH → CH3OCH3 + H2O CH3OH → C1-C3 + H2O CH3SH → Hydrocarbons + CS2 + H2S
≥ 250 °C ≥ 450 °C ≥ 250 °C ≥ 350 °C ≥ 450 °C
Toluene disproportionation 2T → B + X
≥ 450 °C
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formation in these reactions. The molar compositions of the aromatic fractions (B, T, X, TMB) are summarized in Table S1 (Supporting Information). Table 2. Selectivity in alkylation and toluene conversion at different temperatures Toluene conversion (%) Totalb Alkyl.c Disprop.d
Reagents
T (°C) Salkyla
T+ CH3SH
250 350 450 550
100 94.3 98.2 72.4
2.0 21.0 68.5 47.4
2.0 19.8 67.3 34.3
0 1.2 1.2 13.1
T+ CH3OH
250 350 450 550
100 95.1 89.3 72.3
10.5 43.1 45.1 50.5
10.5 41.0 40.5 38.9
0 2.1 4.6 14.9
a
In the catalytic process involving T and CH3SH, dimethyl sulfide (CH3SCH3) and H2S were the major products at 250 and 350 °C. CH3SCH3 is directly derived from CH3SH by a condensation reaction, as we have previously shown.25 Almost no light hydrocarbons were formed in this temperature range. Some amounts of xylenes (X) and trimethylbenzenes (TMB) resulted from toluene alkylation at 350 °C, but the intrinsic selectivity in toluene methylation dominated at 450 °C. The reactions leading to C1-C3 hydrocarbons, and the toluene disproportionation to benzene (B) and xylenes principally occurred at 550 °C. Small amount of CS2 was also produced at high temperature (Figure S2, Supporting Information). The absence of C6+ aliphatics and C3-C4 alkanes indicates that the production of aromatics from CH3SH, via olefins and hydrogen transfer reactions,34 is insignificant during the toluene methylation reaction. Note that, in all catalytic tests, no notable change in activity and selectivity was observed during the 4h on stream. The most important reaction for this study was the toluene alkylation by CH3SH towards xylenes. The toluene conversion in this reaction became significant above 350 °C, and was accompanied by several sequential and parallel reactions, including further alkylation of xylenes, toluene disproportionation and light hydrocarbons formation (Scheme 1). These reactions also occurred in the catalytic tests involving T and methanol. Scheme 1. Reactions involving toluene and CH3EH (E = O or S) C1, C2, C3
CH3EH
CH3EH
Data in Table 2 and Table 3 give an overview on the quantitative aspects about the reagents consumption and the products
Selectivity in alkylation: 100 x (X + TMB - B)/(B + X + TMB); b percentage of converted toluene over toluene reactant: 100 x (B + X + TMB)/(B + T + X + TMB); c conversion in alkylation: 100 x (X + TMB)/(B + T + X + TMB); d conversion in disproportionation: 100 x B/(B + T + X + TMB).
The conversion of CH3SH became significant only above 350 °C. In contrast, full conversion of CH3OH was noticed over the temperature range of 250-550 °C. For each temperature, the conversion of the alkylating agents (CH3EH, E = S or O) was superior than that of toluene. Table 3. CH3EHa conversion and relative products distribution Reagents T+ CH3SH
T+ CH3OH a
T (°C) 250 350 450 550
Total 21.0 68.0 93.0 99.0
250 350 450 550
97.0 100 100 100
CH3EH conversion (%) (CH3)2E alkyl.b C1-C3c 19.0 2.0 0 41.5 25.0 1.5 2.0 79.5 11.5 0 37.0 62.0 65.0 10.0 0 0
10.6 44.8 42.5 40.3
21.6 55.2 57.5 59.7
E = S or O; b in toluene alkylation; c % in C1-C3 formation
The main alkylation products were the xylenes, but some amounts of TMB were formed. The isomer fractions in xylenes were very close to the thermodynamic equilibrium.35 Thus, (m+p)-xylene represents 76-78% and o-xylene represents 22-24%. High reaction temperature (550 °C) favors the toluene disproportionation, which simultaneously decreases the rate of the xylene formation. As shown in Table 3, the product stream contained C1, C2 and C3 hydrocarbons, which are produced through reaction involving CH3EH. Confirming the results previously reported, the major components of light hydrocarbons were C2 and C3 at temperatures lower than 450 °C17-24,36 and CH4 at 550 °C.25-27 To a better comparison of CH3SH and CH3OH, the yields of alkylation products obtained at different temperatures were plotted in Figure 1. These values were calculated by multiplying the overall toluene conversion by the toluene selectivity in alkylation (Table 2).
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Yield,%
60
40
20
0 250
350
450
550
Temperature,°C
Figure 1. Yield in alkylation as a function of temperature (based on the aromatics balance); black bar = CH3SH, grey bar = CH3OH; yield = Salkylation x ConvTol; Salkylation = (X + TMB -B)/( X + TMB + B); ConvTol = 100x(B + X + TMB)/(B + T + X + TMB)
Similar to the overall toluene conversion, the yield in alkylation to X and TMB first increased with increasing reaction temperature and reached a maximum at 350 °C and 450 °C for CH3OH and CH3SH, respectively. Note that, at low temperature, the alkylation ability of CH3OH was higher than that of CH3SH. But it must be underlined that the maximum alkylation yield was 67.3% with CH3SH and only 41.0% with CH3OH. The drop in yield at 550 °C for both reagents is mainly due to the considerable consumption of toluene through disproportionation. The difference between CH3OH and CH3SH observed at intermediate and high temperature can be correlated with the consumption of CH3EH in the side reactions, as shown in Table 3. The inefficient "methanol usage", i.e. the percentage of CH3OH not implicated in aromatics alkylation, over overall conversion of CH3OH, is known to be a major drawbacks for the toluene methylation over zeolites.19,36 Typically, this parameter was about 50%. The utilization of CH3EH (E = S, O) in our catalytic tests, expressed as percentage of converted CH3EH into xylene and trimethylbenzenes over overall conversion of CH3EH, are plotted in Figure 2.
Knowing that CH3OCH3 is an efficient alkylating agent, the conversion of methanol into CH3OCH3, as well as that of CH3SH into CH3SCH3 have not been taken into account in these quantitative evaluations. Significant differences exist between the two alkylating agents, in particular at 350 and 450 °C, which are the two most favourable temperatures for the alkylation process. The efficient use of methanol was 43±2%. In contrast, CH3SH showed values up to 97% at 350 °C and 80% at 450 °C, proving its remarkable efficiency for toluene alkylation. At 550 °C, 65 % of mercaptan converted to methane and only 35% was used for the toluene methylation. In summary, although in terms of usage and reactivity some differences exist between CH3SH and CH3OH, in general both molecules showed comparable behaviours in the toluene alkylation over ZSM-5. Consequently, it is reasonable to consider that the main steps involved in the reaction mechanisms are similar. The aromatic alkylation with methanol has been intensively investigated during the last decades. Two reaction mechanisms are accepted for this process: (i) concerted mechanism, in which methanol and aromatic are co-adsorbed on a single acid site and react in a concerted step, and (ii) stepwise mechanism, in which methanol dehydrates on an acid site to form a surface-bound methoxide species, which then methylates aromatics in an Eley-Rideal-type mechanism. Spectral and kinetic experiments showed that the surface methoxide species are very likely involved as key reactive intermediates in the methanol conversion and methylation processes by methanol on zeolite catalysts.37-41 Accordingly, the toluene methylation with methanol over ZSM-5 follows a pathway, as depicted in Scheme 2a. The three main steps of this mechanism are: (i) adsorption of CH3OH on a Brønsted proton; (ii) dehydration of methanol to form surface-bound methoxy species (-OCH3) and (iii) interaction of the methoxy function with toluene in the mobile phase (adsorbed or not) to form xylene, which then desorbs from the zeolite surface. Scheme 2. Step-wise mechanisms for methylation of aromatics on zeolites with CH3OH (a) and CH3SH (b) CH3 OH (a)
100
H CH3 OH +
O Si
80 CH3EH usage, %
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ACS Catalysis
H
O Al
Si
(i)
O Si
Al
CH3
- H2 O
O Si
(ii)
O Si
+
O Al
H (iii)
Si
+
O Si
O Al
Si
CH3 SH (b)
60
H CH3 SH +
O Si
40 20 0 250
350
450
550
Temperature,°C
Figure 2. Percentage of CH3EH (E = S, O) used for the methylation of toluene; black bar = CH3SH, grey bar = CH3OH
H
O Al
O Si
Si
CH3
- H2 S
O
O Al
Si
Si
O Al
+
H +
Si
O Si
O Al
Si
In a recent theoretical study we compared methanol and methyl mercaptan as methylating agents through a step-wise mechanism.10 Accordingly, the pathway of the methylation of toluene by CH3SH (represented in Scheme 2b) is similar to that of methanol (Scheme 2a). The calculated adsorption energies for the methanol and methyl mercaptan on HZSM5 were 28.18 and -17.32 kcal/mol, respectively. A similar behavior has been reported by Soscun et al.42 This means that the adsorption of the sulfur compound is less favoured than that of the oxygenated alcohol, which can be
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rationalized from the differences in the electronic nature of the S and O atoms. For the next step, i.e. CH3OH dehydration and CH3SH desulfurization, the energy barriers were 24.6 and 26.4 kcal/mol, respectively.42 These values are close, suggesting that CH3SH is also capable to generate methoxonium species on the zeolite surface. On the other hand, this difference en energy barrier justifies the difference in temperature between the two processes. In conclusion, we have demonstrated for the first time that CH3SH is an efficient methylating agent, able to convert selectively toluene into xylenes by a Friedel-Crafts mechanism. The behaviour of CH3SH was mechanistically analogous, but superior in term of efficiency to that exhibited by CH3OH in the reaction with toluene. Reactions between T and CH3SH catalyzed by HZSM-5 zeolite yielded up to 67 % of methylated aromatics. Consistent with computational studies, the optimum temperature for T alkylation with CH3SH was higher than that observed for the T alkylation with CH3OH (450 °C vs. 350 °C). The high efficiency proved by CH3SH was mainly attributed to its lower consumption in the side reactions, i.e. the formation of light hydrocarbons. About a possible outlet of this study into an industrial application, the results may be very useful in designing a viable process for cleaning natural gas. Thus, the alkylation of toluene with CH3SH into xylenes and H2S over H-zeolites, could be incorporated, as a central stage, into an integrated system comprising well-known technologies, such as the adsorption of mercaptans on solids43 and the absorption of H2S with conventional solvents. Note that, in the commercial processes used for the production of the aromatics BTX, toluene is overproduced relative to the current market demand. The surplus toluene should be converted to a more valuable xylene via methylation processes with CH3SH.
ASSOCIATED CONTENT Supporting Information. Experimental details of the synthesis and characterization of the catalysts. This material is available free of charge via the Internet at http://pubs.acs.org.
AUTHOR INFORMATION Corresponding Author *E-mail:
[email protected] Notes The authors declare no competing financial interest
This paper is dedicated to Professor Emil Dumitriu
ACKNOWLEDGEMENTS This work was supported by CNRS and ENSCM, France.
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REFERENCES (1) Friedel, C; Crafts, J. M. A New General Synthetical Method of Producing Hydrocarbons. J. Chem. Soc. 1877, 32, 725-791. (2) Olah, G. A. Friedel-Crafts Chemistry, Wiley, New York, 1973 (3) Weissermel, K.; Arpe, H. J. Industrial Organic Chemistry, Completely Revised 4th ed., Wiley-VCH: Weinheim, 2003. (4) Franck, H. G.; Stadelhofer, J. W. Industrial Aromatic Chemistry, Springer-Verlag, Berlin Heidelberg, 1988. (5) Cejka, J.; Wichterlova, B. Acid-Catalyzed Synthesis of Mono- and Dialkyl Benzenes over Zeolites: Active Sites, Zeolite Topology, and Reaction Mechanisms. Catal. Rev.-Sci. Eng. 2002, 44, 375-421. (6) Perego, C.; Ingallina, P. Recent Advances in the Industrial Alkylation of Aromatics: New Catalysts and New Processes. Catal. Today 2002, 73, 3–22. (7) Al-Khattaf, S.; Ali, S. A.; Aitani, A. M.; Zilkova, N.; Kubicka, D.; Cejka, J. Recent Advances in Reactions of Alkylbenzenes over Novel Zeolites: The Effect of Zeolite Structure and Morphology. Catal. Rev. -Sci. Eng. 2014, 56, 333-402. (8) Yang, W.; Wang, Z.; Sun, H.; Zhang, B. Advances in Development and Industrial Applications of Ethylbenzene Processes. Chin. J. Catal. 2016, 37, 16–26. (9) Taylor, R. Electrophilic Aromatic Substitution, John Wiley & Sons, New York, 1990, pp. 187. (10) Reina, M.; Martinez, A.; Cammarano, C.; Leroi, C.; Hulea, V.; Mineva, T. Conversion of Methyl Mercaptan to Hydrocarbons over H-ZSM-5 Zeolite: DFT/BOMD Study. ACS Omega 2017, 2, 46474656. (11) Iwasaki, M.; Iyanaga, M.; Tsuchiya, Y.; Nishimura, Y.; Li, W.; Li, Z.; Nishihara, Y. Palladium-Catalyzed Direct Thiolation of Aryl C-H Bonds with Disulfides. Chem. Eur. J. 2014, 20, 2459-2462. (12) Fernandez-Rodrıguez, M. A.; Shen, Q.; Hartwig, J. F. A General and Long-Lived Catalyst for the Palladium-Catalyzed Coupling of Aryl Halides with Thiols. J. Am. Chem. Soc. 2006, 128, 2180-2181. (13) Beletskaya, I. P.; Ananikov, V. P. Transition-Metal-Catalyzed C−S, C−Se, and C−Te Bond Formation via Cross-Coupling and Atom-Economic Addition Reactions. Chem. Rev. 2011, 111, 15961636. (14) Kazemi, M.; Shiri, L.; Kohzadi, H. Recent Advances in Aryl Alkyl and Dialkyl Sulfide Synthesis. Phosphorus Sulfur Silicon Relat. Elem. 2015, 190, 978-1003. (15) Shen, C.; Zhang, P.; Sun, Q.; Bai, S.; Hor, T. S. A.; Liu, X. Recent Advances in C–S Bond Formation via C–H Bond Functionalization and Decarboxylation. Chem. Soc. Rev. 2015, 44, 291-314. (16) Oae, S. Organic Sulfur Chemistry: Structure and Mechanism, CRC Press, Boca Raton, 1991. (17) Kaeding, W.; Chu, C.; Young, L.; Weinstein, B.; Butter, S. Selective Alkylation of Toluene with Methanol to Produce Paraxylene. J. Catal. 1981, 67, 159-174. (18) Odedairo, T.; Balasamy, R. J.; Al-Khattaf, S. Toluene Disproportionation and Methylation over Zeolites TNU-9, SSZ-33, ZSM-5, and Mordenite Using Different Reactor Systems. Ind. Eng. Chem. Res. 2011, 50, 3169-3183. (19) Ahn, J. H.; Kolvenbach, R.; Al-Khattaf, S.; Jentys, A.; Lercher, J. A. Methanol Usage in Toluene Methylation with Medium and Large Pore Zeolites. ACS Catal. 2013, 3, 817-825. (20) Van der Mynsbrugge, J.; Visur, M.; Olsbye, U.; Beato, P.; Bjørgen, M.; Van Speybroeck, V.; Svelle, S. Methylation of Benzene by Methanol: Single-Site Kinetics over H-ZSM-5 and H-beta Zeolite Catalysts. J. Catal. 2012, 292, 201-212. (21) Vos, A. M.; Rozanska, X.; Schoonheydt, R. A.; van Santen, R. A.; Hutschka, F.; Hafner, J. A Theoretical Study of the Alkylation Reaction of Toluene with Methanol Catalyzed by Acidic Mordenite. J. Am. Chem. Soc. 2001, 123, 2799-2809. (22) Olsbye, U.; Svelle, S.; Bjørgen, M.; Beato, P.; Janssens, T. V.; Joensen, F.; Bordiga, S.; Lillerud, K. P. Conversion of Methanol to Hydrocarbons: How Zeolite Cavity and Pore Size Controls Product Selectivity. Angew. Chem., Int. Ed. 2012, 51, 5810-5831.
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ACS Catalysis (23) Chowdhury, A. D.; Paioni, A. L.; Houben, K.; Whiting, G. T.; Baldus, M.; Weckhuysen, B. M. Bridging the Gap between the Direct and Hydrocarbon Pool Mechanisms of the Methanol-to-Hydrocarbons Process. Angew. Chem., Int. Ed. 2018, 57, 8095-8099. (24) Liu, Y.; Muller, S.; Berger, D.; Jelic, J.; Reuter, K.; Tonigold, M.; Sanchez-Sanchez, M.; Lercher, J. A. Formation Mechanism of the First Carbon-Carbon Bond and the First Olefin in the Methanol Conversion into Hydrocarbons. Angew. Chem., Int. Ed. 2016, 55, 5723-5726. (25) Huguet, E.; Coq, B.; Durand, R.; Leroi, C.; Cadours, R.; Hulea, V. A Highly Efficient Process for Transforming Methyl Mercaptan into Hydrocarbons and H2S on Solid Acid Catalysts. Appl. Catal. B: Environ. 2013, 134-135, 344-348. (26) Hulea, V.; Huguet, E.; Cammarano, C.; Lacarriere, A.; Durand, R.; Leroi, C.; Cadours, R.; Coq, B. Conversion of Methyl Mercaptan and Methanol to Hydrocarbons over Solid Acid Catalysts - A Comparative Study. Appl. Catal. B: Environ. 2014, 144, 547-553. (27) Cammarano, C.; Huguet, E.; Cadours, R.; Leroi, C.; Coq, B.; Hulea, V. Selective Transformation of Methyl and Ethyl Mercaptans Mixture to Hydrocarbons and H2S on Solid Acid Catalysts. Appl. Catal. B: Environ. 2014, 156-157, 128-133. (28) Dyer, A. An Introduction to Zeolite Molecular Sieves. John Wiley & Sons, Chichester, 1988. (29) Corma, A. Inorganic Solid Acids and Their Use in AcidCatalyzed Hydrocarbon Reactions. Chem. Rev. 1995, 95, 559-614. (30) Ono, Y. Transformation of Lower Alkanes into Aromatic Hydrocarbons over ZSM-5 Zeolites. Catal. Rev. 1992, 34, 179-226. (31) Auerbach, S. M.; Carrado, K. A.; Dutta, P. K. Handbook of Zeolite Science and Technology, Marcel Dekker, New York, 2003. (32) Cejka, J.; Corma, A.; Zones, S. Zeolites and Catalysis: Synthesis, Reactions and Applications, vol 2., Wiley WCH, Weinheim, 2010. (33) Primo, A.; Garcia, H. Zeolites as Catalysts in Oil Refining. Chem. Soc. Rev. 2014, 43, 7548-7561. (34) Mueller, S.; Liu, Y.; Kirchberger, F. M.; Tonigold, M.; SanchezSanchez, M.; Lercher, J. A. Hydrogen Transfer Pathways during Zeolite Catalyzed Methanol Conversion to Hydrocarbons. J. Am. Chem. Soc. 2016, 138, 15994–16003. (35) Chirico, R. D.; Steele, W. V. Thermodynamic Equilibria in Xylene Isomerization. 5. Xylene Isomerization Equilibria from Thermodynamic Studies and Reconciliation of Calculated and Experimental Product Distributions. J. Chem. Eng. Data 1997, 42, 784-790. (36) Lee, C.; Lee, S.; Kim, W.; Ryoo, R. High Utilization of Methanol in Toluene Methylation using MFI Zeolite Nanosponge Catalyst. Catal. Today 2018, 303, 143-149. (37) Forester, T. R.; Howe, R. F. In situ FTIR Studies of Methanol and Dimethyl Ether in ZSM-5. J. Am. Chem. Soc. 1987, 109, 5076– 5082. (38) Bosacek, V. Formation of Surface-Bonded Methoxy Groups in the Sorption of Methanol and Methyl Iodide on Zeolites Studied by Carbon-13 MAS NMR Spectroscopy. J. Phys. Chem. 1993, 97, 10732–10737. (39) Y. Jiang, M. Hunger, W. Wang, On the Reactivity of Surface Methoxy Species in Acidic Zeolites. J. Am. Chem. Soc. 2006, 128, 11679–11692. (40) Wang, W.; Hunger, M. Reactivity of Surface Alkoxy Species on Acidic Zeolite Catalysts. Acc. Chem. Res. 2008, 41, 895–904. (41) Yamazaki, H.; Shima, H.; Imai, H.; Yokoi, T.; Tatsumi, T.; Kondo, J. N. Evidence for a "Carbene-like" Intermediate during the Reaction of Methoxy Species with Light Alkenes on H-ZSM-5. Angew. Chem., Int. Ed. 2011, 50, 1–5. (42) Soscun, H.; Castellano, O.; Hernandez, J. Adsorption of CH3SH in Acidic Zeolites: A Theoretical Study. J. Phys. Chem. B 2004, 108, 5620-5626. (43) Ryzhikov, A.; Hulea, V.; Tichit, D.; Leroi, C.; Anglerot, D.; Coq, B.; Trens, P. Methyl Mercaptan and Carbonyl Sulfide Traces Removal through Adsorption and Catalysis on Zeolites and Layered Double Hydroxides. Appl. Catal. A: Gen. 2011, 397 218–224.
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