Conversion of Methyl Mercaptan to Hydrocarbons over H-ZSM-5 Zeolite: DFT/BOMD Study

Reina, Miguel; Martı́nez, Ana; Cammarano, Claudia; Leroi, Catherine; Hulea, Vasile; Mineva, Tzonka

doi:10.1021/acsomega.7b00756

Cited by 11 publications

(14 citation statements)

References 65 publications

(130 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In a recent theoretical study, we compared methanol and methyl mercaptan as methylating agents through a stepwise mechanism. 10 Accordingly, the pathway of the methylation of toluene by CH 3 SH (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.…”

mentioning

confidence: 97%

“…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. However, the aim was to generate C−S bonds, mostly for preparing biologically and pharmaceutically active molecules.…”

mentioning

confidence: 99%

“…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 . Note that reactions between the aromatic and sulfur compounds were widely investigated during the last decades.…”

mentioning

confidence: 99%

“…In a recent theoretical study, we compared methanol and methyl mercaptan as methylating agents through a stepwise mechanism . Accordingly, the pathway of the methylation of toluene by CH 3 SH (represented in Scheme b) is similar to that of methanol (Scheme a).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Toluene Methylation by Methyl Mercaptan and Methanol over Zeolites—A Comparative Study

et al. 2018

Self Cite

View full text Add to dashboard Cite

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 CH 3 SH 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 CH 3 SH was compared with the well-known reaction between toluene and CH 3 OH. Significant similarities exist, notably the ability of both CH 3 SH and CH 3 OH 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 CH 3 OH was reached at 350 °C, while that of 67.3% for CH 3 SH 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 (CH 3 OH) and 26.4 kcal/mol (CH 3 SH)). The high performance in alkylation proved by CH 3 SH was attributed to its lower consumption in the side reactions (i.e., the formation of light hydrocarbons).

show abstract

mentioning

confidence: 97%

mentioning

confidence: 99%

mentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Toluene Methylation by Methyl Mercaptan and Methanol over Zeolites—A Comparative Study

et al. 2018

Self Cite

View full text Add to dashboard Cite

show abstract

“…The following three thermocatalytic methods are the most promising for gas processing plants (GPP). The first of them is based on the reaction of decomposition of mercaptans to hydrogen sulfide and hydrogen on solid catalysts, which is carried out at a pressure and temperature (200-350 °C) of the adsorbent regeneration [6][7][8][9][10][11][12]. The practical implementation of this method at GPP is facilitated by the availability of energy at the plant for further purification of regeneration gas from hydrogen sulfide formed during the decomposition of mercaptans, and its utilization by the Claus process.…”

Section: Methods For Adsorption Purification Of Associated Oil Gases Fmentioning

confidence: 99%

Method for Adsorption Purification of Associated Oil Gases From Mercaptans

Ismagilov¹,

Ахметов²,

M.K.,³

et al. 2020

OF THE ACADEMY OF SCIENCES OF THE REPUBLIC OF KAZAKHSTAN JSC «D

View full text Add to dashboard Cite

The paper examines methods of utilization of zeolite regeneration gases to assess the possibility of using them in an industrial adsorption unit for drying and purifying gases from hydrogen sulfide and mercaptans. The most promising is the method of decomposition of mercaptans to hydrogen sulfide and hydrogen on solid catalysts, which is carried out at a pressure and temperature of 200-350 °C, as well as the method of direct gas-phase catalytic oxidation of mercaptans with atmospheric oxygen. We carried out experiments on the purification of zeolite regeneration gases of the Orenburg GPP by oxidation with atmospheric oxygen using an iron oxide catalyst at a temperature of 180-250 °C. They showed that the gas purified from mercaptans contained elemental sulfur and disulfides as the main oxidation products, and 0.2% vol. of sulfur dioxide was present as a by-product. The method of purification from mercaptans and heavy hydrocarbon gases regeneration of composite adsorbent by thermocatalytic oxidation is also proposed. To reduce the yield of undesirable sulfur dioxide in the regeneration gas purified from mercaptans, it is proposed to divide the regeneration gas stream into two streams, while the larger part, comprising about 80-90% vol., is sent to oxidation on a zinc-iron catalyst at 200 °C, the second stream is mixed with oxidation products in a volume ratio in terms of mercaptans and sulfur dioxide equal to 1.5-2.2÷1, respectively, then the resulting mixture is passed at 160-200 °C through a titanium oxide catalyst with a gas volumetric velocity of 4000-6000 h-1. The proposed scheme for gas purification from mercaptans and heavy hydrocarbons on a composite adsorbent with oxidative regeneration makes it possible to carry out the subsequent process of amine purification of gas from hydrogen sulfide without the complications associated with foaming of the working solution. Furthermore, it becomes possible to transport gas purified from mercaptans and hydrogen sulfide through the pipeline without precipitation of condensate.

show abstract