Карбонилирование диметилового эфира с использованием катализаторов на основе фосфорно-вольфрамовой кислоты и ее солей

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В обзоре проведен анализ реакции карбонилирования диметилового эфира (ДМЭ) с использованием катализаторов на основе фосфорно-вольфрамовой кислоты и ее солей. Методом 13C MAS ЯМР проанализированы и сравнены механизм и кинетика карбонилирования ДМЭ на образцах H3PW12O40, Cs2HPW12O40, Rh/Cs2HPW12O40, Pt/Cs2HPW12O40, Ag/Cs2HPW12O40. В гетерогенном карбонилировании ДМЭ рассмотрены катализаторы, представляющие собой цезиевые соли фосфорно-вольфрамовой кислоты, а также ее родиевые и иридиевые соли, нанесенные на алюмосиликатные и силикатные носители.

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Sobre autores

Вера Остроумова

Институт нефтехимического синтеза им. А. В. Топчиева РАН

Autor responsável pela correspondência
Email: ostroumova@ips.ac.ru
ORCID ID: 0000-0003-2870-6534

к. х. н.

Rússia, Москва, 119991

Антон Максимов

Институт нефтехимического синтеза им. А. В. Топчиева РАН; Московский государственный университет имени М. В. Ломоносова

Email: ostroumova@ips.ac.ru
ORCID ID: 0000-0001-9297-4950
Rússia, Москва, 119991; Москва, 119991

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2. Fig. 1. Keggin structure of H3PW12O40 (three types of external oxygen atoms: Ob, Oc, Od in the molecule structure, Oa - central oxygen atom) (according to [28]).

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3. Fig. 2. Preparation of methyl acetate from dimethyl ether by the Koch mechanism (according to [6]).

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4. Fig. 3. CP/MAS NMR 13C spectra of the complexes formed upon adsorption of DME on H3PW12O40, Cs2HPW12O40, Rh/Cs2HPW12O40 at: a) 293 K, 30 min; b) 373 K, 30 min; c) 423 K, 30 min); and on Ag/Cs2HPW12O40 and Pt/Cs2HPW12O40 at: d) 293 K; e) 423 K; f) 473 K). The rotational speed was 5.0 kHz. The asterisks (*) denote the lateral rotation bands (according to [37, 38]).

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5. Fig. 4. CP/MAS 13C NMR spectra of particles formed by 13CO at 293-423 K on the surface of: a) Rh/Cs2HPW12O40; b) Pt/Cs2HPW12O40, c) Ag/Cs2HPW12O40. The magnetic field rotation rate was 8.0 kHz; asterisks (*) denote lateral rotation bands (according to [38]).

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6. Fig. 5. CP/MAS NMR 13C spectra of the products obtained from the interaction of DME-13C and 13CO on Rh/Cs2HPW12O40: (a) at room temperature; (b) at 400 K for 30 min, (c) at 423 K for 30 min, (d) at 423 K for 90 min; and on Ag/Cs2HPW12O40 and Pt/Cs2HPW12O40 at (e) 293 K, (f) 423 K for 60 min, (g) 473 K for 30 min, (h) 473 K for 2 h. The asterisks denote the lateral rotation bands (according to [37, 38]).

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7. Fig. 6. CP/MAS 13C NMR spectra of the carbonylation products of DME-13C 13CO on Cs2HPW12O40: a) at room temperature; b) at 423 K for 30 min, c) at 473 K for 60 min.

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8. Fig. 7. Stack plot of 1H MAS NMR spectra: a) at 453 K of DME adsorbed on H3PW12O40 and reacting with CO. The initial spectrum was recorded after 5 min after reaching the temperature of 453 K, the final spectrum was recorded after 400 min of reaction; b) at 449 K DME adsorbed on Rh/Cs2HPW12O40 and reacting with CO. The initial spectrum was recorded 5 min after reaching 449 K and the final spectrum was recorded after 180 min of reaction; c) at 482 K DME adsorbed on Ag/Cs2HPW12O40 and reacting with CO. The initial spectrum was recorded 2 min after reaching a temperature of 482 K, and the final spectrum was recorded after 80 min of reaction (according to [38, 66]).

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9. Fig. 8. Arrhenius curves for the initial rate, W0DME, of DME carbonylation on: (○) - Rh/Cs2HPW12O40; (□) - Pt/Cs2HPW12O40; (∇) - Ag/Cs2HPW12O40 (from [66]).

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10. Fig. 9. Diffractograms of samples χ wt% of GPC/SBA-15 (according to [80]).

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11. Fig. 10. TEM samples: a) 25 wt% GPC/SBA-15 and b) 75 wt% GPC/SBA-15 (according to [80]).

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12. Fig. 11. Dependence of: a) methyl acetate yield on flow time; b) selectivity for methyl acetate on different samples χ wt% GPC/SBA-15. Reaction conditions: catalyst mass = 1 g, DME/CO ratio (1 : 49), temperature 473 K, pressure 1.5 MPa, total flow rate = 30 ml/min, flow time = 1.5 h (according to [80]).

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13. Fig. 12. Selectivity for methyl acetate and by-products (methanol: MeOH, methyl formate MF, acetic acid AcOH) on χ wt% GPC/SBA-15 samples. Reaction conditions: catalyst mass = 1 g, DME/CO ratio (1 : 49), temperature 473 K, pressure 1.5 MPa, total flow rate = 30 ml/min, flow time = 1.5 h (according to [80]).

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14. Fig. 13. Conversion and product composition profiles when using: a) 58 wt% RhPW12O40/SiO2; b) 58 wt% IrPW12O40/SiO2. Flow conditions: 3 : 1 (molar) CO : DME, WHSV = 0.15 h-1; carrier: Aldrich grade 12, 28- 200 mesh; operating conditions: 498 K, 10 MPa (according to [6]).

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15. Fig. 14. Methyl acetate selectivity profiles using: a) 58 wt% RhPW12O40/SiO2; b) 58 wt% IrPW12O40/SiO2. Flow conditions: 3 : 1 (molar) CO : DME, WHSV = 0.15 h-1; carrier: Aldrich grade 12, 28- 200 mesh; operating conditions: 498 K, 10 MPa (according to [6]).

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