Catalytic methane halogenation by bromine over microporous SAPO-34 zeolite material towards methyl bromide, dibromomethane and hydrogen bromide

نویسندگان

چکیده

Background: Bromination-based methane conversion is one of the promising separate ways CH4 valorisation. Both methyl bromide/dibromomethane that are formed can be subsequently transformed into more useful compounds. SAPO-34 could also improve selectivity (S) towards bromomethane during bromination. Methods: To evaluate performance in this reaction process, influence time, temperature (T) and weight hourly space velocity (WHSV) rate was investigated a packed-bed reactor. T range 310–420 ?C, while WHSV 0.22–1.20 h?1. The molar to bromine ratio 5.4:1. GC–MS used for analysis products. Material characterized by XRD, SEM, NH3-TPD, N2 physisorption. Significant findings: In material crystallinity decreased, solid surface area reduced, density Brønsted acid sites reduced compared fresh material. Changes attributed Al2O3 loss or breakage Al–O–P bonds, caused hydrogen bromide ions produced. A presence coke observed on zeolite at higher than 360 ?C. CH2Br2 decomposes, CH3Br released intermediate gas phase. Catalytic yield increase homogeneous not notable, which indicates prevalence elementary radical mechanism. highest S around 90% 310 ?C with 1.20

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ژورنال

عنوان ژورنال: Journal of The Taiwan Institute of Chemical Engineers

سال: 2023

ISSN: ['1876-1070', '1876-1089']

DOI: https://doi.org/10.1016/j.jtice.2022.104645