Hierarchical ZSM-5 Zeolite Synthesized by an Ultrasound-Assisted Method as a Long-Life Catalyst for Dehydration of Glycerol to Acrolein

Abstract

This paper presents a facile and economical route to synthesizing hierarchical porous ZSM-5 zeolite (HP-ZSM-5) by an ultrasound-assisted method as a long-life catalyst for the glycerol dehydration reaction, which is an important reaction for the sustainable production of acrolein from biobased glycerol. The systematic characterizations indicate that the HP-ZSM-5 catalyst possesses large intracrystal mesopores and abundant accessible acid sites. The ultrasonic treatment and violent stirring play a critical role in the synthesis process. Compared with commercial ZSM-5 zeolite (C-ZSM-5), the turnover-frequency value at time zero of the HP-ZSM-5 catalyst increased nearly 1 times, and the lifetime of the HP-ZSM-5 catalyst was prolonged 9 times. The HP-ZSM-5 catalyst exhibits a slower coking rate with higher coke tolerance, the coke preferentially form inside the intracrystal mesopores, and the ratio of hardly removed graphitic carbon is lower than that of C-ZSM-5. The HP-ZSM-5 catalyst exhibits prominent stability of nearly 50 h and a high acrolein selectivity of 82%.

Facile Synthesis of a Novel Hierarchical ZSM‐5 Zeolite: A Stable Acid Catalyst for Dehydrating Glycerol to Acrolein

“…found that enhancing the amount of mesopores surface area in ZSM‐5 had a major impact on retarding deactivation in the methanol to olefin conversion . Recently, we developed an economical synthesis approach for hierarchical porous ZSM‐5 zeolites by using an ultrasound‐assisted procedure …”

Metal–Organic Framework Mediated Synthesis of Small‐Sized γ‐Alumina as a Highly Active Catalyst for the Dehydration of Glycerol to Acrolein

“…[1] Glycerol is one of the top-12p latform chemicals, as it can be converted into value-added chemicals. [8] Suprune tal. [3] Ac onsiderable number of studies on the gas-phase dehydration of glycerol over solid acid catalysts have been undertaken.…”

“…[3] Ac onsiderable number of studies on the gas-phase dehydration of glycerol over solid acid catalysts have been undertaken. [8] Suprune tal. g-Al 2 O 3 is aw ell-known acidic metal oxide, and Kostestkyy et al [5] suggested that g-Al 2 O 3 was more efficient in catalyzingd ehydration reactions than either titania or zirconia, as determined by theory and experiment.…”

“…g-Al 2 O 3 is aw ell-known acidic metal oxide, and Kostestkyy et al [5] suggested that g-Al 2 O 3 was more efficient in catalyzingd ehydration reactions than either titania or zirconia, as determined by theory and experiment. [8] Suprune tal. [6] The main challenge in the design of alumina catalysts for the glycerold ehydration reaction lies in overcoming the low selectivity to acrolein and obtaining highers tability for industrial application.…”

“…The results are consistentw ith evolution of catalytic stability. [8,9] M-Al 2 O 3 has as maller size than C-Al 2 O 3 and N-Al 2 O 3 and this favors rapid desorption of the products andi nhibits furtherr eaction of the products over the acid sites. Lakiss et al [37] suggested that the superiors tabilityo fs mall-sized zeolitesw as clearlyr elated to much shorter diffusion path lengths, which severely limited the number of consecutive transformationsl eadingt o coke.…”