Design of Co, Cu and Fe–BEA Zeolite Catalysts for Selective Conversion of Lactic Acid into Acrylic Acid

Abstract

Design of the catalytic properties and structure of zeolite materials play a key role in efficient transformation of biomass to sustainable chemicals. In the present study, we have designed theoretical and experimental approach for the production of acrylic acid (AA) from lactic acid (LA) over zeolite catalysts. Various BEA zeolites modified with metals (Co, Cu and Fe) were prepared using ion exchange and sonication methods. In the theoretical studies the metal M-O-M dimers have been found to be stable above oxygen bound with aluminium centers of BEA zeolite. The mechanism of direct LA dehydration over the Co-, Cu-and Fe-BEA zeolites has been proposed. Experimentally, the investigated catalysts trend in following byproduct formation: AA, propionic acid (PA), 2,3-pentanedione (2,3-PD) or acetaldehyde (AC). The best selectivity towards acrylic acid was achieved in the presence of the Co-and Cu-BEA catalysts prepared by the sonication method.

On the catalytic vapor-phase dehydration of lactic acid to acrylic acid: a systematic review

“…For the first time, this contribution communicated an effective transition metal-based catalyst system for the dehydration of LA to AA. 105 The two preparative methods led to a distinct difference in the reaction outcomes. Ion exchange favors LA decarbonylation to AD or LA condensation to 2,3-PD, whereas sonication facilitates LA dehydration to AA or PA.…”

“…From the comparative catalytic data between the sodium form and modified zeolite systems in Table 6, most of the modified zeolite systems are able to bring about an enhancement in the AA yield at the initial stage to a different extent by at least 15% with the alkali metal-modified systems, 32,[97][98][99][100][101][102] by at most 10% with the alkaline-earth metalmodified systems, 94 by at most 21% with the rare-earth metalmodified systems, 92 and by at least 106% with the transition metal (Cu and Co)-modified systems. 105 Although the catalytic stability is more or less improved with the modified zeolite systems compared to the sodium form zeolite systems, the obtained results are unsatisfactory. It is consistently admitted from all the available reports that the modified zeolites possess a decreased acid strength (or acidity).…”

Stable catalysis of neutral silica-supported potassium lactate for vapour-phase dehydration of lactic acid to acrylic acid – critical role of the support

“…Catalytic vapour-phase dehydration of LA to AA has been developed into a category of so-called solid acid- or solid acid–base-catalyzed reactions. 21,22,26–30,34–60 Stronger solid acids such as NaY (Si/Al = 1.3–4.5 molar ratio), ZSM-5 (Si/Al = 14–25 molar ratio) and zeolite beta (Si/Al = 20 molar ratio) were utilized as components of catalyst systems. 26,28,34–37,42,45–48,52,53,55,59 Moreover, acid-base bifunctional catalyst systems arose, which have both acid and base sites.…”

“…21,22,[26][27][28][29][30] Stronger solid acids such as NaY (Si/Al = 1.3-4.5 molar ratio), ZSM-5 (Si/Al = 14-25 molar ratio) and zeolite beta (Si/Al = 20 molar ratio) were utilized as components of catalyst systems. 26,28,[34][35][36][37]42,[45][46][47][48]52,53,55,59 Moreover, acid-base bifunctional catalyst systems arose, which have both acid and base sites. 27,29,30,[35][36][37][38][41][42][43][44][46][47][48][50][51][52][53][54]56,57 As a result of the presence of stronger solid acid sites which easily induce LA decarbonylation and LA polymerization (which eases coke formation), catalytic stability for the production of AA declined and catalysts deactivated faster than expected, although initial catalytic activity and selectivity were prominent.…”

Selective Mesitylene Oxidative Coupling Reaction by Metastructured Electrocatalyst Comprised of Carbonaceous Scaffold Coated with Pd Derived from Zeolitic Imidazole Framework

“…However, due to their insulating nature, they cannot be used as electrode material [9]. It would be ideal to develop an electrode material by exploiting the conducting nature of carbon and ordered porosity similar to zeolites [10]. In this regard, carbon material derived from the Zeolitic Imidazolate Frameworks (ZIFs) [11] may be a good choice since it has zeolite-like ordered structure along with high conductivity [12], and it may enhance the electrocatalytic efficiency [13] and size-/shape-selectivity for the desired products [14,15].…”