Catalytic Performance of Lanthanum Vanadate Catalysts in Ammoxidation of 2-Methylpyrazine

Abstract

Abstract:The influence of reaction conditions on the catalytic performance of lanthanum vanadate (La 0.1 V 0.9 O x ) catalyst in the ammoxidation of 2-methylpyrazine (MP) to 2-cyanopyarazine (CP) has been investigated. This novel catalytic material exhibited remarkably good performance with very high space-time-yields (STY) of CP. The reaction parameters such as the effect of temperature, gas hourly space velocity (GHSV) and all other reaction variables (e.g., NH 3 , air, and MP feed rates) on the catalytic performance were explored and optimized. For example, an increase in MP feed rate from 2 to >16 mmol/h led to decreased conversion of MP but increased the STY of CP significantly. Optimal performance was achieved when the reaction temperature was 420˝C and the molar ratio of 2-MP, ammonia, air, H 2 O and N 2 in the feed gas was set to 1:7:26:13:22. Under these optimal reaction conditions, the catalyst showed a MP conversion of~100%, CP selectivity of 86%, and STY of >500 g CP /(kg cat¨h ). On the other hand, the formation of pyrazine (Py) as a by-product was found to be high when the NH 3 :MP ratio was lower at increased contact time. This suggests possible differences in the reaction mechanism pathways with respect to feed composition over La 0.1 V 0.9 O x catalysts.

Process Development and DFT‐Assisted Mechanism of the Vapour Phase Ammoxidation of 2,6‐Dichlorotoluene to 2,6‐Dichlorobenzonitrile over the V2O5/γ‐Al2O3 Catalyst

“…found that the V 2 O 5 phase is present in major proportion than AlVO 4 . Kalevaru et al . also confirm V 2 O 5 phase significantly more active for the ammoxidation reactions than AlVO 4 phase.…”

“…Usually unsupported vanadium phosphates (VPO) and V–Cr–O have been used as catalysts for the ammoxidation 2,6‐DCLT . In the last two decades, supported vanadia catalysts have received much attention for selective oxidation and ammoxidation of hydrocarbons because the use of supported catalyst has more advantages over an unsupported one. Supported Vanadia‐based systems (especially vanadia–Alumina) have a well‐established position among industrial catalysts.…”

General and Prospective Views on Oxidation Reactions in Heterogeneous Catalysis

“…Moreover, it was also reported that both W-V-O and W-V-Nb-O catalysts are active for methanol oxidative transformation to formaldehyde and dimethyl ether (DME). Catalytic performance of lanthanum vanadate (La 0.1 V 0.9 O x ) catalyst in the ammoxidation of 2-methylpyrazine (MP) to 2-cyanopyarazine (CP) has also been investigated [15]. The recent developments in the field of catalytic partial oxidation of ethane to oxygenated products have been comprehensively reviewed [16].…”

Catalytic Conversion of Biomass

“…In this regard, Song et al contributed to develop an efficient dehydration of fructose to HMF using heteropolyacid salts [1]. Along similar lines, two additional contributions for the Special Issue from Li et al [2] and Fachri et al [3] disclosed the catalytic aqueous conversion of glucose and inulin into HMF using Lewis acid and metal salts catalysts, respectively, providing also interesting modelling insights into the proposed chemistries.…”