Effects of Microwave Irradiation on Activation Energy and Reaction Rate of Synthesis of Dodecylmethyldihydroxyl Ammonium Bromide

Abstract

The reaction kinetics of the synthesis of quaternary ammonium salt under two sets of different reaction conditions, including microwave irradiation condition and conventional heating condition, were studied. In order to make sure that the microwave would not be interrupted, the reaction temperature was maintained at the boiling point of reaction solvents. The results showed that the reaction was a first-order reaction under both set of conditions and microwave irradiation changed the value of the activation energy of the reaction, indicating a change in the reaction mechanism. The activation energy was 41.44 kJ/mol under microwave irradiation condition, and 61.21 kJ/mol under conventional condition.

Advantages and Limitations of Microwave Reactors: From Chemical Synthesis to the Catalytic Valorization of Biobased Chemicals

“…Most investigations in the literature − could be described either as influenced by the thermal effect or by a combination of thermal and nonthermal effects, if existent. However, there is still much controversy in the literature, which culminated into several heated discussions. − Most importantly, temperature measurement, homogeneity of the reaction components, and reactor design are critical experimental variables for a true comparison of microwave-assisted reaction with conventional heating.…”

Applying a unified process kinetic equation to advanced materials process analysis: Characterization of the kinetics of isothermal microwave‐assisted chemical syntheses

“…Proposed rationale, analysis and conclusions on kinetics-enhancements in IMACS are fully supported by relevant process-kinetics data obtained from various types of microwave-assisted syntheses: (1) inorganic syntheses-copper oxide reduction, 18,44 carbon oxidation, 45 (2) organic syntheses-fullerol formation, 46 quaternary ammonium salt synthesis, 47 polyamid acid synthesis, 48 and (3) polymeric syntheses-carvone isomerization, 49 acrylic acid crosslinking/polymerization, 50 epoxy resin curing, 51 and solution imidization. 52…”

“…In the field of microwave‐augmented chemistry, rate‐enhancements of isothermal chemical (inorganic, organic, or polymeric) syntheses conducted under resonant microwave (RM) irradiation versus their counterpart processes activated by conventional (field‐free) heating have been widely recognized. Typical kinetic data obtained from syntheses under both conventional field‐free heating and RMF heating conditions are tabulated and compared in Table 1 18,44–52 . Evidently, kinetics‐enhancements of chemical reactions conducted under…”

“…Typical kinetic data obtained from syntheses under both conventional field-free heating and RMF heating conditions are tabulated and compared in Table 1. 18,[44][45][46][47][48][49][50][51][52] Evidently, kinetics-enhancements of chemical reactions conducted under RMF heating were attributed to a significant reduction in activation enthalpy, AE, of each individual process. Nonetheless, the pre-exponential frequency coefficients, R K RM , of all syntheses conducted under RMF heating were also reported to be, at various extents, lower than their counterparts, R K o , the pre-exponential frequency coefficients obtained under conventional field-free heating.…”

A Review of Microwave-Assisted Reactions for Biodiesel Production

“…Moreover, Mao et al [ 63 ] reported that the synthesis of quaternary ammonium salt with the microwave-assisted process was far more effective due to its lower activation energy (41.44 kcal/mol) in comparison to the conventional thermal heating method (61.21 kcal/mol). This phenomenon was explained as the result of the non-thermal microwave effect.…”