Thermal Degradation Rate of 2-Amino-2-methyl-1-propanol to Cyclic 4,4-Dimethyl-1,3-oxazolidin-2-one: Experiments and Kinetics Modeling

Abstract

Employing experimental kinetics data collected in this study, a power law rate equation for the thermal degradation of 2-amino-2-methyl-1-propanol (AMP) to 4,4-dimethyl-1,3-oxazolidin-2-one (DMOZD) as a function of amine and CO 2 concentration in the solution is introduced. The rate experiments were carried out at 120, 135, and 150 °C. Kinetic data was collected to extract the initial rate equation from aqueous solutions of 1.12, 1.68, 2.24, and 3.36 M, AMP and CO 2 loadings from 0.17 to 0.7, mol CO2 / mol AMP . Since the rate equation is based on the initial reactions in the solution, the output from the kinetic model can be used to estimate the thermal degradation rate of AMP as a whole and DMOZD formation rate at the onset of the reaction, as this cyclic compound can be considered as the primary initial thermal degradation product. The power with respect to AMP and CO 2 concentration in the kinetic model, and activation energy and pre-exponential factor, were calculated and introduced in this work. AMP degradation to the cyclic DMOZD shows close comparability to monoethanolamine (MEA), where the primary initial product is oxazolidin-2-one (OZD), with less tendency in terms of the reaction frequency. In general, AMP thermal degradation to DMOZD displays a lower reaction rate constant compared to MEA. Considering the reaction rate orders of 0.45 (±0.25) and 1.18 (±0.15) for the CO 2 and AMP concentrations in the solution respectively, the DMOZD formation rate displayed more dependency to AMP concentration and less dependency toward CO 2 .

Anomalous Facile Carbamate Formation at High Stripping Temperatures from Carbon Dioxide Reaction with 2-Amino-2-methyl-1-propanol in Aqueous Solution

“…7 The strong hydrogen bonding interaction between nitrogen of AMP and an adjacent water molecule tends to suppress the direct reaction of CO 2 with AMP leading to carbamate formation while facilitating the bicarbonate reaction route. 8,9 According to recent experimental studies, 10,11 AMP may undergo thermal degradation at high stripping temperatures while its main degradation product is found to be 4,4-dimethyl-1,3-oxazolidin-2-one (DMOZD). To explain the DMOZD formation, it has been suggested that AMP could form carbamate (AMPCOO − ) by reacting with CO 2 , 12 similar to the case of MEA.…”

“…From previous experiments, it is now well known that bicarbonate is the predominant product of CO 2 capture by aqueous AMP under absorber conditions. , In addition, recent first-principles studies have revealed that bicarbonate formation via amine-catalyzed hydrolysis can be kinetically more favorable than carbamate formation at relatively low absorber temperatures (<330 K) . The strong hydrogen bonding interaction between nitrogen of AMP and an adjacent water molecule tends to suppress the direct reaction of CO 2 with AMP leading to carbamate formation while facilitating the bicarbonate reaction route. , According to recent experimental studies, , AMP may undergo thermal degradation at high stripping temperatures while its main degradation product is found to be 4,4-dimethyl-1,3-oxazolidin-2-one (DMOZD). To explain the DMOZD formation, it has been suggested that AMP could form carbamate (AMPCOO – ) by reacting with CO 2 , similar to the case of MEA.…”

Thermal Degradation Rate and Kinetic Modeling of CO2-Loaded Amine Solvent Blends of 2-Amino-2-methyl-1-propanol and 1-Amino-2-propanol

“…The initial bulk 2amino-2-methyl-1-propanol (AMP; Acros Organics) and 1amino-2-propanol (A2P; Sigma-Aldrich) solutions were prepared to the target carbon dioxide content. 32 Table 1 shows the composition of each amine in the solutions, along with the total CO 2 loading. The solvent test matrix is composed of seven different combinations of AMP and A2P at CO 2 -rich loading conditions, along with four equal composition blends at four different CO 2 -loadings from lean to rich.…”

“…31 AMP can be prone to degradation at high temperatures, despite its perception as generally being resistant to degradation. 32,33 Previous studies have shown that AMP can form a carbamate (AMPCOO − ) with CO 2 leading to thermal degradation with a similar pathway to that of MEA. 32,34−36 The thermal degradation rate of AMP to its main degradation product, 4,4-dimethyl-1,3-oxazolidin-2-one (DMOZD), was investigated in detail by considering an apparent reaction rate and pseudo-mechanistic approach.…”

An Efficient Solid–Liquid Biphasic Solvent for CO2 Capture: Crystalline Powder Product and Low Heat Duty

“…33,34 In the present work, a novel solid−liquid nonaqueous solution is proposed for CO 2 capture, which will not only feature the advantage of the nonaqueous solution but also that of biphasic solvent and is expected to alleviate the above shortcomings. Combined with the favorable regeneration performance of AMP 35,36 and fast reaction rate of PZ, 21,37 the amine blend of AMP and PZ ensures excellent performance on CO 2 capture. The organic solvent dipropylene glycol dimethyl ether (DME) with a high boiling point and low viscosity is serviced as the solvent and phase splitter, which is considering as an environmentally friendly solvent for nonhazardous in the list of air pollution by the United States and the European Union.…”