Abstract
Amine scrubbing is usually considered as the most efficient technology for CO<sub>2<sub/> mitigation through postcombustion Carbon Capture and Storage (CCS). However, optimization of the amine structure to improve the solvent properties requires to sample a large number of possible candidates and hence to gather a large amount of experimental data. In this context, the use of QSAR (Quantitative Structure Activity Relationship) statistical modeling is a powerful tool as it performs a mapping of a set of input vectors (i.e. the characteristics or the properties of the molecules under consideration) to a set of output vectors (i.e. their targeted properties). In this work, we used a high throughput screening experimental device to measure CO<sub>2<sub/> solubility data on a set of 46 amine aqueous solutions. Absorption isotherms are represented using a thermodynamic model based on two thermodynamic constants, pKa<sup>*<sup/> and pKc<sup>*<sup/> , accounting for the main chemical reactions occurring in the liquid phase between amine and CO<sub>2<sub/>. Then, we used a statistical approach named Graph Machines at the same time to cluster the molecules and to model the variation of the acidity constant pKa<sup>*<sup/> as a function of the molecular structure. The originality of our approach is the use of graphs to represent molecules in multidimensional spaces and simultaneously construct predictive models of their physicochemical properties based on these graphs. This approach is applied in this paper to predict the thermodynamic properties of a set of 5 new molecules.
Highlights
The control of CO2 emissions to the atmosphere has become a worldwide issue over the last few years as a direct correlation between greenhouse gas emissions and climate change is commonly accepted
Some controversy has arisen in recent literature [1], postcombustion Carbon Capture and Storage (CCS) technology is one of the solution considered on a short-term schedule as it does not require deep modifications of existing power stations [2]
The list of amine molecules screened in this work is reported in Table 1, together with their corresponding SMILES (Simplified Molecular Input Line Entry Specification) which provides a description of the graph structure of the molecule as a character string [41, 42] and their corresponding set for the statistical modeling
Summary
The control of CO2 emissions to the atmosphere has become a worldwide issue over the last few years as a direct correlation between greenhouse gas emissions and climate change is commonly accepted. In a recent work [24], we performed a thermodynamic screening of mono-amines using a High Throughput Screening (HTS) device which was designed to measure CO2 absorption isotherms in aqueous amine solutions This kind of device generates enough experimental data to establish a Quantitative Structure Activity Relationship (QSAR) and to optimize the molecular structure for a specific targeted activity. F. Porcheron et al / Graph Machine Based-QSAR Approach for Modeling Thermodynamic Properties of Amines: methods are applied to estimate the parameters of such functions. Porcheron et al / Graph Machine Based-QSAR Approach for Modeling Thermodynamic Properties of Amines: methods are applied to estimate the parameters of such functions This approach was successfully applied to model boiling point or toxicity of organic molecules [35], anti-HIV activities [36] and more recently to model the adsorption enthalpy of alkanes in zeolites [37]. The list of amine molecules screened in this work is reported in Table 1, together with their corresponding SMILES (Simplified Molecular Input Line Entry Specification) which provides a description of the graph structure of the molecule as a character string [41, 42] and their corresponding set (training, validation, prediction) for the statistical modeling
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
