Comparing Solvents for SO2 Absorption by Molecular Dynamics Simulation
Volume Title: 1
1saber moghadam; 2Mahdi Pourafshari Chenar; 3fatemeh moosavi ; 1Mohammad Razmkhah; 4Mohammadhasan Firoozbakht
1Department of Chemical Engineering, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
2Chemical Engineering Department, Faculty of Engineering, Ferdowsi University of Mashhad, Mashhad, Iran
3Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
4Process Engineering Department, Shahid Hasheminejad Gas Processing Company, Iran
One of the 5 major air pollutants is SO2 gas that is released to air, for example, with the exhausted gases from the Claus processes. Shell Cansolv® SO2 Scrubbing System is an amine-based regenerable process that selectively absorbs SO2 from a variety of gases, such as Claus tail gas. Since the solvent formulation of Cansolv process is not available and it has been patented by Shell company, in this paper, based on the related patent, the interactions between N,N',N'-(trimethyl)-N-(2-hydroxyethyl) (A) ethylenediamine and N,N-(dimethyl)-N’,N’-bis-(2-hydroxyethyl) ethylenediamine (B) solvents with SO2 are studied using molecular dynamics simulation. Molecular dynamics simulation shows interactions between solvents and SO2 by use of nitrogen atoms is performed, as a result of which intraction in B solvent is stronger. In addition, Z-density profile (𝜌z) confirms that SO2 gas is completely dispersed in B solvent. The energy absorption value of SO2 gas in A and B solvents are -2.164 kJ.mol-1 and -2.447 kJ.mol-1 respectively. Therefore, stronger interactions, more dispersion and energy absorption performance of B solvent is more efficient in comparison with those of A solvent.