Molecular Dynamics Simulation of Gas Transport in Polyisoprene Matrix

Abstract:

Molecular Dynamics (MD) simulation was employed to study the diffusivity of biogas in a PI matrix with the aim to verify simulations as a useful tool to predict PI membrane properties for biogas treatment. The simulation model of PI numerical was reliable and accurate in predicting both the material properties and the diffusivity of gases in PI matrix. The diffusion coefficients (D) of the major components in biogas, namely CH₄, CO₂, H₂O, O₂, and N₂, were computed by simulating trajectories of each gas in PI matrix at 300 K. The simulations gave D_CO2 that was 6 times larger than D_CH4, and this agrees well with permeabilities reported in the literature. This suggests that PI membranes could be used to treat biogas by separating CO₂ and CH₄. However, the diffusivities of N₂, H₂O, and CH₄ are closely similar, so PI membranes are not capable of separating these. The potential application of PI membrane to CO₂/CH₄ separation seems worth further exploration.

• Periodical: Advanced Materials Research (Volume 844)
• Pages: 209-213
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.844.209
• Online since: November 2013
• Authors: Natthida Rakkapao*
• Keywords: Biogas Treatment, Diffusion, Gas, MD Simulation, Polyisoprene

References

[1] S. Rasi, A. Veijanen, J. Rintala, Trace compounds of biogas from different biogas production plants, Energy. 32 (2007) 1375-1380.

DOI: 10.1016/j.energy.2006.10.018

[2] L. Petychakis, G. Floudas, G. Fleischer, Chain dynamics of polyisoprene confined in porous media, A dielectric spectroscopy study, EPL (Europhysics Letters). 40 (1997) 685-690.

DOI: 10.1209/epl/i1997-00523-2

[3] B. Valenti, A. Turturro, S. Losio, L. Falqui, G. Costa, B. Cavazza, M. Castellano, Styrene-diene block copolymers as embedding matrices for polymer-dispersed liquid crystal films, Polymer. 42 (2001) 2427-2438.

DOI: 10.1016/s0032-3861(00)00616-9

[4] S. C. Ng, K. K. Chee, Solubility parameters of copolymers as determined by turbidimetry, European Polymer Journal. 33 (1997) 749-752.

DOI: 10.1016/s0014-3057(96)00155-3

[5] P. Piya-areetham, P. Prasassarakich, G. L. Rempel, Organic solvent-free hydrogenation of natural rubber latex and synthetic polyisoprene emulsion catalyzed by water-soluble rhodium complexes, Journal of Molecular Catalysis A: Chemical. 372 (2013).

DOI: 10.1016/j.molcata.2013.02.025

[6] N. H. H. Abu Bakar, J. Ismail, M. Abu Bakar, Synthesis and characterization of silver nanoparticles in natural rubber, Materials Chemistry and Physics. 104 (2007) 276-283.

DOI: 10.1016/j.matchemphys.2007.03.015

[7] F. Alvarez, A. Arbe, J. Colmenero, R. Zorn, D. Richter, Partial structure factors of a simulated polymer melt, Computational Materials Science. 25 (2002) 596-605.

DOI: 10.1016/s0927-0256(02)00340-3

[8] T. Dobre, O. C. Pârvulescu, J. Sanchez-Marcano, A. Stoica, M. Stroescu, G. Iavorschi, Characterization of gas permeation through stretched polyisoprene membranes, Separation and Purification Technology. 82 (2011) 202-209.

DOI: 10.1016/j.seppur.2011.09.019