Separation of C3H8 and C2H6 from CH4 in polyurethane–zeolite 4Å and ZSM-5 mixed matrix membranes

• Published in: Separation and purification technology 2015-02, Vol.141, p.394-402
• Main Authors: Tirouni, Iman, Sadeghi, Morteza, Pakizeh, Majid
• Format: Article
• Language: English
• Subjects: Hydrocarbon separation; Mixed matrix membrane; Polyurethane; Zeolite
• ISSN: 1383-5866; 1873-3794
• DOI: 10.1016/j.seppur.2014.12.012

[Display omitted] •PU–Zeolite 4Å and PU–ZSM-5 MMMs evaluated in C2H6/CH4 and C3H8/CH4 separation.•Poly(urethane urea) shows higher hydrocarbon separation performance than PU.•C2H6/CH4 and C3H8/CH4 selectivities decreased in MMMs based on zeolite 4A.•Performance of hydrocarbon separation increased significantly in ZSM-5 based MMMs. In this research, the effects of Zeolite 4Å and ZSM-5 on the separation of C2H6 and C3H8 from CH4 through polyurethane/zeolite mixed matrix membranes (MMM) are evaluated. Physical properties of synthesized polyurethane and polyurethane/zeolite MMM were investigated by FTIR, XRD, TGA and SEM analyses. Results indicate that phase separation of hard and soft segments in polyurethane would be increased by adding butanediamine (BDA) chain extender in polymer due to the generation of more hydrogen bonds between hard segment domains. The obtained SEM micrographs confirm that the Zeolite is distributed in the polymer matrix homogenously. The results of gas permeation represent that permeability and selectivity of Hydrocarbons are increased by increasing the urea groups in the polymer structure. Moreover, the obtained results of gas permeation of polyurethane–zeolite (4Å) membranes indicate an increase in the permeability of Methane, with the reduction in C2H6/CH4 and C3H8/CH4 selectivity by increasing the Zeolite 4Å up to 10wt%. In addition, the results of the gas permeation of polyurethane–zeolite (ZSM-5) MMM indicate a significant increment in permeability and selectivity of all Hydrocarbons. The permeability of Propane and its selectivity over Methane is increased from 64.8 Barrer and 2.6 into 117.2 Barrer and 3.64 in with 20wt% filled PU–ZSM 5 MMM, respectively.