Selective separation of CO2 using novel mixed matrix membranes based on Pebax and liquid-like nanoparticle organic hybrid materials

Abstract Pebax1657 is known as a promising polymeric membrane material for CO 2 separation. In order to further improve its gas separation performance, different polymers containing ethylene oxide (EO) groups are incorporated into the Pebax1657 matrix to form mixed matrix membranes (MMMs). Liquid-like nanoparticle organic hybrid materials (NOHM-I-HPE, “I” stands for “ionic bond” and “HPE” refers to polyetheramine (“PE”) with a high (“H”) ether group content), which are made of polyetheramine chains tethered onto functionalized silica nanoparticles, have shown high solubility of CO 2 . In this study, the homogenous NOHM-I-HPE/Pebax1657 MMMs with different NOHM-I-HPE loadings are prepared and investigated. The results indicate that the addition of NOHM-I-HPE leads to a decrease in glass transition temperature of Pebax1657 and an increase in EO content of the MMMs. Influences of NOHM-I-HPE content on CO 2 , N 2 and CH 4 permeations are investigated at 23 °C and 1 bar. For the NOHM-I-HPE loading ranging from 0 to 60 wt%, solubility coefficients of the MMMs for CO 2 greatly increase from 1.16 to 3.84 cm 3 (STP)/(cm 3 ·bar), while those for CH 4 and N 2 only increase from 0.078 to 0.094 cm 3 (STP)/(cm 3 ·bar) and from 0.013 to 0.026 cm 3 (STP)/(cm 3 ·bar), respectively. Although the CO 2 /N 2 selectivity slightly decreases with an increase in the NOHM-I-HPE loading, the CO 2 /CH 4 selectivity is improved in the newly developed NOHM-I-HPE/Pebax1657 MMMs. These results indicate that the NOHM-I-HPE/Pebax1657 MMMs are very promising candidates for selective CO 2 separation for various energy related applications.