Synthesis and characterization of water-soluble chitosan membrane blended with a mobile carrier for CO2 separation

The present study demonstrates the alteration of chitosan to carboxymethyl chitosan (CMC). Further, this CMC has been blended with a mobile carrier, piperazine (PZ), to prepare a membrane for CO2 separation. Various instruments like nuclear magnetic resonance spectroscopy (NMR), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), thermo gravimetric analysis (TGA) and field emission scanning electron microscopy (FESEM) have been used to characterize the prepared membranes. The moisture holding behavior of the membranes at different relative humidity has been assessed by water retention test. The CO2 separation study was executed at different temperatures (60-120 degrees C) and sweep side water flow rate (0.01-0.09 ml/min). The blend membrane containing 20 wt (wt.) % PZ exhibited optimum CO2 permeance of 89 GPU and CO2/N-2 selectivity of 103 at 80 degrees C and sweep side water flow rate of 0.05 ml/min.