Effect of carbonization heating rate on CO2 separation of derived carbon membranes

High performance carbon hollow fiber membranes (CHFM) for CO2 separation were prepared by manipulating of carbonization heating rates under a N2 atmosphere. During heat treatment process, carbonization of the polymeric hollow fiber membrane was conducted up to 650 °C and in the range of 1–9 °C/min for heating rate. The gas permeation properties were determined using a single gas permeation apparatus at room temperature. Fine-tuning of the carbonization conditions appears necessary to obtain desired permeation properties. The gas permeance for all examined gases (N2, CH4, CO2) and selectivity of CO2/CH4 and CO2/N2 was decreased and increased, respectively, for the PEI/PVP-based CHFMs prepared at low heating rate. It was found that the heating rate posses significant effect on structure and gas permeation properties of the resultant CHFMs. Experimental results indicated that, carbonization heating rate of 3 °C/min is the best conditions in the preparation of CHFMs derived from polymer blends of PEI/PVP for the CO2/CH4 and CO2/N2 separation