Development of CO2 Molecular Gate Membranes for IGCC Process with CO2 Capture

Abstract Carbon dioxide (CO 2 ) capture and storage (CCS) is widely accepted as an important option for mitigating climate change. It is very important to reduce the cost of CO 2 capture to implement CCS. CO 2 capture by membrane is a promising technique because it is energy efficient and simple to operate. One promising means of reducing CO 2 emission is the development of integrated coal gasification combined cycle with CO 2 capture & storage (IGCC-CCS). We are currently developing CO 2 molecular gate membrane, with the goal of producing a new, high-performance separation membrane modules for IGCC-CCS. In the concept of the molecular gate membrane, the pathway for gas molecules is occupied solely by CO 2 , which acts as a gate to block the passage of other gases. Consequently, the amount of H 2 permeating to the permeate side of the membrane is greatly limited and high concentrations of CO 2 can be obtained. As the molecular gate membrane, poly(amidoamine) (PAMAM) dendrimer/polymer hybrid membranes and membrane modules were developed in the METI project, “CO 2  Separation Membrane Module Research and Development Project” (2011FY-2014FY). The cost target was 1,500 JPY/ton-CO 2 . We succeeded in improving the separation performance of such membranes through the modification of poly(vinyl alcohol) (PVA)-based materials, and the target CO 2 separation performance was obtained under high-pressure conditions of 2.4 MPa using laboratory-scale membranes. It was shown that PAMAM dendrimer/polymer hybrid membrane module is suitable for IGCC process with CO 2 capture.