Controlled Carbonization Heating Rate for Enhancing CO2 Separation Based on Single Gas Studies

Abstract

Concerns about the impact of greenhouse gas have driven the development of new separation technology to meet CO₂ emission reduction targets. Membrane-based technologies using carbon membranes that are able to separate CO₂ efficiently appears to be a competitive method. This research was focused on the development of carbon membranes derived from polymer blend of polyetherimide and polyethylene glycol to separate CO₂ rendering it suitable to be used in many applications such as landfill gas purification, CO₂ removal from natural gas or flue gas streams. Carbonization process was conducted at temperature of 923 K and 2 h of soaking time. To enhance membrane separation properties, pore structure was tailored by varying the carbonization heating rates to 1, 3, 5, and 7 K / min. The effect of carbonization heating rate on the separation performance was investigated by single gas permeabilities using CO₂ , N₂ , and CH₄ at room temperature. Carbonization heating rate of 1 K / min produced carbon membrane with the most CO₂/ N₂ and CO₂ / CH₄ selectivity of 38 and 64, respectively, with the CO₂ permeability of 211 barrer. Therefore, carbonization needs to be carried out at sufficiently slow heating rates to avoid significant loss of selectivity of the derived carbon membranes.