A research team of National Taiwan University has unveiled "hollow metallic-fiber carbon dioxide absorber" and "catalyst conversion system," both compact devices capable of catching massive amount of carbon at high efficiency and low cost. The new technology can even utilize collected high-density CO2 for conversion into high-value chemicals.

The technology mirrors the new CCU (carbon capture and utilization) trend, part of the emerging cycling economy in recent years, different from past practice in which most of captured CO2 is sealed for storage.

Tung Kuo-lun, professor at the Department of Chemical Engineering NTU who leads the research team, pointed out that the carbon-dioxide absorber is furnished with copper pipes with massive amount of silicon-dioxide particles evenly spread on surface, featuring large unit absorption space (>500 m 2 /m 3), which can absorb massive CO2 in their pores upon flow of cold water.  The trapped CO2 is then detached from the pores using waste heat collected by waste heat system of factory, a method which can slash CO2 treatment cost, since detachment of CO2 accounts for 70% of the cost.

Several devices can be connected for higher processing capacity. A "hollow metallic-fiber carbon dioxide absorber" is only 25 centimeters long and eight centimeters in diameter, containing 200 metallic-fiber absorption pipes, capable of processing 10 kilos of CO2 a day, comparable to the capability of traditional CO2 absorption devices which are 10 times larger.

Alongside the CO2 absorber, the research team has also developed a catalyst conversion device featuring metallic frame with nanometer holes, in which catalyst is sprayed onto ceramic tubes via a novel TPSC (thermal-regulated phase separable catalysis) technology.

The research team managed to overcome the problems of fragility and difficulty for welding in sealing for ceramics simply by utilizing water to lower heat and the resulting steam in manufacturing porous ceramic nanometer film, enlarging reaction space and boosting reaction speed significantly.

The catalyst conversion device utilizes high-purity CO2 and propylene caught by "hollow metallic-fiber carbon dioxide absorber" for production of propylene carbonate via renewed reaction, with conversion rate reaching 75% within 24 hours.

Propylene carbonate (PC) is a high-value chemical material for the production of polymer poly propylene carbonate (PPC), which can be used in producing foam materials, slabstock, and disposable medical/foodstuff packaging materials.

Prof. Tung Kuo-lun (third from the left) and other members of the team and officials of the Ministry of Science and Technology.

(Collaborative media: TechNews, first photo courtesy of TechNews, in which "hollow metallic-fiber carbon dioxide absorber" on the left and "catalyst conversion system" on the right)