VOLUME 68 : 2020

Global warming is being faced by humanity since the dawn of the third millennium. On the rise of emerging solutions to mitigate this phenomenon, adsorption is known for its effective carbon capture mechanism. This study determined the influence of pyrolysis conditions on the adsorption capacity of rice straw derived biochar adsorbents for potential application to carbon dioxide capture. Two pyrolysis conditions were varied: pyrolysis temperature and pyrolysis residence time. Under constant residence time of 2 h, the pyrolysis temperature was varied to 300°C, 400°C, 500°C, and 600°C. Meanwhile, under constant pyrolysis temperature of 600°C, the residence time was varied to 1 h, 2 h, 3 h, and 4 h. The adsorbents were characterized using scanning electron microscope (SEM) and thermogravimetric analyzer (TGA). The SEM images of the rice straw samples showed successful development of pore sites and flaky layers after pyrolysis. Results showed higher CO2 adsorption capacity for samples pyrolyzed at higher temperature. However, increasing the residence time at the highest temperature during pyrolysis did not result to higher adsorption capacity. The highest adsorption capacity of 2.81 wt% was observed for the sample pyrolyzed at 600°C for 1 h. The pyrolysis temperature compared to the residence time is more influential on the adsorption capacity of the rice straw-derived biochar.