Open AccessImproved CO2 Sorption Performance of Calcium Oxide (CaO) Sorbent with Nickel Oxide Additive
Author(s) -
Vitiyaa Selva Kumar,
Zhi Hua Lee,
Jia Huey Sim,
Ser Chyen Law,
Abdul Rahman Mohamed
Publication year - 2019
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/268/1/012026
Subject(s) - sorption , carbonation , sorbent , non blocking i/o , nickel oxide , calcium oxide , oxide , nickel , materials science , inorganic chemistry , chemical engineering , chemistry , nuclear chemistry , adsorption , metallurgy , catalysis , organic chemistry , composite material , engineering
Currently, carbon capture and storage (CCS) technology appeared to be the most viable method to reduce carbon dioxide (CO 2 ) emission from its existing sources. This paper reports the improved performance of calcium oxide (CaO)-based sorbents with the addition of nickel oxide (NiO) as an additive (denoted as CaO:NiO) in CO 2 sorption process (CaO carbonation reaction). Pure CaO was used as benchmarked sorbent in this study. The samples were synthesized using the sol-gel method and CaO:NiO were evaluated for their performance in CaO carbonation at different sorption temperatures, from its CO 2 sorption capacity, CO 2 sorption rate, and kinetic performance. CaO:NiO has demonstrated an excellent CO 2 sorption capacity of 0.79 mmol CO 2 /mmol CaO, meanwhile pure CaO exhibited lower CO 2 sorption capacity of 0.61 mmol CO 2 /mmol CaO at 600 °C. During the chemical reaction controlled stage, the CO 2 sorption rate of CaO:NiO was 0.78 mmol CO 2 /mmol CaO.min at 600 °C compared to pure CaO with sorption rate of 0.18 mmol CO 2 /mmol CaO.min. This study indicates that the addition of nickel oxide has successfully improved the CO 2 sorption rate and capacity of CaO for CaO:NiO. Based on the kinetic study, it has been observed that the diffusion controlled stage has a greater resistance towards the CO 2 sorption process (carbonation reaction) compared to rapid chemical reaction controlled stage. Experimental carbonation data for CaO:NiO fitted very well to the shrinking core model (SCM) with high correlation coefficient (R 2 >0.936). The specific rate constants of rapid chemical reaction and diffusion-limited stages are directly proportional to the carbonation temperature. The activation energy required for CaO:NiO sorbent during the chemical reaction control stage was 31.81 kJ/mol.