Open AccessPolyethyleneimine Supported Mesoporous Silica for CO2 Capture: Adsorption Kinetics and Degradation Problems
Author(s) -
Đặng Viết Quang,
Tara Nelson,
Mohammad R.M. Abu-Zahra
Publication year - 2015
Publication title -
international journal of thermal and environmental engineering
Language(s) - English
Resource type - Journals
ISSN - 1923-7316
DOI - 10.5383/ijtee.11.02.001
Subject(s) - sorbent , adsorption , kinetics , mesoporous material , diffusion , degradation (telecommunications) , chemical engineering , mesoporous silica , chemistry , materials science , catalysis , organic chemistry , thermodynamics , computer science , engineering , telecommunications , physics , quantum mechanics
Polyethyleneimine supported mesoporous silica (PEI-MPS) has widely been investigated as solid sorbents for CO2 adsorption in laboratory. However, the adsorption kinetics of CO2 on this sorbent is still a disputed problem and the sorbent degradation could be a cause that hinders the sorbent from industrial application. In this study, the PEI-MPS sorbent was prepared by impregnating PEI onto mesoporous silica and then the adsorption kinetics was investigated using the pseudofirst order model, pseudo-second order model and intraparticle diffusion model. Results indicated that the CO2 adsorption kinetics on the sorbent occurred in a 2 stage process. In early stage, it is well fitted by the pseudo-first order model, but in later stage, it is well fitted by the intraparticle diffusion model. The pseudo second-order model proved to be the most suitable one to describe the adsorption of CO2 on the sorbent for the whole adsorption period with less than 5% absolute deviation. The sorbent with a CO2 adsorption capacity of 144.9 mg/g was calculated based on the fitting of the pseudo- second order model. The major degradation issues and their potential effects on the CO2 capture process were also discussed. The degradation significantly impacts on the performance and efficiency of CO2 capture process. The chemical degradation, however, can be considerably minimized by humidification.