The objective of
the current research is to investigate the addition
of a solid proton donor catalyst such as HZSM-5 and Ce(SO4)2/ZrO2 to the amine solvent regeneration process
at the operation temperature
of 85 °C. The HZSM-5 zeolite with Si/Al ratios of 5 to 20 was
synthesized by hydrothermal method. The solid superacid catalyst,
Ce(SO4)2/ZrO2, was prepared by simply
doping ZrO2 with Ce and modifying with sulfate simultaneously.
Various techniques such as X-ray diffraction, energy-dispersive X-ray
spectrometry, Brunauer―Emmett―Teller, NH3-temperature-programmed desorption, and pyridine Fourier transform
infrared spectroscopy were used to characterize the solid acid catalysts.
The performance of the catalysts was evaluated in terms of their CO2 desorption rate, CO2 cyclic capacity, and heat
duty. The experimental results indicated that the addition of the
catalyst to the solvent regeneration process showed simultaneous increase
in CO2 desorption rate and cyclic capacity as well as reduction
of heat duty. The heat duty of the Ce(SO4)2/ZrO2 catalyst was 62 kJ/mol CO2, which required 56%
less energy for regeneration than without catalyst (110 kJ/mol CO2). The solid catalyst could help CO2 desorption
by providing free protons. The Ce(SO4)2/ZrO2 catalyst exhibited a much better performance than the HZSM-5
catalysts, as it possessed a strong acid site and a large amount of
Brønsted acid sites as well as a large pore size, which effectively
facilitated CO2 desorption.
The overall CO2 capture performance in terms of absorption
efficiency, heat duty, and cyclic capacity, as well as absorber overall
volumetric mass transfer coefficient (K
Gav) and desorber mass transfer coefficient (K
Lav) of BEA-AMP biblend amine solvent, in a bench-scale pilot
plant was evaluated and hugely enhanced by a combination of high-performing
absorber and desorber catalysts. Carbon nanotubes physically mixed
with K/MgO were incorporated in the absorber column while a solid
acid Ce(SO4)2/ZrO2 catalyst was incorporated
in the desorber column. The results showed that the addition of the
high-performance catalysts in both absorber and desorber columns resulted
in a huge improvement in the overall absorption and desorption processes
over those reported with K/MgO and HZSM-5. The absorber and desorber
catalysts greatly increased CO2 absorption efficiency,
cyclic capacity, mass transfer coefficient (K
Gav and K
Lav) and decreased the
relative heat duty in comparison with the noncatalytic system and
the case of having only HZSM-5 in the desorber catalyst. The desorber
catalyst facilitated amine regeneration for CO2 stripping
of the solution through proton donation leading to a tremendously
lower heat duty. The use of absorber catalyst resulted in a tremendous
improvement in the CO2 absorption process by donating electrons
and providing large specific surface areas to facilitate CO2 absorption.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.