Tailoring Sepiolite for Efficient CO<sub>2</sub> Desorption: A Sustainable Approach Utilizing Acid Activation for Amine Regeneration Optimization
Minhua Li, Ali Hassan Bhatti, Ting Li, Mamoona Waris, Yingjie Niu, Xin Zhou, Li Luo, Chao’en Li, Francesco Barzagli, Rui Zhang
Abstract
In the context of industrial CO 2 capture, the need for efficient solvent regeneration at lower temperatures poses a significant challenge. Catalyst-assisted enhancement of the CO 2 desorption kinetics has emerged as a potential solution. This study introduces a series of cost-effective and readily available sepiolite clay-based catalysts activated via simple acid treatments. This activation significantly enhances both the surface area and surface acidity, laying the foundation for more effective catalysts. Experimental results at a moderate temperature of 88 °C demonstrate the effectiveness of the prepared catalysts, resulting in remarkable improvements: up to a 163.6% increase in the CO 2 desorption rate, an up to 83.6% increase in the desorbed CO 2 quantity, and a reduction of up to 45.6% in heat duty compared with the baseline amine solution. Furthermore, the prepared catalysts exhibit facile separability through filtration and sustained stability over 10 cycles. To shed light on the underlying chemical processes, we also present a plausible reaction mechanism for the acid-activated sepiolite-catalyzed CO 2 desorption reaction. This research holds promise for environmentally friendly and cost-effective amine regeneration processes in CO 2 capture applications.