Rubik’s cube-shaped Linde type A zeolite synthesized from biomass for carbon dioxide capture
Chen Zhang, Duoyong Zhang, Xinqi Zhang, Xiaoou Chen, Linrui Chen, Yongqiang Tian, Liwei Wang
Abstract
Materials with tunable properties are crucial for mitigating CO 2 emissions. Here, uniform and well-structured porous Rubik's cube-shaped Linde type A (LTA) zeolites are synthesized for CO 2 capture, representing advancement in eco-friendly and cost-effective materials. The synthesis procedure extracts melting silicon from silicon-rich biomass ashes, followed by template-free hydrothermal synthesis. The melting approach is proposed to collect silicon for high hydroxide anion concentration and outstanding flowability, accelerating reaction kinetics and yielding alkaline silicon-containing solutions to promote crystallization of zeolites. These zeolites possess CO 2 sorption capacity (2.97 mmol/g at 1 bar and 298 K) and selectivity for CO 2 /N 2 (around 255.1), influenced by ultramicropores with heterogeneous surfaces containing metal ions. Cyclic robustness during vacuum temperature swing cycles displays a low attenuation rate (approximately 7.7% over 20 cycles). Thus, Rubik's cube-shaped LTA zeolites are a promising and cost-effective approach to addressing CO 2 capture challenges by leveraging readily available biomass materials.