From the synthetic clays to their natural counterparts – how to scale up capture of CO₂ and dye contaminating rivers

Capture of CO₂ and cleaning of rivers from polluting dyes, which is the huge ecological problem mainly in developing countries, are ecological challenges of the present and future.



We demonstrated that capture of CO₂ ^1–5 and dyes is possible with synthetic fluorohectorite clay (Fht). Fht is composed of 1 nm thin negatively charged layers that are kept together by interlayer cation, so intercalation of any positively charged molecule, or molecules with dipole and quadrupole moment is possible.

Even if mechanism of capture is well known, scale-up is needed for real-world use and applications.



In order to do that, we transferred the focus from the Fht to natural vermiculite clay. As the charge of the single-layer vermiculite nanosheets is much higher than that of Fht, we had to find mechanism how to open structure and allow molecules to enter the interlayer. We demonstrated that structure can be opened using solvents such as DMF, NMF and DMSO, and further delaminated into the single nanosheets, by performing in-situ synchrotron-diffraction experiments and AFM. Challenges and solutions of this problem are discussed in a view of dynamics of opening the vermiculite interlayer towards its practical use in the capture of molecules.







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