I am working of photocatalysis of PS organics with a particle size of 29 nm and use TiO2 with particles size of 10-20 nm. The suspension is in deionized water. How can I separate them and recover TiO2 after reaction?
Hi Ahmad,
In your question it is not clear what is the material with the acronym PS. It would be helpful if you could provide more information.
That said, I would first try to centrifuge to remove the supernatant and re-suspend the particles in something that can dissolve the organic nanoparticles. Thereafter, you would need to repeat the process (centrifuge, re-suspension) untill all organic particles are removed.
Alternately, you could also try burning the residue in air to remove organic compounds, but that could affect the TiO2 nanoparticles.
I hope this helps.
Kind regards
Are you interested in recovering the PS beads? If not, you could, for instance, try centrifuging and washing the precipitate with a solvent for PS, such as toluene or THF.
Thank you. Yes, I only want to recover TiO2. I am thinking about centrifugation, but is there any proximate calculation for the centrifuge at least to near precise rpm and time or shall I just do trial and error method?
I would typically just try 15 min at different speeds. I usually do it over 15 min intervals at 2000 rpm depending on how clean my supernatant looks.
Dear Ahmad,
Given the different size and density (and probably also shape) of PS and TiO2, you could try differential centrifugation or density gradient centrifugation. You can modify both methods to suit your purpose doi: 10.1038/srep27494 .
