You can try buffers

Hi

Centrifuge, filtration washing, and decantation washing repeatedly with water is the best solution.

Normally NaOH is used in TiO2 processing, which has a high boiling point. Such basis are not removed even at high sintering temperatures, and they reduce the surface activity. These basis should be removed via filtration (use nano-filter)/centrifugation. If you will use any acid (e.g. acetic acid) to neutralize, the surface functionality and activity would be damaged. After complete removal of NaOH by the above methods, then make the solution pH slightly acidic (around 3 pH). TiO2 is readily aggregated in neutral conditions, however, slightly acidic conditions keep it stable/dispersed. You can use week acids with low boiling points, which are easy to separate/evaporate if needed.

Furthermore, if you want the best quality powder then you should use a freeze dryer to collect the powder, else TiO2 is again aggregated if the powder is made by the evaporation method.

Best regards.

Mumtaz Ali Thanks A lot for your precious time and reply. I am using HCL for minimizing the pH and will share the experience of HCL solution with You later InshaAllah

again thanks for your comment

You can try buffers

Shoaeb Mohammad Syed Thanks a lot dear for your precious suggestion. I used HCL solution for reducing the pH value.

acetic acid can help to reduce pH

In principle any strong acid (e.g. phosphoric, sulfuric, iodidric) acid that doesn't affect the compounds you are working with will be suitable.

Dear Muhammad Danish Ali, add concentrated HCl drop by drop with constant stirring and measure the pH after every drop.

the pH of a liquid solution can be reduced by concentrating the the solution which means minimizing the amount of water for adjusting it.

Dessie Ezez Thanks a lot for your Reply