scotty

Hi All, so, I'm not even a science novice lol I just have scoured Google for my answer and come up blank. I was hoping you guys could help? So I've seen the chemical process of how Aluminum Oxide is made, but little information can be found about it's activation. Fluoride is a major problem in India and activated alumina is widely used to treat their drinking water, so some info can be found from them. They reactivate it every 3 months using this method: *Mix 8 liters of clean water with 80 grams of sodium hydroxide (Lye) in a bucket, leave for 8 hours *Then Clean with 8 buckets of clean water *Mix 8 liters of clean water with 80 ml of Sulphuric Acid, leave for 8 hours *Then Clean with 8 buckets of clean water I have also seen that, when used as a desiccant, you can reheat the media to 200 degrees celsius to regenerate it. My questions are: 1. Is the base/acid re-activation process the only one? and 2. What exactly happens, chemically, when the aluminum oxide is activated? What makes it activated? 3. Would you imagine that there is a cheaper way to reactivate A.O. on a global scale for filtering fluoride and arsenic? Thanks!