Study of adsorption of uranium from wastewater by attapulgite - yeast powders adsorbent grains

Preparation method of attapulgite-yeast powders adsorbent grains is studied by using yeast powders as pore former and sodium silicate as binder. The optimizing process is activating the attapulgite with 5% of HCl for 24h, dissolving 15% pore-former and 2% binder with the acid attapulgite, baking the grains at 600°C for 1h. Attapulgite-yeast powders adsorbent grains reach equilibrium on adsorption of uranium in 30min. The adsorbent percentage is 99.5% when the concentration is 10mg·L^-1. When the concentration is 200mg·L^-1, the adsorbent capacity is 35.1mg·g^-1. The attapulgite-yeast powders adsorbent grains can be regenerated many times. The operation is simple and no secondary pollution is produced.