Abstract
Empirical adsorber design using adsorption equilibrium conditions is necessary to predict its size and performance. Single-stage batch adsorption is the most commonly method used by researchers to evaluate their adsorbents for commercial usage. However, further studies are needed to assess the adsorbent application at industrial field. KOH-oxidized rice straw-based carbon (RSK) has been investigated for adsorption of U(VI) in a single batch adsorber. An initial uranium concentration of 100 mg/l is assumed and the required amount of carbon to recover U(VI) content by 5%-95% was calculated. For example, the required masses of RSK carbon to treat 50 L of 100 mg/l of uranium solution are 4.0, 13.0, 24.0, 39.0, 69.0 and 89.0 g for 5%, 10%, 30%, 50%, 70%, and 90% U(VI) removal, respectively. Through such a projection, a real single stage adsorption system can be design. Two-stage batch adsorber design model was further developed to predict the minimum amount of RSK carbon necessary to reach a specific uranium removal percentages at a given volume of wastewater effluents. The replacement of single-stage system with two-stage system results in significant reduction (25%) of the overall required sorbent amount that balances the higher cost of the two-stage plant.