Cost effective separation of uranium ion using exhausted household products and natural bio-sorbent

Dried coconut leaf, Exhausted tea leaf and coffee powder were used to demonstrate the cost effective sorption of UO₂²⁺ ion from aqueous solution. The K_d followed the order: coconut leaf > tea leaf > coffee powder. The sorption mechanism was evaluated by linearly fitting the experimental data into different isotherm models: Langmuir, Dubinin-Radushkevich, Freundlich and Tempkin isotherm. Similarly, the sorption kinetics were also modelled. The extraction followed Langmuir isotherm, chemisorption and pseudo second order rate kinetics. The sorption was spontaneous, energetically favourable, endothermic and entropically driven in nature. Sodiumcarbonate was more efficient for stripping of uranyl. The biosorbent showed good radiolytic stability. (author)