Adsorption and Recovery of Tellurium from Aqueous Solutions Using Calcined Mg–Al Layered Double Hydroxide Adsorbent

There has recently been a rapid growth of domestic cadmium–tellurium (CdTe) photovoltaic (PV) solar panel production, mainly driven by the clean energy transition toward net-zero emissions. At the same time, the limited availability of tellurium (Te) underscores the importance of recovery practices for sustainable Te supply in the U.S. Herein, Mg–Al layered double hydroxide (LDH) demonstrated a high adsorption capacity for tellurium anion (TeO32–), offering high selectivity, efficiency, and recyclability in aqueous solution. Mg–Al LDH was synthesized via coprecipitation, and after calcination, a positive surface charge was developed on the adsorbent, resulting in surface adsorption and intercalation of tellurite anions (TeO32–) into the interlayer spaces of CLDH through electrostatic attraction. The synthesized calcined LDH (CLDH) achieved a maximum adsorption capacity of 161.8 mg/g at neutral pH, and 93% of adsorbed Te was recovered through NaOH-induced desorption. Therefore, Mg–Al LDH offers a potential solution for tellurium recovery, thereby promoting domestic CdTe solar panel production for a clean energy supply chain.