Ultra-stable alkyne-bridged thulium ion-imprinted polymers for acid-resistant and selective recovery of rare earth elements from industrial wastewater

• Alkynyl-bridged network resists 6 M HCl, enabling ultra-stable REE recovery. • Record Tm 3+ /La 3+ selectivity (separation factor: 161) via size-matched cavities. • High Tm 3+ uptake (58.6 mg/g) outperforms conventional acidic adsorbents. • Functional stability in 1 M HCl (12.6 mg/g) supports industrial applications. The recovery of rare earth elements (REEs) from acidic industrial wastewater remains a critical challenge due to the instability and poor selectivity of conventional adsorbents. Here, we present a novel alkyne-bridged thulium ion-imprinted polymer (De-Po-Tm-0.33) designed via dynamic covalent anchoring and π-conjugate stabilization strategies. De-Po-Tm-0.33 has a maximum adsorption capacity of 58.6 mg/g, which is superior to most existing adsorbents. Remarkably, it exhibits ultrahigh selectivity with a Tm 3+ /La 3+ separation factor of 161, the highest reported value for REEs separation systems. The material retains 95 % capacity after 10 adsorption–desorption cycles, attributed to the robust alkyne network and reversible Tm-O coordination. The experimental results confirmed its excellent performance (12.6 mg/g) in harsh conditions (1 M HCl), demonstrating a groundbreaking approach for sustainable REE recycling under extreme industrial conditions.