Efficient Removal of Uranium (VI) by One-Step Synthetic Environmentally Friendly Hydroxyapatite Modified Attapulgite Composite Material: Adsorption Properties and Mechanism Studies

A one-step hydrothermal method was successfully employed to synthesize hydroxyapatite modified attapulgite composite material (HAP/ATP), which was characterized to determine physicochemical properties. Furthermore, the performance and mechanism of uranium removal by HAP/ATP were extensively investigated. Results indicated that HAP/ATP reached adsorption equilibrium for uranium at around 20 min with a maximum adsorption capacity of 387.27 mg·g⁻¹. Modern characterization techniques identified ion exchange, complexation, dissolution–precipitation, and electrostatic adsorption as the primary mechanisms for uranium removal by HAP/ATP. ATP, a type of clay mineral, possesses a large specific surface area and natural pores. When utilized as a carrier, ATP reduced agglomeration of load materials. HAP can introduce more adsorption functional groups for attapulgite, this is a synergy, exerting the complementarity of materials. HAP/ATP demonstrates promising potential as an environmentally friendly adsorbent material for the treatment of radioactive uranium-containing wastewater.