A facile synthesis of ibandronate modified hydroxyapatite renewable nanomaterials for simultaneous removal of Cu2+/Pb2+ and chlortetracycline: Experimental design and adsorption mechanism study

A simple co-precipitation method was used to synthesize ibandronate nano-functionalized hydroxyapatite (IB-HAP) and used for the removal of Pb2+/Cu2+ and chlortetracycline. The effects of the amount of modifier IB added, the initial concentration and the pH value of the solution on the adsorption effect of heavy metal ions were investigated. When the P atom in IB accounts for 5% of the total phosphorus, the adsorption capacity of IB-HAP was 1565.3 mg/g (Pb2+) and 246.71 mg/g (Cu2+), respectively. By adding heavy metal ions and chlortetracycline (CTC) in different addition sequences, the co-adsorption effect of various pollutants on IB-HAP was studied. According to microstructure analysis and simulation, the adsorption mechanism was studied from a microscopic point of view. It is the first time that modifiers and pollutants were used as central molecules to study the interaction sites and interaction strengths with surrounding molecules in a wholly covered state by Hirshfeld surface analysis. Finally, the desorption experiments showed that IB-HAP had strong regeneration and sustainability. These results showed that IB-HAP was a potential adsorbent, and this study also provided new guidelines and valuable methods for analyzing the mechanism of co-adsorption of heavy metal ions and antibiotics.