Synthesis of novel magnetic hydroxyapatite–biomass nanocomposite for arsenic and fluoride adsorption

SCHEVERIN, V. N.; DIAZ, E. M.; HORST, M. F.; LASSALLE, V. L.

ENVIRONMENTAL GEOCHEMISTRY AND HEALTH

SPRINGER

Año: 2024 vol. 46

0269-4042

hydroxyapatite and biomass (HAp–CM) was synthe-sized through a combined ultrasonic and hydrother-mal method, aiming for efficient adsorption of arsenic(As) and fluoride (F−) from drinking water in naturalenvironments. The characterization of HAp–CM wascarried out using TG, FTIR, XRD, SEM, SEM–EDS,and TEM techniques, along with the determinationof pHpzc charge. FTIR analysis suggested that coor -dinating links are the main interactions that allowthe formation of the nanocomposite. XRD data indi-cated that the crystalline structure of the constituentmaterials remained unaffected during the formationof HAp–CM. SEM–EDS analysis revelated a Ca/Pmolar ratio of 1.78. Adsorption assays conducted inbatches demonstrated that As and F− followed a PSOkinetic model. Furthermore, As adsorption fitting well to the Langmuir model, while F− adsorption could beexplained by both Langmuir and Freundlich models.The maximum adsorption capacity of HAp–CM wasfound to be 5.0 mg g−1 for As and 10.2 mg g−1 for F−.The influence of sorbent dosage, pH, and the pres-ence of coexisting species on adsorption capacity wasexplored. The pH significantly affected the nanocom-posite’s efficiency in removing both pollutants. Thepresence of various coexisting species had differenteffects on F− removal efficiency, while As adsorptionefficiency was generally enhanced, except in the caseof PO43−. The competitive adsorption between F− andAs on HAp–CM was also examined. The achievedresults demonstrate that HAp–CM has great poten-tial for use in a natural environment, particularly ingroundwater remediation as a preliminary treatmentfor water consumption.