title: Amorphous boron-doped sodium titanates hydrates: Efficient and reusable adsorbents for the removal of Pb2+from water.
abstract: Amorphous titanium hydroxide and boron-doped (B-doped) sodium titanates hydrates were synthetized and used as adsorbents for the removal of Pb2+from water. The use of sodium borohydride (NaBH4) and titanium(IV) isopropoxide (TTIP) as precursors permits a very easy synthesis of B-doped adsorbents at 298K. The new adsorbent materials were first chemically characterized (XRD, XPS, SEM, DRIFT and elemental analysis) and then tested in Pb2+adsorption batch experiments, in order to define kinetics and equilibrium studies. The nature of interaction between such sorbent materials and Pb2+was also well defined: besides a pure adsorption due to hydroxyl interaction functionalities, there is also an ionic exchange between Pb2+and sodium ions even working at pH 4.4. Langmuir model presented the best fitting with a maximum adsorption capacity up to 385mg/g. The effect of solution pH and common ions (i.e. Na+, Ca2+and Mg2+) onto Pb2+sorption were also investigated. Finally, recovery was positively conducted using EDTA. Very efficient adsorption (>99.9%) was verified even using tap water spiked with traces of Pb2+(50ppb).
authors: CNR-IRSA, Via de Blasio 5, 70132 Bari (BA), Italy.
authors: Luigi
authors: L
authors: di Bitonto
authors: CNR-IRSA, Via de Blasio 5, 70132 Bari (BA), Italy.
authors: Angela
authors: A
authors: Volpe
authors: CNR-IRSA, Via de Blasio 5, 70132 Bari (BA), Italy.
authors: Michele
authors: M
authors: Pagano
authors: CNR-IRSA, Via de Blasio 5, 70132 Bari (BA), Italy.
authors: Giuseppe
authors: G
authors: Bagnuolo
authors: CNR-IRSA, Via de Blasio 5, 70132 Bari (BA), Italy.
authors: Giuseppe
authors: G
authors: Mascolo
authors: CNR-ISMN, Via U. La Malfa, 153, 90146 Palermo (PA), Italy.
authors: Valeria
authors: V
authors: La Parola
authors: CNR-IMAA, Via S. Loja, Tito Scalo (PZ), Italy.
authors: Paola
authors: P
authors: Di Leo
authors: CNR-IRSA, Via de Blasio 5, 70132 Bari (BA), Italy. Electronic address: carlo.pastore@ba.irsa.cnr.it.
authors: Carlo
authors: C
authors: Pastore
keywords: Adsorption; Ionic exchange; Metal removal; Pb(II); Titanium hydroxides