Nitrate uptake from water by means of tailored adsorbents

G. V. NUNELL; M. E. FERNANDEZ; P. R. BONELLI; A. L. CUKIERMAN

WATER AIR AND SOIL POLLUTION

SPRINGER

Lugar: Berlin; Año: 2015 vol. 226 p. 1 - 13

0049-6979

Two different adsorbents directed tonitrate removal from water were developed from Parkinsonia aculeata wood. An activated carbon wasobtained by chemical activation with K2CO3 at 800 °C, whereas another adsorbentwas prepared using a dilute solution of NH4Cl at 450 °C. Elementalcompositions, surface functional groups, and textural parameters of bothadsorbents were determined and compared with those of a commercial activatedcarbon used as a reference. Nitrate adsorption assays were carried out toexamine the effects of solution pH, adsorbent dosage, contact time, andequilibriumadsorption isotherms. The adsorbent obtained with K2CO3 showed awell-developed pore structure (SBET=777m2/g; VT=0.35 cm3/g) and neutral character,while the one prepared with NH4Cl exhibited a low porous development (SBET=58m2/g; VT=0.03 cm3/g), acidic nature, and a noticeably high N content. Thelatter attained the highest nitrate removal efficiency, with amaximumadsorption capacity (XmL=0.40 mmol/g) higherthan those estimated for theformer (XmL=0.34 mmol/g) and the commercial sample (XmL=0.23 mmol/g), pointingto a predominant role of the chemical surface characteristics, mainly ofN-containing groups and basic functionalities. Accordingly, the adsorbentobtained with NH4Clrepresents a friendly novel material especially suited fornitrate removal.