Arsenic (V) removal from aqueous solutions using natural clay ceramic monoliths

GARCÍA-CARVAJAL, C.; VILLARROEL-ROCHA, J.; CURVALE, D.; BARROSO-QUIROGA, M. M.; SAPAG, K.

CHEMICAL ENGINEERING COMMUNICATIONS

TAYLOR & FRANCIS INC

Año: 2019 vol. 206 p. 1440 - 1451

0098-6445

An adsorbent material arranged in a ceramic monolith (CM) obtained by extrusion techniqueusing natural bentonite and alumina (as raw materials) is presented. Ceramic and rawmaterials were characterized by X-ray fluorescence, thermal analysis, X-ray diffraction, andtextural analysis (with N2 adsorption?desorption at 77 K and Hg intrusion?extrusion porosimetry)to determine their chemical and physical properties. Then, As (V) adsorption capacityof the CM at different pH (3?9) using arsenic aqueous solution (with 2000 mg As (V) L1)was evaluated. Additionally, studies of kinetics and equilibrium of As (V) adsorption on CMwere performed. It was found that: (i) the As (V) removal capacity is favored at acidic pH,reaching an average value of 15 mg As (V) per gram of CM; (ii) from kinetic studies, As (V)adsorption on CM occur in two stages, the first of them reaching a lower As uptake in ashort time period, followed by an slow second stage with a subsequent higher As uptake,which continued for a longer time period, reaching equilibrium conditions in approximately24 h; and (iii) the As (V) adsorption isotherm is a type-Langmuir, indicating that the CM presentan homo quantity of fixed sites to adsorb the As (V).