Activated carbons developed in different activation conditions to improve nitrate adsorption performance

S. ROMAN; B. LEDESMA; M. E. FERNANDEZ; G. V. NUNELL; P. R. BONELLI; A.L. CUKIERMAN

BOLETIN ESPAÑOL DEL CARBON

Grupo Español del Carbón

Lugar: Oviedo; Año: 2016 vol. 42 p. 16 - 21

2172 6094

The suitability of activated carbons (ACs) with dissimilar textural and surface chemistry characteristics was studied for nitrate removal, under different pH conditions. For this task, four ACs were used; two of them were manufactured by chemical and physical steam activation from orange peel and almond shell, while the other two were commercial adsorbents. It was found that both the precursor and activation methodology influence the adsorbents characteristics. Regarding nitrate uptake, their chemical surface was very relevant, while the textural properties did not exert a remarkable effect. Also, nitrate adsorption under acid pH was improved, especially for basic adsorbents, in contrast with neutral conditions, in which case no adsorbent stood out. The amelioration of nitrate removal for basic adsorbents and acidic pH conditions was associated to agreater prominence of electrostatic contributions as well as a lower extent of adsorption competition between hydroxyl and nitrate ions.