Characterization of new adsorbent prepared from apricot stones activated carbon mixed with amorphous SiO2 from Algerian diatomite for removal of p-nitroaniline

This work aims to evaluate the adsorption efficiency of p-nitroaniline (PNA) onto apricot stones activated carbon (ASAC) mixed with treated extract of amorphous SiO2 (TEAS), prepared from Algerian diatomite (AD). The best removal percentage (85%) is obtained for a ratio ASAC/TEAS (1/1). Adsorbent characteristics are investigated by the Brunauer-Emmett-Teller (BET), the scanning electron microscope (SEM), infrared spectroscopy (IR), X-ray fluorescence (XRF) and X-ray diffraction (XRD). The impregnation of TEAS and ASAC produces good adsorbent properties towards PNA especially in the ratio (1/1) and an increase in the specific surface. The isotherm data are well fitted by the Langmuir and Freundlich models. The maximum PNA uptake obtained is 94.34 mg g-1. The performances of ASAC/TEAS for the PNA adsorption were compared with some adsorbents previously studied for the same purpose, and results show that the composite in the present work exhibit better performances. The adsorption behavior of the concerned material is explained on the basis of its chemical nature and porous texture.