Performance of surfactant-modified activated carbon prepared from dates wastes for nitrate removal from aqueous solutions

New material (AC-CTABr) was successfully prepared from chemical activation of dates wastes (AC), followed by cationic surfactant modification and was used to enhance nitrate removal from aqueous solutions. Brunauer, Emmett and Teller (BET) analysis revealed good binding of quaternary ammonium groups on the surface (1407 m(2)/g for the AC and 569 m(2)/g for the AC-CTABr). Batch experiments were conducted to examine the effect of contact time, solution pH, adsorbent dose, and initial concentration of nitrate. Preliminary results showed an improvement of nitrate removal from 14% to 60% for the AC and the AC-CTABr, respectively. Also, the adsorption kinetic was very fast; the equilibrium was achieved within the first 5 min of contact time between the adsorbents and the nitrate solution. Application of several isotherm models has shown that Langmuir and Freundlich models described well the experimental data with a maximum adsorption capacity of 83.33 mg/g. Three simplified kinetic models were tested to investigate the adsorption mechanism. The pseudo-second order model was found to describe adequately the experimental kinetic data. Results showed that the new adsorbent material is a suitable adsorbent for nitrate removal. (c) 2018 American Institute of Chemical Engineers Environ Prog, 38: S403-S411, 2019