resumo
The rice husk ash (RHA) was used as an alternative source of silica for the synthesis of the functionalized mesoporous material, which was used in the removal of the PAHs naphthalene (Nap), benzo[b]fluoranthene (B[b]F), benzo[k]fluoranthene (B[k]F), and benzo[a]pyrene (B[a]P) from aqueous media. The PABA-MCM-41 (RHA) was characterized using FTIR, TGA, SAXS, and N-2 adsorption-desorption analyses. Removal experiments were performed to determine the initial concentrations, individual adsorption in comparison with the mixture of the PAHs, PABA-MCM-41 (RHA) amount, pH, time, and temperature, and the results obtained were statistically analyzed. The PABA-MCM-41 (RHA) presented the S-BET, V-T, and D-BJH values of 438 m(2) g(-1), 0.41 cm(3) g(-1), and 3.59 nm, respectively, and good thermal stability. The q(e) values found in the kinetic equilibrium for the PAHs mixture followed increasing order: Nap < B[a] P < B[k]F < B[b]F, with removal percentages of 89.08 +/- 0.00, 93.85 +/- 0.28, 94.54 +/- 0.10, and 97.80 +/- 0.05%, respectively.
palavras-chave
EFFICIENT ADSORPTION; PAHS; MCM-41; WATER; OXIDE; DYES
categoria
Environmental Sciences & Ecology
autores
Costa, JAS; Sarmento, VHV; Romao, LPC; Paranhos, CM
Grupos
agradecimentos
This work was supported by FAPESP (Research Support Foundation of the State of Sao Paulo) (Grants 2014/05679-4, 2017/06775-5, and 2018/18894-1), CAPES (Coordination for the Improvement of Higher Education Personnel) (Grant 309342/2010-4), and CDMF (Center for the Development of Functional Materials) (Grant 2013/07296-2) for the financial support and LNLS for the SAXS measurements (Project SAXS1 12642).