Removal of Remazol Brilliant Blue R From Aqueous Solution by Pirina Pretreated with Nitric Acid and Commercial Activated Carbon

摘要

Pinna, a waste of olive oil factory, was used as an adsorbent for the removal of remazol brilliant blue R (RBBR) from aqueous solution by adsorption process. The pirina was pretreated with HNO_3 before batch adsorption experiments. The effects of contact time, initial concentration, pH, temperature, and ionic strength on dye removal were investigated. While the amount of the dye removed by the pirina was increasing with increasing initial concentration and temperature, it decreased with an increase in pH. Moreover, commercial activated carbon (CAC) was also used to compare with the pirina in removing the RBBR. The maximum amounts of the RBBR removed by the pirina and the CAC were 23.63 and 199.45 mg g~(-1) per unit mass of the adsorbents, and the removal efficiencies of them were found as 94.52 and 99.72 %, respectively. Ionic strength in the presence of NaCl and KC1 had also a reducing effect on the removal efficiency. The adsorption isotherm was in the best harmony with Langmuir, Freundlich, and Temkin models. The adsorption kinetic obeyed the pseudo-second-order and the intra-particle diffusion models. The values of the r~2 from the pseudo-second-order kinetic and intra-particle diffusion were between 0.984-0.999 and 0.85-0.996, respectively. From thermodynamic studies, it was seen that the adsorption was of spontaneous and endothermic nature. The values of AG° of the adsorption were between -3,218 and -8,867 J mol~(-1). The values of △H° and△S° were 50,134 J mol~(-1) and 179 J mol~(-1) K~(-1), respectively. Moreover, SEM and FT-IR studies were also performed.