MACIEL, T. A. R.; http://lattes.cnpq.br/9370544881238927; MACIEL, Tamara Aline Ramos.
Resumo:
Adsorption is a surface phenomenon where mass transfer occurs in which substances in liquid phase are adsorbed or accumulated in the solid phase, and thus removed from the liquid phase. This work aims at performing adsorption experiments to evaluate the activated carbon produced from black Jurema (Mimosa tenuiflora (Willd.) Poiret), chemically treated with sodium hydroxide (NaOH) and carbonized at times and temperatures. For the evaluation of samples (A, B and C) Adsorption tests were performed with methylene blue dye at a concentration of 10 mg.L-1, depending on the time variable. Samples of 0.2 g of coal along 30ml dye isothermally were stirred at a speed of 150 rpn at 24 hour period. After this period, the absorbance was determined for each sample in a spectrophotometer in the visible region (660 nm). The values obtained showed that all the samples showed an unsatisfactory removal rate , but the sample A obtained a value greater than about 99.06 % removal , indicating that the temperature 400th carbonized during 180 min was the most efficient , thus this sample must be used for further studies. In the analysis of the contact time between the adsorbent and the adsorbate, held in the three sample and in triplicate , it was observed that in the first 5 minutes of contact was a very significant removal efficiency for the three samples , but the sample A removed immediately 94,46 % of the adsorbate, about 10 % love the samples B and C. By applying the Langmuir was observed that the results were favorable in all the samples, wherein the correlation coefficients (R2) are those close to 1, which is ideal. When we used the model of Freundlich, it was evident that some points were well away from the linear regression, implying a R2 they are significant.Thus it can be concluded that the activated carbon produced from black Jurema (Mimosa tenuiflora (Willd.) Poiret) is suitable for the adsorption of methylene blue dye.
