UV-VIS studies on interaction between sodium dioctylsulfosuccinate (AOT) and methyl red

Abstract

"This paper deals with the interaction of sodium dioctylsulfosuccinate (AOT) and methyl red (MR) by UV-Vis spectrophotometry at 298.15 K. The concentration of AOT varies from 0 to 0.12530 mol/kg and the concentration of methyl red is 3.71×10-5 M. Here, water concentration is defined by the R parameter. The R parameter in this study varied from 0 to 20. Two intense absorption bands were observed within the 380 to 540 nm wavelength of methyl red in methanol. Band 1(380 to 450 nm) of methyl red contains a higher absorbance peak than band 2(450 to 540 nm). When the concentration of AOT increased, band 1(380 - 450 nm) of methyl red decreased the absorbance peak, whereas band 2 (450 to 540 nm) of methyl red increased the absorbance peak with increasing AOT concentration. Band 1 shows a hypochromic shift of methyl red with an increase in AOT concentration, whereas band 2 shows a hyperchromic shift of methyl red with an increase in AOT concentration. On comparing the absorbance versus concentration graph for different R parameters, we observed that absorbance increases with the increase in the R parameter. The binding constant and distribution constant were calculated using a non-linear regression procedure (NLREG). The experiment shows the effect of methanol, AOT and water concentration on methyl red."

Removal of Methyl Red from Aqueous Solution Using Biochar Derived from Fennel Seeds

“…The enhanced adsorption of methyl red on adsorbent surfaces could be attributed to the properties inherent within the molecule. Specifically, when in the presence of protons, the methyl red molecule exhibits both a positive charge on the nitrogen atom and a negative charge in the form of the -COO − group (Figure 6) [21]. As a result of this dual charge structure, the dye molecule is capable of interacting with both acidic and basic oxygen groups on the surface of the biochar.…”