Study on the Aggregation of Methylene Blue Molecule in Aqueous Solution
ZHANG Hong-man~*, CHEN Guo-song, TAO Xin, LU Xiao-hua(Department of Applied Chemistry, Nanjing University of Technology, Nanjing 210009)
The aggregation of methylene blue dye molecule in aqueous solution and its interaction with surfactants have been investigated by UV-Vis absorption spectroscopy. The effect of mineral salts on the aggregation of MB in the presence of anion surfactants has also been discussed. According to the dynamic equilibrium of MB monomer and dimer, the molar absorption coefficient of MB monomer (ε_m=5.90×10~4L·mol~(-1)·cm~(-1)) and the equilibrium constant of dimerazition (K′=6.38×10~3) have been obtained by computer programming method, which coincides well with the results from constructive method. Furthermore, the molar absorption coefficient of MB dimer (ε_d=1.22×10~5L·mol~(-1)·cm~(-1)) and the proportion coefficient of MB monomer in different concentrations have also been worked out.