Chrysotile As Catalyst for Sodium Dodecylbenzenesulfonate Degradation. Effect of Surfactant Concentration Above C.M.C.
Previous results showed that the aromatic ring of sodium dodecylbenzenesulfonate (SDBS) is degraded in the presence of chrysotile. We followed the degradation in concentrated SDBS aqueous solutions (3.0x10 -3 mol L -1 ) at 25 and 40 ºC. The turnover number (TON) of the reactions was calculated. Reductions in the surfactant concentration of 57.0% (TON=663) at 25 o C and of 40.0% (TON=409) at 40 o C were observed. A sample of chrysotile was used in sequential degradation reactions, showing a reduction of 15% (TON=750) in the SDBS concentration, after 4 cycles. The Infrared spectra of SDBS solutions dried after reaction with chrysotile showed no surfactant absorption bands.