Spatio-Temporal Perturbation of the Dynamics of the Ferroin Catalyzed Belousov−Zhabotinsky Reaction in a Batch Reactor Caused by Sodium Dodecyl Sulfate Micelles

详细信息    查看全文

• 作者：Federico Rossi ; Renato Lombardo ; Luciana Sciascia ; Carmelo Sbriziolo ; Maria Liria Turco Liveri
• 刊名：Journal of Physical Chemistry B
• 出版年：2008
• 出版时间：June 19, 2008
• 年：2008
• 卷：112
• 期：24
• 页码：7244 - 7250
• 全文大小：323K
• 年卷期：v.112,no.24(June 19, 2008)
• ISSN：1520-5207

文摘

The effects of the anionic surfactant sodium dodecyl sulfate (SDS) on the spatio-temporal and temporal dynamics of the ferroin-catalyzed Belousov−Zhabotinsky (BZ) reaction have been studied over a wide surfactant concentration range. For the first time, investigations were performed also for unstirred systems. The presence of SDS in the reaction mixture influences the oscillatory parameters to an extent that significantly depends on the surfactant concentration. The trend of the wave speed v upon the increasing amount of SDS was found to have a maximum at [SDS] = 0.075 mol dm⁻³ (v = 0.071 mm s⁻¹), after which the speed decreased to 0.043 mm s⁻¹ at [SDS] = 0.5 mol dm⁻³, which is below the value found in the absence of the surfactant (v = 0.055 mm s⁻¹). The response of the oscillatory BZ system to the addition of SDS has been ascribed to two different causes: (a) the peculiar capability of the organized surfactant assemblies to affect the reactivity by selectively sequestering some key reacting species and (b) the modifications induced by SDS on the physical properties of the medium. These hypotheses have been corroborated by performing spectrophotometric investigations on the stirred BZ system. Complementary viscosity measurements gave useful hints for the clarification of the surfactant role.