The Investigation Of Chemical Oscillatory Reactions And The Treatment Of Organic Wastewater Relating To Chlorine Dioxide

This paper studies the ClO₂-â… ^--malonic acid(MA) chemical oscillatory reaction system by UV-vis spectrophotometric method.This reaction has an induced period. The amplitude increases along with the increase of the reaction time.Finally,the oscillation ceases suddenly.The initial concentration of malonic acid,chlorine dioxide, iodide and sulfuric acid has great influence on the oscillation.The equation of reaction rate changing with reaction time was obtained by differentiating the oscillatory curves in the oscillation stage.The amplitude and the period of oscillation changing with initial concentrations of various substances were discussed.It was observed that the number of oscillations is decreasing,the period of oscillation is increasing along with the increase of various substance's concentration without adding starch at 410nm.The oscillation phenomena can also be observed at 465nm,358nm and 299nm by adding starch.The oscillation becomes more obvious by adding starch than that observed without adding starch at 410nm.This paper also studies the ClO₂-â… ^--ethyl acetoacetate(EAA) chemical oscillatory reaction system by UV-vis spectrophotometric method.This reaction has an induced period.The amplitude increases along with the increase of the reaction time.Finally, the oscillation ceases suddenly.The initial concentration of ethyl acetoacetate,chlorine dioxide,iodide and sulfuric acid has great influence on the oscillation.The equation of reaction rate changing with reaction time was obtained by differentiating the oscillatory curves in the oscillation stage.The amplitude and the period of oscillation changing with initial concentrations of various substances were discussed.The oscillation phenomena can be observed at 461nm and 301nm by adding starch.The oscillation curves are similar each other under the two wavelengths.The oscillation becomes more obvious at 461nm than that at 301nm.The chlorine dioxide catalytic oxidization of acid chrome blue K simulated wastewater was investigated by using TiO₂ as catalyst.The optimum treatment condition was obtained.The COD removal efficiency and decolor efficiency were 38.9%and 78.4%,respectively,at the condition of pH value 1.2,the dosage of chlorine dioxide 1400mg/L,the dosage of TiO₂ 0.25g,reaction time 50min.The degradation mechanism of the wastewater compound was proposed by analysis the changes before and after treatment through UV-vis and FTIR spectrophotometer.The result indicated that chlorine dioxide catalytic oxidation was an efficient method to treat high concentration organic wastewater.This technology had great application prospect.