In order to study the chemical oscillatory behavior and mechanism of a new chlorine dioxide–iodine–acetylacetone reaction system, a series of experiments were carried out by using UV–Vis and online FTIR spectrophotometric methods. The initial concentrations of acetylacetone, chlorine dioxide, iodine, sulfuric acid, and the pH value have considerable influence on the oscillations observed at wavelength of 350 nm for the starch–triiodide ion complex (\({\text{QI}{_{3}^-}}\)). There is a pre-oscillatory or induction stage, the amplitude and the number of oscillations are associated with the initial concentration of reactants. Equations were obtained for the starch–triiodide ion complex (\({\text{QI}{_{3}^-}}\)) reaction rate change with reaction time and the initial concentrations in the oscillation stage. The oscillation reaction can be accelerated by increasing the reaction temperature. The apparent activation energies at the induction stage and the oscillation stage are 45.64 and 12.39 kJ·mol−1, respectively. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

A novel cationic asphalt emulsifier N,N-dimethyl-N-(oxiran-2-ylmethyl)octadecan-1-aminium chloride was synthesized by reaction of epichlorohydrin and N,N-dimethyloctadecylamine. The optimum reaction condition was obtained. The yield and epoxy group value reached 98.0 and 41.8 %, respectively, at the optimum conditions: reaction temperature of 50 °C, reaction time of 5 h, and feedstock mole ratio of epichlorohydrin to N,N-dimethyloctadecylamine of 1.2. The chemical structure of the emulsifier was confirmed by Fourier-transform infrared (FTIR), 1H nuclear magnetic resonance (NMR), and elemental analysis. The synthesis process was monitored by the online FTIR technique. The by-product was detected by online FTIR analysis. Based upon the experimental data, a plausible reaction mechanism is proposed for the reaction. The critical micelle concentration (CMC) of the emulsifier has a lower value of 4.35 × 10−4 mol/L. The surface tension at CMC is 28.51 mN/m. The emulsifier exhibits satisfactory emulsification. The prepared bituminous emulsion showed higher storage stability. The emulsifier belongs to the class of medium-set asphalt emulsifiers.

In order to study the chemical oscillatory behavior and mechanism of a new chlorine dioxide–iodine–ethyl 2-chloroacetoacetate reaction system, a series of experiments were carried out by using UV–Vis and online FTIR spectrophotometric methods. The initial concentrations of ethyl 2-chloroacetoacetate, chlorine dioxide, iodine, sulfuric acid, and the pH value have great influence on the oscillations observed at wavelength of 585 nm for the starch–triiodide complex (\( \text{QI}_{3}^{ - } \)). There is a pre-oscillatory or induction stage, the amplitude and the number of oscillations are associated with the initial concentration of reactants. Equations were obtained for the starch–triiodide complex reaction rate change with reaction time and the initial concentrations in the oscillation stage. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

In order to study the chemical oscillatory behavior and mechanism of a new chlorine dioxide–iodide ion–methyl acetoacetate reaction system, a series of experiments were done by using UV–vis and an online FTIR spectrophotometric method. The initial concentrations of methyl acetoacetate, chlorine dioxide, potassium iodide, sulfuric acid, and the pH have great influences on the oscillations observed at the wavelength 350 nm. There is a pre-oscillatory or induction period, and the amplitude and number of oscillations are dependent on the initial concentration of the reactants. Equations were obtained for the variation of the triiodide ion reaction rate with the reaction time and the initial concentrations in the oscillation stage. The oscillation reaction was accelerated by increasing the temperature. The apparent activation energies for the induction period and the oscillation period are 55.65 and 33.00 kJ·mol−1, respectively. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism is proposed for the oscillation reaction.

A novel betaine-type asphalt emulsifier, 3-(dodecyloxy)-2-hydroxypropan-N-carboxymethyl-N,N-dimethylammonium chloride, has been synthesized in a three-step reaction from lauryl alcohol, epichlorohydrin, dimethylamine, and chloroacetic acid. The optimum reaction conditions were obtained for synthesis of 2-(dodecyloxymethyl)oxirane in the first step. The yield reaches 75.7 % under the optimum conditions of reaction temperature 50 °C, reaction time 5 h, feedstock mole ratio of epichlorohydrin to lauryl alcohol 1.4, basicity 33.3 %. The structures of the three products were identified by FTIR. Synthesis of 2-(dodecyloxymethyl)oxirane in the first step was monitored by online FTIR, and an intermediate was detected. On the basis of the experimental data, a plausible reaction mechanism was proposed for the reaction. The critical micelle concentration (CMC) of the final product is low, 8.8 × 10−5 mol/L. The surface tension at the CMC is 21.2 mN/m. This product is an excellent emulsifier for asphalt. The prepared bituminous emulsion had high storage stability. The emulsifier is a rapid-set asphalt emulsifier.

A new chlorine dioxide–iodine–sodium thiosulfate chemical oscillatory reaction was studied by the UV–Vis spectrophotometric method. The initial concentrations of sodium thiosulfate, chlorine dioxide, iodine, sulfuric acid, and pH have great influences on the oscillations observed at wavelength 238 nm. The oscillations occur as long as the reactants are mixed. The amplitude and the number of oscillations are associated with the initial concentrations of reactants. The equations for the triiodide ion reaction rate changes with reaction time and the initial concentrations in the oscillation stage are an attenuation sine function. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

An activated carbon-MnO2 catalyst was prepared and used for chlorine dioxide catalytic oxidation of simulated o-chlorophenol wastewater. The COD removal efficiencies of chemical oxidation and catalytic oxidation are 28.6 and 93.5%, respectively. The COD removal efficiency of catalytic oxidation is greater than that of chemical oxidation at the same treatment condition. By using UV–Vis and online FTIR analysis technique, the intermediates during the degradation process were obtained. The benzene ring in o-chlorophenol was degraded into quinone and carboxylic acid, and finally changed into carbon dioxide and water during the catalytic oxidation. The degradation reaction mechanism of o-chlorophenol by chlorine dioxide catalytic oxidation was proposed based upon the experiment evidence.

The appearance of oscillations for the closed system ClO2–I2–ethyl acetoacetate depends critically on the pH in the absence of sulfuric acid, and was investigated by determining changes in the absorbance of \(\mathrm{I}_{3}^{ -}\) with reaction time at the wavelength 280 nm. The pH should be 2.2–3.8 for this reaction. The initial concentrations of ethyl acetoacetate, chlorine dioxide, iodine and sulfuric acid have great influences on the oscillations observed at wavelengths of 280 nm or 350 nm. The oscillations at 280 nm occur as long as the reactants are mixed. However, at 350 nm the oscillation is preceded by a pre-oscillatory or induction period. The oscillation curve is more regular and smooth at 350 nm than that at 280 nm. The amplitude and the number of oscillations are associated with the initial concentration of each reactant. (1) The higher the initial concentration of ethyl acetoacetate, the greater is the amplitude while the number of oscillations becomes smaller. The amplitude is small at the beginning stage but increases with reaction time. An opposite influence exists for chlorine dioxide. Finally, the oscillation suddenly ceases. (2) When the initial concentration of iodine is higher, the amplitude is small at the beginning stage but then increases with reaction time. When the initial concentration of iodine is lower, the amplitude is large at the beginning stage and then decreases with reaction time. An opposite influence exists for sulfuric acid. Equations for the triiodide ion reaction rate were obtained as functions of reaction time and initial concentrations at the oscillation stage. The intermediates were detected by online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

The sodium chlorite–iodine–ethyl acetoacetate (EAA) chemical oscillatory reaction system was studied by UV–Vis and online FTIR spectrophotometric method. The oscillation phenomenon does not occur as long as the reactants are mixed. There is a pre-oscillatory or induction period. The amplitude is small at the beginning stage and then increases with reaction time. Finally, the oscillation ceases suddenly. The amplitude and the number of oscillations are associated with the initial concentration of sodium chlorite, iodine, EAA and sulfuric acid. The equations for the triiodide ion reaction rate changing with reaction time and the initial concentrations on the oscillation stage were obtained. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

The appearance of oscillations depends critically on the pH for a closed system of ClO2–I2–ethyl acetoacetate in the absence of sulfuric acid, and was investigated by determining the absorbance of I3− with reaction time at 280 nm. The pH should be 2.2–3.8. The initial concentration of ethyl acetoacetate, chlorine dioxide, iodine, and sulfuric acid has great influence on the oscillation at 581 nm for I3−–starch complex (SI3−). The oscillation occurs as long as the reactants are mixed at 280 nm. There is no pre-oscillatory period. However, at 581 nm, there is an induction period. The curve’s shape at 581 nm is very different from that at 280 nm. The oscillation becomes more obvious by adding starch at 581 nm for I3−–starch complex (SI3−) than that observed without adding starch at 280 nm. The oscillation curve is more regular and smooth by adding starch at 581 nm than that without adding starch at 280 nm. The amplitude and the number of oscillations are associated with the initial concentration of reactants. The higher the initial concentration of ethyl acetoacetate, the bigger the amplitude. Also, the number of oscillations becomes small. An opposite influence exists for chlorine dioxide and iodine. The higher the initial concentration of sulfuric acid, the bigger the amplitude. Also, the number of oscillations becomes large. The equations for the triiodide ion reaction rate changing with reaction time and the initial concentrations on the oscillation stage were obtained. The intermediates were detected by the online FTIR analysis. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.

The appearance of oscillations depends critically on the pH for the closed system ClO2-I2-malonic acid in the absence of sulfuric acid, and was investigated by determining the absorbance of I3− with reaction time at 280 nm. The pH should be 3.2–3.8. The initial concentrations of malonic acid, chlorine dioxide, iodine and sulfuric acid have great influence on the oscillation at 280 or 350 nm. The oscillation occurs as long as the reactants are mixed at 280 nm. However, at 350 nm the oscillation is preceded by a pre-oscillatory or induction period. The amplitude is small at the beginning stage but then increases with the reaction time. Finally, the oscillation ceases suddenly. The amplitude and the number of oscillations are associated with the initial reactant’s concentration. The higher is the initial concentration of malonic acid, iodine or sulfuric acid, the bigger is the amplitude. Also, the number of oscillations becomes small. An opposite influence exists for chlorine dioxide. The oscillation curve is more regular and smooth at 350 nm than that at 280 nm. The oscillation becomes more obvious by adding starch at 581 nm for I3−–starch complex (SI3−) than that observed without adding starch at 280 nm. The curve’s shape at 581 nm is very different from that at 280 or 350 nm. The equation for the triiodide ion reaction rate changing with reaction time and the effect of initial concentrations on the oscillation stage were obtained. Based upon the experimental data in this work and in the literature, a plausible reaction mechanism was proposed for the oscillation reaction.