Kinetics humic degradation

The formation of scavenger substances can also retard removal efficiency and kinetic reaction rates. Scavengers are ions such as bicarbonate, carbonate, chloride, and humic acid, etc. These scavengers subsequently react with hydroxyl radicals produced during the degradation process. Therefore, the removal efficiency will be reduced significantly. In the presence of scaveng-... 

A pseudo first-order reaction with a half-life of 2 h was deduced for the photooxidation kinetics of anthracene in aqueous media under simulated solar radiation conditions [11]. Bertilsson and Anneli report that photochemical degradation of anthracene and phenanthrene in water proceeds rapidly (half-lives 1 and 20.4 h, respectively) while that of naphthalene (half-life > 100 h) does not [12], In the presence of humic substances, the anthracene degradation rate was unaffected while that of phenanthrene was slowed down considerably. Differences in the spectral absorbance of anthracene and... 

The surfaces of Mn oxides promote the oxidative polymerization of many polyphenolics, the polycondensation of pyrogallol and glycine, and the formation of humic substances. Many organics are oxidatively decomposed by Mn oxides during the reduction of Mn(III) or Mn(IV). The role of Mn oxides in C turnover and N transformations should, thus, be studied in depth. Besides natural organics, the kinetics of the degradation of certain xenobiotics by Mn oxides and oxyhydroxides in soils and related environments warrant investigation. 

A seven year smdy on the groundwater in the Paris region of France, revealed DEA was present at a concentration above that of its parent compound. The atrazine degradation pathway and the higher solubility of DEA in water may explain this finding. Recent work showed that photolysis of triazines and acetanilides followed pseudo first order kinetics, and the photodegradation in soils was accelerated as the content of organic matter increased. Another study showed that humic substances enhanced terbutylazine photolysis. ... 

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