Sie befinden Sich nicht im Netzwerk der Universität Paderborn. Der Zugriff auf elektronische Ressourcen ist gegebenenfalls nur via VPN oder Shibboleth (DFN-AAI) möglich. mehr Informationen...
Oxidation of benzoic acid by heat-activated persulfate: Effect of temperature on transformation pathway and product distribution
Ist Teil von
Water research (Oxford), 2017-09, Vol.120, p.43-51
Ort / Verlag
England: Elsevier Ltd
Erscheinungsjahr
2017
Link zum Volltext
Quelle
MEDLINE
Beschreibungen/Notizen
Heat activates persulfate (S2O82−) into sulfate radical (SO4−), a powerful oxidant capable of transforming a wide variety of contaminants. Previous studies have shown that an increase in temperature accelerates the rates of persulfate activation and contaminant transformation. However, few studies have considered the effect of temperature on contaminant transformation pathway. The objective of this study was to determine how temperature (T = 22–70 °C) influences the activation of persulfate, the transformation of benzoic acid (i.e., a model compound), and the distribution of benzoic acid oxidation products. The time-concentration profiles of the products suggest that benzoic acid was transformed via decarboxylation and hydroxylation mechanisms, with the former becoming increasingly important at elevated temperatures. The pathway through which the products were further oxidized was also influenced by the temperature of persulfate activation. Our findings suggest that the role of temperature in the persulfate-based treatment systems is not limited only to controlling the rates of sulfate and hydroxyl radical generation. The ability of sulfate radical to initiate decarboxylation reactions and, more broadly, fragmentation reactions, as well as the effect of temperature on these transformation pathways could be important to the transformation of a number of organic contaminants.
[Display omitted]
•The degradation of benzoic acid by heat-activated persulfate was studied.•Temperature affects the distribution of benzoic acid transformation products.•The mechanism through which benzoic acid is transformed was established.•The roles of temperature in heat-activated persulfate systems are discussed.