Process Control and Investigation of Oxidation Kinetics of Postoxidative Effluents Using Gas Chromatography with Pulsed Flame Photometric Detection (GC-PFPD)

Abstract

This article presents the results of investigations on the use of headspace analysis and gas chromatography with pulsed flame photometric detection (HSA-GC-PFPD) to evaluate the effectiveness of oxidation of postoxidative effluents from the production of bitumens. Samples of effluents from the bitumen oxidation unit were used in the experiments. In addition, the kinetics of effluent oxidation was also investigated. The content of volatile sulfur compounds (VSCs) was determined using HSA-GC-PFPD. The results were correlated with chemical oxygen demand (COD). The changes in concentration of individual volatile sulfur compounds in the course of effluent oxidation were measured, which enabled the determination of the order of the oxidation reactions. The usefulness of the determination of VSCs in the headspace as a reliable technique for evaluating the reduction in emissions of volatile malodorous compounds was demonstrated. The developed method is also useful for process control of the oxidation of postoxidative effluents. The procedure ensures an objective evaluation of the effectiveness of the removal of volatile sulfur compounds from postoxidative effluents. The experimental results revealed that the effectiveness of the oxidation of organosulfur compounds was much higher than that of other classes of organic compounds. Furthermore, the order of oxidation reactions along with the rate constants of thiophenol, p-thiocresol, and hydrogen sulfide were determined. An advantage of the developed procedure is that it can be automated.