Treatment of Methyl tert-Butyl Ether Contaminated Water Using a Dense Medium Plasma Reactor:  A Mechanistic and Kinetic Investigation

Abstract

Plasma treatment of contaminated water appears to be a promising alternative for the oxidation of aqueous organic pollutants. This study examines the kinetic and oxidation mechanisms of methyl tert-butyl ether (MTBE) in a dense medium plasma (DMP) reactor utilizing gas chromatography-mass spectrometry and gas chromatography-thermal conductivity techniques. A rate law is developed for the removal of MTBE from an aqueous solution in the DMP reactor. Rate constants are also derived for three reactor configurations and two pin array spin rates. The oxidation products from the treatment of MTBE-contaminated water in the DMP reactor were found to be predominately carbon dioxide, with smaller amounts of acetone, tert-butyl formate, and formaldehyde. The lack of stable intermediate products suggests that the MTBE is, to some extent, oxidized directly to carbon dioxide, making the DMP reactor a promising tool in the future remediation of water. Chemical and physical mechanisms together with carbon balances are used to describe the formation of the oxidation products and the important aspects of the plasma discharge.

Degradation of Azo Dye Acid Red 88 by Gas Phase Dielectric Barrier Discharges

“…Its attractive feature lies in the ability to generate highly reactive species such as OH • radicals. Most advanced oxidation technologies developed such as photocatalytic oxidation and pulsed electrical discharges focus on OH • radical production directly in the aqueous phase [9][10][11][12][13][14][15][16]. Gas-phase electrical discharge reactors such as dielectric barrier discharge (DBD) and pulsed corona discharge, on the other hand, have long been used to generate ozone (O 3 ), a relatively selective oxidant, with clean dry air or pure oxygen [17,18].…”

“…The change of pH of the solution with treatment time at gas flow rate of 7 L min -nitrite ions, probably through reactions (13)-(15) …”

A Review of Combined Advanced Oxidation Technologies for the Removal of Organic Pollutants from Water

“…2, otherwise called electrohydraulic discharge (HER). This technology is widely considered due to non-addition of external chemicals, environmentally compatibility, effectiveness, simplicity of operation at ambient temperature and pressure (Johnson et al 2003;Sun et al 2000;Locke et al 2006;Sato et al 2008;Even-Ezra et al 2009;Krause et al 2009;Zhang et al 2013;Jiang et al http://repository.uwc.ac.za 6 2014). Other advantages of corona discharge system include greater efficiency, nongeneration of secondary pollution, ability to kill microbes, and high efficiency ).…”

Detection Limits and Decomposition Mechanisms for Organic Contaminants in Water Using Optical Emission Spectroscopy

“…Ultimately, this situation led to a 2003 ban on the use of MTBE as a gasoline additive in California 2, 6, 7. Because MTBE is now ubiquitous in water sources worldwide, development of methods for both detection and decontamination have been the objective of many scientific studies in the past decade 1–5, 8, 9. Another example where ultrapure water is critical is in the microelectronics industry 10, 11.…”