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The reaction of CCl 3 F (CFC-11) with CH 4 in a non-equilibrium plasma has been examined. CFC-11 has the highest ozone depleting potential (ODP) among all refrigerants used commercially (ODP value of 1) and also has very high global warming potential (GWP) of 4680 and an atmospheric lifetime of 45 years.1 The manufacture of CFC-11 was banned by the Montreal Protocol in 1996 due to its deleterious effects on Earth's ozone layer. It is widely recognized that significant quantities of CFC-11 remain in polyurethane foams in discarded refrigerators or refrigerators awaiting disposal. While there are several methods developed to recover CFC-11 from polyurethane foams, a suitable process is required for its disposal. In this study, a dielectric barrier discharge reactor, employing alumina dielectrics (the detail description can be founds in2, 3), has been applied for the conversion of CFC-11 with the aim of synthesizing value-added materials. It has been found that polymers of non-crosslinked architecture can be synthesized from the reaction of CFC-11 and CH 4 . This work is focused on structural analyses of the polymers as well as discussions on conversion of CFC-11 under various conditions and characterization of the electrical discharge.

Non-thermal plasma polymerization of HFC-134a in argon bath gas has been studied in a dielectric barrier discharge reactor at atmospheric pressure and in the absence of oxygen and nitrogen. The reaction resulted in the formation of a polymeric solid fraction and the non-crosslinked properties of this material assisted in its characterization by solution state 13C and 19F NMR spectroscopy. Gel permeation chromatography (GPC) revealed that the polymers include low (number average molecular weight, Mn values between 900 g mol-1 and 3000 g mol-1) and high (Mn approximately 60 000 g mol-1) molecular weight fractions. A detailed polymerization mechanism is proposed, based on published literature and the findings of the current investigation.

Summary form only given. In this paper we present the results of a study of the reaction of chloroform under non-oxidative conditions, in a non thermal plasma. Reactions were at atmospheric pressure, in a double dielectric barrier discharge reactor. The non-oxidative atmosphere provides a distinct advantage as it precludes the formation of hazardous and undesired products such as COCl2, compounds which have been observed during reaction under oxidative conditions1. We postulate a mechanism for formation of major gas phase product species in the reaction, along with the characterization of the polymer formed during the reaction. A detailed description of the reactor and power supply are provided in our prior publication2. The concentration of chloroform in the feed was maintained at a constant level of 1 %, the remainder being argon. Applied voltage for the experiments was varied over the range 12-16 kV (peak to peak). The conversion of chloroform was found to increase with an increase in the applied voltage, the highest being 66.7% at 16 kV. Micro-GC and GC were used to analyze the gas phase products except the acid gases, for which an FTIR was used. The major gas phase product species observed were CH2Cl2, C2HCl3, C2Cl4, CCl4 and HCl. A mass balance of 97% was obtained for reaction at 16 kV. GPC and NMR (1-D and 2-D) techniques were employed to characterize the polymer obtained. The polymer is non-cross linked and dissolves readily in THF. This is a very important characteristic from a practical point of view. Molecular weight of the polymer obtained were characterized as follows: Mn 47400 g mol-1, Mw 80100 g mol-1. The polydispersity was estimated to be 1.69. Evidence of CH2 groups adjoining CHCl groups in the polymer backbone chain, CHCl2 groups and double bonds is seen in the NMR spectra.