The aluminium industry is the major source of perflurocarbon (PFC) emissions to the atmosphere, which are a major contributor to global warming. PFCs have greenhouse gas effects up to 10000 times that of CO2. Emissions have been reduced over the last 20 years, but further reductions are harder to achieve as all the mechanisms for PFC production are not known. In order to better understand the production of PFC on an industrial level, laboratory studies have been carried out using a small scale cell.
A controlled potential electrolysis was combined with gas analysis using Protea gas analysers to study the PFC production. By studying the behaviour of cells before and during the anode effect time and measuring the composition of the off-gases, further knowledge of the PFC production process was gained. This can be used to identify signs that can be used as early warnings for anode effect.
The combination of Quadrupole Mass Spectrometry (QMS) and Fourier Transform Infra-Red (FTIR) spectroscopy was used to provide full-species measurement of the process. The fast response of the MS and the high resolution of the FTIR is a powerful tool to determine the gas composition.