Petrochemistry and Chemical Engineering

The greenhouse gases which are majorly CH₄ and CO₂ have raised concerns throughout the world due to their link to global warming and climate change. Research is ongoing to develop methods that can be applied commercially for the utilization of flue gases into useful products such as syngas. There are methods currently in use commercially such as the steam reforming and partial oxidation reforming for syngas production, but due to the requirement of very high operating temperatures, these methods are not usually economical for commercial syngas production. Recently, the use of membrane technology has drawn so much interest. In this study, a CO₂ reforming method employing a catalytic membrane reactor process was built to study the CO₂ reforming of methane. The membrane used was a tubular mesoporous tube consisting of Al₂O₃, with the rhodium catalyst impregnated into its pores by the wet impregnation method. The impregnation method allows for the catalyst to be deposited into the pores on the outer surface of the membrane. A flue gas stream comprising of CO₂-12.5%, CH₄-2.5%, CO-50ppm, N₂-80.595%, O₂-4.4% was feed into the reactor system as soon in figure 1 under various operating conditions: temperature range 700^oC-900^oC and flowrates of 0.45 and 1.50 Lmin-1. The exit stream was connected to a GCMS which was used to interpret the results. At 700^oC, no conversions were realized but at 900^oC, CO₂ and CH₄ conversions reached above 94%. Our catalytic membrane process is therefore a viable and effective technological breakthrough which converts the two most important greenhouse gases CH₄ and CO₂ into valuable syngas without the need for CO₂ pre-separation from flue gas.